1. family and parenting
2. motherhood
3. pregnancy

Friday,
0815
May 10
Title:
NONINVASIVEDETERMINATIONOF CARDIAC OUTPUT
THROUGHOUT
PREGNANCY
Authors :
James CF”,
Affiliation:
Departments
Gynecology,
Gainesville,
Banner T, Levelle
JP,
and Cato”
8501
D
of Anesthesiology
and Obstetrics
and
University
of Florida
College
of Medicine,
Florida
32610-0254
Introduction.
Longitudinal
studies
of cardiac
output (CO) during
pregnancy are scant and the time until
CO peaks is ill defined.
Doppler
determination
of CO correlates
strongly
with the thermodilution
method
(1) and has been applied
to term pregnant patients
(2).
This study
focuses
on CO trends between early and term gestation
to further
define
CO changes during normal pregnancy.
Methods.
Seven pregnant patients,
who gave informed consent as
required
by the Institutional
Review Board, were studied
from less than
12 weeks of pregnancy until
term.
Measurements taken more than 4 weeks
after
delivery
served as baseline
values.
Another 10 women, matched for
served
as
controls.
CO
was
measured
by
a Doppler computer
age>
(Ultracorn,
Lawrence Medical Systems, Inc.)
every 2 to 4 weeks in the
supine (throughout
gestation)
and left
tilt
(> 29 weeks) positions.
Multiple
determinations
of CO were made at each interval
by a tw” phase
method, which included
measuring ascending
root diameter by A-mode
echocardiography
and aortic
blood velocity
with a continuous
wave
transducer.
CO was then calculated
by taking the product of systolic
velocity
integral,
cross-sectional
area of the aorta (computed from
aortic
diameter),
and heart rate (HR).
Measurements during gestation
were divided
into 2 to 4 week groups (except
1st group: _< 12 weeks) for
statistical
analysis,
which included
ANOVA.
Results.
Mean CO among pregnant patients
was unchanged from baseline
values by 16 weeks of gestation,
reached a 36% peak increase
wer
baseline
levels
by 25 to 28 weeks of gestation,
and declined
towards
baseline
levels
between 35 and 40 weeks.
The % change in CO among
pregnant patients
was statistically
significant
“ver time, despite
substantial
individual
variation
of CO. There was no statistical
significance
in HR or stroke volume “ver time.
CO among individual
control
patients
varied by a mean of 26% (range:
10% to 44%) (not
statistically
significant
“ver time).
CO did not differ
statistically
between supine and left
tilt
positions
from 29 to 40 weeks gestation.
Discussion.
This study showed that, despite
marked individual
variability
in CO among nonpregnant
patients,
CO increased
significantly
among all pregnant patients
during mid trimester.
Unlike previous
reports,
CO during late gestation
(35-40 weeks) did not differ
from that
during early gestation
(< 16 weeks) or from baseline
CO. MOreOVer,
there was no difference
7” CO during the last 12 weeks of gestation
when
supine and left
tilt
positions
were compared.
References
1. Chandraratna PA, Nanna M, McKay C, et al:
Determination
of cardiac
output by transcutaneous
continuous-wave
ultrasonic
Doppler computer.
Am J Cardiol
53:234-237,
1984.
2. James CF, Caton D, Banner T:
Noninvasive
determination
of cardiac
nutput during cesarean
section.
(Abstract)
Anesthesiology
61:A411,
1984.
,12
Friday, May 10
0825
Title:
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NONINVASIVE DETERMINATION OF CARDIAC OUTPUT DURING
VAGINAL DELIVERY
Authors:
Levelle JP", James CF, Banner T, and Cato" D
Affiliation:
Departments of Anesthesiology and obstetrics and
Gynecology, University of Florida College of Medicine,
Gainesville, Florida
32610-0254
8502
Doppler determinations of cardiac output (CO) have
Introduction.
been correlated with thermodilution measurements (1). Recently, CO
determinations were made during cesarea" section with general and
epidural anesthesia (2). The present study, an extension of that work,
compares CO changes during vaginal delivery with those during cesarea"
section with epidural anesthesia.
Methods.
Seven term pregnant patients, who gave informed consent as
required by the Institutional Review Board, were studied during labor
and vaginal delivery with epidural anesthesia.
CO was measured by a
Doppler computer (Ultracorn, Lawrence Medical Systems, Inc.) before
delivery (first stage of labor without contractions) and 15, 30, 60, and
90 min and 24 h after delivery. Multiple determinations of CO were made
at each interval by a tw" phase method, which included measuring the
ascending root diameter by A-mode echocardiography and the ascending
aortic blood velocity with a continuous wave transducer.
CO was then
calculated by taking the product of systolic velocity integral,
cross-sectional area of the aorta (computed from aortic diameter), and
heart rate (HR). Statistical analysis consisted of analysis of variance
with subsequent Duncan multiple range tests.
Results. CO increased early after delivery in 6 of 7 patients.
Compared with predelivery measurements, mean CO increased 37%
(range: -5% t" +80%) by 15 min after delivery. Mean CO at 15 min
differed significantly from values at all other intervals. Smaller
peaks in mea" stroke volume and HR occurred by 15 min after delivery and
were not statistically significant.
Similarly, in the previous study of
cesarea" section patients under epidural anesthesia, mea" CO increased
32% by 15 to 30 min after delivery (2). CO during vaginal delivery did
not differ statistically from that during cesarea" section with epidural
anesthesia.
Discussion.
CO increases consistently within 15 min of either
vaginal delivery with epidural anesthesia or cesarean section with
epidural anesthesia.
With this method of measuring CO, CO of high-risk
obstetric patients may be subsequently compared with that of normal
patients.
References
1. Chandraratna PA, Nanna M, McKay C, et al: Determination of cardiac
output by ttanscutaneous continuous-wave ultrasonic Doppler computer.
Am J Cardiol 53:234-237, 1984.
2. James CF, Caton D, Banner T: Noninvasive determination of cardiac
output during cesarean section. (Abstract) Anesthesiology 61:A411,
1984.
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13
Friday. Mav 10
0825 ” ’
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Title:
CARDIAC OUTPUT CHANGES DURING PROSTAGLANDIN-INDUCED
SECOND TRIMESTER TERMINATION OF PREGNANCY
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Authors:
Levelle JP*, Willis DC, Banner T, Cato" D, and Cruz A
Affiliation:
Departments of Anesthesiology and Obstetrics and
Gynecology, University of Florida College of Medicine,
Gainesville, Florida
32610-0254
Introduction.
Prostaglandi" E2 (PGE~), a drug with cardiovascular
effects (l), is often used for termination of pregnancy (TOP) during the
second trimester in women with heart disease. The hemodynamic effects of
inducing second trimester TOP with this drug have not been documented.
This study describes the changes in cardiac output (CO), stroke volume
(SV), and heart rate (HR) as determined by a noninvasive Doppler method of
CO determination (2) during PGEZ-induced second trimester TOP.
Methods.
Informed consent was obtained from 12 women with no known
cardiovascular disease who were scheduled for PGEP-induced second
trimester TOP for medically indicated reasons. Duration of pregnancy
ranged from 15-23 weeks. Before the placement of a 20-mg PGEZ vaginal
suppository (Prostin E2, Upjohn), CO, SV, and HR were measured by a
noninvasive Doppler CO computer (Ultracorn, Lawrence Medical Systems,
1°C.).
The measurements were repeated approximately every 90 minutes
after labor was induced and 1 hour and 24 hours after TOP.
Results.
The CO increased shortly after induction and reached a
maximal value just before TOP. By 1 hour after TOP, CO "early returned to
preinduction levels. The mea" increase in CO was 64%; however, there was
much individual variation (range 20-116%). The magnitude of increase in
CO was related only to baseline CO (r = 0.684, p < 0.05) by regression
analysis. The increase was not related to duration of pregnancy, parity,
duration of induction, body temperature, number of doses of PGEZ, or
whether the fetus had been viable (n = 7) or had died in utero (n = 5).
Discussion.
Prostaglandin Es are know" to increase CO. This study
demonstrates that CO substantially increases during TOP induced by PGE2
whether the fetus is viable or not. The mean increase in CO (64%) is
similar to that reported for term patients in spontaneous labor (3). This
finding may be significant to the use of TOP for patients with limited
cardiac reserve.
References
1. Nowak J, Weenmalm A: Influence of indomethacin and of prostaglandin
El on total and regional blood flow in ma". Acta Physiol Stand
102:484-491, 1978.
2. Huntsman LL, Stewart DK, Barnes SR, Franklin SB, Colocousis JS,
Hessel EA: Noninvasive Doppler determination of cardiac output in
man. Clinical validation.
Circulation 67:593-602, 1983.
3. Ueland K, Hansen JM: Maternal cardiovascular dynamics.
III. Labor
and delivery under local and caudal analgesia uterine contractions.
Am
J Obstet Gynecol 103:8-18, 1969.
13A
8503
Friday, May 10
0845
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Title:
PRECORDIAL ULTRASONIC DOPPLER MONITORING DURING
CESAREAN DELIVERY
Authors:
Malinow AM*, Naulty JS, Helton BA, Hunt CO, Langston GM,
Datta S, Stone JJ, Weiss JB, Ostheimer GW.
Affiliation:
Department of Anesthesia, Brigham and Women's Hospital,
Harvard Medical School, Boston, Massachusetts
02115.
8504
Air embolization has been reported to occur during a wide
Introduction.
A precordial doppler is capable of detecting
variety of surgical procedures.
as little as O.lml of intra-cardiac air and may alert the surgical team to
the presence of air emboli before significant cardiopulmonary sequelae occurs.'
In this study, we randomly selected 47 parturients who were to
Methods.
undmctive
cesarean delivery.
Precordial ultrasonic doppler monitoring
is considered a routine form of monitoring in our institution; therefore,
patient consent was adjudged unnecessary.
None of the women were in labor
and all were acutely hydrated according to our standard protocol. A Parks
Medical Electronics Model 915L Dual Frequency Ultrasonic Doppler (2MHz)
transducer was placed parasternally in the 4th right intercostal space.
Position of the transducer was confirmed with the detection of Doppler sound
changes seconds after the bo us infusion of intravenous fluid through the
peripheral intravenous line.;1
Results. Nineteen of the women demonstrated Doppler sound changes (Doppler
posiiuring
the procedure: 10 at the time of hysterotomy, 1 with delivery
of the baby, 5 with delivery of the placenta, and 3 with repair of the uterus.
Nine of the Doppler positive women complained of chest discomfort within 1-6
minutes of Doppler sound change detection; only 1 of the 28 women without
Doppler sound changes (Doppler negative) complained of chest discomfort.
Additionally, three of the Doppler positive women complained of dyspnea.
Changes in blood pressure and pulse occurred in Doppler positive and Doppler
negative women. The uterus was delivered abdominally for repair in 12 of the
Doppler positive women.
Discussion.
We have observed precordial ultrasonic Doppler changes in 40%
of women at cesarean delivery.
47% of these women complained of chest pain
thereafter while only 3.5% of women without precordial ultrasonic Doppler
changes complained of chest pain. Precordial ultrasonic Doppler monitoring is
a sensitive but not very specific method of air embolus detection.
Further
attempts at delineating these Doppler changes as being air emboli employing
capnography and mass spectrometry of end tidal gases are planned. The presence
of chest discomfort during cesarean delivery should alert the anesthesiologist
to the possibility of air emboli. Continuation of this pain with dyspnea and/or
hemodynamic changes should raise the specter of clinically significant air emboli
which may require therapy to prevent the continued venous entrainment of air.
References.
1. Michenfelder JD, Miller RH, Gronert GA.: Evaluation of an ultrasonic
device (Doppler) for diagnosis of venous air embolism. Anesthesiology
36:164-167, 1972.
2. Naulty JS,.Ostheimer GW, Datta S, Knapp R, Weiss JB.: Incidence of
venous air embolism during epidural catheter insertion. Anesthesiology
57:410-412, 1982.
14
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Friday, May 10
0900
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Title:
A COMPARISON
Authors:
Hubbard L,* Lang C, Greenhouse BB, and Sheikh F
Affiliation:
Department of Anesthesiology,
Albany, New York
OF CVF vs SWAN-GANZ CATHETER IN THE MANAGEMENT OF THE MODERATE TO SEVERE PPE-ECLAMPTIC--A PRACTICAL
APPROAM
Albany Medical College,
Introduction.
To prevent pulmonary edema in the pre-eclamptic p tient
in labor, hemodynamic monitoring at this time is not conclusive. 1,g
Extensive monitoring such as a pulmonary artery catheter is demonstrated to show the earliest signs Of cardiac failure, however, it is
not always readily available at a large proportion of delivery suites.
Methods. TO assess pulmonary artery catheters in the management of
these patients, we looked at the relationship of pulmonary capillary
wedge pressure (PCWP) to central venous pressure (CVP) in 10 consecutive
patients.
Retrospectively, 15 patients had CVP's only.
Results. Arterial lines were placed in all patients and a Swan-Ganz
catheter or a CVP line was placed and the patient was hemodynamically
stabilized to CVP 4-5 prior to epidural placement.
All patients had a
mean arterial pressure of 110 or greater, proteinuria, increased
reflexes and edema.
This was exhibited and augmented if necessary with
albumin or fluid administration and maintained to the post-partum period.
At the time of line placement, pre-parturn CVP and PCWP showed correlative rises and falls +3 tar+.
Urine output was maintained or increased
to greater than 30ccfiour with the CVP at this level. Post-partum the
Swan-Ganz catheters were converted to a CVP which was measured serially.
Two patients exhibited pulmonary edema when the CVP was allowed to rise
greater than 10. In all other 18 patients CVP's were maintained at
4-6 to0 by careful fluid titration.
No pulmonary edema was exhibited.
Discussion.
In conclusion, although Swan-Ganz catheter monitoring is
ideal, it is not always practical OI feasible in every institution ox
situation. We have tried to demonstrate that if the change in CVP is
carefully monitored with fluids titrated to maintain a CVP of 4-G. with
adequate urine output, that the moderate to severe pre-eclamptic can be
adequately and safely managed.
References.
l.Cotton DB, Benedetti TJ: Use of the Swan-Ganz catheter in obstetrics
and gynecology.
Obstet Gynecol 56(5):641-645, Nov. 1979.
2.Benedetti TJ, Cotton DB, Read JA, et al: Hemodynamic observations
in severe preeclsmpsia with a flow directed pulmonary artery catheter.
Am J Obstet Gynecol 136:465, 1980.
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8505
Friday, May 10
0915
Title:
THE ROLE OF INTRAVENOUS NITKOGLYCERIN
IN THE TREATMENT OF SEVERE PREGNANCY-INDUCED
HYPERTENSION COMPLICATED BY PULMONARY EDEMA
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Authors:
Cotton DE*, Jones MM, Longmire S, Dorman
K, Joyce TH
Affiliation:
Departments of Obstetrics and Gynecology
and Anesthesiology, Baylor College of
Medicine, Houston, Texas
The management
of pulmonary
edema
in severe
Introduction.
pregnancy-induced
hypertension
(PIH) has traditionally relied upon
While both
oxygenation, diuresis and occasionally
digitalization.
cardiogenic and non-cardiogenic mechanisms have been implicated in PIH
We recently
pulmonary
edema the treatment has remained uniform.
investigated the use of intravenous nitroglycerin (IVNTG) in patients
with severe PIH complicated by pulmonary edema.
patients with severe PIH
Methods.
To date, three antepartum
complicated
by pulmonary
edema have been identified.
The mean
arterial pressure in all patients was > 126mmHg. A pulmonary arterial
and a radial arterial catheter were izserted prior to institution of
IVNTG. A baseline set of hemodynamic measurements including arterial
and mixed venous blood gases was obtained and IVNTG instituted.
Hemodynamic
measurements
were repeated after observing the expected
decline in pulmonary capillary wedge pressure.
Results. Hemodynamic and oxygenation parameters obtained prior to
and after institution of IVNTG are as follows (mean -+ SD):
HR
PreNTG
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8506
Post-NTG
1057 11
107 -+12
NAP
--148 + 19
125 T 10
CVP
9 + 3
77- 4
PCUP
27 t 4
14-t
- 6
COP
17.3 t 1.5
16.17- 1.5
COP-PCUP
gradient*
Pre-NTG
Post-NTG
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* ~(0.05;
Discussion.-
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-10 t 2
2+5
_
pao,
69 + 6
72 +
_ 8
=
145 + 30
223 7
_ 50
o$xt*
0.25
0.37
Shunt
28% t 7%
21% +
- 4%
V021 = Oxygen Consumption
Index
O2 Ext = O2 Extraction
COP = Colloid Osmotic Pressure
1) The mechanism
of pulmonary
edema in these three
antepartum patients appeared to be primarily hydrostatic.
2) IVNTG
rapidly improved
the primary derangement
in the colloid
osmotic
pressure-pulmonary capillary wedge pressure gradient in these three
patients with PIH complicated
by pulmonary
edema.
3) Although a
modest improvement in pulmonary shunt fraction was seen with IVNTG, a
rapid improvement
in Pa02 did not occur.
4) IVNTG appears to be
beneficial
in pulmonary
edema
by rapidly
correcting
altered
hydrostatic
forces however the lack of immediate
improvement
in
oxygenation
suggests
that diuresis
will remain the mainstay
of
therapy.
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Friday,
May 10
0930
TITLE:
AUTHORS:
HEMODYNAMIC
EFFECTS
OF NITKOGLYCEKIN
IN PIH
S. Longmire,
M.D.*, M. Jones, M.D., J. Tessem,
M.D.,
D. Cotton, M.D., K. Dorman, R.N., B.S., T. Joyce, III, M.D.
Departments
of Anesthesiology
and Obstetrics
and
AFFILIATION:
Baylor College of Medicine, Houston, Texas 77030
Gynecology,
We investigated
nitroglycerin
(NTG) as an agent for
Introduction:
controlling blood pressure in severe pre-eclamptics undergoing caesarean
section.
The study was approved by the IRB. Six primigravidas, with a
Methods:
age of 18.3 years and mean gestational
age of 37.9 weeks were
mean
consent.
Inclusion criteria were: age >
studied with written informed
18 yrs., gest. age > 26 wks., blood pressure (BP) > 160/100, and/or
pressure,
eclampsia.
Monitoring
consisted of ECG, radial arterial
thermodilution PA catheter, uterine contractions, and fetal heart rate.
Measurements
were first recorded 15 minutes after all monitoring was
connected. Measurements were made before and after volume-expansion, both
with and without NTGinfusion,
as well as before leaving the ICU, preduring intubation,
and after delivery
of the placenta.
induction,
100 mg were used for rapid
Thiopental
3 mg kg-' and succinylcholine
sequence IV induction.
Laryngoscopy
and intubtiion did~not exceled 33
sec. Anesthesia was maintained with 02 4 1 min
,
N2014 1 min
, and
halothane 0.5% until delivery,
when mar hine 200 ug kg
IV was given,
the flow of 02 was changed to 2 1 min -P , and the halothane gradually
discontinued.
Muscle
relaxation
was provided
using an infusion of
succinylcholine
(0.2%).
Results:
No significant change in heart rate (HR) occurred durin
the
initial infusion of NTG, but a gradual increase (88 - 98 beats min -', NS)
occurred during stabilization
in the ICU prior to transport to the OR,
and
up"" arrival
in OR (101 - 112, p < 0.05). Prompt reductions
of
Systolic (187 - 163 mmHg, NS), Diastolic (104 - 88 mmHg, p < 0.05), and
Mean (132 - 113 mmHg, p < 0.05) Arterial Pressures, and PA Pressures
(20/12 - 15/9_nmHg,
NS; PCWP 10 - 6 mmHg, p < 0.05) were achieved wir:
mine1 III non-expanded
patients; m"re than 12 ug kg
on1~11.2
kg
min
was"grequired
in volume-expanded
patients for similar reductions.
Cardiac Index decreased only slightly (3.7 - 3.1 1 min-' mm2, NS), and
SVRI and PVRI did not change at all during NTG infusion in non-expanded
but significant decreases in SVRI and PVRI (2858 - 2133 dyne
:,":'::?ll2, p < 0.01; 127 - 73 dyne set cmm5 m2, p < 0.05)were seen in
NTG-infused/volume-expanded
patients,
and Cardiac
Index increased
significantly
(3.1 - 4.3 1 mine1
m-2,
The only
p < 0.01).
statistically
significant
difference
found in comparing
the postexpansion NTG group with the ICU baseline was tht: a large reduction in
the dose of NTG occurred (12 - 2.5 ug kg-' min
p < 0.01) while BP
remained unchanged, and Cardiac Index and SVRI b";h improved slightly.
Diastolic BP (92 - 102 mmHg, p < O.Ol), and SVRI (2021 - 2625 dyne set
cmm5 m2, NS) increased, and Cardiac Index (4.7 3.9 1 min-l
m-2,
NS) decreased on arrival in OR. No statistically significant changes in
hemodynamics occurred during the Pre-induction period, although the mean
NTG rate was doubled.
Large increases in Maternal
HR (113 - 133, p <
O-05), and BP (190/103 - 224,'123 mmHg, NS), occurred
at intubation,
in one patient, a
despite a mean NTG infusion rate of 29 ug kg-' mine';
dose as high as 135 ug kg-' min-' failed to control the rise in BP (which
peaked at 320/158).
Conclusions:
1. NTG does not blunt increases in HR during intubation.
2. NTG does not blunt increases in Maternal
BP during intubation.
3. Infusion of NTG in volume-expanded severe pre-eclamptics is associated
with significant increases in Cardiac Index, and significant decreases in
SVRI and PVRI.
8507
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Friday, May 10
0945
Title: Use of Nifedipine and Verapamil to Counteract Hypertension in
Gravid Ewes.
8508
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Authors: Norris MC*, Rose JC, Dewan DM
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Affiliation: Wake Forest University, Winston-Salem, North Carolina
Introduction: Endotracheal intubation in the patient with severe preeclampsia may result in pulmonary edema or subarachnoid hemorrhage(l).
The calcium entry blocking drugs nifedipine (N) and verapamil (V) are
effective antihypertensives in the non-pregnant patient. We have used
these drugs in chronically instrumented gravid ewes made hypertensive
with an infusion of norepinephrine (NE).
Methods: We studied 8 gravid ewes 110-130 days gestation (term 145
days). At least 3 days following surgical preparation, we continuously
monitored maternal mean arterial pressure (MAP), maternal heart rate
(MHR), uterine blood flow (UBF), fetal mean arterial pressure (FAP) and
fetal heart rate (FHR). Following a control period, during which all
measurements stabilized, we infused NE at 77.3 + 10.0 ug.min-1 to increase
MAP to 20% above control. We then gave 2mg N or 10 mg V by slow IV injection and monitored all parameters for 20 min. We used a multiple analysis of variance for repeated measures to analyze the data, pCO.05 was
considered significant.
Results: MAP returned promptly (within 2 min) to control values following either drug. MHR decreased significantly during NE hypertension.
N caused a significant maternal tachycardia which persisted throughout
the study. In contrast, MHR returned only to control level following
V. FHR and FAP were unchanged throughout the study. UBF decreased
5O-60% during NE hypertension, there were no further changes followi,,g
either N or V.
Discussion: Preinduction control of maternal BP may prevent that significant morbidity that can occur following laryngoscopy and intubation
in the severely pre-eclamptic patient. An agent which rapidly decreases
maternal BP without adverse effects on an already compromised fetus may
be useful in this circumstance. Calcium entry blocking drugs are effective in the management of acute and chronic hypertension(2). In this
study, both N and V rapidly and effectively returned MAP to control
levels. While N caused a significant reflex tachycardia, V, with its
greater negative inotropic properties, resulted only in a return of MHR
to control values. In normotensive ewes, V has been shown to decrease
UBF lo-25%(3) while N has no effect(4). In this study of hypertensive
ewes, neither drug was associated with any further decrease in UBF.
References:
1. Hodgkinson R, Husain FJ, Hayashi RH: Systemic rindpulmonary blood
pressure during caesarean section in parturients with gestational
hypertension. Canad Anaesth Sot J 27:389-393, 1980.
2. Singh BN, Hecht HS, Nademanee K, Chew CYC: Electrophysiologic and
hemodynamic effects of slow channel blocking drugs. Prog Cardiovasc
Dis 25:103-132, 1982.
3. Murad SHN, Tabsh KMA, Shilyanski G, Kapur PA, Mn C, Lee C, Conklin KA:
Effects of verapamil on uterine blood flow and maternal cardiovascular
function in the awake pregnant ewe. Anesth Analg 64:7-10, 1985.
4. Norris MC, Rose JC, Dewan DM: Maternal and fetal effects of nifedipine in the gravid ewe. Unpublished.
18
Friday, May 10
1.000
Title:
Maternal and Fetal Effects of Nifedipine in the Gravid Ewe
8509
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Authors:
Norris MC*, Rose JC, Dewan DM
Affiliation:
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Wake Forest University, Winston-Salem, North Carolina
Introduction:
Nifedipine (N), a potent calcium entry blocking
drug, has been show" to be effective in the treatment of premature
labor(l) and may also be useful in the management of pre-eclampsia(2).
We have studied the maternal and fetal effects of N in the chronically
instrumented ewe.
Methods. We studied 8 chronically instrumented gravid ewes, 115-136
days gestation (term 145 days). All were rested at least 3 days following surgery. We continuously monitored maternal heart rate (MHR),
maternal mea" arterial pressure (MAP), uterine blood flow (UBF) and
fetal mean arterial pressure (FAP). Following a control period,
during which all measurements stabilized, we injected vehicle (propylene glycol, ethyl alcohol, and water) as a control or 1,2, or 4 mg N
IV over 15 s. The hemodynamic response was monitored for 60 min. Maternal and fetal arterial blood was sampled before and 10 min after
injection. We compared the data using a multivariate analysis of
variance for repeated measures, pcO.05 was considered significant.
Injection of vehicle caused no change in MHR of MAP. lmg
Results:
N caused a 19% increase in MHR which persisted for 8 min. There was
no change in MAP. MHR increased 24% following 2mg N and returned to
control by 11 min. There was no significant change in MAP. Injection
of 4mg N resulted in a 26% increase in MHR. By 40 mi", MHR was not
significantly different from control. MAP initially decreased 15%
and remained significantly below control for 5 min. UBF did not change
with any dose of N. FAP as well as maternal and fetal ABG's were unchanged throughout the study.
The hemodynamic effects of N reported here, a transient
Discussion:
or absent decrease in MAP and significant reflex tachycardia, are
similar to those reported elsewhere in normotensive animals(3) and
The lack of any significant effect on UBF, FAP and fetal
huma"s(4).
acid-base status is reassuring in light of the possible use of N in
parturients with potentially compromised fetuses.
References:
1. Ulmste" U, Andersson K-E, Winegerup L: Treatment of premature
labor with the calcium antagonist nifedipine.
Arch Gynecol
229:1-5, 1980.
2. Zaret GM: Possible treatment of pre-eclampsia with calcium
channel blocking agents. Med Hypoth 12:303-319, 1983.
3. Hintze TH, Vatner SF: Comparison of effects of nifedipine and
nitroglycerin on large and small coronary arteries and cardiac
function in conscious dogs. Circ Res (Suppl 1) 139-146, 1983.
4. Kleinbloesem CH, van Brummelen P, van de Linde JA, Voogd PJ,
Breimer PD: Nifedipine kinetics and dynamics in healthy subjects.
Clin Pharm Ther 35:742-749, 1984.
-
19
-~~
Friday, May 10
1015
CONTROL OF NOREPINEPHRINE INDUCED HYPERTENSION
EWES WITH PROPRANOLOL AND SODIUM NITROPRUSSIDE
Authors:
Hood DD,* Dewan DM, Rose JC, James FM, Shihabi A
Affiliation:
Departments of Anesthesia, Physiology, and Pathology, Wake
Forest University Medical Center, Winston-Salem, N.C.
-
_-
-.
.-
IN GRAVID
Title:
Although sodium nitroprusside (SNP) effectively
Introduction:
controls norepinephrine induced hypertension in gravid ewes, compensatory tachycardia may necessitate using larger doses of the SNP to
control blood pressure and increase the risk of fetal cyanide toxicity.
We examined the effect of propranolol pretreatment on the dose of SNP
required to counteract norepinephrine induced hypertension in gravid
ewes.
Methods: We studied 6 chronically instrumented gravid ewes between
110 and 114 days gestation. All animals rested at least three days
following surgery. Following a control period of 30 minutes we infused
norepinephrine at a rate'of 0.32 ug/kg/min, and increased mea" maternal
blood pressure by approximately 20%. Following 5 minutes of norepinephrine infusion, we infused SNP at a rate sufficient to reduce mea"
maternal blood pressure to control levels and maintained mea" pressure
"ear control for the duration af the 50 minute experiment and recorded
the total dose of SNP infused. On the following day, we duplicated the
experiment using the same animal except we administered a 3mg
intravenous bolus of propranolol prior to the SNP infusion. Maternal
and fetal arterial blood samples were obtained during the control period,
at the start of the SNP, and after 5, 10, 20, 30, 40, and 50 minutes.
All fetal samples were replaced with a" equal volume of normal saline.
We analyzed the specimens for cyanide levels as well as blood gas
analysis and compared the data employing a multivariant analysis of
variance using repeated measures.
Results: Norepinephrine significantly reduced uterine blood flow
(DBF). SNP partially reversed this reduction but was associated with a
progressive increase in maternal heart rate. Propra"olol pretreatment
did not effect LBF but significantly reduced the maximum maternal heart
rate during SNP infusion from 149 + 4 (mean + SEM) to 115 + 8 beats per
minute (p<O.OOl). Propranolol pretreatment also significantly reduced
the dose required to reduce mea" maternal blood pressure from 5.33 +
0.24mg to 3.2 2 0.35mg (p<O.OOl). There were no significant differences
in maternal blood pressure, fetal blood pressure, or fetal heart rate
between the groups and maternal and fetal arterial blood gases remained
normal throughout both experiments.
Finally, all maternal and fetal
blood samples contained less than 50ugfliter of cyanide.
Discussidn:
Propranolol pretreatment successfully blunted the
-compensatory tachycardia associated with SNP infusion and reduced the
sodium nitroprusside dose requi.rement by 44%. We found no significant
cyanide concentrations in any blood sample. We conclude that propranolol
pretreatment safely and effectively reduces the sodium nitroprusside
requirements for correcting norepinephrine induced hypertension in the
gravid ewes.
8510
.-
._.
..
-
-
_d
_.
Title:
EFFECTS OF ISOPROTERENOL INDUCED TACHYCARDIA ON
MYOCARDIAL BLOOD FLOW AND GLYCOGEN IN THE FETAL LAMB
Authors:
Davies JM,
Affiliation:
Departments of Anaesthesia, 'Foothills Hospisal at the
University of Calgary, Calgary, Aiberta and University
Hospital, London, Ontario and of Pathology, Calgary
General Hospital, Calgary, Alberta
*1
Tweed WA,2 Alexander F,3 and Csorba T3
Introduction.
In utero tachycardia is a cause of fetal congestive
heart failure and fetal hydrops, although the mechanisms by which
tachycardia lead to cardiac failure have not been investigated.
Clinical and experimental studies suggest that myocardial dysfunction in
the asphyxiated newborn is due to a combination of insults: arteri 1
2
We
hypoxemia, myocardial ischemia and depletion of energy substrates.
therefore tested the hypothesis that severe tachycardia in the fetal
lamb causes focal or diffuse endocardial ischemia and depletion of
myocardial glycogen.
Methods. We investigated the effects of isoproterenol induced
tachycardia (IIT) on cardiac output and its distribution, on myocardial
blood flow and intramyocardial blood flow distribution, and on regional
myocardial glycogen in 8 chronically prepared, near term fetal lambs and
three control twins (for myocardial glycogen only). Blood flows were
measured by the radioactive microsphere method, myocardial glycogen by
an enzymatic method.
Results.
IIT (HR 200-280) increased cardiac output (+36%) and blood
flow to the carcass (+68%) and myocardium(+234%), while kidney blood
flow decreased (-46%). Normal intramyocardial blood flow distribution
and predominance of flow to the inner wall of both ventricles was
preserved during IIT. However, despite unchanged Pa0 and PaCO , a
metabdlic acidosis developed, which we speculate was 2 ue to lacgic acid
production by the heart. The pH shift of the oxyhemoglobin dissociation
curve resulted in a significant oxygen desaturation.
In 3 sets of
twins, glycogen was lower in the ventricular free walls of each 1IT
stressed animal than in its unstressed twin.
Discussion.
Although we were unable to provoke regional myocardial
ischemia at the maximal fetal heart rates achieved by isoproterenol
infusion, this study provides evidence for an hypothesis relating
intrauterine tachycardia and cardiac failure. Our data suggests that
acidosis, consequent arterial desaturation, and myocardial glycogen
depletion may be important pathogenic mechanisms.
We speculate that
acidosis and hypoxemia stimulate endogenous catecholamine release and
initiate a self-perpetuating process of fetal deterioration.
References.
l.Kleinman CS, Donnerstein RL, DeVore GR, Jaffe CC, Lynch DC, et al:
Fetal echocardiography for evaluation of in utero congestive heart
failure: A technique for study of nonimmune fetal hydrops. New Engl .I
Med 306:568-575,1982.
2.Lees MH: Perinatal asphyxia and the myocardium. J Pediatrics
96:675-678, 1980.
23
-
8511
._.
,-
Friday, May 10
1345
Title:
._
.~_
-
_.
.A
_.
-
. .
A NONHUMAN
PRIMATE MODELFOR STUDYINGOBSTETRIC ANALGESIA
DURING CONSCIOUSVAGINAL DELIVERY
Authors :
Golub MS,* Eisele
Affiliation:
Department
of
Research Center,
JH Jr,
Anesthesiology
University
of
JH, Line
SW
and California
California,
Davis
Primate
The rhesus
monkey (Macaca mulatta)
can provide
a
Introduction:
valuable
model for the obstetric
situation
because
of characteristics
common to primates
such as single
offspring
pregnancy,
prolonged
fetal
placentation
and uterine
morphology.
Methods
have
been
period,
developed
for monitoring
and intervening
during labor in the rhesus
monkey.
Characteristics
of labor
in seven deliveries,
four
with
meperidine
administration
and three with no analgesia,
are described.
Methods:
Pregnant rhesus monkeys were adapted
to restraint
in a
primate chair which allows a natural
sitting
position
and assumption of
postures
normally
seen in labor.
Twenty-three
chair restraint
sessions
were conducted
during
the second
and third
trimester
which included
adaptation
to bimanual rectal
palpation,
vaginal
exams, contraction
and
fetal
heart
rate monitors
and blood pressure
and temperature
monitors
and blood
sampling.
Labor was induced
with oxytocin
(1U/100ml
5%
dextrose)
when vaginal
exams using a modified
Bishop score indicated
readiness.
Meperidine
(2 mg/kg iv) was administered
2-3 hours prior
to
delivery
in four animals.
Results:
Gestation
length
at induction
was 161+6 days (term=165
days in the rhesus).
Bishop
scores
prior
to induction
were 8.0+0.9.
The final
rate of oxytocin
infusion
ranged
from 0.07
to 0.3 Ujmin.
Initial
contractions
were 2 to 20 min apart
and lasted
20 to 40
seconds.
Contractions
were 40 set to 2 rain apart immediately
prior
to
birth
and exhibited
multiple
peaks.
All births
occurred
between 1729
and 0105 hours after
labor
ranging
from 2.1-12.1
hours.
Length of
labor for the 4 demerol treated monkeys averaged
500 min as compared to
290 in the 3 monkeys receiving
no analgesia.
After
meperidine
administration,
animals did not exhibit
typical
postures
and behaviors
associated
with contraction
but sat quietly
through
contractions.
Maternal
heart
rate,
MAP and respiratory
rate increased
somewhat from
first
to last 20 min of labor
(HR 19S+l9
to 223225 bpm, MAP 7722 to
95219 Torr, respirations
3459 to 35~4 per min).
Simian Apgar scores
at
birth and 5 and 10 min postnatal
were 9.6Tl.7,
10.351.0
and 10.4+1.1
on
a 12 point
scale.
Respirations
at birth were 48+8/min in meperidine
exposed
infants
and 79+15/min
in infants
who were not exposed
to
analgesic.
Discussion:
Characteristics
of labor and delivery
in rhesus monkeys
resemble
those
in humans
in many respects.
Moreover,
standard
obstetric
monitoring
techniques
can be used.
Thus,
the monkey can
provide
an appropriate
animal model for controlled
systematic
studies
not possible
in humans due to practical
and ethical
constraints.
24
--
Anderson
8512
Friday, May 10
1400
Title:
IS THERE A SYSTEMIC
EPIDURAL FENTANYL?
CONTRIBUTION
TO ANALGESIA
FROM
8513
-,
.-
__
-
_.
-
Willatts DG and Justins DM
Authors:
Reynolds F,*
Affiliation:
Anaesthetic Unit, St Thomas's Hospital, London, UK
Vella LM,
Epidural fentanyl added to the bupivacaine test dose
Introduction.
relieves labour pain more effectively than placebo‘ or intramuscular
fentanylf Plasma fentanyl concentrations, however, were higher during
the onset of analgesia following epidural than following intramuscular
administration?
A systemic
contribution
to analgesia could not,
In the present study we have compared
therefore,
be ruled out.
epidural fentanyl with an intravenous regimen designed to produce
similar plasma concentrations in women in the first stage of labour.
Method.
In a double-dummy
trial, with the epidural test dose of
bupivacaine
lZmg, women were given fentanyl80pg
either epidurally
(n=ZO) or intravenously, 4Opg over 10 minutes followed by 40 pg over
20 minutes (n=20). Bupivacaine supplements were given when necessary
to relieve pain, which was measured by visual analogue scale at 10, 20
and 30 minutes, when plasma fentanyl was also measured. The study was
approved by the ethical committee and informed consent obtained.
Results.
Despite higher plasma fentanyl concentrations
in the
group given intravenous fentanyl, epidural fentanyl produced analgesia
which was more complete,
more rapid in onset and longer lasting.
MOreOVer, supplementary doses of bupivacaine were needed to produce
analgesia in 15 of the intravenous and only 6 of the epidural fentanyl
group (x)=6.2). Itching was noted in 8 of the epidural and in 2 of
the intravenous
group.
There were no other notable side effects.
There was no significant difference between the intravenous group and
the intramuscular and placebo groups of earlier trials, in bupivacaine
supplement requirement, duration of analgesia (time to top-up) or side
effects. Combined data are given in the table.
Conclusion.
Fentanyl 8Opg produces satisfactory
analgesia
in
labour when added to the epidural test dose, but the presence of
fentanyl in the systemic circulation makes a negligible contribution
to analgesia.
Table.
n
no. needing supplements
Combined data.
Epidural fentayl
73
17 (23%)
duration of analgesia (hours)
mean+SEM
2.25+0.09
all patients (n)
(65)
Systemic fentanyl
(imtiv) 36
25 (69%)
1.90+0.11
(32)
Placebo
33
26 (79%)
1.6620.06
(28)
References
1.
Justins DM, Francis D, Houlton PG, Reynolds F: A controlled
trial of epidural fentanyl in labour. Br J Anaesth 54:409-414,
1982.
2.
Justins DM, Knott C, Luthman J, Reynolds F: Epidural versus
intramuscular
fentanyl.
Analgesia and pharmacokinetics
in
labour. Anaesthesia 38:937-942, 1983.
25
Friday, May 10
1415
"Depth of Anesthesia" Monitoring during General Anesthesia
for Cesarian Section
-
,-
.-
-
_.
-
.-
Dafydd Thomas, FFARCS, John Evans*, FFARCS
John Radcliffe Maternity Hospital, Oxford, England
Introduction:
A pilot study has been performed to examine the use
The depth
of a "depth of anesthesia" monitor in obstetric anesthesia.
or adequacy
of anesthesia
has been monitored
by measuring
lower
Measurements
of LEC yield two
esophageal
contractility
(LEC).
principal derivatives,
the rate of spontaneous
LEC (SLEC) and the
amplitude of provoked LEC (PLEC). The responses of the lower esophagus
are predominantly
mediated
by the vagus nerve from its brain stem
nuclei and adjacent reticular activating center.
Method: Fit patients undergoing elective cesarian section have been
The investigation
was approved by the local Ethics and
studied.
Research committee
and informed consent obtained from the patients.
Anesthesia was induced with thiopentone
4mg/kg accompanied
by saxaThe lungs were ventilated with 50% nitrous oxide in oxygen
methonium.
to which 0.5% halothane was added. Ventilation was adjusted to maintain an end-expired carbon dioxide concentration
of 5%. At delivery
the halothane was discontinued and fentanyl (1.5pg/kg) was given intravenously; further increments were given as indicated clinically.
LEC was recorded from a probe positioned in the lower esophagus and
permanent recordings were made on a chart recorder. The recordings of
LEC were subsequently analyzed to examine changes associated with the
phases of the anesthetic.
Results:
The following observations were made:
1.
Lower esophageal contractility was present during light anesthesia
in the pregnant patient.
2.
As judged by the amount of LEC present, there was considerable
variation
from patient
to patient
in the response
to the
standardized
anesthetic.
Some patients had sufficient activity
to suggest that they were excessively "light", while others were
apparently too "deep".
3.
LEC was progressively suppressed during the pre-delivery phase by
the halothane but delivery was associated
with an increase in
activity.
The increments of fentanyl caused a rapid suppression of LEC which
4.
recovered
progressively
over the course of the next 20 to 30
minutes.
C onclusion:
The measurement of LEC during anesthesia may provide
the- clinician with a much needed to guide to the "depth" or adequacy of
anesthesia. In obstetric practice this may allow the anesthetic dosage
to be adjusted to an individual mother's requirements.
This would have
the advantage of:
1.
Minimizng the transfer of excess anesthetic to the fetus.
2.
Controlling the anesthetic supply so as to ensure a rapid recovery
at the end of the procedure.
3.
Ensuring
the supply of sufficient
anesthesia
to reduce the
oossibbilitv of maternal awareness.
References:
1.
J M Evans, W L Davies, C C Wise; Lower Oesophageal Contractility: A
New Monitor of Anaesthesia, Lancet 1984, 1151.
26
8514
Friday, May
10
1430
Title:
SUCCINYLCHOLINE'SACTIDN IS PROLONGED IN POSTPARTUM PATIEXTS
Authors:
BL Dowling*, TG Cheek, BB Schsntz, JB Gross, JL Apfelbaum,
H Rosenberg, BB Gutsche
8515
Affiliation: University of Pennsylvania, Phila., PA
-.
Introduction: Plasma cholinesterase (PChE) levels decrease in pregnant and
post-partum patients a.swell as in wmxn taking oral contraceptives. Since
PChE is responsible for terminating the action of succinylcholine (SCh) by
hydrolysis, one would expect SCh's duration of action to be prolonged in these
patients. We designed the present study to compare the duration of action of
SCh in post-partum patients, women taking oral contraceptives,and healthy
nonpregnant ware".
Methods: Twenty six consenting ASA I and II patients participated in this
study, which was approved by our institutional review hoard. We placed the
patients' arms in a holder fitted with a Grass ~~-10 force transducer, for
measurement of adductor pollicis strength. After preoxygeaation,we induced
anesthesia with thiopental 5 mg/kg i.v. As patients lost consciousness,we
supermaximallystimulated the ulnar nerve via surface electrodes at a
frequency of 1 Hz. We the" administered SCh 1 mg/kg while continually
recording the adductor pollicis twitch strength. When the twitch disappeared,
we intubated the patients' tracheas while maintaining anesthesia with 60% NIO
in 0,until the twitch had returned to control strength. From the twitch
strength recordings, a blinded investigatormeasured the time from SCh
administration to 25% and 752 twitch recovery, and calculated the 25% to 75%
recovery time. One-way analysis of variance and Ihxxan's multiple range test
determined the significance of differences in these variables among groups.
PcO.05 indicated significance.
Results: Duration (set) of indicated intervals after SCh 1 mglkg:
25% to 75% twitch
Iniection to 25% twitch
N
stre
strenethrecovelv
Control
14
1036
5:otio
Oral Contraceptives 7
104+8
499i29
Post-Partum
5
693&Z*
87?6
Values are means+SEx. *P<O.OOl compared with controls
Time to 25% twitch height recovery was significantlyprolonged in post-partum
patients. Further recovery, however, was not prolonged. Oral contraceptives
did not influence the recovery from Sch.
Discussion: Blitt (1) follndthat SCh's duration of action is not prolonged
in cesarean section patients. Dilution of SCh by the parturient's increased
plasma volume may explain this discrepancy. If this were true, the duration
of action of SCh should be prolonged in patients undergoing post-pa-turntubal
ligation. whose PChE levels are depressed but whose plasma volumes are
returning to normal. We observed a clinically a6 well as statistically
significant increase in the duration of action of SCh in the post-partum
state, probably resulting from decreased PChE levels. This implies that
Blitt's earlier observation at cesarean section was related to parturients'
increased plasma volumes.
Reference: 1. Blitt CD, Petty WC, Alberternst EE, Wright BJ: Correlation
of plasma choline&erase activity and duration of action of succinylcholine
during pregnancy. Anesth Analg 56:78-83, 1977.
27
Friday, May 10
1445
Title:
Authors:
PLACENTAL TRANSFER OF ATRACURIUM AND LAUDANOSINE IN THE
PREGNANT EWE
*
Mandel MB, Stiller RL, Kennedy RL, Tyler IL, Edelmann CA
and Cook DR
8516
.-
Affiliation: Departments of Anesthesiology and Psychiatry, University of
Pittsburgh, Pittsburgh, Pennsylvania
Introduction. Atracurium, a new intermediate neuromuscular blocking
agent with minimal cardiovascular side effects, is degraded by ester
hydrolysis and Hofmann elimination to laudanosine. Atracurium has a
molecular weight of 1243.4, is highly ionized at normal pH, highly protein
bound, and has a low lipid solubility. Little data are available about
the placental transfer of atracurium (1,2). We were, therefore,
interested in determining the placental transfer over time of atracurium
and its major metabolite, laudanosine, in the pregnant ewe.
125-127 days gestation, were anesthetized with
Methods. Pregnant WS,
thiamylal, their tracheas intubated, and anesthesia maintained with
nitrous oxide (60%) owgen (40%) and halothane (1%). A maternal femoral
artery and vein were cannulated. Under sterile condition a hysterotomy
was performed and a catheter inserted into a hind limb fetal artery.
Heparinized arterial blood samples were obtained from the ewe and fetus
at 1.5, 3, 5, 7.5, 10, 15, 30, 45 and 60 minutes after intravenous
injection of atracurium (0.5 n&kg) in the ewe. Samples were immediately
centrifuged, acidified, and frozen to -70°C. Atracurium and laudanosine
were subsequently assayed using a sensitive, specific HPLC method (3).
Maternal atracurium and laudanosine plasma concentration versus time
curves were fitted to a two compartment pharmacokinetic model using a nonlinear computer program. Standard macropharmacokinetic parameters were
calculated.
Results. The atracurium concentration at 1.5 minutes was 5.3 nmoles/ml.
Atracurium half-lives (aand B) in the ewe were 2.0 and 15.7 minutes,
respectively. Vl was 55 ml/kg, Vdss was 115 ml/kg and clearance 5.1
ml/kg/min. Laudanosine was detectable (2.0 nmoles/ml) in the ewe at 1.5
minutes; the elimination half-life was 25 min. No atracurium was
detectable at any time in the fetus. Laudanosine was first detectable in
the fetus at 30 minutes (0.23 nmoles/ml.). The fetal concentration
exceeded the maternal concentration at 45 minutes.
Discussion. The maternal degradation of atracurium in the relative
absence of pseudocholinesterase was quite rapid. Unlike Frank et al. cl),
we could demonstrate no placental transfer of atracurium even if fetal
plasma samples were evaporated to dryness. Likewise, Skarpa et al
demonstrated no placental transfer of atracurium in the cat. Thus', :',2,
laudanosine, a tertiary amine, seen in the fetus was of maternal origin.
Metabolites of atracurium have no teratogenic effects (2).
References.
1. Frank M, Flynn PJ, Hughes R: Atracurium in obstetric anaesthesia. Br J
Anesth 55:113-1145, 1983.
2. Skarpa M, Dayan AD, Follenfant M, et al: Toxicity testing of
atracurium. Br J Anesth 55:27-29S, 1983.
3. Stiller RL, Brandom BW, Cook DR: Determination of atracurium in pla :'a
by high-performance liquid chromatography. Anesth Analg 64~50-62,
1985.
28
Friday,
1500
L
May
10
Title:
LIMITED
HUMAN
Authors:
Warren
Affiliation:
Department
of Anesthesia,
of Medicine,
Indianapolis,
TM*,
PLACENTAL
Henry
DP,
TRANSFER
Campbell
OF METKEPHAMID
C and
Indiana
Stoelting
University
8517
RK
School
Indiana
The pentapeptide,
metkephamid,
is a synthetic
analogue of
Introduction.
Previous studies in
the naturally occurring endorphin, met-enkephalin.
human subjects have demonstrated
that metkephamid
is a narcoticlanalgesic
Furtherwith approximately
the same efficacy and potency as meperidine.
tran$fer of
more, recent data has shown that there is minimal placental
Our
metkephamid
in pregnant sheep and rats, even at very high doses.
goal is to investigate
the human placental
transfer of metkephamid.
Methods. After approval by the human research committee,
7 healthy patients at term, undergoing elective cesarean section with lumbar epidural
An epidural catheter
anesthesia
gave their informed consent to be studied.
was inserted and a test dose of local anesthetic was injected in each patient.
If no adverse reactions occurred by 5 minutes after the test dose, metkephaFour patients
mid was administered
intramuscularly
into the anterior thigh.
The remainder of
received metkephamid
0.14 mg/kg and 3 received 0.35 mg/kg.
Maternal venous blood was
the epidural local anesthetic was then given.
drawn and analyzed for metkephamid
concentration
at 30 minutes following
injection and at delivery.
Metkephamid
concentration
and blood-gas
values
in the umbilical artery and vein were measured from a doubly clamped segment
Apgar scores were recorded at 1 and 5 minutes after birth.
of umbilical cord.
Results.
The time interval between metkephamid
injection
and delivery
average 62.82
5.6 (SE) minutes.
Metkephamid
was not detected in the umbiliThe amount of metkephamid
detectable
cal cord blood in 4 of the 7 neonates.
in the umbilical cords of the other 3 neonates was small and approached
the
sensitivity
of the analytical technique.
Furthermore,
metkephamid
could only
be detected in umbilical venous blood, with an average UV metkephamid
conThe UVjMV metkephamid
concentration
ratios
centration of 93 f- 23 (SE) ngjml.
in these 3 neonates were 0.16, 0.11, and 0.11.
Umbilical
cord blood-gas
values and Apgar scores were normal in all neonates,
except one in whom a
double nuchal cord was present at delivery.
The UV and UA PO2 were 19 and 7,
respectively,
in this infant.
Discussion.
Metkephamid's
minimal placental
transfer gives it a potentially distinct advantage over other parenteral
narcotics
that are used
during pregnancy.
‘or example, the UV/MV ratio following IM meperidine
is
5
approximately
0.76.
The mechanism
that limits the placental
transfer of
metkephamid
is unknown.
Possible pharmacologic
factors include its high
molecular weight and low lipid solubility.
Placental
and/or fetal plasma
enkephalinase
activity might also play an important role.
References.
l.Bloomfield
SS, Barden TP, Mitchell J:
Metkephamid
and meperidine
analgesia after episiotomy.
Clin Pharmacol Ther 34:240-7,
1983.
Z.Frederickson
RCA, Parli CJ, Devane GW, Hynes MD:
Preclinical
pharmacology of metkephamid
(LY 127623), a met-enkephalin
analogue, National
Institute on Drug Abuse Research Monograph,
No. 43.
Edited by Harris LS,
Public Health Service, 1983. ~~150-6.
3.Moore J, McNabb TG, Glynn JP:
The p:lacental transfer of pentazocine
and
pethidine.
Br J Anaesth 45:798-801,
1973.
29
EFFECTS, PLACENTAL PASSAGE AND
CARDIOVASCULAR
PRARMACOKINETICS OF SUFENTANIL IN THE
MATERNALFETAL SHEEP MODEL
Authors:
Craft JB, Palacios QT,* Dennis L, Davis J,
Abramson FP, Stolte AL, Brsswell ME, Farina JP
Affiliation:
Departments
of Anesthesiology,
Obstetrics
and
The
George
Gynecology
and
Pharmacology,
Washington University Medical Center, Washington,
D.C.
_.
-.
-
-
-
,_.
Sufentanil
is a new synthetic opiate with a
Introduction
potency approximately
5 to 10 times that of fentanyl in humans
but is associated with a much higher therapeutic ratio. Clinical
studies in man suggest that sufentanil is associated with cardiovascular
stability
and minimal
respiratory
depression.l
Pharmacokinetic studies of sufentanil in dogs a%d humans describe
a rapid decrease in the plasma concentration
. Our goal is to
determine the effects of intravenous sufentanil on cardiovascular
and acid-base parameters, placental passage and pharmacokinetics
using the chronic maternal-fetal sheep model.
Hethods Six pregnant ewes were anesthetized with halothane and
oxygen. Under anesthesia, a Swan-Ganz catheter was inserted into
a jugular vein for continuous
CVP, PAP, CO measurements.
A
maternal
femoral
artery
and vein were
cannulated
for AP
monitoring,
acid-base
studies,
sufentanil
blood
level
determinations
and for intravenous
fluid
and sufentanil
administration
respectfully.
Bysterotomy
was performed and a
fetal carotid artery and jugular vein were cannulated
for
continuous
fetal parameters.
An intrauterine pressure catheter
was inserted and an electromagnetic flow probe was secured on a
major uterine blood vessel prior to closure.
The ewes were
allowed to recover from surgery for 24 hours prior to maternal
intravenous
injection of O.Sug/kg
sufentanil bolus with data
collection at 1,3,5,10,15,30,45,60 minutes and then at hourly
intervals up to 6 hours followed by a 24 hour determination. The
experimental data collection was repeated the following day using
lug/kg sufentanil bolus.
The order was reversed every other
week.
Results Maternal and fetalhemodynamic
and acid-base parameters appear to remain stable.
No significant
changes were
observed in heart rate, arterial pressure, pulmonary arterial
pre*sure, cardiac output, systemic vascular resistance and acidbase status at either the 0.5 "g/kg or 1.0 "g/kg dose (p>O.O5).
No significant alterations were observed in uterine artery blood
flow or uterine tone at either dose (p>O.O5). Maternal and fetal
sufentanil levels will be presented.
References.
l.Sebel PS, Bovil JG:
Cardiovascular
effects of sufentanil
anesthesia. Anesthesia and Analgesia
61:115, 1982.
2.Bovil JG, Sebel PS:
The pharmacokinetics
of sufentanil
in
surgical patients. Anesthesiology 61:502, 1984.
30
8518
_-
.-
-
-~
-
-
-
.-
Saturday,
0845
Title:
May 11
Impact of Delivery
Room Management
Outcome of Low Birth Weight Infants.
on Survival
and Long
Term
8519
Authors:
Black,
Affiliation:
Departments
of
Pediatrics,
Wayne
State
University,
Detroit,
Michigan;
University
of Colorado
Health Sciences
Center
and the
Newborn Center Denver Children’s Hospital, Denver, Colorado.
V,* Lubchenco,
LO and Butterfield,
LJ.
Survival
and outcome
of low birth weight
infants
(LBW) has
Introduction.
rapidly
improved
+ing
the past three decades.
One cause may be aggressive
While a policy of aggressive
resuscitation
of all infants is now
delivery room care.
standard
practice,
in reality
not all low birth
weight
infants
have
optimal
intrapartum
care.
We evaluated
survival and longterm
outcome of low birth weight
infants .when intrapartum
care and resuscitation
efforts
were optimal.
Methods.
We reviewed
the OB and newborn
charts of all liveborn
infants
weighing
500 to 1500 gm born from January 1, 1975 through December
31, 1978 at
the University
of Colorado
Health Sciences
Center.
Delivery
room resuscitation
was provided by a high risk team consisting
of neonatologist,
pediatric
resident and
neonatal nurse.
Intrapartum
obstetrical
care was considered
optimum if a.) the
maternal
mother
was hospitalized
during
the majority
of active
labor,
b.)
conditions
did not preclude
optimal fetal care (i.e.
eclampsia,
shock, etc.) and c.)
Resuscitation
was coded
into seven
delivery
was attended
and controlled.
Resuscitation
was considered
optimal
when the high risk team
categories.
promptly
initiated
care and no technical
problems
occurred.
Technical
problems
with resuscitation
or cases where the team decided not to resuscitate
were noted.
In the absence
of the high risk team
three similar
codes
were
utilized
for
The
final
code
was used when
a
resuscitation
by the pediatric
resident.
pediatrician
was not present until after the delivery.
Results
During the study period there were 341 livebirths
in the weight range.
Thirty infants had major malformations
and were excluded from study.
In 22 cases
the resuscitation
or intrapartum
record did not permit appropriate
evaluation.
The
remaining
289 cases were scored.
No infant weighing 500-599 grams survived.
This
group was not included in the analyses.
When prompt and technically
competent
resuscitation
was provided
(either by the high risk team or pediatric
resident)
in
conjunction
with optimal
obstetrical
care, survival
was high (75%), compared
to
that for patients
who had either delayed resuscitation
and/or less than optimal OB
care (61% p < 0.01).
In the smallest infants (600 -1000 grams) optimal resuscitation
by high risk team or resident, significantly
improved survival in all OB management
groups. (p < 0.05).
Time of neonatal
deaths was delayed
when resuscitation
was
optimal (p < 0.001).
Among the survivors optimal resuscitation
was associated
with
a significantly
lower incidence
of hyaline membrane disease (p < 0.02) and Shock (p <
0.01) but not PDA or NEC. With optimal resuscitation
58% of survivors had normal
or suspicious neurologic
examination
at follow-up.
In the remaining
group 43% had
normal or suspicious exams (NS).
Only among the smallest infants, 600-999 grams,
did optimal resuscitation
and intrapartum
OB care significantly
improve long-term
outcome p (0.02.
Discussion.
Prompt and competent
resuscitation
significantly
improved survival
when associated
with optimal OB care, delayed the time of death when infants did
succumb and reduced the incidence
of both HMD and shock among survirorr
Long
term outcoine
for the smallest
infants was improved
when optimal
intrapartum
care was provided.
References.
1. Herschel M, Kennedy J, Kayne H, Henry M, Cetrulo C: Survival of Infants Born
at 24 to 28 Weeks’ Gestation.
Obstet Gynecol 60:154, 1982.
45
Saturday,
May
11
COMPARISON
OF THE EFFECTS OF GENERAL AND REGIONAL
ANESTHESIA
FOR CESAREAN SECTION ON NEONATAL NEUROLOGIC
AND ADAPTIVE CAPACITY SCORES
_
K, David
Authors:
Nagappala
S, Abboud TK: Murakawa
Haroutunian
S, Yanaqi T
AFFILIATION:
Department
of Anesthesiology,
Los Angeles
University
of Southern California
Medical
Angeles, California 90033
S, Zakarian
CountyCenter,
8520
M,
Los
The Neonatal Neuroloqic
and Adaptive Capacity Scores
It also places
1s a new test which is easy to perform and score.
TO date
special emphasis on tests designed to evaluate passive tone.
there have been no reports in which NACS detected adverse neonatal
The present study was undertaken
to evaluate
responses to anesthesia.
the validity and the sensitivity
of the NACS examination
and also to
evaluate the effects of general and regional anesthesia
for cesarea" section on neonatal neurobehavioral
performance.
Methods:
Fifty-two neonates delivered by cesarea" section were
Twenty of the mothers received general
evaluated using the NACS.
All
anesthesia.
14 received eoidural and 18 received s"ina1 anesthesia.
mothers re&ivi"g
regiona? anesthesia were prehydrated
with 1,000 ml of
lactated Ringer's solution and were given oxygen via a transparent
face
All mothers undergoing
general anesthesia
had rapid sequence inmask.
duction using thiopental,
succinycholine
and endotracheal
intubation
followed by N 0 - 02 (4L:4L) and 0.5% enflurane until delivery of the
baby.
All mo $ hers were healthy, not in labor, and were scheduled for
elective cesarea" section.
All neonates weighed 2,500 grams or more, had
Apgar scores of 7 or more at one and five minutes and had normal acid
base and blood gas data.
Results:
Neonates delivered with general anesthesia
scored significantly lower than either epidural or spinal for some of the test items
for adaptive capacity, passive and active tone, primary reflexes and
Neonates
total scores at both 15 minutes and 2 hours of aae IP<O.O5).
delivered with epidural anesthesia
scored lower fhan those~delivered
with
spinal anesthesia
for supporting
reaction, and motor activity at 2 hours
All neonates had high scores at 24 hours by which time
of age (P<O.O5).
there were no significant
differences
between the 3 groups.
Discussion:
Findings from the present study indicate that general
anesthesia
for cesarea" section is more depressant
than regional
anesthesia
on the NACS.
Thev also indicate that the NACS examination
is
a valid and sensitive test f&eval
ating "eurobehavior&
performance
since Hodgkinson
and his co-workers Y have also found that babies delivered after general anesthesia
for cesarea" section scored lower than those
delivered after spinal anesthesia,
usinq the Early Neonatal Neurobehavioral scores.
While these findings may-have mini&l
effects on a
healthy infant, a high risk neonate may be adversely affected by general
anesthesia.
References
1. Amlel-Tlson
C, Barrier G, Shnider SM, Levinson G! Hughes SC, Stephani
SJ.
A new neuroloqic
and adaptive capacity scorlnq system for
evaluating
obstetric medications
in full-term newborns.
Anesthesiology 56:
340-350, 1982.
2. Hodgkinson
R, Bhatt M, Kim SS, Grewal G, Marx GF:
Neonatal "eurobehavioral
tests following cesarea" section under general and spinal
anesthesia.
Am J Obstet Gynecol 132:
670-4, 1978.
46
-
_.
Saturday, May 11
0915
TITLE:
THE NEONATAL NEUROBEHAVIORAL
EFFECTS
CAINE FOR EPIDURAL ANESTHESIA
DURING
OF MEPIVALABOR
8521
_
.-
,-
-
-
.-
AUTHORS:
Abboud
soraya
TK*,
M
Jacobs
AFFILIATION:
Departments
of Anesthesiology,
Obstetrics
and
Los Angeles County-University
of
Gynecoloqy,
Southern California Medical Center, Los Angeles,
California
90033
S, Murakawa
K, Sarkis
F,
Introduction:
Mepivacaine
and lidocaine which are used for lumbar
epidural anesthesia
for labor and deliver 'i, have been shown to alter
the neurobehavioral
status of the neonate .
More recently several
reports have demonst a ed the lack of adverse neonatal neurobehavioral
effects of lidocaine 5s1
The present study was undertaken
to reevaluate the neurobehavioral
effects of mepivacaine.
Methods:
Twenty healthy parturients
who elected to have epidural
anesthesia
for labor and delivery were studied.
The study was approved
by the Human Research Committee and informed consents were obtained.
All patients had internal fetal heart rate and uterine activity monitorPatients were
ing.
Epidural catheters were placed in the usual manner.
After hydration with 500
placed supine with left uterine displacement.
ml. of lactated Ringers solution in 5% dextrose, a test dose of 2 ml. of
1.5% mepivacaine
without epinephrine
was given and this was followed by
6 ml.
Further doses were re-injected
as clinically
indicated until
delivery of the infant.
Total dose was 154?17mq,
?fSE.
At the time of
delivery, blood was drawn from the maternal vein and from the umbilical
Apqar scores
vein and artery for determination
of mepivacaine
levels.
were noted.
Neonatal examination
was performed at 2 and $4 hours of
aqe using the Early Neonatal Neurobehavioral
Scale (ENNS) .
Results
for ENNS were compared to a control group of 16 babies whose mothers
did not receive any medications
or anesthesia
for labor or delivery.
Data were analyzed for statistical
significance
using Chi-square
test,
a P value of less than 0.05 was considered
statistically
significant.
Results:
Table 1 summarizes maternal and fetal plasma mepivacaine
levels.
None of the variables of the ENNS differed significantly
between the epidural group and the control group.
All babies in both
groups were vigorous at one and five minutes.
TABLE
.-
J, Kern
1
Plasma mepivacaine
levels in uq/ml (mean+SE)
Maternal vein 2.6tO.26
Umbilical vein 2.5+0.29
Umbilical artery 2.2f0.3
Umbilical vein/maternal
vein l.lkO.16
.Discussion:
Results of our study indicate that mepivacaine
as administered
in this study has no depressant
effects on the neurobehavThe hinh
ioral status of the newborn as evaluated by ENNS.
^il.. fe+al
___-blood level found in our study could possibly be due to the lower fetal
tissue wtake
of meDivacaine
pather than in&eased
olacental transfer.
Refer&es:
_
1. Scanlon JW, Brown WU, Weiss JB, Alper MH:
Neurobehavioral
Responses
of Newborn Infants after Maternal Epidural Anesthesia.
Anesthesiology 40:
112-128, 1974.
2. Abboud TK, Sarkis F, Blikian A, Varakian L:
Lack of Adverse Neurobehavioral
Effects of Lidocaine.
Anesth Analq 62:
473-475. 1983.
3. Killef ME, James FM, Dewan DM, Floyd HM:
Neonatal Neurobehavioral
Responses after Epidural Anesthesia
for Cesarean Section Using LidoCaine and Bupivacaine.
Anesth Analq 63:
413-417, 1984.
.-
47
-
Saturday,
0930
May 11
Title:
NEONATAL EFFECTS AFTER MATERNAL PROPHYLACTIC USE OF
DROPERIDOL
__
Authors
:
Edelmann
McKenzie
C,”
R
Karambelkar
D, Kennedy
R, Vicinie
A,
8522
and
.
Affiliation:
-
-
,-
-
Department
of Anesthesiology,
University
of Pittsburgh,
Magee-Womens
Hospital,
Pittsburgh,
Pennsylvania
Nausea
and vomiting
is common during
the early
phase
Introduction.
In
some
obstetric
of
subarachnoid
block
when hypotension
occurs.
patients,
nausea
and vomiting
outlasts
blood
pressure
control
by left
intravenous
fluids
and/or
vasopressors.
uterine
displacement,
Droperidol
effectively
stops
this
nausea
and vomiting
but neonatal
effects
have not been studied.
After
receiving
informed
consent
and institutional
Methods.
approval
we studied
25 healthy
full
term
unpremeditated
parturients
Patients
during
elective
cesarea”
delivery
under
spinal
anesthesia.
Patients
were
were
prehydrated
with
l-l.5
L lactated
Ringer’s
IV.
Immediately
prior
to induction
of
assigned
randomly
to one of 3 groups.
spinal
anesthesia
patients
in Group 1 (“=lO)
received
lml normal
saline
Patients
in Group
2 (n=8)
received
droperidol
0.625mg
in normal
IV.
saline
to make a total
volume
of
lml.
Patients
in Group
3 (n=7)
received
droperidol
1.25mg
in normal
saline,
total
volume
lml.
All
The range
of upper
level
patients
received
intrathecal
lidocaine,
75mg.
sensory
block
was T2-T4.
Hypotension,
defined
as decrease
in systolic
blood
pressure
> 20% preblock
level
was
treated
in
the
order
of
IV fluids
and IV ephedrine
in 1Omg
increased
left
uterine
displacement,
increments.
Incidence
of nausea
and/or
vomiting
was documented.
Apgar
No additional
scores
were
assigned
by the
pediatrician
in attendance.
medication
was given
until
after
delivery.
Two examiners,
“blind”
to
maternal
drug
administration
evaluated
and scored
the neurobehavioral
status
of
the
infants
at 4h,
24h,
and 48h using
the Neurologic
and
Adaptive
Capacity
SCOW
(NACS).~
All
babies
had Apgar
scores
of 8 or higher
at 5 minutes.
Results.
Neurobehavioral
testing
showed
no differences
among
groups
for
any
specific
test
item.
Infants
in all
groups
tended
to score
lower
at 4h
than
at 24h and 48h.
Incidence
of hypotension
was the
same
in all
groups
and responded
to usual
therapy.
The decrease
in blood
pressure
was not greater
in the droperidol
treated
mothers.
There was a decrease
in
the
incidence
of
maternal
nausea
and vomiting
as the
dose
of
droperidol
increased.
Discussion.
Preliminary
results
suggest
no adverse
effects
from
droperidol
in mothers
or neonates.
While
not
recommending
universal
prophylaxis
with
droperidol,
we suggest
there
may be use
for
this
regimen
in patients
who had unpleasant
experiences
of
nausea
and
vomiting
during
previous
spinal
anesthetics
for
cesarea”
delivery.
Likewise
droperidol
treatment
during
cesarea”
delivery
would
not
be
expected
to have adverse
effects.
Reference.
l.Amiel-Tison
C, et al:
A new neurologic
and adaptive
capacity
scoring
system
for evaluating
obstetric
medications
in full-term
newborns.
Anesthesiology
56:340-350,
1982.
48
.-
.-_
._
.-
.
.__
-
.-
Saturday,
May
11
Title:
NEONATAL
RESPONSES
TO ALPHAPRODINE
Authors:
Abboud
Aifiliatio":
Departments
of Anesthesiology,
Obstetrics and Gynecology, LOS Anqeles County-university
of Southern
;;;Zl;:ornia Medical Center, Los Angeles, CallfOrnia
TK: Murakawa
K, Yanaqi
DURING
LABOR
8523
T
Alphaprodine
(Nisentil) enjoyed widesprfad
use for
Introduction:
Neonatal
first-stage
labor pain relief for more than three decades .
.~
The present study
effects of Nisentil have not been fully established.
was undertaken
to evaluate the effects of Nisentil on the neonate when
given during labor.
Methods:
Fifteen healthy parturients
at term gestation
in active
labor were studied.
Patients were given 20-40 mq increments
of
alphaprodine
intravenously
PS needed for relief of labor pain with a
total dose of 39.3t3.7 mg (X~SEM). The study was approved by the Human
At the time
Research Committee and informed consents were obtained.
of delivery blood was drawn from a maternal vein and from the umbilical
Neonates were
cord for determination
of plasma alphaprodine
levels.
evaluated by Apqar scores at 1 and 5 min, by umbilical arterial and
and Adaptive
venous acid-base
status, and by the Neonatal Neuroloqic
Capacity Scores (NAC ) at 15 min, 2 hours and 24 hours of age as
previously
described 3 .
These results were compared to those of a group
of 15 control babies whose mothers did not receive any analgesics
or
Data were analyzed for statistical
medications
for labor or delivery.
significance
using Student's t-test and chi-square analyses when
appropriate.
A P value of less than 0.05 was considered
statistically
signiricant.
Results:
All neonates had Apqar scores of 7 or more at 5 min and
there was no significant
difference
between the incidence of low 1 min
Umbilical artery and vein acid base
Apqar scores in the two groups.
status was within normal limits in the two groups.
There was no significant
difference
in the neurobehavioral
scores
between the two
roups of neonates except for a depression
of the
habituation
to 1 7 ght response at 24 hours in the control group
(P<O.Ol)(Table).
Plasma levels of alphaprodine
will be presented at the meeting.
Discussion:
As administered
in this study alphaprodine
does not
appear to have any depressant
effect on the neonate as evaluated by
Apgar scores, umbilical
arterial and venous acid base status and "eonatal NACS.
References:
1. Kane WM:
The results of Nisentil in 1,000 obstetrical
cases.
Am J
Obstet-Gynecol
65:
1020-1026,
1953.
2. Amiel-Tison
C, Barrier C, Shnider SM. Levinson G, Hughes SC,
Stephani SJ:
A New Neuroloqic
and Adaptive Capacity Scoring System
for Evaluating
Obstetric Medications
in Full-Term Newborns.
Anesthesiology
56:
340-350, 1982.
TABLE
PERCENT
IN EACH
OF THE
Group
Adaptive
Passive
Active
OF NEONATES
WITH
FIVE GENERAL
I (Alphaprodine),
Capacity
Tone
Tone
HIGH
SCORES
CATEGORIES
Group
(2)
OF THE NACS
II (Control)
Group
15 min
1
Group
73
53
76
77
92
72
92
91
88
88
90
96
57
67
62
73
90
81
.-
2
Group
2 hrs
1 Group
2
Group
24 hrs
1 Group
Primary
Reflexes
73
82
77
77
83
83
General
Assessment
80
93
75
93
95
97
66
60
60
80
93
92
% of Good
All Tests
Scores
on
49
2
Saturday, May 11
1000
._
.
_
.-
__
-
-
._
_
-
.-~
-
.-
Title:
-PRE-PERIDURAL
Authors:
Brooks
Affiliation:
Departments
of Anesthesiology,
North Shore University
Hospital, Manhasset,
NY and Yale University,
New Haven,
GZ,*
ANALGESIA
Rafferty
TD, and
NEONATAL
Lomeli
TEMPERATURE
l.Brooks G, Lomeli G, Rafferty T:
Neonatal temperature
homeostatis
and antecedant
obstetric
anesthesia
techniques
are related
variables.
Anesthesiology
59:A400, 1983.
2.Goodlin R, Chapin J:
Determinants
of maternal
temperature
during labor.
Am J
Obstet Gynecol 143:97-101,
1982.
37.0
g
b?
Figure 1.
Pre-peridural
analgesia andneonatal
temperature
relationship.
J6.B
5
E
s
p
2
38.6
g
z
56.2
56..,
J8,0
POSTPARTUM
50
8524
G
Introduction.
We have shown that administration
of peridural
anesthesia
to the mother results in a decrease in the degree of
This
neonatal hypothermia
usually associated with delivery
(1).
probably reflects absence of maternal evaporative
heat loss from
diminution
of pain-induced
hyperventilation
and sweating
(2).
It is
not known whether pre-peridural
analgesia affects neonatal temperature.
Methods.
The reeds
of 36 neonates and their respective
mottlers
were studied.
Protocol inclusion criteria were:
healthy parturients;
amniotic membranes
ruptured<
12
uncomplicated
38-42 week pregnancies;
hours at delivery; birth weight > 2500 g; Apgar scores 7 or greater.
Infants exposed to radiant heat or maintained
in an isolette warmer
were excluded.
Neonates were classified:
1) Neonates (n=20) whose
mothers received lumbar peridural
anesthesia
(PA) (bupivacaine
0.5
percent) for labor and delivery and pre-peridural
narcotic
(alphaprodine)
administration
(APA);T
Neonates
(n=16) whose mothers
received PA without
re-peridural
narcotics.
Values were expressed
as
mean value + standar&eviation.
The two-sided Student's
t test was
used for daFa comparison.
The study fulfilled
institutional
Human
Investigation
Committee guidelines.
Results.
Total alphaprodine
administered
to APA mothers was 32.5 5
6.0 mg.
The time interval between alphaprodine
administration
and
birth of APA neonates was 5.0 + 1.7 hours.
APA neonatal temperatures
(rectal) were significantly
(P-c 0.05) greater than PD neonatal
temperatures
during the first 4 postpartum
hours (Figure 1).
This
difference
was not present subsequently
(16 hours).
Discussion:
1) The immediate neonatal period was characterized
by a
close relationship
between neonatal temperature
(O-4 hours) and
E-peridural
analgesia;
2) Neonates whose mothers received sustained
analgesia
(APA) experienced
the least derangement
in temperature
homeostatis;
3) PA anesthesia
alone did not compensate
for lack of
pre-PA analgesia;
4) the pre-PA analgesia-neonatal
temperature
association
did not extendeyond
4 hours postpartum.
*
References.
z
.-
AFFECTS
TlME
0
-
4
HDVRS
CT
Saturday,
May 11
1115
Title:
PULSE OXIMETRY IN THE NEWBORN
INFANT
Authors:
Sendak HJ. Harris
Affiliation:
Department of
Johns Hopkins
8525
AP*, Donham RT
Anesthesiology
and Critical
Care Hedicine.
Hospital,
Baltimore,
Maryland
INTRODUCTION.During the period
of transition
to an extrauterine
circulation,
the newborn infant
(NI) is in a precarious
position
in
regards
to tissue
02 delivery.
The combination
of low PaO2, high
affinity
hemoglobin,
and persistent
right-to-left
shunt, all provide
for
diminished
02 reserves
should problems
be encountered
in the immediate
newborn period.
Therefore,
for the first
several
minutes after
birth,
the continuous
assessment
of arterial
oxygenation
could be an important
Marked variations
have been reported
guide for managing resuscitation.
neonatal
arterial
in values
for cord blood SaO2,’ and intermittent
sampling usually
requires
umbilical
artery cannulation.
Pulse oximetry
noninvasive
and reliable
method of measuring SaO2 in
(PO) is a simple,
was to use PO,to measure
neonates. 2 The purpose of this investigation
Sa02 in the first
7 min of life
in infants
born by vaginal
delivery
(VD)
and cesarean
section
(CS).
METHODS. Approval was obtained
from the institutional
human investigation
committee.
PO (Nellcor
N-100) was used to measure Sa02 in 58
;;;c”,:
requiring
no O2 therapy after birth
(26 following
VD, 32 follow.
Routine post-birth
care was delivered
by a pediatrician
as
dictated
by the infants’
clinical
condition.
Apgar scores
were all E-10
None of the mothers had general
anesthesia,
but all
at 1 and 5 min.
mothers received
O2 before
delivery.
Within 15 set of birth
(cord
the PO sensor was applied
at the Achilles
tendon.
clamping),
The PO was
equipped with a recorder.
Sa02 at 60.90,
120, 150, 180, 210, 240, 300,
and 420 set after
birth
were obtained
from the strip recordings.
Data
were ana.lyzed by unpaired
t tests.
RESULTS. Sa02 measurements
were obtained
on all 58 NI. Mean SaO
increased
from 55% to 801 between 1 and 7 min after
birth
(Figure
1f .
There were no differences
between the two groups at any time interval.
CONCLUSIONS.In healthy newborns,
O2 saturation
remains low for
several
minutes following
birth.
This puts even normal newborns at
if cardiac
output should
risk for not maintaining
adequate 02 delivery
be compromised.
PO provides
a continuous
non-invasive
measurement of
of oxygenation
in the NI.
Sa02. and a means for rapid evaluation
OXYGEN SATURATION
REFERENCES
.
James LS. Weisbrot
IM, Prince CE,
et al: The acid-base
status of
human infants
in relation
to birth
asphyxia and the onset of respiration.
J Pediat 52: 379, 1958.
Deckardt R, Steward DJ: Noninvasive
arterial
hemoglobin
oxygen saturation versus transcutaneoue
oxygen
tension monitoring
in the preterm
infant.
Crit Care Med 12:935,1984.
._
Saturday, May 11
1140
TITLE:
THE EFFECT OF HALOTHANE ANESTHESIA ON THE ASPHYXIATED
FETAL LAMB
AUTHORS:
Cheek DBC,* Pytka S, Shnider SM, Parer JT, Field R,
Dailey PA, Hughes SC, Rosen MA, Levinson G, Johnson J,
Jones MA
AFFILIATION:
Depertments of Anesthesia, Obstetrics, Gynecology and
Reproductive Sciences, University of California
San Francisco, San Francisco, CA 94143
8526
In order to study the impact of maternal anesthesia on
Introduction:
the stressed fetus, we have developed a model of fetal asphyxia using
adjustable uterine artery occlusion. During induced uteroplacental
insufficiency we have studied the effects of maternal halothane
anesthesia on fetal hemodynamics and acid base status, distribution of
regional blood flow using radioactive microspheres, and fetal cerebral
metabolic oxygen consumption (CMROZ) using a chronically implanted
sagittal sinus catheter.
Methods:
Using spinal anesthesia with ketamine sedation, six ewes at
Each ewe was allowed
125-135 days gestation were surgically prepared.
to recover for 40 to 48 hrs prior to a study. After a monitored 30 min
control period, the uterine artery occlusion wire was gradually tightened
over a 30 to 60 min period to induce fetal asphyxia (pH 7.10 to 7.20;
oxygen saturation approx 30%). After 15 min a stable fetal asphyxia
(pH ? 0.03) maternal anesthesia was induced with halothane 5%,
succinylcholine 1 mg/kg i.v. was given to facilitate intubation
and then halothane 1% inspired in oxygen was administered for 15 min.
Microsphere injections were made at the end of the control period
after the period of fetal,asphyxia and after 15 min of fetal asphyxia
and halothane anesthesia.
Statistical analyses were made using a
repeated measures analysis of variance.
Results: During the three phases of the experiment (control, fetal
asphyxia, and fetal asphyxia with halothane anesthesia) there were
no significant changes in maternal blood pressure, heart rate, pH or
pco2. Maternal arterial pO2 increased significantly during anesthesia
administration with 99% oxygen. Fetal results are tabulated below:
Table (n=6)
Discussion:
Previous investigations on the effect of maternal halothane
anesthesia on the asphyxiated fetus have used umbilical cord occlusion
rather than uterine artery occlusion to induce asphyxia(l,Z) and have
produced conflicting results. Palahniuk et al reported that maternal
halothane anesthesia adversely affected the asphyxiated fetus causing a
marked reduction in blood pressure and cerebral blood flow. I" agreement
with Biehl et al, we found that halothane did not produce marked fetal
hypotension or a reduction in cerebral blood flow. Additionally, we
found that the normal fetal responses to asphyxia, i.e. increased
cerebral blood flow and reduced cerebral metabolic oxygen consumption
are not altered.
References:
1. Palahniuk, RJ et al: Anesth-Analg 59:35-39, 1980.
2. Biehl DR, et al: Canad. Anesth. Sot. J. 30:474-479, 1983.
73
Saturday,
May
11
1140
TITLE:
THE EFFECTS OF GENERAL
FETAL LAMB IN UTERO
ANESTHESIA
ON THE ASPHYXIATED
AUTHORS:
Swartz
AFFILIATION:
Department
of Anesthesia,
University
Winnipeg,
Manitoba, Canada
_
J*, Gumming
M, Pucci
W, Biehl
D
of Manitoba,
The effects of anesthetic
agents on the asphyxiated
fetus
INTRODUCTION:
General
anesthesia,
however,
are difficult
to quantitate
clinically.
is often required
in the situation
of fetal distress
to permit
rapid
This study was undertaken
to determine
the effects of Ketaminf
delivery.
Halothane
on the asphyxiated
fetal lamb.
Oxgyen, or Keramine:Oxygen:
._
._
METHOD:
Twelve pregnant
ewes of 125-135 days gestation
were surgically
prepared under halothane:oxygen
general anesthesia with controlled
ventilation.
Polyvinyl
catheters
were placed in the maternal
femoral artery
Cathand vein.
The fetus was exposed through a hysterotomy
incision.
eters were
placed
in the fetal
femoral
artery
and veiti and axillary
An occlusion
loop was placed loosely around the umbilical
cord.
artery.
The hysterotomy
was closed and each ewe allowed to recover from 48 hours
prior to study.
was performed
on the ewe,
On the day of study, a tracheostomy
followed
by a 30 minute
recovery
period.
The study began with a 30
Maternal
minute control period to ensure stability
of the preparation.
and fetal mean blood pressure
and heart rate were recorded
continuously
during the study.
Maternal and fetal blood gases were measured at reguthe production
of asphyxia,
lar intervals
during
the control
period,
and following each microsphere
injection.
After the control period the fetus was asphyxiated
by partial
occlusion
of the umbilical
cord until fetal arterial
pH had decreased
The animals
were divided
into
to 7.10-7.15
from control
(7.35-7.40).
2 groups:
Group I, received
100% oxygen and Ketamine
(3 mg/Kg) intram
venously
for induction
followed
by a second dose of Ketamine
(1 mg/Kg)
at 10 minutes
to achieve
15 minutes
of general
anesthesia.
Group II
received
an induction
of Ketamine
(3 mg/Kg)
intravenously
followed
by
Halothane
(1%) in oxygen
for 15 minutes.
Ventilation
was controlled
in both groups.
Fetal cerebral,
myocardial,
and renal blood flows wore
measured
by
injections
of
radioactive
microspheres
after
production
of asphyxia and after 5 and 15 minutes of anesthesia.
RESULTS:
The maternal and fetal cardiovascular,
blood gas, and acid-base
status were compared
to a previously
studied group of 6 ewes which received no general anesthesia
and thus served as control.
Maternal
and fetal hemodynamic
and blood gas data of the effects of Ketamine anesthesia will be presented.
REFERENCES:
Swartz
J, Gumming
M, Pucci W, Biehl D:
The effects
of
general
anesthesia
on the asphyxiated
fetal lamb in utero.
Submitted
to the Canadian Anaesthetists'
Society Journal, January, 1985.
-
74
8527
Saturday, May 11
1150
Title:
NALOXONE REVERSES PREFERENTIAL
PERFUSION
IN NEONATAL HYPOXIA
*2
BRAIN
STEM
Authors:
Lou HC,l Tweed WA,
Affiliation:
i J.F. Kennedy Institute, Clostrup, Denmark
3 University Hospital, London, Ontario
Foothills Hospital at the University of Calgary,
Calgary, Alberta
8528
Davies JM3
Introduction.
The increase in cerebral blood flow (CBF) during nepngtal
hypoxia or asphyxia is preferentially distributed to the brain ssem. ’
This may be mediated by endogenous opioid release during hypoxia and
selective depression of telencephalic metabolism relative to brain stero
metabolism.
Methods. We tested this hypothesis in five anaesthetised and
artifically ventilated newborn lambs studied during control conditions,
moderate hypoxia (arterial 0 saturation 33-65%), and hypoxia plus
naloxone (1 rig/kg). CBF was2measured by the radioactive microsphere
technique and a sagittal sinus catheter was inserted to sample cerebral
venuus blood and calculate the cerebral metabolic rate for oxygen (CMRO ).
Results. Brain stem blood flow increased preferentially during hypox?a.
The mean increase in total CBF, brain stem and telencephalic blood flow
was 442, 68%, and 43% respectively, over control. When naloxone was then
injected, CBF and CMF.02 increased further, but this further increase was
preferentially distributed to the telencephalon.
The increase in total
CBF, brain stem and telencephalic flow after naloxone was 30X, 7%, and
31%, respectively.
Furthermore, telencephalic perfusion increased
proportionally to CMR02 (r=.99).
Discussion.
This study provides evidence that endogenous opioid
depression of telencephalic metabolism is a protective mechanism during
neonatal hypoxia, permitting preferential redistribution of blood flow to
vital regulatory centres in the brain stem. Naloxone impairs this
protective mechanism, increasing CMRO, and telencephalic flow.
L
References.
l.Johnson GN, Palahniuk RJ, Tweed WA, Jones MV: Regional cerebral blood
flow changes during severe fetal asphyxia produced by slow partial
umbilical cord compression.
Amer J Obstet Gynecol 135:48-52, 1979.
2.Cavazutti M, Duffy TE: Regulation of local cerebral blood flow in
normal and hypoxic newborn dogs. Ann Neural 11~247-257, 1982.
3.l!ardlaw SL, Stark RI, Daniel S, and Frantz AG: Effects of hypoxia on
B-endorphin and B-lipotropin release in fetal, newborn, and maternal
sheep. Endocrinology 108:1710-1715, 1981.
75
Saturday, May 11
1215
Title:
THE ROLE OF 02-HEMOGLOBIN AFFINITY IN THE REGULATION
OF CEREBRAL BLOOD FLOW IN FETAL SHEEP
Authors:
Harris AP*, Rosenberg AA, Koehler RC, Hudak ML,
Tray&man RJ, Jones MD
Affiliation:
Departments of Anesthesiology/Critical Care Medicine,
and Pediatrics Johns Hopkins Hospital, Baltimore,
Maryland
8529
INTRODUCTION. Cerebral blood flow (CBF) and cerebral 02 delivery in
fetal sheep are nearly twice that in adult shee despite similar cerebral
metabolic rate (CMRO2) and arterial 02 content.? We tested the hypothesis
that this difference in CBF is due to increased hemoglobin affinity for
oxygen in the fetus by measuring cerebral hemodynamic variables before
and after increasing fetal P50 by exchange transfusion with maternal
blood.
METHODS. 12 unanesthetized fetal sheep were studied in utero. Four
days prior to study, catheters were implanted in the fetal sagittal
sinus, brachiocephalic artery, and abdominal aorta and vena cava. In 6
fetuses (shams), the effect of exchange transfusion without altering P50
was evaluated by performing exchange transfusion in the fetus with
blood from another fetus. In the second 6 animals (experimental), the
P50 was raised by performing exchange transfusion with adult sheep blood.
Both before and after exchange transfusion, CBF (using the radioactive
microsphere technique) and carotid artery and sagittal sinus O2 contents
(Ca02 and Cv02) were measured. CMR02 [(Ca02-Cv02) x CBFI, cerebral O2
delivery (OD=Ca02 x CBF), and cerebral fractional O2 extraction
[E=(Ca02-Cv02)/Ca021 were calculated. Pre- and post-transfusion data were
compared using paired t test with Bonferroni correction.
RESULTS. In the sham animals, there were no changes in any measured
or calculated cerebral hemodynamic variables except for CMR02, which
decreased 12% post-transfusion. In experimental animals, P50 was increased
by 90% post-transfusion. Ca02 decreased by 33%, but CBF was unchanged.
OD fell by 45%. CMR02 was unchanged, and therefore E increased by 77%.
CONCLUSION. After the P50 increased, OD fell and E increased. The
relative over-perfusion of fetal brain is, therefore, at least in part
due to the left-shifted oxyhemoglobin dissociation curve in the fetus,
with increased O2 affinity at tissue O2 levels. These data support the
importance of a tissue 02-dependent mechanism in the regulation of CBF.
REFERENCES. 1. Jones, Jr. MD, Rosenberg AA, Simmons MA, Molteni RA,
Koehler RD and Traystman RJ. Oxygen delivery to the brain before and
after birth. Science 216:324-325, 1982.
__
-
-
76
8530
Saturday
May
=Tjtle:
PLASMA AND CEREBROSPINAL FLUID CONCENTRAT,IONSOF
PROGESTERONE IN PREGNANT AND NONPREGNANT POPULATION.
1245
8531
Authors:
S. Datta, M.D.*, RJ Hurley, M.D., JS Naulty, M.D.,
D. Tulchinsky, M.D., GW Ostheimer, M.D.
Affiliation:
Department of Anesthesia and Reproductive Endocrinology,
Brigham and Women's Hospital, Harvard Medical School,
Boston, Massachusetts
Introduction._ A wider denaatomal spread of local anesthetic has been reported
in parturients following major regional anesthesia in early as well as late Pregnancy.l,ZObviously, the finding in early pregnancy can not be explained only by
mechanical factors, (aortic and caval compression by gravid uterus), so other
factors, including hormonal, have been suggested. We observed a more rapid Onset
and higher degree of conduction block with bupivacaine in isolated intact vagus
nerve in pregnant rabbits than in nonpregnant rabbits. We speculated that this
difference may be related to the higher plasma progesterone levels observed.3
Plasma progesterone concentration is about 60-70 times higher in parturients when
compared to the nonpregnant population. However, a literature search failed to
find any accurate measurement of cerebrospinal fluid (CSF) progesterone - specially both free and bound forms - in these two populations.
Methods. The protocol was approved by the Comnittee for the Protection of
Hummcts
from Research Risks of Brigham and Women's Hospital and informed
consent was obtained. 5ml of blood and 0.5ml of CSF were withdrawn from 12 nonpregnant individuals during the follicular phase and 28 term parturients for the
measurement of progesterone. The pregnant patients received 25% less local anesthetic to attain a comparative spread of sensory anesthesia during subarachnoid
block.
Results. All patients were in similar age group (18-38 years) and without any
,endocrinoTbgicalproblem, Proqesterone concentrations in parturients were 60
times higher in the plasma and-10 times higher in the CSF.' In plasma, 8% of progesterone remains in free form whereas 30% of free form remains in the CSF both
in pregnant and nonpregnant patients.~
Piasma
toncentrltiOn
of pwesteroneWml
C.S.F.
BO”“d
1.68 5 0.23
(n=lE)
wee
0.85 * 0.12
tionpreqnant 0.39 t .m”in=u)
0.26 + 0.01
b=7)
0.11 + .003 (n-7)
Total
3 + 0.28
(n=18)
122 L 8 (n=Zl)
2.3 + 0.6,
Free
Bound
Total
;
(n=18)
PWg”a”t
(n=,2)
115 + 11 (n=13)
1.91 + 0.71
(n-7)
13 + 1.24 (IF131
0.21 + .08 (n-7)
l !l=IMLW
**Mean~SEQiscu.5sion.Observations from clinical practice and experimental animals have
shown that during major regional anesthesia pregnant subjects require lower doses
of local anesthetics than age-matched nonpregnant controls to achieve the same
degree of anesthesia. This difference in dose requirement might not be only due
to mechanical factors or to changes in blood flow but to some direct effect of
pregnancy hormones on nerve. Our finding of increased sensitivity of autonomic
nerves from pregnant rabbits to bupivacaine as well as other published reports of
hormonal effects on smooth muscle and on mammalian and amphibian central neurons
implies that these hormones may have widespread effects throughout the matmaalian
nervous system. Our finding of ten times greater concentration of progesterone
in the CSF (30% free) in pregnant patients is significant and may be one of the
factors causing the increased dermatomal spread of local anesthetics in parturients. However, further studies are necessary to determine the exact role of this
and other hormones on the human nervous system.
References.
1. Bromage PR * Continuous lumbar epidural analgesia for obstetrics. Can
Med Assoc j'85:1136-40, 1961.
2. Fagareus L., Urban BJ, Bromage PR.: Spread of epidural analgesia in
early pregnancy. Anesthesiology 58:184-7, 1983.
3. Datta S, Lambert OH, Gregus J.: A~~f~rg~~i~16~ep~i~~~~tl~~3~f mamaalian
nerve fibers during pregnancy.
Sunday, May 12
0815
_-
,-
Title :
2-CHLOROPRCCAINE
FOR LOCALPERINEALINFILTRATION
Authors:
Philipson,
Affiliation:
Department of Obstetrics
and Gynecology, Cleveland
Metropolitan General Hospital/CWRU, Cleveland, OH.
EH, Kuhnert, BR, Syracuse,
8532
CD & Kaine, CJ
Introduction.
Local infiltration
of the perineun is ccmmonly performed
Recently lidocaine,
the most commonly
to provide analgesia for episiotomy.
used agent for local perineal infiltration,
was found to rapidly cross
the
placenta
and result in significant
fetal exposure (1).
Lidocaine and its
2active metabolites
persisted in neonatal urine for at least 48 hours.
Chloroprocaine,
an ester-linked
local
anesthetic
agent,
may be a more
appropriate agent for local perinatal infiltration
because
of its
rapid
However, it is rarely used for this
metabolism
to inactive
metabolites.
procedure.
The purpose of this study was to determine
1) then disposition
of 2-chloroprocaine
in mother fetus and neonate following local perineal
infiltration,
and 2) if 2-chloroprocaine
is appropriate for this procedure.
and their infants
were studied.
Methods. Nine normal term parturients
After
local perineal infiltration
with 1% 2-chloroprocaine
for episiotomy,
its
the
concentrations
of
2-chloroprocaine
and
metabolite,
2chloroaninobenzoic
acid (CABA) were quantitated in maternal plasma, in the
and in maternal and neonatal plasma for 48
umbilical cord vein at delivery,
hours after
delivery.
Plasma levels of 2-chloroprocaine
were quantitated
by gas chranatography/mass spectrcmetry;
CABAby gas chrcmatography.
Results.
At delivery,
2-chloroprocaine
was nondetectable
in maternal
and umbilical
cord vein of 8 patients;
1 patient had trace levels in the
cord.
Chloroprocaine was not detectable
in neonatal plasma, but CABA was
Mean levels of CABAin
detectable
in maternal
and cord vein plasma.
maternal plasma at delivery were 1.04 +-O.32 ug/ml and mean levels
in cord
vein were 0.35 f 0.54 ug/ml.
These levels of CABAare approximately half
those found after
epidural
anesthesia
for vaginal
delivery
(2).
The
clinical
results indicated that 2-chloroprocaine
provided good analgesia.
Discussion.
that
The results
indicate
very
little,
if
any,
pharmacologically
active
drug reaches the fetus following local perineal
infiltration
with 2-chloroprocaine.
Therefore, 2-chloroprocaine
appears to
be preferrable
to lidocaine when used for local perineal infiltration.
References.
1.
Philipson EH, Kuhnert BR, Syracuse CD: Maternal, fetal
and
lidocaine
levels
following
local
perineal
infiltration.
Obstet. Gynecol. 149:403-407,
1984.
2.
Kuhnert, BR, Kuhnert PM, Prochaska AL, et al.:
Plasma levels
of 2chloroprocaine
following epidural anesthesia in obstetric
patients and
their neonates.
Anesthesiology
53(1):21-25,
1980.
__
81
neonatal
Amer. J.
Sunday, May 12
0830
Title:
LIDOCAINE DISPOSITION FOLLOWING SPINAL ANESTHESIA
Authors:
Philipson EH,
Kuhnert BR,*
Syracuse CD and Kaine CJ
Pimental R,
8533
Kuhnert PM,
Affiliation: Department of Obstetrics and Gynecology, Cleveland Metropolitan General Hospital/CWRU, Cleveland, Ohio
J&roduction.
It is the general impreslocal
that
concentrations of
sion
pl_*sun
L,DOC&II,E
LEVELS
FOLLOVI(N(I
anesthetic in maternal plasma never reach a
SP,NlLANESTHESIA
FORDELlYER”
level that can possibly affect the fetus
^ 1omr
ID”‘mGv
following spinal anesthesia[l]. HOWWL?r,
this
has never been verified by measuring 5
.: .
.
.
.
.
drug levels in maternal or neonatal body c
CO,d
“.,”
fluids. Recent studies in nonpegnant sub- : 100.'..
. cord.,1.1,
jects suggest that in some cases, drug lev- '$ .
els may reach those found after epidursl u
anesthesia[Zl. The purpose of this study g
was to document the disposition of a local
TIME
(M,"",.,,
anesthetic agent, lidocaine, following spinal anesthesia in maternal, fetal and neonatal body fluids.
Methods. Lidocaine and its two active metabolites were quantitatad by
sensitive gas chromatography/massspectrometry techniques. Plasma concentration time curves, fetal/maternal ratios, and neonatal elimination
were determined in ten patients and compared to what has been previousiy
reported following the use of lidocaine for epidural anesthesia.[3]
.&sultg. Considerable levels of lidocaine are found in maternal
plasma.
The figure represents a typical patient who received 75 mg of
lidocaine (1.5 cc of 5%) for cesarean section. Data suggest that individual peak maternal plasma lidocaine levels may be similar to what is
found after epidural anesthesia. Hbwever, mean levels are l/3 those
found after the higher doses used for epidural anesthesia. Peak levels
occur later than following epidural anesthesia. Mean fetal/maternal
ratios were 0.37kO.2 and mean cord artery/cord vein ratios were 0.5k6.7.
Discussion. These results~verify that significant plasma levels of
lidocaine occur following spinal anesthesia in obstetric patients even
though very low doses of anesthetic are used. Furthermore, considerable
levels reach the infant.
Thus, this study suggests that spinal
anesthesia with lidocaine should be considered similar to any other
anesthetic technique in that it may result in considerable neonatal drug
exposure.
References.
1.
2.
.-
3.
Shnider SM, Levinson G: Anesthesia for obstetrics. Williams &
Wilkins Co., Baltimore, P. 114, 1979.
Giasi RM, D'Agostino E, Covino BG: Absorption of lidocaine followSubaracMoid
and epidural administration. Anesth Analg
=x3
58:360-363, 1979.
Kuhnert BR, Knapp DR, Kuhnert PM, et al.:
Maternal, fetal, _ I. _
neonatal metabolism of lidocaine.
Clin Pharm Ther 26:213-2ioT
1979.
82
Sunday,
May
12
0845
Title:
DECREASED CSF PROTEIN DURING PREGNANCY AS A MECHANISM
FACILITATING THE SPREAD OF SPINAL ANESTHESIA
Authors:
Sheth AP.* Dautenhahn DL, Campbell SB, Fagraeus L.
Affiliation:
Department of Anesthesiology,
University of Oklahoma
Health Sciences Center, Oklahoma City, Oklahoma.
8534
Introduction. Hormonal, chemical, as well as mechanical changes have
been implicated to explain increased potency and facilitated spread of
local anesthetic in epidural and subarachnoid spaces during pregnancy.
In this study CSF samples of pregnant, postpartum and non-pregnant
patients were studied for total protein concentration which could affect
the action of local anesthetics.
Methods.
The study was approved by the committee on Human Research.
One ml CSF was collected before injecting local anesthetic for spinal
anesthesia from 12 non-pregnant women between 20-40 years age group
(control), 12 early pregnant patients between 12-17 weeks of pregnancy,
22 term pregnant patients
for elective
C-section,
50 postpartum
patients.
CSF samples were analyzed for total protein content by a
DuPont Automatic Clinical Analyzer #3.
All CSF samples studied were
clear and patients with medical problems were excluded.
All pregnant
and postpartum groups were compared with the control group utilizing
analysis of variance followed by unpaired t tests.
Discussion.
The
temporal
Results.
See Figure
CSF
pattern
of
orotein
cYmo.rll(r*wrcu,
reduction in early pregnancy,
? "1
term pregnancy and early postpartum
match
temporal
the
period
of
pregnancy
related
increase in potency of local
anesthetic.
Inspite of the low
concentration of protein in CSF
compared to blood, the small
volume of distribution rn the
subarachnoid
space
and
the
regional anesthesia technique
used may influence the dissociation of local anesthetic significantly in spinal anesthesia by:
(1)
Decreasing buffer capacity.
Local anesthetics are salts that
need buffer to convert to the base form (active form) for transport
across membranes.
Decrease buffer capacity may allow local anesthetic
to remain salt for a longer time giving time to spread further
increasing dermatomal spread.
It will also increase time to complete
analgesia.
(2) Decreased binding. More unbound active form of local anesthetic
will be available for blocking action in subarachnoid space.
Also,
since the protein binds to the unionized portion of local anesthetic,
decreased protein levels would increase local anesthetic potency.
Conclusion.
Decreased protein concentrations in CSF increase local
anesthetic potency by affecting buffering, binding and ionization of
local anesthetic agents in the CSF.
8535
introduction:
Recent studies have reported decreased matrxnl ?I? ,-ln<:
<TO: in 1.abcrir.gparturients after the administration of 111~bar epidural~
acalgesia.
?o ascertain if these ventilator!/ effects were secondary to
effects of *rhe pharmacologic aprr.ts OII the WC~W,
or if the-e effects
were secondary to relief of pain, the following study was undertake?.
This study was conducted under the guidelines and wjth the approval oc
the University cf Pennsylvania Committee on Studies 1nvolvi.n::Punan
Subjects.
Methods:
Six patients who were to undergo elective CFS~TE~" sectiorm
before the o"sft of l~hor were the subjects of this study. The patiwtr;
rrcejved no premeditation.
After obtaining informed consat,
hasel?"c
CE, irO2, and CC02 measurements were obtained with continuous indirect
calorimetry.
Measurcnents were recorded after patients had attail1l.i
steady state, which WC judged to be present by the stability of ventj-latnry and wtabolic
parameters, apd by stability of the percentage of
carbon dioxide in the expired air. Ccntrol measurements were obtainer‘
for s minimum of 10 minutes.
After the administration of lumbar ep~idurzl block tr? R minimum sensory l,evel of Th, with a mea" of 26.7 (? 1.7
SEMI ml.. cf 1.5% lidccaine ("=4), 3% ?-chloroprocaine ("=l), or 0.55:
bupivacaine (I=?), repeat ventilator) and metabolic meas"rer:e"ts were
obtained fcr 10 minutes.
Using each patient as her own control, no ntatlstically
Results:
significar~t difference was see" in the wan
CE, +OZ', or GCO? in the
entire group of pntirnts after onset of epidrlral analges!~.
-
before block (ml/min/kg)
after block (ml/n;-:n/kg)
mean (~SEM)
mean !TSFM)
i'E
86.7
(6.5)
98.9 (8.5)
irn2
3.0 (0.3)
3.1 (0.3)
oco2
2.1 (0.2)
Z.? (0.2)
Discussion:
In parturirnts serving as their own controls during the
first stage of !nbor, Hager?nl~ et al. showed that do2 decreased 'ram 4.4
ml/min/kg to 3.1 ml~iminlkg and GE decreased from 195 mlimjnfkg to 1C;
nlfminfky following the initiatio" o.f epidural block.
Our <1,xtawould
suggest that the decrease in CE and WY? cbservcd Ian the laborirp part,irient after the administration OF epidural annl~gesia is secondary to
rrlief of pain ,z"d not a" intrinsic pharmacologic effect of thcce
anesthetic agents on the parturient.
Reforerces:
1. -&erdal,
M., Morgan C.T.J., Sumner A.E., Cutschr , P.F. : virlllr~
ventilation an? oxygen consunption during labor wit'? epidura7 znnlgesia.
Anesthesiology 59:47-49, 1483
7. Sangoul, F., Fox, C.S., Houle G.L.: Effects rf regional, analgesia ~7
maternal oxygen consunptio" during the first stage of labor.
Arm. .J.
Ohstet. Gyn. 1:1:1080-1083, 1975
84
Title:
INTEGRITY
OF EPIDURAL
Authors:
Lachica
Affiliation:
Departments
R,*
Santos
Introduction.
the catheter
of removing
cause
the
Broken
laminar
of
broken
Touhy
tip
identification
of
threaded
through
A
catheter
epidural
10 cm.
catheters
Wild
mm
have
and
by
a different
placement
with some
Heerbrugg
photographed
Ltd.,
using
Teflon
CH-9435,
of
the
Eastman
Kodak
Co.,
the
scanning
electron
mechanism.
tip; the withdrawal
of
resistance
throughout
epidural
Areas
attrihuted
at the
Kodak
were
photo
the
of
Results.
Kinks
and
evidence
a further
and
a range
col.or film
resolution
ETEC
abrasions;
3
noted
and
were
of the
ski-like
effect,
greater
obviously
grossly
longitudinal
broken
ETEC
The
material
1.
2.
of
leaving
References:
Bromage
some
PR:
Epidural
catheter
Analgesia.
Crawford
JS, Williams
ME,
space.
Brit J Anaesth
47:807,
by
WB Saunders
Vales
1975.
I
S:
a 35
6-32x
and
Corporation,
thr
streaks
camera.
naked
like
ski
eye.
tracks
nicks;
35 showed
suggestive
of cuts
SEM
catheters.
teflon
catheter
were unmistakably
tracks streaking
over the surface
as noted by Crawford2
in his case report,
area
where
it can provoke
symptoms,
with
of
as
were
Outfit
revealed
through
the Makroskop
were
tip of the Touhy needle
abrading
can occur
the needle
consequence
Curity
55 Polaroid
superficial
of nicks,
Conclusion.
Damage
to epidural
catheters
the needle
over
the catheter
especially
if
However,
a critical
IlectZssXy.
the
used
viewed
through
the Makroskop.
streaking
type of indentation,
and l-2
number
as indentations
by the Huber
of
2483, PCF
135~.36,
was achieved
using
Aut.oscan,
greater
extent
when
56 showed longitudinal
what
appeared
craters
formed
catheter.
Slivers
the longitudinal
were
by
was
the
from
the
catheter
breakage
experiences,
equipped
through
micrography
Still further
cuts
of kinking
from
a torque
degree
of damage
with
deeper
when
successful
labor
and delivery
Photomakroskop
Switzerland,
magnified
formations,
to a much
examined,
unequivocally
that
actually
microscopic
over the
alongside
obvious
shoulder-hump
were made evident
Of the 94 catheters
brittle
tip
needle
entire
supplied
catheters,
Rochester,
NY.
microscope
(SEMI
the
the
actual
these
anesthesia
for
WILD
M400
Heerbrugg,
interest
After
3392 Investment
Blvd.,
Haywood,
CA, equipped
with PN Type
The catheters
were coated
with gold-palladian
film for SEM.
Indentations,
to
needle
of the Touhy
needle,
the catheter
resistance
noted
in passing
through
kits,
obtained
after
epidural
via
the
dissecting
microscope,
magazine.
been
shearing
occurred
which
resulted
in
As a result
the distal
end.
studied
in great detail.
Ninety-four
prepackaged
examined
4,
case
from
were
University
to ret,hread
the catheter
instead
together
as a unit.1
Yet
another
I:t is the same
shearing
at
observed.
recently
achieved
beyond
the needle
with
considerable
similar
Methods.
was
but
8536
N
during
an attempt
and the catheter
the epidural
the needle
needle
and 3 ems.
catheter
was met
length.
catheters
catheters,
catheters
needle
R and Ruebusch
STUDY
Ohio
knotted
back
needle
A DETAILED
and Pathology,
Cincinnati,
epidural
pincer,
is pulled
both
the
Bendon
of Anesthesia
of Cincinnati,
catheters,
DJ,
CATHETERS:
noted
of the
in the course
of removing
has some
imperfections.
in
the
patient
is unknown.
if the foreign
material
operative
intervention
Co.,
Particulate
springing
catheter.
occupies
may he
1978.
matter
in
the
extradurnl
Title:
-
DEXTROSE IN ANESTHETIC
SOLUTIONS AND
ITS RELATIOil TO EPIDURAL ANESTHESIA
Authors:
Egerman,
l&l*, Mawji,
F, and Joyce
Affiliation:
Department of Anesthesiology,
College of Medicine,
Houston,
8537
TH
Baylor
Texas
Introduction.
Many factors such as age, height, pregnancy,
position,
and volume, and concentration
of local anesthetic
appear to influence the
Dextrose has been empirically
spread of solutions
in the epidural space.
added to epidural anesthetic
solutions to speed the onset of perineal
anesthesia
in pregnant patients at the time of delivery, or to improve
patchy or unilateral
neural blockade.
Methods.
We will compare differences
in the levels and dermatomal
spread of neural blockade and quality of analgesia
using dextrose containing anesthetic
solutions
for continuous
lumbar epidural anesthesia
during active labor.
In 50 patients for whom epidural anesthesia was
chosen for labor analgesia,
dextrose containing
solutions were given to
23.
Lumbar epidural anesthesia was performed
in the lateral decubitus
Bupivicaine
diluted with 10;' dextrose with
position in the usual manner.
the concentration
of 0.202 and a specific gravity of 1.015 at 37O c or
bupivicaine
diluted with normal saline with the concentration
of O.ZOY:
and specific gravity of 1.007 at 370 c were administered
in a double
blind fashion.
The patients were placed in a semirecumbant
position
with a left tilt within 3 to 5 minutes of the initial injection.
HYPOalgesia to pin prick and loss of temperature
discrimination
were used
to determine
the levels of sensory and sympathetic
blockade.
Subjective criteria for pain relief were ranked on a scale of 0 to 4 with 0
being no relief of labor pains and 4 being complete relief of pain.
Results.
Differences
between the study group and control group were
statistically
insignificant.
There were no differences
in the lowest or
highest level, or dermatomal
spread of neural blockade, when using
heavier anesthetic
solutions.
The subjective
analgesia
score was also
similar in both groups.
Discussion.
There are many variables that can be manipulated
to
change the quality and location of neural blockade using the epidural
technique.
Some, such as volume and concentration
of anesthetic
solutions, as well as site of epidural puncture, are the most important facbe n purtors governing anesthetic
spread.
Gravity and position have
7 Our
ported to affect the spread of fluids within the epidural space.
findings are not in agreement with others2 who found that dextrose in
chloroprocaine
solutions resulted in significantly
lower levels of
blockade.
Dextrose added to epidural anesthetic
solutions
in attempt
to augment gravitational
effects has minimal effects on the spread of
anesthetic
solution in the epidural space.
Also, it has no discernable
effects on the resulting quality of neural blockade.
References.
1. Brolnage PR:
Spread of analgesic solutions
in the epidural space and
their site of action:
A Statistical
Study.
Brit. J. Anesth.~:;:l,:1-7_,1_'~:1
2. Park YR, Eastwood DW:
Dextrose effects gravitational
spread of
epidural anesthesia.
Anesthesiology
52:
439-441,
1980
Sunday,
May
I2
0945
8538
litle:
Authol:s:
Affi,liation:
.-
.._
_-
-
This study was designed co determine
tl?e efficacy~ ok lidct.~.:.irc
in
Introduction.
various Concentrations
for continuous
epidural infusion and tr determint wl;cther
high volumes of low concentrntjons
were more effectiT:e than lnw volumes ui lligh
concentration
as we observed with hotb chloroprocaine
and bupivacaine
(I:nr!sthesiology 53:S296, 1980 and 59:A40;, 1983).
:iiltlli:;study
Methods.
Twenty-two
consenting ASA I and I: patient:, pzrticipnted
Cpidural
ciithctcrs were
which was approved by cur institutional
revjew board.
interspace
and tht patients
w'frc nursed
in
uniformly
positioned
ir the J,.
3-4
semisupine
position
with L.lJ.0. A pilot study showed I"/ !~j~docninc xas inadeAl!. subsequent
patients
received
a 2rc
quate to establish
the initial block.
test dose followed hy a 1Occ loading holus of 1.5% lidocaine
and were issigned
randomly to a grcup (see chart) to receive a continuous
lidocaine
infusion over
dictated
study
the next
135 minutes
unless
inadequate
analgesia
or delivery
terminaticn.
Pain, temperature
motor block and cubjectivc
annlgesiz
sensation,
were
evaluated
at
?O-minute
intervals
during
the first I~our and the], zt 3Cminute intervals.
Results.
Series 1 (see tilb!~e)contained seven patients in four groups (J,2,?,4)
receiving a lidocaine
infusion rate of 70 mg/hr (O.25%, 0.5%. 1.0%) or 35 clg/hr
Kevicr: of this series
(.25%) after an initial
12cc dose of 1.5% l~idocaine.
showed this dose to he 'inadequate for contiwous
infusicp~ due to insufficient
dermatome coverage, patchy spread of analgesial
x?d/or the presence oC cre-si~ded
blocks (analgesia
limited to the down side only).
In series 2 ( rce t;iblej theconcentration
of lidocaine
infusion was increased
to 105mglhr
(Croup A 1.50%;
OrCUp H 0.75%; GrOUp c 0.375%) Or 52.5",g/hZ (croup U 0.375%).
This stildy grcup
to date consists
of 11 patients.
It was apparent
that grcup A did 1,r.thave
clinically
adequate analgesia.
While groups B, C and D had twperature
blcckade
of an adequate number of dermatanes,
these iniusions
of ljdocaine
did not consistently produce adequate analgesia
for labor.
niscussion.
Preliminrry
results indicate that low conicr?trations of l~idocaine
infused
at high volumes
(0.375:; at 28ml/hr)
provide
more effective
~nalgesla
than that of high ccncentrations
infused zt low vo:lur;es (1.5% at Jcc/hr).
men
compared
to a 20mg/hr infusion
of hupivacaine,
blocks maintained
n-it!) IOSmg of
lidocaine were "spotty" and less satisfactory.
Thee additirr; c,f epineJ.l!rine to
the lidocaire
so.lution or the u.se of larger volunle:; could p?.csil)ly remedy this
problem.
The stlldy is ongoing, further results will he presented.
Table.
Croup No. % Lidoc.
ml/hr
r?g/hr
n~ernatomes
Remark::
Rlocked
series 1
1
I
14
0.25
35
Range
Me,lr.
!-- 'nadequctl
?
2
0.25
28
70
2- in:3f?eollate
1
3
0.50
14
70
!- Inadeqate
3
4
7
1.0
70
3:nc&?w
Series
2
A
B
c
D
2
6
2
I
1.5
75
:375
.375
7
!L,
28
14
105
105
105
52.5
5-13
9-20
12-15
14
9th
II'-&
I 1.i:
2.. l~nnd~?<,u;!te
1- Inal:::,G<::s
I- 1r;i:rquate
Sunday,
1030
_-
-
-
i”lay 12
Title:
CQNTINUOUS
DELIVERY
Authors:
Pierce
Affiliation:
Department
of Anesthesia,
Medicine,
Cincinnati,
Ohio
ET*,
EPIDURAL
Demon
DD,
ANALCE:S:A
and Santos
F&1
iA30R
A.\13
DS
University
01: Cincinnati
College
Of
Introduction:
We recently
reported
the pharmacokinetic
data on continuous
epidural
infusions
achieved
by a single loadin, or dose (IO cc of 0.5,?6) of bupivacaine
followed
by a continuous
infusion
of 0.0625% at 20 cc/hr
during labor in term
parturients.
In that study, 50% of the patients
required
additional
50 rng bolus of
0.5% bupivacaine
to produce adequate analgesia for delivery.
In an effort to avoid the need to supplement
for perineal
anesthesia,
we doubled
the effect
of
the hourly dose fro:n 12.5 mg to 25 mg. We also wanted to evaluate
infusion volume on pharmacokinetics
and extent
of neural blockade.
(Methods: Twenty
term parturients,
ASA I or II, admitted
in labor for vaginal
delivery
were randomly
assigned
to one of two groups.
After
a lumbar
epidural
catheter
was placed,
they received
a 10 cc bolus of 0.5% bupivacaine
over five
An IVAC pump was then
used to deliver
a continuous
infusion
of
minutes.
Group 1 received
0.125%# at 20 cc/hr
and Group II
bupivacaine
in normal
saline.
received
0.25% at 10 cc/hr.
Blood samples (3 ml) were (drawn through
an 18 gauge
After
intravenous
catheter
every
15 minutes
after
the start
ore the infusions.
delivery,
postpartum
maternal
and venous cord blood samples
were obtained
before
the infusion
was stopped.
Bupivacaine
was measured
using a double extraction
technique
and gas chromatology
(I).
This study was approved
by the Institutional
Review
Board for Human Research
and each patient
signed an informed
consent
form.
Results:
Two patients
were eliminated
frown each group because
the infusion
had to be stopped
and/or
the patient
underwent
cesarean
section.
Additional
boluses of 4 cc of 0.5% were required
for one patient
in Group I and three patients
in Group II. Postpartum
(final) maternal
concentration
for Group I (0.125%)
ivas
0.81 f 0.21 pg/ml and for Group II (0.25%) was 0.79 + 0.31 ug/rnl (N.S.).
Fetal
maternal
concentration
ratio for Group I was 0.27 f 0.13 and for Group II was 0.23 ?
0.12 (N-S.).
Discussion:
In this study, a 50 mg bolus followed
by a continuous
infusion of 25
mg/hr
of bupivacaine
provided
75% of the patients
with adequate
analgesia
throughout
labor and delivery.
The postpartum
levels were not significantly
higher
and the fetal-maternal
ratios
were significantly
lower than those in the previous
study which used 12.5 mg/hr.
These findings
suggest
the higher dose of 25 rngihr
provides
better analgesia
without risking significant
accumulation
or toxicity.
Although
the two infusion
rates
resulted
in comp,xable
maternal
and fetal
serum
leves, Group I (0.125%
at 20 cc) required
fewr
additional
boluses than
Group
II (0.25%
at
10 cc) and Group
1 tended
to have
higher
derinatomal
involvement
suggesting
that a higher infusion rate enhances
the depth and spread
of analgesia.
References:
1. Denson DD Knapp RM, Turner P, Thompson
GA: Serum bupivacaine
concentrations in te&
parturients
following
continuous
epidural
analgesia
for labor and
delivery.
Ther Drug ~Mon 6:393-398,
1984.
8539
Sunday
May 12
Title:
LIDOCAINE
LEVELS DURING CESAREAN SECTION AFTER
PRETREATMENT
WITH RANITIDINE
OR CIMETIDINE
8540
1045
Authors:
Dailey PA,*, Hughes SC, Rose" MA,
Pytka S, Fisher DM, Shnider SM
Healy
K, Cheek
DBC,
Affiliation:
Department
of Anesthesia,
Obstetrics,
Gynecology,
of California,
Reproductive
Sciences, University
Francisco,
California
and
San
Introduction.
The routine "se of cimetidine
prior to cesarea" section has been recommended
to increase gastric pH and reduce gastric
has been shown to alter the
juice volume.[l] However, cimetidine
in
hepatic clearance of lidocaine, probably due to a decrease
hepatic blood flow and inhibition of the liver microsomal
cyto-
.-
_
-
,-
-
-
.-
,-
chrome P-450 system.[2]
Ranitidine
does not appear to alter
hepatic clearance of lidocaine.[3]
This study compares
the effects
of cimetidine
and ranitidine
on maternal
lidocaine blood levels
during epidural anesthesia
with lidocaine for cesarea" section.
Methods.
Following approval of the Committee
on Human Research and
informed consent, patients scheduled for elective cesarea" section
with epidural anesthesia
were randomly assigned
to one of three
groups: I="o H2-antagonist
150 mg PO at least
(n=3); II=ranitidine
2 h
before anesthesia
(n=5); and IiI=cimetidi"e
300 mg IM at least
All groups received sodium citrate 30
1 h before anesthesia
(n=5).
ml PO within one h of anesthesia.
After placement
of a" epidural
catheter, all patients received 25 ml of lidocaine 2% with
epinephrine
1:200,000 injected over approx 5 min. Whole venous
blood samples for lidocaine levels were obtained prior to lidocaine
administration,
at frequent intervals
thereafter
for 4 h, and at
delivery.
Arterial and ve"o"s blood samples from a doubly clamped
segment of umbilical cord were collected
for lidocaine levels and
umbilical
cord blood gas analysis.
The neonate was evaluated by
time-to-sustained
respirations
(TSR),
APGAR scores, and "eurobehavioral
exams.
Results.
Patients who received cimetidine
had significantly
higher
lidocaine levels than patients who received ranitidine at 12,L5,
and 18 min after epidural administration
of lidocaine.
The mea"
peak blood level for patients in Group I was 2.10 k 0.41 "g/ml;
Group II, 1.55 + 0.32 "g/ml; and Group III, 3.03 + 0.54 "g/ml.
The
highest lidocaine level measured was 4.80 ugiml and occurred at 21
min in a patient who received cimetidine.
The pharmacokinetic
analysis has not been completed.
There were no significant
differences between groups in umbilical
cord lidocaine
levels, lJV/MV
lidocaine concentration
ratios, APGAR scores, TSK, fetal acid-base
status, or neurobehavior
scores.
Discussion.
Lidocaine
levels were significantly
higher in patients
who received cimetidine
versus ranitidine.
In some patients who
received cimetidine,
lidocaine levels approached
those commonly
associated
with toxicity, although no adverse side effects related
to lidocaine were observed
in the mother or neonate.
Based on
these preliminary
results, we conclude that ranitidine may be the
preferred H2-antagonist
for premeditation
to decrease gastric acidity and volume prior to epidural anesthesia
with lidocaine.
References.
1. Moir DD:
Anesthesiology
59:81-83,
1983. 2.
Feely
.I et al:
Ann Int Med 96:592-594,
1982.
3.
Feely J, et al:
Br J
Clin Pharmacol
15:378-379,
1983.
Sunday,
May
1~2
1100
._
,-
_
-
-
-
-
-
.-
.-
Title:
A CLJNICAL STUDY OF THE EPIDIIRAL USE OF pti AlrJIISTFI)
RUPIVACAINE
IN PARTURIEMTS
Authors:
McElorland GH,*
Affiliation:
Department of Pharmaceutical
Department of Anaesthesia,
Sciences, The University
of British Columbia, Vancouver,
British Columbia
Douglas
MJ,
Robertson
K, Ross
PL, Axelson
8541
JE
In 1960 Coder reported
that a longer duration
of action
Introduction.
for intercostal
nerve block resulted
from the addition of dextran to the
local a0esthetic.I
In 1979 Rosenblatt
reported
that the pH of dextran
The
40 might be the mechanism
for increasing
the duration
of action.2
of
block
from
local
effect
of
pt; change
on
quality
and
duration
anest$etics
was confirmed
hy Galindo
and Witcher,
both in vitro and in
With approval
of the Ethics Committee
on Human Experimentation,
vivo.
a double blind study was undertaken
to examine the effect of epidural
pH
adjusted hupivacaine
on labor pain.
Informed consent was obtained
from laboring
parturients
who
Methods.
A lumbar
epidural
catheter
was
were
requesting
epidural
analgesia.
inserted at L3-4 and then either bupivacaine
0.25% plain or pH adjusted
The pH adjusted
bupivacaine
was freshly
bupivacaine
0.254 was injected.
made by the addition of 0.1 cc of 8.4% sodium bicarbonate
to 20 ml of the
A test dose of 3 ccs was given followed by 5 ccs of the
local anesthetic.
local anesthetic.
The time of the test dose was taken as zero time.
The
Immediately
after
the
observer
was
blinded
to
the
solution
used.
sensation
was tested using
administration
of the test dose, temperature
Fifteen
ice at L1 and onset time was determined
by a change
to ice.
minutes after the test dose, a venous sample was obtained for hupivacaine
analysis.
Time of the first painless contraction,
height of the block to
ice and time of regression
of the block 2 segments was also measured.
pH
of the test solution was measured using a digital pH meter.
Results.
To date 18 cases have heen studied:
7 in the control group
The pH of the plain hupivacaine
ranged
and 11 in the pH adjusted group.
from 5.39-6.58
(mean 5.8), and that of the pH adjusted
bupivacaine
from
7.16-7.38
(mean 7.28).
The onset time in the control
group ranged from
4 to 8 minutes
(mean 6 minutes 13 seconds)
and in the pH adjusted
group
from
1 minute
45 seconds
to 4 minutes
15 seconds
(mean 3 minutes
7
seconds).
Further results will be presented.
Discussion.
Local anesthetics
are thought to he most effective when
there
IS
more
unionised
base
present.
The
unionised
base
is most
effective in crossing the nerve membrane to produce the anesthetic effect.
An increase in pH of a local anesthetic
will result in an increase of the
unionised
fraction of the drug.
In our study, onset time for effect of
the local anesthetic
appears to shorten when the pH is adjusted to hecome
more alkaline.
References.
l.‘loder RE.
A local anaesthetic
solution with longer action.
Lancet 1960
2:346-7.
Z.Kosenhlatt
RM, Fung DL.
Mechanism
of action
for dextran
prolonging
regional anesthesia.
Regional Anesthesia
1980; 5(2):3-5.
3.Galindo
A, pH-Adjusted
local anesthetics:
clinical
experience.
1982
Annual meeting
of American
Society
of Regional
Anesthesia
(Abstract)
Sunday
May
1115
-
-
-
-
11
TITLE:
THE LETHAL DOSE
AND NONPREGNANT
OF INTRAVENOUS
RABBITS
AUTHORS:
Eisler
Dailey
AFFILIATION:
Department
of Anesthesia,
University
of California
San Francisco,
San Francisco,
CA
94143
EA,* Baker
PA, Hughes
BUPIVACAINE
IN PREGNANT
W, Shnider SM, Halpern SH, Levinson G,
SC, Rosen MA, Johnson J and Jones MJ
Cardiotoxic
reactions from accidental
intravenous
Introduction:
injection of bupivacaine
appear to occur more frequently
in obstetrical
changes
patients.(l)
If this is so, it may be that the many physiologic
that occur during pregnancy make the parturient
more susceptible
to the
We investigated
this
cardio-depressant
effects of bupivacaine.
hypothesis
by constructing
dose response curves for the lethal dose
of bupivacaine
in pregnant and nonpregnant
rabbits and determined
the
LD50 for each group.
We studied unanesthetized
rabbits rendered acidotic
and hypoxic to simulate the acidosis that occurs during local anesthetic
induced seizures in humans.
Methods:
Under halothaneloxygen
anesthesia
catheters were inserted into
femoral arteries and veins of 45 nonpregnant
female rabbits and 35
pregnant rabbits.
After recovery from preparatory
surgery, animals were
given a mixture of air, CO2 and nitrogen to breathe until arterial pH
was between 7.12 and 7.18 and Pa02 was 10 to 20 torr below control.
The
rabbits received an intravenous
dose of 0.5% bupivacaine
over 10 sec.
Five animals were studied at each of a variety of doses ranging from
1.0 to 2.8 mg/kg.
Continuous
ECG and arterial pressure traces were
monitored
for the first 5 min following injections.
Dose response curves
were constructed
by plotting mortality
(%) against dose using the
method of Litchfield
and Wilcoxin.(2)
Results:
The LD50 of a bolus dose of bupivacaine
was 1.62 in
nonpregnant
rabbits and 1.59 in pregnant rabbits (figure).
These were
not significantly
different.
The slopes of the two lines did not differ
significantly.
Discussion:
Morishima
et al found that in pregnant versus nonpregnant
sheep, lower doses of bupivacaine
were required to produce cardiovascular
depression
and circulatory
collapse.(3)
We found that the plot of
bupivacaine
dose against mortality
in acidotic rabbits produces a very
steep curve that is not modified
in
position or slope by pregnancy,
that is
the LD50 is not changed by pregnancy.
..-..
MO”
P1.ql.“l
00 o-D sl.ln~“<
Our results suggest that the increased
frequency of cardiotoxic
reactions seen
00
in obstetrical
patients may not be due to
.a
an increased sensitivity
of pregnant
z 10
patients to bupivacaine
cardiotoxicity.
:w
Other factors such as increased likelihood
of accidental
intravascular
injection or
increased difficulty
in resuscitation
may be responsible.
References:
1. Albright,
GA:
Report to the FDA,
October.
1983.
2.
Litchfield
JT, Wilcoxin F:
J Pharmacol
I
,; I,," 20 10 1~01~0
Il__
IS,
~"sl"lcI,*L
1949.
Exp Ther 97:99-113,
3.
Morishima
HO et al:
1983.
59:A409,
Anesthesiology
92
8542
__
Sunday, May 12
1125
TITLE:
._
SUCCESSFUL RESUSCITATION AFTER MASSIVE INTRAVENOUS
BUPIVACAINE OVERDOSE IN THE ACIDOTIC RABBIT
AUTHORS:
Cheek DBC: Pytka S, Shnider SM, Dailey PA, Rosen M,
Hughes SC, Levinson 6, Johnson J, Jones MA
AFFILIATION:
Departments of Anesthesia, Obstetrics, Gynecology
and Reproductive Sciences, University of California
San Francisco, CA 94143
8543
._
.-
_
-'
._
-
-
_
_
.-
-
.-
-
-
._
Rapid intravenous bupivacaine administration to
Introduction:
acidotic rabbits has been shown to cause cardiovascular collapse
and death, with an LD50 of 1.6 mg/kg.(l)
This study was
undertaken to investigate resuscitative techniques after massive
We studied unanesthetized rabbits
i.v. bupivacaine administration.
rendered acidotic and hypoxic to simulate the asphyxia that often
occurs during local anesthetic-induced seizures in humans.
Methods:
Nineteen rabbits underwent halothane/oxygen anesthesia
for insertion of two femoral artery catheters, a femoral vein
catheter and application of surface wires for EKG monitoring.
Animals were allowed to recover from preparatory surgery for at least
two hours. Animals were then placed in an airtight chamber and given
a mixture of air, C02, and nitrogen to breathe until arterial pH was
between 7.12 and 7.18, and Pa02 was lo-20 torr below control. Then
all rabbits were given bupivacaine i.v. over 10 set and resuscitation
was initiated within 30-60 sec. Group I (n=9) received bupivacaine
2.4 to 3.0 mgjkg and were resuscitated with oxygen and CPR alone.
Group II (n=lO) received bupivacaine 3.0 to 6.0 mg/kg and were
resuscitated with oxygen, CPR, intravenous epinephrine and bicarbonate.
Epinephrine was given in bolus amounts of 20 fig/kg at 60 set, then
repeated at 30 set intervals to maintain a mean blood pressure within
50% of control; sodium bicarbonate was given in doses of 1 mEq/kg
at 60 set, then again when base excess was less than -5 mEq/L.
Continuous ECG and femoral arterial pressure tracings were recorded
and arterial blood gases obtained every Z-10 min. Animals were
considered survivors if after 30 min of resuscitation they had sinus
rhythm and a stable blood pressure.
Results: After intravenous injection of bupivacaine all animals
seized within 30 set and had serious cardiac rhythm abnormalities,
particularly wide QRS complex bradycardia or tachycardia, AV
conduction blocks, electromechanical dissociation, and/or asystole.
In Group I, with oxygen/CPR resuscitation, there was a 56% survival
rate. In group II, using much larger bupivacaine doses all animals
survived. The average total dose of epinephrine necessary for
resuscitation was 90 pg/kg, but the doses required ranged from 30&g/kg
to 200 fig/kg.
Conclusion: We found that immediate resuscitation with effective CPR
together with bicarbonate and very large doses of epinephrine are
necessary to treat bupivacaine cardiotoxicity.
The dosage of epinephrine
required appears to be much larger than those usually considered standard
for cardiopulmonary resuscitation.
Reference:
1. Eisler et al:
Anesth Analg 64:209, 1985
-
93
Sunda Y,
1135
-
May
12
Title:
Magnesium
Potentiates
the Cardiac
Authors:
Spielman FJ: Carter
Mueller RA
Affiliation:
Department
of Anesthesiology,
Chapel Hill, NC
27514
LS, Saltzman
Toxicity
of Rupivacaine
LS, Norfleet
University
CA, Corke
of North
8544
SC,
Carolina,
Introduction.
and bupivacaine
(Ru)
are
frequently
Magnesium
(Mg)
Roth
Mg and
Bu have
negative
administered
to preeclamptic
patients.
chronotropic
and inotropic properties
(1,2).
We investigated
the cardiac
effects of these drugs in the isolated rat heart.
Sprague
Hawley rats
were heparinized
and
anesthetized
with
Methods.
ether.The
hearts
were rapidly
excised, arrested
in iced
saline and
attached to
a Langendorff
apparatus.
Krebs-Henseleit
solution
(KHS) ,
02 95% and
CO2 5% at
37c
constantly
perfused
the
hearts.
A
balloon
systolic and
catheter was
inserted into
the left ventricle
to measure
diastolic
pressures
(LVSP, LVDP) and heart
rate (HR).
After a 20 minute
stabilization
period the
hearts were randomized to a KHS
with 2.4 Meq/L
Mg (control
group, N=6)) or
6.4 Meq/L Mg (high
Mg group, N=6)
for the
remainder
of
the study.
Subsequently
each
heart was
perfused
with
increasing concentrations
of Bu;0.5, 1.5 and 2.5 ug/cc for
10 minutes at
each concentration.
Hemodynamic
parameters were measured at baseline and
nata
is reported
as
at
10 minutes
after
each
drug administration.
x + SEM and was analyzed using analysis of variance.
Eesults.
The HR
decreased
significantly
more in the high
Mg group as
compared to the
control group (Fig.).
There were
minimal and transient
decreases
in LVSP and LVDP in both groups.
Buoivacaine
UQ/CC
,.I,.5_...
'21.5
l.....
*
-
k
._
TIME
Minutes
w
pso.01
**p<o.o01
from control
-
-
Discussion.
In the isolated rat heart Mg and Bu have additive negative
chronotroplc
effects.
These
results may be clinically
relevant for the
preeclamptic
patient receiving both Mg and epidural analgesia with Ru.
References.
l.Shine KI:
Myocardial
effects of magnesium.
Am
J Physiol 237:413-23,
1979.
.~_
2.Tanz
RD,
Heskett
T,
Loehning
RW,
Fairfax
cardiotoxicity
of
bupivacaine
and
lidocaine in the
mammalian
heart.
Anesth Analg 63:549-56,
1984.
,~_
94
CA:
Comparative
isolated perfused
Stmday,
May 1.2
1200
-
-
-
-
-
-
c
Title:
CONTINUOUS
INFUSION OF EPIDURAL
OPERATIVE PAIN RELIEF FOLLOWING
Authors:
Skerman
Affiliation:
Obstetrics
and G.yneco1og.v.
Departments
of Anesthesiology,
State
Shreveport,
Louisiana
School
of
Medicine
in
University Medical Center, Shreveport,
Louisiana
JH,
Gupta
A,* Jacobs
FENTANYL
CESAREAN
MA, Goldstein
FOR POST
SECTION
MT, and Rlass
8545
NH
Introduction.
Continuous
infusion
pumps
have
for some years
been
accepted
as an useful adjunct
in the administration
of epidural anesthesia for relief
of pain and to provide
better
physioloaic
conditions
epidural
administration
of
narcotics
has
Similarly,
during
1ahor.l
become an accepted means of pain relief post cesarean section.2
For patients where epidural anesthesia
has been indicated and
Methods.
the
usual
and
customary
anesthesia
chosen
for their cesarean
section,
levels have been achieved
with the local anesthetic
of choice prior to
Upon the completion
of surgery
the epidurdl
commencement
of surgery.
catheter
is retained
in place
and upon the return of motor
function
(patient is able to move her feet and bend her knees), she is riven a
After 20
bolus of fentanyl
50 pg
diluted
in lnml of normal saline.
minutes
a continuous
infusion
of fentanyl
5 fig/ml
in normal
saline
is
started
using dn Abhott Life Care Micro
Infusion
pump dt
the rate Of
The extent of sensory analgesia
lOml/hour through the epidural catheter.
is determined
b.y pin prick
sensations
and this level is modified
hy
raising or lowering the volume infused/hour.
Of the patients
receiving
this therap.v to date, only one
Results.
incidence
of slight pruritis
has been seen; no evidence
of respiratory
depression
has heen observed
and no patient
has experienced
nausea
or
Pain relief has been extraordinary
with no patients
in the
vomiting.
medications
during
the
post
study
requiring
any
further
parenteral
surgery period prior to discharge.
Urinar.y retention is not a prohlem as
Foley catheters are left in place for 24 hours.
Discussion.
Epidural injection of fentan.yl as a controlled
continuous
infusion through the catheter appears to provide superb pain relief post
cesarean delivery.
No patient has received fentanyl infusion longer thdn
The advantages
of this technique to both patient and obstetri20 hours.
cian
are that duration
of pain
r lief is readily
controllable;
side
effects
such as might
be expected.ec - pruritis,
nausea
and vomiting,
urinary
retention
or
depression
somnolence
are
respiratory
and
A further inestimable
advantdqe
comparatively
minimized
or non-existent.
is that the patient is able to ambulate far sooner than exoected.
At our
institution,
we have had instances
where
the patient
has been ahle to
walk from the Recovery Room to her room on the ward wheelinq her infusion
pump stand in the company
of a nurse.
Early
amhulation
lessens
the
possible formation of adhesions,
deSCredSeS
or
even eliminates
flatulence
and makes for a very comfortable,
happy mother.
References.
l.Kenepp
NR,
RR:
Continuous
infusion
Gutsche
epidural
block
for
analgesia
in labor. Anesthesioloqy
59, 3:A406, 1'983.
Z.Rosenblatt
RM, Davis H: Continuous
epidural
infusion
for obstetrical
analgesia:
A preliminary
feasibility
study. Req Anesth 5:19-30, 1980.
3.Nault.y JS,
Johnson
M, Burqer
GA, Datta
S, Weiss
JB,
i+rrison
.I.
Ostheimer
GW:
Epidural
fentanyl
for
post
cesarean
delivery
pain
management.
Anesthesiology
59, 3:A415, 1983.
Sunday,
.-
May
12
1215
Title:
PROPHYLAXIS AGAINST ACID ASPIRATION DURING GENERAL ANESTHESIA
IN OBSTETRIC PATIENTS: A COST-EFFECTIVENESS ANALYSIS
Authors:
Koren MJ* , Fineberg HV, Ostheimer GW
Affiliation:
Department of Anesthesia, Harvard Medical School and
Harvard School of Public Health, Boston, Massachusetts
.-
._.
-
-
Intraoperative aspiration of acid gastric contents is an
Introduction.
important cause of morbidity and mortality among obstetric patients underIn recent years, many investigators have suggested
going general anesthesia.
means of chemoprophylaxis against the consequences of acid aspiration.
This
study compares the cost-effectiveness of three strategies of prophylactic
neutralization of gastric acid against a baseline of no prophylaxis.
-
Methods. The strategies compared in this analysis were (1) the liquid
antacid, 0.3M sodium citrate or its equivalent, (2) the histamine-2-receptor
antagonist, cimetidine, and (3) 0.3M sodium citrate and cimetidine combined.
Elective cesarean deliveries and patients presenting in labor were analyzed
Probabilities and pertinent cost estimates were derived from
separately.
the literature and from a review of the hospital experiences of a cohort of
patients treated for acid aspiration at several teaching hospitals. Sensitivity analysis to determine the robustness of our results included a
Monte Carlo simulation.
.-
._
.-
.-
In the case of elective cesarean deliveries, cimetidine or
Results.
sodium citrate alone reduced expected mortality by 90% and resulted in
overall cost savings compared to no prophylaxis.
Cimetidine and sodium
citrate combined decreased mortality to virtually nil with an incremental
cost-effectiveness ratio of $130,000 per life saved as compared to antacids
alone.
For the laboring population, sodium citrate alone was both more
efficacious and less costly than cimetidine and, compared to no intervention,
reduced mortality by 90% at a cost of $57,600 per life saved. Sodium citrate
and cimetidine combined further reduced mortality but, at the great incremental cost of nearly $40 million per life saved.
Discussion.
We conclude that prophylaxis, using agents in combination,
is mstified
for elective cesarean patients. Sodium citrate alone
appears appropriate for women arriving in labor. The results of a Monte
Carlo analysis suggest that our findings are pertinent to practicing anesthesiologists in a wide range of clinical settings.
.-
._
96
8546
Sunday,
1230
_
-
-
,-
-
May 12
Title:
PATIENT-CONTROLLED
ANALGESIAFOLLOWINGELECTIVE CESAREAN
DELIVERY
Authors :
Bolden
Affiliation:
Department
University
M,* Pate1
of
of
R, de la Vega S, McKenzie
8547
R
Anesthesiology,
Magee-Womens Hospital,
Pittsburgh,
School of Medicine,
Pgh.,
PA
relief
of pain following
cesarean
Traditionally,
Introduction.
delivery
(CD) has been accomplished
by administration
of intramuscular
Less
than optimal
pain management
occurs
due to under
narcotics.
treatment
resulting
in inadequate
analgesia
and over treatment
producing
Patient-controlled
analgesia
excessive
sedation,
nausea
and vomiting.
(PCA) circumvents
these problems by self administration
of intermittent
We compared the efficacy,
small
intravenous
doses of analgesic
agents.
side effects,
patient
preference
and dosage
requirements
of PCA vs IM
morphine analgesia
in 40 patients
following
elective
CD.
The project
was approved
by institutional
review
and all
Methods.
Excluded from the study were patients
patients
gave informed
consent.
with history
of smoking, alcoholism,
chronic
analgesic
use,
drug abuse
CDs were performed with lidocaine
spinal
and major or current
illness.
Morphine
sulfate
(MS) 0.075
mg.kg-’
anesthesia
without premeditation.
PCA patients
was given
IV after
delivery
to provide
an analgesic
base.
(Abbott
Laboratories)
were instructed
to use the Lifecar I@ PCA Infuser
for use in the recovery
room and until
the IV infusion
was discontinued.
Control
patients
received
MS lo-15
mg as necessary
every
three
hours.
At 4h intervals
we recorded
narcotic
usage,
degree
of sedation,
pain
and pruritis
utilizing
linear
relief,
and incidence
of nausea, vomiting
scales.
Patients
recorded
their
subjective
pe’rception
of these same
parameters.
PCA patients
who had previous
CD were asked to indicate
their preference.
Results.
Preliminary
data reveal
little
difference
in mean total
MS
usage between control
and PCA groups
over the first
16h postoperative
period.
There
was a large
standard
deviation
in individual
MS
requirements.
More sedation
and higher
pain scores
occurred
in the
control
group.
Nausea, vomiting and pruritis
tended to be higher in the
PCA group.
All patients
in the PCA group described
their pain relief
as
adequate.
PCA patients
having
a repeat
section
preferred
PCA to IM
injection
except
one who expressed
no preference.
Several
control
patients
were dissatisfied
with their
pain relief.
Mean duration
of
Foley catheter
placement and time to spontaneous
voiding
were similar.
Discussion.
Previous
studies
with PCA involving
surgical
patients
have indicated
a high degree of patient
acceptance
and efficacy
of pain
relief.‘*’
Reports of side effects
including
nausea, sedation,
pruritis
and respiratory
depression
in patients
using PCA have been variable.‘pz
In Our study
there
was no case of respiratory
depression.
Nausea,
Vomiting
and pruritis
were mild and no patient
was withdrawn from the
PCA study ‘group.
PCA appears
to be an efficacious
and safe
method of
providing
post cesarean
pain relief.
References.
l.Bennett
R, et al:
Patient-controlled
analgesia.
Ann Surg
195:700-705,
1982.
2.Tamsen
A, et al:
Patient-controlled
analgesic
therapy:
Clinical
experience.
Acta Anaesth Stand Suppl 74:157-160,
1982.
97
Sunday,
1245
May
12
Title:
MUSICTHERAPYDURINGREGIONALANRSTHRSIA
Authors:
Noel TN,’ Kovach AM
Department of Anesthesiology, University of Utah,
Salt Lake City, Utah
Introduction. Proponents of music therapy have claimed that mUSiCcan
decrease anxiety and pain, and reduce requirements for supplementary
medications in patients having surgery under regional anesthesia. Most of
these claims have been anecdotal in nature, and those studies known to this
investigative team have suffered from poor design, poor technique, or both.
This study is an attempt to address these questions with rigorous controls.
Methods. After approval by the Institutional Review Board and informed
consent, 30 patients scheduled for elective repeat cesarean section were
randomly assigned to three groups--music therapy, white noise therapy, and
no therapy. The patients were trained pre-operatively in the use of visual
analog scores (VA9 for reporting subjective pain and anxiety. An
anesthesiologist, unaware of the patient’s group assignment, performed an
epidural anesthetic with the agent of his choice, and was instructed to
administer diazepam for anxiety or restlessness, or fentanyl for analgesia, as
he felt indicated Data collected Included VAS pre-operatively and at three
specified points in the procedure, as well as the amounts of each medication
received. Statistical analysis of the data was performed using BMDPlDand
BMDP7Dsoftware as converted for use on the DRCPDP-11 computer.
Results. Analysis confirmed no statistical difference between the groups
in age. weight. height, duration of procedure, or pre-operative VAS. Music
was found to be more effective in reducing anxiety than white noise or no
therapy.(p<.OfiI No significant differences were observed in subjective pain
scores reported or amounts of medication received.
Discussion. For those situations in which it is desirable to avoid the use
of pre-operative sedatives or anxiolytics, such as cesarean section or
ambulatory surgery, music therapy can provide a more stress-free milieu.
The operating team is free to discuss intra-operative findings without
concern for disturbing an awake patient; the patient is isolated from the
anxiety-provoking surgical noises, and the occasional indelicate comment,
that are part and parcel of the operating room environment.
References.
1. Melzack R. Pain Measurement and Assessment. New York: Raven Press,
1983: 33-37.
2. Naido A. Music Sedation for Local Anesthesia. Anaesthesia 1976;3 1:300301.
Affiliation:
-
.-
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-
-
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-
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8548
Title:
EFFECT OF SPINAL ANFSTHESIA
FETAL CATECHOLAMINE
RELFASE
FOR CESAREAN
SECTION
ON
Authors:
Abboud TX: Yanagi T, Murakowa K, Kern S, Soraya M,
Haroutunian S, Zakarian M, Artel R
Affiliation:
Departments of Anesthesiology, Obstetrics and GyneC"logy? r,"o nnqnl~ea county-university of Southern
California Medical Center, LOO Mgeles,
Colif0rni.o
8549
pre~i"u~ reports have shown that epidural analgesia durIntroduction:
ing labor and elivery decreased matefnal circulating catecholamlneo but
had no effect on fetal catecholamincs
, which ore important for better
The prenent study
neonatal adaptation t" the cxtrnutcrinc cnvironmcnt.
woo undertaken to evaluate the affect "f opinal nnenthenia for ceoeresn
section on fetal catecholamine release.
Methods: Twenty-one healthy women at term gestation, not in labor and
The oturly woo approved by
och&%ZeTfor
ceoarean section were otudicd.
the Institutional
Review Hoard and informed conoento were obtarned
from
Group I pnticnto (n-14) rwcived
spinal oncntheoia
uoing
all patients.
tetracaine.
Group II patients (n=7) served as a control and received
eneral anesthesia
usinq rapid sequence induction Collowcd by N2O-02
9 4L:4L) and 0.5% enflurane until delivery of the baby.
venous blood was ohtni~ned from an indwellinq
At time of delivery,
venous catheter in the mother and from the umbilical vein and artery of il
doubl
clamped section oE the umbilical cord Eor determination
oE
catec x olamine levels and blood gao and acid be%? atntun.
Data were analyzed for statistical
significance
using Student's
t-teat
and Chi-oqunrc when npproprinte.
A P v;l111nof <n.ns wns conoiaerra
statistically
significant.
Rcoults:
All nronatco had Apqar scoreo oE 7 or more at 5 min and norPlasma norrpinrphrtnc
(NH) and cplnrphrlne
(Ht
melXc?ase
status.
levels did not differ significantly among the two groups for the maternal
vein (MVI. Umhilicel vein (UV) and umbilical arter
(WA1 NE and E levels
tended to be higher in the o inal anesthesia group E ut the difference did
not reach ntntinticnl ntqn<~F
P cnnc~ (fiqurrn).
Discussion:
Fetal cntecholnmlncn hnvn been nhown to promate wonntnl
adaptation
to the extrauterine
cnvironmcnt
as evidenced
by increase in
cardiac performance,
atimu ati.on of lung liquid nhnorption
and enhnncnment of surfactant release 1 .
Findings from our study indicate that spinal
anesthesia
for cesarean section did not alter the fetal catecholamine
response.
These findinos are in anreement with those ~reviouslv
renorted
using epidural anesthesia
for labor and deli"eryI~
~In'the present 'study
maternal catecholamines
did not decrease after spinal anesthesia.
The
1,atter finding is also in aqreement with previous report
in which spinal
a,neOt esia did not decrease maternal catccholamines
in patients not in
labor 9 .
This selectivity
suggests that the mechanism
by which catecholo-
mines decrease after spinal anesthesia is related to relief of maternal
pain.
References:
bb d TK, Yanagi T,
CoogIndi J, Aenriksen
EH: Effects of epidural analgesia during
labor on fetal plasma
catechalamine release.
Annstheeiolagy 61,
A413, 1984.
2. Lawson Et%, Brown ER.
Tordny JS, Modnnsky DT.,
Taeusch fiW:The effect
1.
of e inephrine on
trac Kes1 fluid flow
and surfactant efflux
in fetnl sheep. Am
Rev Resp Dis 118: 10231026, 197R.
3. Abboud TK, Artal R,
Henriksen EH, Earl S.
Knmmula RR: Erfectl
of spinal anesthesia
on matern.31 circulating catecholnmines.
Am J Obstet Gynecol
142; 252-254, 19R2.
_
8550
ABSTRACTS NOT PRESENTED AT MEETING
99
Title:
Authors:
Affiliation:
PROLONGED BLOCKADE WITH VECURONIUM
IN THE TUBAL
LIGATION PATIENT
Tessem J,* Jones MM, Longmire S,
Adenwala J,
Joyce TH
Department
of Anesthesiology,
Baylor College of
Medicine, Houston, Texas
In four consecutive
patients vecuronium
Introduction:
O.lmg/kg
produced
prolonged
greater
than
1.5 hours
and
irreversible
at 80 minutes
(5mg neostigmine
and 2.5 mg of
atropine) neuromuscular blockade.
With Institutional Review Board approval, ten ASA
Methods:
Premeditation
"as cimetidine
300mg
I patients were studied.
orally at 0600 and metaclorpramide
1Omg IV 20 minutes prior to
During preoxygenation
Fenranyl 2uglkg "as given 5
induction.
A peripheral
minutes before thiopental
3mg/kg for induction.
nerve stimulator (Fischer and Paykel A-300) over the ulnar nerve
recorded baseline train of four and throughout the procedure.
Vecuronium O.lmg/kg was injected intravenously.
Results:
The trachea was intubated at 90%+ depression
of twitch which
Anesthesia "as maintained with
occured in 140 (120-180)seconds.
70% Nitrous Oxide and Oxygen with fentanyl
1OOug added to
maintain a sleep or drowsy patient after removal of the nitrous
oxide.
Return of 25% of twitch occured in 63 (35-102) minutes
with sustained head 1iEt in eight non-reversed
patients in 96
Patients 9 and 10 were reversed
with
2.5mg
(56-119)minutes.
of neostigmine
and 1.2m.g of atropine at 25% return of twitch
height at 102 and 57 minutes respectively.
Complete reversal "as
easilyaccomplished at this dose of neostigmine in patient number
in 5 minutes in patient number 10.
HOWeVer,
9 and
repeated
the delayed
return to 25% of twitch height
in all cases
represents
a 2-2.5 time increase
in the duration
of the
neuromuscular
block
from duration
reported
in nonpregnant
patients.
Discussion:
In these postpartum
patients Ear tubal ligation
Vecuronium
took on the appearance
of its predecessor,
pancuronium,
Although
endotracheal
intubation conditions were
excellent in all case*, the long duration of recovery to 25% of
twitch and/or sustained headlift "as excessive for this short 30+
10 minute procecdure.
If relative non-reversability
is present
until 25% return of twitch occurs, vecuronium at O.lmg/kg appears
to be contraindicated in this patient population.
References:
1.
Uurant NN, Katz KL: Non-neuromuscular efEects oE vecuronium
and other competitive muscle relaxants in clinical experiences with norcuron.
Excerpta Media, 1983.
2.
Clarke RSJ, Mirakhur RK: Intubating conditions after vecuronium; a study with three doses and a comparison with suxamethonium and pancuronium.
Ibid, 1983.
Agoston S: Clinical pharmacology of vecuronium; a prelim3.
inary report on a multicenter
study in 800 patients. Lbid,
1983.
4.
Nagashina H, Kaplan R, Yun H, et al:
Clinical pharmacology
0E vecuronium; a comparison with pancuronium, 1983.
5.
Fragen RJ, Shanks CA: Vecuronium in Outpatient surgery. 1983
8551
Title8
Authors:
LABOR-DELIVERY-RECOVERY ROOM: Design, application
and experience in private practice.
8552
Belonsky, B.L.1 Emralin0,Q.E.; Kuchling,A.;
Loon,M.; Nalone, R.
Affiliation:
Department of Obstetric Anesthesia, Good
Samaritan Hospital Cincinnati, Ohio.
Introduction: There have been competing values in obOn one hand
stetric care over the last several decades.
a rapidly advancing technology has produced progressive
improvement in the outcome of pregnancy; on the Other
a groundswell of interest in the childbirth
Facilities in the traditional labor-delivery
to be a hinderance to both objectives.
The static atmosphere of the labor room is not conducive
t0 a family oriented birth while the carpeted birthing
room has inadequate space and equipment and is illsuited to
unanticipated operative delivery or the management,of any
significant maternal or early neonatal complicaticn.
Method: A report will be given as to hov
proposed by basler, Hager and Tienprasic
combined labor-delivery-recovery room has been used at our
hospital for the last 2 years with very gratifying results.
Approximately 5000 deliveries occur per year with continuous
epidural anesthesia being administered to 93% of patients,
both for vaginal delivery and Caesarean sections. This
experience has been of great value in assessing the effectiveness
of this type of facility under all circumstances of obstetric care both complicated and uncomplicated.
Results: The results have been gratifying from the public
acceptance of the concept and from the complete obstetric
care that has been offered to the patients.
lnie
will present data on all types of cases and discuss both the advantages and disadvantages of this type of facility with
suggestions on how it can be implemented in any obstetrical
unit.
_~
_
References: 1. Schmidt, Richard, T.F.: Labor-Delivery-Recovery Room; Planning the delivery suite for current
10:49-59, 1983.
need. Clinics in Perinatology
2. Basler, D.;Hager,D; and TiLnprasid,N: Alternatives for
Obstetric Design, Ross Laboratories, 1980.
-.
_
102
_
8553
Title:
Authors:
Affiliation:
VECURONIUM FOR POSTPARTUM TUBAL LIGATION
Camp C,* Jones M, Adenwala
J, Longmire
Rodriguez V, Joyce TH
Baylor
Department
of Anesthesiology,
Medicine, Houston, Texas
S, Dupree
D,
College
of
Vecuronium
is a steroidal nondepolarizing muscle
Introduction:
relaxant closely related to pancuronium i but with a shorter duration
of action and a faster rate of recovery . This study was approved by
the Institutional Review Board.
Methods: Ten ASA physical status class I or II patients undergoing
elective postpartum tubal ligation were given cimetidine 300mg by
mouth on the morning of surgery, and metaclopramide 1Omg IV. Patients
were preoxygenated
and given fentanyl Zug/kg five minutes prior to
induction.
A peripheral nerve stimulator (Fischer and Paykel A-300)
was applied on the ulnar nerve. Patients were induced with thiopental
3mg/kg and train of four stimulation was both observed and recorded.
The patients were then give" vecuronium O.OSmg/kg and train of four
After maximal
suppression
of twitch occured the
was recorded.
Anesthesia
was maintained
with
patient's trachea was intubated.
additional fentanyl and 70% N20. If required, patients were reversed
with 2.5mg neostigmine
and 1.2mg atropine
after 25% recovery
of
twitch.
Maximum
loss of twitch occured in 3.3+ 1.7 minutes.
Results:
Intubating
Greater than 97% of tw~itch was lost in all eases,
conditions were adequate in all cases and good or excellent
in 80%.
Clinical duration (25% recovery) was 31.4t 4.7,minutes. All patients
were easily reversed with full recovery of twitch in less than 2
minutes.
Most
studies
of vecuronium
relaxat)oT4for
Discussion:
factlitation
of intubation have been done using O.lmg/kg
’ ’
ICI
Maximal
loss of twitchbccured
from 2-5.9
nonpregnant
patients.
Our findings also fell within this range.
minutes at this dose.
Clinical duration in the """pregnant patient at O.lmg/kg is reported
to be 30-35 minutes. Our results were similar with a smaller initial
dose.
Fragen and Shanks5 using O.OSmg/kg also found excellent
intubating conditions. HOWeVer, the mean degree of block was 87% and
the clinical duration was only 10 minutes.
Our findings in the post
partum patient show a greater degree of neuromuscular
blockade and
three times the clinical duration than reported in the nonpregnant
patient. This is similar to our findings using O.lmg/kg vecuronium in
linical
duration
was
2-2.5
times
the expected
;,";,c,hi"E2:3,E* The 0.5 mg/kg dose appears to be satisfactory
for
short surgical procedures in the postpartum patient.
References:
1.
Durant NN. Katz KL: Nonneuromuscular effects of vecuronium and
other competive muscle relaxants
in clinical
experiences
with
norcuron. Excerpta Media,
1983
2.
Clarke RSJ, Mirakhur RK: Intubating conditions after vecuronium;
a study with three doses and a comparison with suxamethonium and
pancuronium. Ibid, 1983
Agoston S:
3.
Clinical pharmacology of vecuronium; a preliminary
report on a multicenter study in 800 patients. Ibid, 1983
4.
Nagashina H, Kaplan R, Yun H, et al: Clinical pharmacology
of
vecuronium; a comparison with pancuronium.
1983
1983
Frngen KJ, Shanks CA: Ve<:uronium in outpatient surgery.
5.
104
8554
Title:
EFFECT OF ANESTHETIC TECHNIQUEFOR REPEAT CESAREANON
POSTOPERATIVEINFECTIOUS MORBIDITY
Author:
Chestnut
DH*
Department
of Obstetrics
and Gynecology,
Formerly:
Duke University
Medical
Center,
Durham, North Carolina.
Departments of Obstetrics
and Gynecology
and
Presently:
Anesthesia,
University
of Iowa College
of Medicine,
Iowa
City,
Iowa.
It has been stated
that general
anesthesia
is a r’sk
Introduction.
1 92
factor
for fever
and/or
infection
following
cesarean
delivery.
undergoing
primary cesarean
Previous
reports
have included
patients
cesarean
may
delivery;
however,
urgency
associated
with prim ry
‘i
anesthesia.
select
the high risk patient
for general
The hospital
records
of all
women who underwent
repeat
Methods.
cesarean
at Duke Medical
Center between November 1, 1981, and April
, with the approval
of the
30, 1984, were retrospectively
reviewed
Patients
were excluded
from the
Hospital
Medical
Records
Committee.
study if repeat
cesareau
was performed
for fetal
distress,
after
a
or after
labor or ruptured membranes of greater
than
trial
of labor,
six hours duration.
Also excluded
were patients
whose preoperative
who received
treatment
antibiotics
temperature
was 2 38.0°C,
preoperative
ly, or who underwent cesarean
hysterectomy.
Postoperative
1) Standard
morbidj.ty was assessed
utilizing
the following
criteria:
puerperal
febrile
morbidity;
2)
Modified
febrile
morbidity;
3)
Clinical
diagnosis
of infection
(Endonyometritis,
Urinary
tract
infection,
Wound infection,
Pulmonary);
4) Utilization
of therapeutic
antibiotics;
5)
Fever
index;
6)
Postoperative
hospital
stay.
Statistical
analysis
of these
data was by Student’s
t-test,
chi
square,
and Fisher’s
exact test as indicsted.
A p value of < 0.05 was
considered
evidence
of statistical
significance.
Results.
218 Patients
underwent
repeat
cesarean
during
the study
period.
Twelve
patients
were exe luded because
repeat
cesarean
was
performed
for fetal
distress
(three
patients),
after
a trial
of labor
(eight),
and prior
to hysterectomy
(one).
Among the remaining
206
patients,
epidural
or spinal
anesthesia
was successfully
administered
to 106 patients
(Group 1).
General anesthesia
was admini.stered
to 100
patients
(Group
2).
Details
of
anesthetic
techniques
will
be
preswted.
Women in Group 2 had a lower mean age, were more likely
to
be indigent,
and were more likely
to have had early
labor
and/or
spontaneous
rupture
of membranes prior
to repeat
cesarean.
Groups 1
and 2 were similar
with regard to operative
management.
There were no
statistically
significant
differences
between the two groups regarding
any of the examined indices
of postoperative
morbidity.
Discussion.
The data does not confirm
that general
nnesthesia,
as
administered
to patients
in this series,
is associated
with a greater
risk of maternal
infection
after
repeat cesarean.
References.
l.Green
SL, Sarubbi
FA:
Risk factors
associated
with post cesarean
section
febrile
morbidity.
Obstet Gynecol
49:686-690,
1977.
2.Morgan
BM, Barker
JP, Goroszeniuk
T, Aulakh
JM, Reginald
PW,
Trojanowski
A: Anaesthetic
morbidity
following
caesarean
section
under epidural
or general
anaesthesia.
Lancet i:328-330,
1984,
1~r1j
8555
_
Title:
CAUDAL THREADING OF CATHETER DURING LUMBAR
EPIDURAL GIVES BETTER ANALGESIA
IN PARTURIENTS
FOR C-SECTIONS
THAN CEPHALAD THREADING
Authors:
N. Doss, M.D.,
D. Yarlagadda,
Affiliation:
Department
of Anesthesiology,
Brooklyn, New York
11212
S.G. Humayun, M.D., J. Alfonso,
M.D., A.R. Abadir, M.D.
Brookdale
8556
M.D.,
Hospital
Approximately
twice the dose of local anesthetic
drug is
Introduction:
needed for caudal compared to lumbar epidural anesthesia
because of the
relatively
large sacral canal and the free leakage of solution out of the
large sacral foramina.
3191 of drug is required per spinal segment for
caudal conpared to 1.5ml/segment
for lumbar epidural.
1 Larger nerve fibers
require higher concentrations
of local anesthetic
for inhibition of impulse.
1 .Therefore they are more difficult and
L5, Sl, S2 are the largest fibers
S3, S4, and S5 diminish progressive1.y in
they take longer to anesthetize.
It has been stated that we need larger volume of local anesthetic
size.
solution if the catheter is threaded caudally
(I).
We decided to do this
study to evaluate if patients were going to require larger volume of local
anesthetic
if the catheter was threaded caudad and to study the degree of
analgesia
in the supine position with left uterine displacement.
Method : Twenty full term parturients
for cesaeran section were selected at
random.
The patients were divided into two groups: Group A (catheter placed
cephaladl and Group B (catheter placed caudal).
1. Informed consent was
taken from all patients.
Patients were prehydrated
with lnOOm1 of Ringers
Lactate before the administration
of lumbar epidural L3-4 using loss of
resistance
technique.
2. During the procedure maternal heart rate and blood
pressure was monitored.
3ml 1.5% lidocaine with epinephrine
1:2OO,OOO was
given via epidural needle as a test dose, after excluding
intravascular
or
subarachnoid
injection. 3. Standard Portex catheter was threaded.
The total
dose of local anesthetic was injected during a period of 10 minutes to
obtain a sensory level of T4.
The degree of analgesia was assessed by each
patient on a scale 10 to 0 [excellent
- good - adequate - inadequate].
Results - In group A catheter was placed cephalad.
In group B catheter was
placed caudal.
The degree of analgesia was better with patients in group B
than in Group A. The volume of local anesthetic
needed for T4 level group A
was not larger than the required in qroup B.
Discussion
- From the results that we have, we conclude that threarling the
catheter caudally gives better degree of analgesia.
We also found that
these patients did not require narcotics after the delivery of the baby.
(Therefore we recommend threading the catheter caudally for epidura!
anesthesia
in c-section.)
References
1. Terence M. Murphy, M.D., ChB.
Ronald Miller, M.D. Technique
_..
_
Spinal-Epidural
and Caudal
of Caudal Anesthesia
106
Anesthesia
_
EFFECT OF MATERNAL HYPOGLYCEMIA
ON NEONATAL
CL1JCO.X IN NORMAL DELIVERIES
AND C-SECTIONS
Authors:
N. Doss, M.D., S.G. Humayun, M.D., D. Yarlagadda,
J. Alfonso, M.D., A.R. Ahadir, M.D.
Affiliation:
llepartment of Anesthesiology,
Brooklyn, New York
11212
Brookdale
8557
mm-m
Title:
M.D.
Hospital
Introduction:
The purpose of this study is to compare the blood glucose
levels of parturients
at the time of delivery to the blood glucose levels
from the cord to see if there is any correlation
between maternal and
neonatal blood glucose level and neonatal blood plucose level during
delivery and soon after birth.
We will report blood sugar levels in mothers and cord at the
Method:
time of delivery of baby. 1. 10 full term parturients
were randomly
selected. 2. Blood for SM6 was drawn at the time of admission.
3. An
4. Ringers Lactate was the
informed consent was taken by all patients
standard IV fluid for all patients
: lOODm1 5. The time of last P.O. fluid
intake was noted. 6. Parturients
were divided into two groups: a.Group I c-section
under lumbar epidural, h.Group II - Vaginal deliver-y
7. Blood
samples from maternal peripheral
vein were taken for blood glucose and blood
8. Samples of blond from cord at the time of delivery, were drawn
gases.
for blood glucose & blood gases.
9. Apgar scores were noted.
Results:
Parturients
in Group I (elective c-section)
had blood guucose
levels that ranged from 64m9/dl to 89mg/dl.
Babies cord glucose range was
62mg/dl to 70mg/dl.
Parturients
in Group II (vaginal normal deliveries)
maternal blood glucose ranged from 52ng/dl to 56mq/dl and babies cord
glucose ranged 35mgldl to 44mg/dl.
Apgar scores were 9/9-g/10 in both
groups.
Patients had fluid intake 8-10 hours before time of delivery in
both groups.
Discussion:
The normal blood glucose level in adult is 75-110mgs/dl.
The
blood glucose levels, in Group I were on the lower limit of normal, whereas
in Group II maternal blood glucose levels were consistantly
below normal.
This we artibute to the high energy consumption
during normal labor.
Fetal
cord blood glucose were within the normal range ( 62mg/dl - 70mg/r'l in Group
I whereas in Group II they were on the lower limit of normal (35mg/dl 44mg/dl). From these results we conclude that "Glucose administration
should
not be avoided altogether,
however, since ideal neonatal condition
ensues
when the maternal blood sugar concentration
is kept within
the normal range
of a0 to 120ml".l.
References:
1. Gerard Bassell,M.D.,Anesthesia
for complicated
Obstetrics
134 ASA Refresher Course
1.07
_
_
Title:
EFFECT OF EPINEPHRINE
ADDED TO THE EPIDURAL LOCAL ANESTHETIC
FOR CAESAREAN SECTION ON THE INCIDENCE AND SEVERITY OF POST
EPIDURAL MORPHINE PRURITIS
Authors:
Douglas,
Affiliation:
Department
of Anaesthesiology,
The University
Columbia,
Vancouver, British Columbia
MJ*,
Kim, JHK,
McMorland,
8558
GH
of British
Epidural
morphine
for post Caesarean
Section
analgesia
Introduction.
One of
allows early patient mobilization
and so has become
popular.*
the more annoying
side effects is pruritis,
which is usually mild, self
The addition
of epinephrine
1:200,000
to
limited
and dose dependent.
epidural morphine has been shown to increase the severity and incidence of
side effects.2
This study was undertaken
to see if epinephrine
added
to the local
anesthetic
for Caesarean
Section
had an effect
on the
pruritis as~sociated with epidural morphine.
73 patients, ASP I for elective Caesarean Section were entered
Methods.
A standard
epidural
into the study and informed
consent was ohtained.
technique was used and 1 of 3 local anesthetic
mixtures was injected into
the epidural space to produce surgical anesthesia to T4.
A 3 cc test dose
0.5% hupivacaine
with
was always used.
The 3 anesthetics
were:
1.
epinephrine
1:400,000
used for test dose and anesthesia
(n=29)
2.
0.5%
hupivacaine
plain used for test dose and anesthesia
(n=23)
3.
0.5%
hupivacaine
with 15 ugms epinephrine
used for test dose followed by 0.5%
Twenty
minutes
after
the
hupivacaine
plain
for
anesthesia
(n=Zl).
umbilical
cord was cut the patient was given 5 mgms preservative
free
morphine in 10 ml saline through the epidural catheter.
Each patient was given a linear analogue
"itch scale" to complete
when
itching
"became
bothersome"
or 6 hours
post
epidural
mnrphine.
The
patients
were also visited and the charts reviewed
to determine
if any
medication
was given for pruritis.
Neither the patients
nor the nursing
staff were aware of the local anesthetic
solution used.
Results.
Results indicate that the severity of pruritis as demonstrated
by completion of the "itch scale" and medication
requests is statistically
greater in the groups where epinephrine
was added to the local anesthetic.
Discussion.
In 1983 Bromage demonstrated
that
segmental
hypalyesia
occurred after injection of epinephrine
in saline into the epidural space.
This lasted
about 6 hours.
No adverse
effects
such as pruritis
were
demonstrated
at that time.
It has heen felt that enhanced
effects
of
epidural
morphine,
when epinephrine
is added,
were due mainly
to the
action of epinephrine
outside the cord and to reduced vascular
clearance
of epidural morphine
from the epidural
space.
This study has shown that
the addition
of epinephrine
to the
local
anesthetic,
which
is later
followed by epidural morphine
still exerts this enhanced effect, at least
on the pruritis.
More information
is required about the pharmacokinetics
of epinephrine
in the epidural space.
References.
l.Carmichael
FJ,
Rolbin SH,
Hew EM:
Epidural
Morphine
for Analgesia
After Caesarean
Section.
Can Anaesth
Sot J Vol 29 No4 July
19B2.
2.Rromaye
PR,
Camporesi
EM,
Durant
PA,
Nielsen
CH.
Influence
of
Epinephrine
as an Adjuvant
to Epidural
Morphine.
Anesthesiology
58:
257-262, 1983
_
Title:
THE USE OF CONTINUOUS I" NUBAIN INFUSION IN AN ATTEMPT
TO-ABORT THE SIDE EFFECTS OF MORPHINE EPIDURALS WITHOUT AFFECTING THEIR ANALGESIA
Authors:
Greenhouse BB, Lang C*
Affiliation: Department of Anesthesiology, Albany Medical Center
Hospital, Albany, New York
Introduction. Studies show that the duration of epidural morphine
analgesia ranges from 4-51 hours with an average of 18 hours. Side
effects associated with epidural morphine include: respiratory
depression, pruritus, nausea, vomiting and urinary retention.
Nalbuphine (Ntiain) is an agonist/antagonist analgesic. An intramuscular dose of 3 mg of nalbuphine causes analgesia equivalent to
that of 1 mg morphine. Nalbuphine depresses respiration as much as
do equianalgesic doses of morphine; however, nalbuphine has a ceiling
effect, such that doses greater than 30 mg produce no further respiratory depression. Its onset of action occurs within 2-3 minutes after
IV administration. The plasma half-life is 5 hours and the duration
of analgesia is' 3-6 hours. Side effects include sedation, sweating,
vomiting, dizziness, dry mouth, headache and dysphoria.
nausea,
Intravenous naloxone is an antidote for overdosage.
Methods. We will report the effects that a continuous nalbuphine
infusion has on the side effects and analgesia after morphine epidurals
in post-Cesarian section patients. We hope to have 30 patients who
will undergo Cesarian sections under continuous lumbar epidural anesthesia with bupivacaine, 2 - chloroprocaine or lidocaine. Five mg of
morphine will be injected through the epidural catheter in the recovery
room when the patient requests analgesia and the catheter will be
removed. TWO hours later either a continuous nalbuphine intravenous
infusion (5 mg/hr) or a saline infusion (control group) will be started
md will run for 12 hours. This will be double-blind. All patients
,iillbe continuously monitored for 20 hours and will be checked for
guise, respiratory rate, blood pressure, side effects, sedation, pain
relief and pain intensity.
Results. We have no results yet, but hope to have half the study
completed by the time of the presentation.
Discussion. At the conclusion of the study we hope to have sufficient data to make recommendations regarding the routine use of a
nalbuphine drip in conjunction with epidural morphine analgesia for
postoperative pain.
References.
l.Rosen MA, Hughes SC, Shnider SM, Abboud TK, Norton M, Dailey P,
Curtis JD: Epidural morphine for the relief of postoperative pain
after cesarian delivery. Anesth Analg 62:666-672, 1983.
2.Bromage PR, Camporesi EM, Durant PAC. Nielsen CA: Nonrcspiratory
side effects of epidural morphine. Anesth Analg 61:490-495, 1982.
3.Knill RL, Clement JL, Thompson WR: Epidural morphine causes delayed
and prolonged ventilatory depression. Can Anaesth Sot J 28:537-543,
1981.
1.09
8559
Title:
HUMAN PLACENTAL LACTATE PRODUCTION IN VITRO
Authors:
Greenland, VC*, Wasserman, JF, Young, BK, Dancis, J,
Ramnathan,
S.
8560
Affiliation: Departments of Obstetrics & Gynecology, Pediatrics, and
Anesthesia, New York University Medical Center, New York, NY
Lactate production from 20 normal term human placentas was investigated. Eighty fragments between 100 and 300 mg from five placentas
were incubated with glucose with 95% oxygen and lactate measured.
Ninety-eight fragments of another five placentas were studied using
100% nitrogen.
Under hyperoxic conditions the mean lactate was
5.547fO.507 micro mol/g/hr.
Under hypoxic conditions it was 7.573t1.427
micro mol/g/hr.
The t-test was significant (p ( .02). Another ten
placenta~s were studied using the same placenta under different conditions of oxygenation.
Lactate production was also measured under
anoxic conditions in a closed container filled with nitrogen. With
hyperoxia the mean lactate was 7.773t1.693 micro mol/g/hr and with
The difference was not statistichypoxia, 7.147t2.267 micro mollgjhr.
ally significant for the ten placentas. With anoxia, mean lactate was
5.667kO.893 micro mol/g/hr, not significantly from hypoxia. The pyruvate
produced under these different conditions was not significantly different.
under
Under hyperoxic conditions, it was 0.4420.31 micro mol/g/hr;
hypoxic conditions, it was 0.34tO.15 micro mol/g/hr, and under anoxia
it was 0.55tO.55 micro mol/g/hr.
In vitro, it appears that the placenta
metabolizes glucose at approximately the same rate under conditions of
This leads to the speculation that in viva the
hypoxia and hyperoxia.
placenta could be a lactate producer with anaerobic metabolism similar
to malignancies.
110
_,
Title:
PERIP'ARTUM
THE EFFECT
Authors:
Jones
Joyce
Affiliation:
Departments
Gynecology,
Texas.
M,
TH
COLLOID
OSMOTIC
PRESSURE:
CHANGES
IN
OF VARIOUS
PRE-OPERATIVE
FLUID
REGIMENS
*
Cotton
D,
Longmire
of Anesthesiology,
Baylor
College
of
S,
Dorman
K,
and Obstetrics
and
Houston,
Medicine,
A prospective
study
is being
performed
to
Introduction.
evaluate
the serial
plasma
colloid
osmotic
pressure
(COP) changes
in cesarean
section
patients
when hydrated
with one of three preoperative
fluid
regimens.
Intraoperative
and postoperative
fluid
administration
(PLA)
was
similar
in all
three
groups.
COP
measurements
were obtained
prehydration
(pre-H),
posthydration
(post-H),
at the completion
of surgery
(post-S)
and at 4, 8, 16,
An umbilical
venous
(UV)
postoperatively.
24, 36 and 48 hours
COP was obtained.
Methods.
Institutional
Review
Board approval
of the study was
obtained
and written
informed
consent
secured
from each
patient.
Twenty-eight
cesarean
section
patients
each received
one of three
preoperative
hydration
regimens:
1000~~
Plasma-Lyte
A (PLA) (9),
2000~~
PLA (10) or 1000~~
5% Albumin
(9).
. ,
Preliminary.Results.
5% Albumin
2000~~
PLA
1000~~
PLA
Pre-H
22.1 f- 1.9+
22.9 + xx+
T5.4 f 2.0+
Post-H
19.0 + 2.6"+
18.9 + 2.3+
23.9 + 2.9+
Post-S
17.9 + 2.3*+
18.3 7 2.8*+
22.5 + 2.6+
4 Hr
17.9 + 2.0*+
20.6 + 2.7**+
17.2 ? 2.3*+
17.3 z 1.9*+
8 Hr
17.5 ; 1.8*+
20.5 f 3.3**+
16 Hr
16.3 ; l.O*+
18.3 ; 1.7*+
20.0 _+ 3.0**+
24 Hr
18.6 ; 2.0*+
19.0 ; 2.3*+
21.5 + 2.1**+
18.4 ; 1.8*+
36 Hr
19.1 _+ 1.5*+
20.6 _+ 2.7**+
48 Hr
21.4 e 1.8**+
19.8 _+ 2.2*+
23.1 + 3.2+
uv
18.7 f 2.2+
19.1 _+ 2.8+
18.1 _+ 2.0+
* p < 0.01 compared
to Pre-H;
** p < 0.05 compared
to Pre-H;
+ NS between
groups
at this time interval,
p > 0.05
The largest
decrease
in COP (26% compared
to Pre-H)
occurred
at
16 Hr in the
2000~~
PLA group.
A statistically
significant
decrease
in COP was still
present
at 48 Hr in both
PLA grups.
The
5% Albumin
group
had
the
least
fall
in COP
from
control
(14.6%).
Peak falls
occurred
in the 4-16
hour time frame
in all
treatment
groups.
Comparison
of COP
values
within
the
time
by
unpaired
t-test,
was not significant
at the p = 0.05
groups,
level.
No difference
in UV COP was detected
between
the groups.
Discussion.
Peak
falls
in COP
occurred
4-16
hours
post
--_--surgery.
By inspection,
the
5% albumin
produced
the
least
changes
in COP during
the test period.
However
the wide range of
COP values
in this
group
rendered
the intergroup
differences
statistically
insignificant.
Thus,
based
on this
preliminary
data,
the use of 5% albumin
for pre-operative
volume
loading
does
not
appear
to provide
any
advantages
based
on COP
changes.
Further
patients
are being
completed
in each group.
111
8561
8562
Title:
AN EVALUATION
OF ALFENTANIL AS AN INDUCTION AGENT AND FOR
CARDIOVASCULAR STABILITY DURING ENDOTRACHEAL INTUBATION
Author:
Joyce TH,* Jones M, Camp C, Longmire S, Dupree D, Adenwala
Rodriguez V, Skjonsby B
Affiliation:
Department
of Anesthesiology,
Houston, Texas
J,
Baylor College of Medicine,
_
Introduction:
Alfentanil
Is reported to be a rapid onset, short
duration, potent synthetic narcotic capable of producing a satisfactory
induction of general anesthesia.
Review
Institutional
Methods:~
After written informed consent and
Board approval, a dose ranging study was undertaken in 20 ASA class I or II
Cimetidine
300mg orally and
patients for postpartum
tubal ligation.
metachlorpropamide 1Omg IV were the pre-anesthetic drug. Pancuronium 1 or
1.5mg was administered during pre-oxygenation prior to the induction dose
of alfentanil.
Following Loss of vocal response , succinylcholine 1OOmg was
Maintenance anesthesia
given IV to facilitate
adotracheal
intubation.
was 70:30 nitrous oxide: Oxygen and a 0.2% succinylcholine
drip and
Halothane O-0.5%
Results:
203
175
150
125
1<6osec
2<6Osec
4<6Osec
2<6osec
1
2
6
3
+3
+20
+7
+3
6
-10
i4
-10
L
2
1
0
1
2
1
0
1
0
0
0
0
0
0
0
1
2
4
2
Discussion: All cases demonstrated remarkable cardiovascular stability
at the time of endotracheal intubation in spite of several laryngoscopies
in 5 patients
(Fire Dept. paramedic
training).
Chest wall
and body
rigidity were seen at dose 175ug/kg and above.
Because of lack of recall
of induction approval
of the IRB was sought to look at two additional
groups 75ug/kg and LOOug/kg. The profound cardiovascular stability seen to
date may make this drug an ideal induction agent in the patient with
Pregnancy Induced Hypertension. AL1 twenty cases will be presented.
112
8563
TITLE:
FASTING
AUTHORS :
eassa
AFFILIATION:
Temple
SERUM GLI_lCiXE LEVELS
*
c,
Chatwani
Llniversi
A.
t:,
Kenepp
Hospital,
IN THE HEALTHY PARTURIENT
NB
Philadelphia,
Pennsylvania
Routine
preoperative
preparation
for
elective
Intro,duction.
C-section
includes
an overnight
fast,
which
may frequently
be as long
ac- 12 hours.
result.ing
in depletion
of glycogen
reserves
in the liver
and increased
gluconesgenesis.
Low maternal
glucose
levels
are
worrisome:
if maternal
hypoxia
occurs
glucose
requirments
will
be
increased
and maternal
hypoglycemia
may lead
to neonatal
hypoglycemia.
This
prospective
was designed
to determine
whether
fasting
parturients
hecome
hypoglycemic
and whether
maternal
serum
glucose,
levels
Duration
of fast
does
not
correlate
I*lith the duration
of
the fast.
correlate
with
s.erum glucose
levels
at delivery
in laboring
patients,
however
this
maybe
a reflection
of catecholamine
levels
rather
than
Elective
C-section
patients
may have
potential
glucose
supplies.
hypoglycemia
at parturition
despite
its
absence
in vaginal
deliveries.
by the commi ttrr
for
Methods.
The protocol
was approved
Human Studies
and Informed
Consent
waz. obtained
from
term kSA 1 or 11
paturients
on the evening
prior
to a scheduled
elective
C-section
or
induction
of labor.
The patients.
were
told
to remain
NPO after
midnight
and to remember
.the
time
of their
last
oral
intake.
In the
morning
a serum
glucose
level
was. obtained
prior
to starting
the
intravenous
and the duration
of fasting
was ascertained.
Maternal
height,
weight,
age,
parity
and infant
six,
weight,
apgar
scores
and
gestional
age were
also
recorded.
Results
and Discussion.
Maternal
serum
glucose
levels
below
6Orfv+~100ml were
considered
indicative
of possible
depletibn
of
reserves.
The study
is ongoing
and the proportion
of patients
meeting
our definition
of hypoglycemia
will
be available
at the
time
of
presentation.
In addition
the relation
of durat,ion
of fast
to
maternal
blood
sugar
will
be determined
statistically.
Eased
on this
recommendat
i on5 regarding
data,
correction
of hypoglycemia
will
be
di scuss.ed.
113
8564
Title:
QUANTITATIVE PLACENTAL TRANSFER DURING SIMULATED EPIDURAL
ABSORPTION
Authors:
Kennedy
Vicinie
Affiliation:
Departments
University
and College
RL,”
A.
Tyler
IL,
Edelmann
CA, Miller
of Anesthesiology,
Magee-Wornens
and West Virginia
of Pittsburgh,
of Pharmacy,
Medical
College
of
RP,
Jopling
MW,
Hospital
and
University,
South Carolina
Maternal
administration
of
a drug
to evaluate
Introduction.
placental
transfer
has been
accomplished
either
by bolus
or constant
Neither
reproduce
the blood
concentrations
rate
intravenous
injection.
in the time-course
that occurs
following
absorption
from
the epidural
This
infusion
limitation
has
prevented
a comprehensive
space.
evaluation
of placental
transfer
and led to conflicting
interpretations.
Utilizing
a pregnant
ewe
preparation,
this
study
evaluates
in a
continual
and quantitative
manner the fetal
uptake
of bupivacaine
during
a maternal
infusion
that
simulates
epidural
absorption
(first-order
A computer
controlled
pump controls
the
infusion
according
kinetics).
to the formula
describing
this
absorption.l
120 days
gestation,
are
prepared
for
Date
bred
ewes,
Methods.
chronic
studies
with
the
following
placements;
catheters
in a maternal
fetal
distal
aorta
(FA),
common
artery
(MA),
maternal
vein
(MV),
An electromagnetic
flow
umbilical
vein
(UV),
and
fetal
bladder.
transducer
is
positioned
around
the
common
umbilical
artery.
is added to 1 liter
normal
saline
and
Bupivacaine,
3 (2.7
base)
mgakg-1,
infused
into
the MV by a Critikon
infusion
pump controlled
by an Apple
The infusion
rate
determined
from
the
formula
is
II Plus
computer.
is sampled
simultaneously
from
the
updated
every
6 sec.
Blood,
0.5 ml,
MA, UV, and FA.
All
samples
are
placed
in borate
buffer
(pH 9.5)
and
At hourly
intervals
fetal
urine
is collected.
frozen
until
analyzed.
Maternal
and fetal
blood
gases
and pH are determined.
Bupivacaine
and
2,6_pipecoloxylidide
(PPX)
are
measured
in all
samples
by high
performance
liquid
chromatography
(HPLC).
Fetal
uptake
is calculated
from the product
of
the
UV-FA concentration
difference
and umbilical
blood
flow
(Qu).
Fetal
acccumulation
is calculated
by time integrating
fetal
uptake.
Results.
Two preparations
have
been
successfully
completed.
The
results
of the blood
bupivacaine
await
determination.
Results
of all
completed
animal
preparations
will
be reported.
Discussion.
The results
will
demonstrate
the
relationship
between
umbilical
cord
concentrations
and fetal
uptake
as they relate
to the
time of administration.
It is anticipated
that
the discrepancy
between
hiah cord
levels
and low fetal
untake will
be resolved.
Reference
1.
Tucker
GT, Mather
LE:
Clinical
pharm~acokinetics
of
local
anesthetics.
Clin
Pharmacokinetics.
4:241-278,
1979.
114
8565
Title:
THE USE OF GALLAMINE TRIETHIODIDE IN CESAREAN SECTIONS
Authors:
Khalil SN.* Abouleish EK,Pallo" KB,Zavisca FG and Shao MJ.
Affiliation: Department of Anesthesiology, University of Texas,
Houston. Texas
Introduction. There is a controversy regarding the safety of
gallamine (G) in obstetrics. Clinically, ft was safe for both mother a"d
newborn. However, Schwartz in 1958, found a high transfer of iodide
molecule across the placenta and assumed that this was an indication of
a high placental transfer of (G). Our study was performed to determine
its safety using modern clinical and laboratory techniques.
Methods. The material consisted of 13 healthy patients scheduled for
elective cesarea" section. Approval of the Human Research Committee and
informed consents were obtained. Anesthesia was induced using Thiopental
4 mg/kg followed by succinylcholine 1 mg/kg for intubation. When
recovery of the muscle twitch occurred (C) 1.5 mg/kg was injected.
Anesthesia was maintained by Nz0:02(4:2). At the time of delivery the
newborn was evaluated by Apgar scores, time to sustained breathing, and
muscle status using a modified NAGS(I) including only tests for passive
and active tone, and primary reflexes. Maternal and umbilical blood
gases and acid base status were determined. The plasma levels of (G)
itself in umblical cord and maternal venous blood at delivery were
determined using high power liquid chromatography.
Results. There was no evidence of neonatal paresis or paralysis
(Table 1). The maternal (C) plasma level was 7.58tO.64 pg/ml. The
umblical venous and arterial plasma concentrations were 3.1320.47 and
2.4920.47 pg/ml respectively. The M.V.:U.V.:U.A. ratios were 1.00 :
0.41 : 0.32. Statistically the maternal level was significantly higher
than the fetal levels (p<O.OS) while there was no statistical difference
between U.V. and U.A. levels. There was no correlation betwee" the
fetal plasma (G) level and the condition of the neonate.
DiSCUSSfOtl. The good condition of the neonate despite the presence
of relatively high levels of (C) might have been due to being still
below the LD 50 of (G).(2) However, the high fetal to maternal ratio of
(G) is disturbing. With the introduction of new muscle relaxants having
much lower transmission to the fetus, the authors cannot recommend (C)
for obstertics.
Apgar Score
MNACS*
Blood Gases**
Total Score Muscle Tone
lm 5m
lm 5m
M.A.
U.V.
1J.A.
>20
12
PH 7.32tO.02
7.2420.03 7.2OtO.03
<? 1 12
2
8 13
2 20
1
PO, 132t10.7
30t3.2
18.6t4.3
<
013
1
5
0
PCO, 36.621.84 51.6t2.92 60.5a3.5
0
0
0
* Maximum score = 24
** Mean (?SEM)
References.
l.Amiel-Tison C, Bannier G, Shnider SM, Levinson G, Hughes SC, Stafani
SJ: A new neurologic and adaptive capacity scoring system for
evaluating obstetric medications in full-term newborns. Anesthesiology
56: 340-350. 1981.
Z.Ramzan IM? Shanks CA, Triggs EJ: Relationship between gallamine plasma
concentration and neuromuscular paralysis in surgical patients. J Clin
Pharmacol 23, 245-251,1983.
115
8566
Title: CONTINUOUS EPIDURAL INFUSION USING 0.0625%
BUPIVACAINE
Authors: Knapp RN*, Heins S, Denson D
Affiliation:
Departments of Anesthesiology, Tufts University,
University of Cincinnati, Ohio
Boston. Massachusetts, and
Introduciian: During labor, epidural anesthesia may be provided using intermittent boluses or
a continuous infusion of local anesthetic.
With the former technique, lesser anesthetic
concentrations are assmiated with lesser degrees of motor block. but also shorter durations of
ac?ion. A continuous infusion of 0.06258
bupivacaine, which does not require frequent
reinforcement, might be expected to provide minimal degrees of motor block. The small amount
of anesthetic used might also limit the plasma bupicacaine levels achteved.
m
Thm study was approved by the Institutional Review Board. Twenty term parturients
who requested lumbar epidural analgesia for labor were selected at random. Informed Consent
was obtained from each. Each parturient was given an initial bolus of IO ml bupivacaine 0.5X.
Bupivacaine 0.0625X was then infused at 20 ml/hr until delivery. Painful sensationsduring
the infusion were treated with one or two 3 ml boluses of bupivacaine 0,5X. Sensations of
pressure resulted in no treatment, Motor block was assessed every thirty minutes according to a
method described by Bromage ( I ) Forceps c&liveries were preceeded by a IO ml bolus of
bupivecaine 0.5X ten minutes prior to leaving the labor room. Venous blood specimens taken
every fifteen minutes from twelve parturients throughout the infusion, as well as maternal and
umbilical vein specimens taken at delivery, were analyzed for bupivecaine. Results are
expressed as mean + SD~ Comparison of delivery related concentrations were made by means of
a I- test for independent means,
Besulls. Each parturient remained at essentially one level of motor blockade throughout the
infusion. Fourteen remained between OX and 33X, five remained at 33X, and one remained at
67X. Bupivacaine levels peaked at 0.68 ~0.14 ug/ml at 0.58 + 0.25 hr after the initial
injection. Following that, the levels continuously declined, regardless of the length of infusion
or whether 3 ml supplemental boluses were employed In those parturients receiving a 10 ml
supplement prior to delivery, delivery concentration was 0.76 + 0.13 ug/ml.
This was
significantly higher than the 0.49 + 0.12 ug/ml found in those not receiving this bolus.
(P(O.0 I) All parturients expressed satisfaction with the course of anesthesia.
Discussion: In this series of parturients,
bupivacaine 0.0625X wasclinically
well accepted
Motor blockade almost never exceeded 33X. This limitation of clinical effect was mirrored by
the limited plasma bupivacaine levels seen, which remained below 1 fig/ml for all infusions.
This is well below the 4 ug/ml associated with convulsions in situations involving bolus
injections of anesthetic. (2)
During continuous intravenous infusion, convulsions have
recurred at 1.1 ug/ml. (3)
Whether a continuous epidural infusion is comparable to a
WntinuOuS
intravenous infusion is not clears Nonetheless, these results demonstrate that a
margin of safety exists regardless of which limit might be more appropriate.
F&f1. Bromage PR: Epidural analgesia. Philadelphia: W.B, Saunders Company,
1978: 144. 2. Moore DC, Balfour RI, Fitzgibbons D: Convulsive arterial plasma levels of
bupivacaine and the response to diazepam therapy. Anesthesiology 50:454-456,
1979~
3~ Hasselstrom LJ, Mqensen T: Toxic reaction of bupivecaine at low plasma concentration.
Anesthesiology 6 I :99- 100. 1984.
116
-
Title:
GENERAL ANESTHESIA
FOR CAESAREAN
SEVERELY HYPERTENSIVE
MOTHERS.
SECTION
Authors:
Lawes EG,* Connell H, Duncan
Lavies N, Downing JW.
Affiliation:
Department
of Anesthesiology,
Faculty of
of Natal, Durban,S.A.
Medicine, University
PW, Bland
IN
B,
Introduction.
Intubation
of
severely
hypertensive
mothers
is associated
with
dangerous
elevations
in
increased
resulting
in
an
maternal
blood
pressure
accidents
incidence of cerebral oedema, cerebra-vascular
accepted way
and pulmonary oedema. There is no universaly
to avert this hypertensive
response.
will report changes in maternal arterial
Methods.
We
pressure during intubation using a neurolept
technique.
The study was undertaken with Ethical committee approval,
and
appropriate
informed
consent.
13 multiperous
sustained
diastolic
patients,
> 25 years of
with
age,
pressures of >120 mmHg were studied. Permenant records of
arterial
pressure were obtained from indwelling
arterial
catheters.
Preoperative
preparation
included
the
During
anti-hypertensive
therapy.
administration
of
preoxyqenation
fentanyl 2_5ug/kg was given in a divided
dose
in addition
to
droperidol
lignocaine
and
5mg
If a reduction of maternal blood pressure
to
a
lmy/kg.
level
of
<170
mmHg systolic, or <130mmHq mean, had not
occured following this therapy bolus doses of trimetephan
they
2.5 mg were given. Once patients met these criteria
induced
followed
by
were
with
etomidate
0.2mg/kg,
suxamethonium
100
mqlkq
intubation.Materno-fetal
for
perfusion gradients were
calculated
from
maternal
and
umbilical
vessel blood samples obtained at delivery. TSR
intervals and Apgar scores were
used
for
assesment
of
neonates.
Results. Highly statisticaly
significant
reductions
in
blood
pressure
occured
following the administration
of
the preinduction
drug
regime
compared
to pretreatment
values.
Intubation was not associated with a significant
elevation of mean arterial pressure
(MAP) when
compared
to
immediate
post
induction
MAPS,
nor
was
there
a
significant
difference
between
induction
and
post
pre
induction
MAP.
However,
a statisticaly
significant
elevation in MAP was evident between
the
induction
pre
post intubation pressures.
I and the peak
Discussion.
A close correlation
exists between changes
in MAP
during
laryngoscopy
and
circulating
levels of
noradrenaline(
Low dose fentanyl
(5ug/kq) given
prior
to
induction has been demonstrated
to effectively
reduce
circulating
noradrenaline
levels and elevations
in blood
pressure
during
accelerated
induction(a).Animal
studies
have demonstrated
the
safety
of
fentanyl
in pregnant
ewes.A
technique is described that significantly
reduces
the
pressor
response
to
intubation
in
severely
hypertensive
mothers,
without
apparent
harm
to
the
neonate.
References.
l-Derbyshire
DR. Smith G.
Sympathoadrenal
responses
to
56:725-730
anaesthesia
and surqerv. Br.J.Anaesth.1984
2.Cork
RC,
Weiss -JL;
Hameroff
SR, Bently J. Fentanyl
preloading
for rapid sequence induction.
Anesth.
Analg.
117
1984 63:60-64.
8567
TITLE:
USE OF THE ENDOCARDIAL VIABILITY RATIO AS A PIEASURE OF
MTOCARDIAL ISCHEMIA IN SEVBRE PREGNANCY-INDUCED HYF%RlXNSION
S. Longmire, MD*, J. Tessem, MD, M. Jones, MD, K. Dorman, RN
B. Skjonsby, RN, D. Cotton, MD, T. Joyce, III, MD
AFFILIATION: Departments of Anesthesiology and Obstetrics and Gynecology
Baylor College of Medicine, Houston, Texas
AUTHORS:
The Endocardial Viability Ratio (EVR) has been used as an
Introduction:
early indicator of subendocardial ischemia in cardiac surgery.
Data for calculation of the EVR was collected retrospectively
Methods:
from hemodynamic recordings from patients enrolled in other studies with
We evaluated recordings from 10 patients with severe PIH:
IRB approval.
4 before instituion of any therapy (Group I), and 6 during various phases
of therapy (Group II). All patients from whom data was obtained were
EVR*s were calculated using the
enrolled in studies with IRB approval.
equation:
E”R
-
(DAP- PCWP)
* Td ,
_---__-
where
MAP * Ts
DAP = diastolic
arterial pressure; PCWP = pulmonary capillary
wedge
pressure; Td = diastolic time; MAP = mean arterial pressure; and Ts =
systolic time. The Rate-Pressure Product (RPP) was also calculated Eor
comoarison.
GEST
RPP
EVR
Results:
AGE
G
P
GROUP I (No Mg-)
26
1
0
31.3
17,563 + 2,630
0.91 + 0.05
GROUP II (Mg++)
18
1
0
37.9
17,032 + 2,256
0.63 + 0.21
with vol exp alone
17,199 + 1,899
0.49 + 0.11
0.77 + 0.14
NTG alone
15,718 + 2,216
NTG + vol expansion
16,906 + 2,646
0.61 + 0.12
0.51 t 0.2:
Pre-induction on NTG
21,227 + 2,759
Intubation on NTG
29,385 t 6,011
0.44 t 0.15
Delivery (no NTG)
20,121 + 2,908
0.39 t 0.08
30 min post-op
17,387 + 2,392
0.64 t 0.19
Discussion:
Hoffman 6 Buckberg",
using radioactive
microspheres,
demonstrated
that the ratio of subendocardial
to subepicardiaL
blood
flows remains constant about one until the EVR falls to 0.7, when both
ratios fall together.
This relationship
of myocardial
blood flow
distribution and E$ was constant regardless of how the change in EVR was
achieved.
Philips *, studied the use of the EVR in cardiac surgery and
found a significant decrease in survival among patients with EVR*s < 0.7.
The EVR's in GROUP 11 (except during infusion of NTG in non-volumeexpanded pts.) were all less than 0.70. The precipitous
drop in EVR
which occurred at delivery
is disturbing,
especially
since all our
patients were delivered by caesarean section under general anesthesia.
Data from healthy gravidas
are not yet available,
so the clinical
significance of our current data remains speculative. More widespread use
of this easily calculated
ratio may help prevent episodes of ischemic
myocardial dysfunction in severe pre-eclamptics.
References:
1. Hoffman JIE, Buckberg GD: Regional myocardial
ischemia - causes.
prediction, and prevention. V&c Surg d:115-130, 1974.
2. Philips PA, et al.: A clinical method for detecting subendocardial
ischemia after cardiopulmonary bypass. J Thor CV Surg 69:30-39.1975.
118
8568
Title:
THE EFFECTIVENESS OF ULTRA LOW DOSE DROPERIDOL IN
CONTROLLING NAUSEA AND VOMITING DURING EPIDURAL
ANESTHESIA FOR CESAREAN SECTION
Authors:
Nandell
CL*
8569
end Dews" DM
Affiliation: Section of Obstetric and Gynecologic Anestheais, Wake
Forest University, Winston-Salem, North Carolina
M&?d!?ctig!!. Neusea and waiting occur cornonly during
intraabdominal surgery in co"acious patients. This corplicetee
surgical care, increases the risk of aspiration, end distresses the
patient. Droperidol is s safe antiemetic whose effects last into the
postoperative period (1). However, large doses ray produce sedation
and delay recovery from sneatheaia (2). Ultra low dose droperidol
effectively controla "sues end vomiting in women undergoing
outpetisnt gynecologic surgery without producing sedation (3). This
study evaluates the antienetic effectiveness of ultrs low dose
droperidol in tern psrturienta having ceaares" sections under
epidural anesthesia.
!!!&h!&. The Clinical Research Practices Committee approved the
protocol snd all subjects gsve signed informed consent. Heslthy term
parturients (ASA I and II) with singleton pregnsncea scheduled for
ceaares" section under epidural anesthesia participated in the study.
All parturienta received 3Occ of 0.3N sodium citrate by mouth.
Following randomization to the placebo or treatrent group, sn
anesthesiologist, blinded to the study, esteblished anesthesia in a
routine manner using 3% 2-chloroprocaine and/or 0.5% bupivacaine. We
recorded maternal blood pressure and pulse rate at five minute
intervals and aggressively treated a decrease in systolic blood
pressure of more than 25X or less than 100mnHg. In addition we noted
the occurence of nausea or vomiting. Iarediately following delivery
and cord clamping, the parturienta received either 0.519 of
droperidol or placebo intravenously in s double blinded fashion.
Subsequent nausea or vomiting was treated first with an equal amount
of test drug then with 0.5ng of droperidol or any other suitable
antiemetic. We adminiated intravenous fentanyl during surgery end
morphine sulfate postoperatively as needed. If other anesthetic
adluvants were required, the sub]ecta were eliminated from the study.
R%%!!lt_E.A total to 250 parturients will be studied. We
anticipate that at the time of this presentation 70 parturiente will
have bee" studied. The preliminary results will be discussed at that
tine.
R~~~~.K!!Z$~.
l.Santos A. Datta S: Prophylactic Use of Droperidol for Control of
Nausea and Vomiting during Spinal Anesthesia for Ceaarean Section.
Anesth Analg 63:85-87, 1984.
Z.&hen SE, Woods WA, Wyner J: Antiemetic Efficacy of Droperidol and
Metocloprsmide. Anesthesiology 60:67-69. 1984.
3.Shelley ES, Brown HA: Antiemetic Effect of Ultra LOW Dose
Droparidol. Abstracts and Scientific Papers, ASA Annusl Meeting
633-634, 1978.
_
.-
-
-.
Title:
PERIPARTUM CARDIOMYOPATHY
PRESENTING AT CESAREAN DELIVERY
Authors:
Malinow AM* , Butterworth J, Rein M, Safon L, Hartwell B,
Datta S, Lind L, Johnson M, Naulty JS, Ostheimer GW
Affiliation:
Departments of Anesthesia & Obstetrics and Gynecology,
Brigham and Women's Hospital and Harvard Medical School,
Boston, Massachusetts
02115
8570
Peripartum cardiomyopathy is defined as the presentation
Introduction.
of primary myocardial disease during the last month of pregnancy or in the
first five months postpartum in a patient without previous cardiac disease
and without specific etiology. 1 Its reported incidence is l/3000 to l/4000
pregnancies and represents < 1% of cardiovascular disease in the parturient.'
This presentation discusses two patients with peripartum
Discussion.
cardiomyopathy whose cardiac disease was unmasked while under anesthesia
given for cesarean delivery.
The first patient was a 17 year old Cambodian primagravida at 30 weeks
estimated gestational age with a history of poor nutrition and no antenatal
care who was delivered abdominally for fetal distress under general anesthesia.
The second patient was a 25 year old Caucausian multigravida who was
scheduled for elective repeat cesarean delivery. Admitted in spontaneous
labor, she was delivered abdominally under spinal anesthesia.
Each patient acutely decompensated while anesthetized, presenting with
dramatic signs of left ventricular heart failure. Both needed prolonged
ventilatory and cardiovascular support. Each patient recovered from the
acute episode and was discharged from the hospital in satisfactory condition
with a cardiac diagnosis of peripartum cardiomyopathy .
-
Conclusion.
There are 454 well-documented cases of peripartum cardiomyopathy in the world literature.2
We believe these cases to be unique in
the timing of their cardiac decompensation while under anesthesia and their
resolution after aggressive cardiorespiratory therapy.
1.
2.
References.
Demakis JG Rahimatoola SH.: Peripartum Cardiomyopathy,
44:964-968: 1971.
Veille JC.: Peripartum Cardiomyopathies: A Review.
Am J Obstet Gyn 148:805-818, 1984.
Circulation
-
123
SUFENTANYL EPIDURAL ANALGESIA FOR OSSTETRICS
Ross ?layfield,
M.D.* and Robert
St. John’s
Mercy Medical
Center
St. Louis,
Missouri
63141
N. Miller,
8571
M.D.
Introduction:
We have used Epidural
and intrathecal
narcotics
for
(SF) was
obstetric
patients
since
May, 1979; Sufentanyl
introduced
into
our clinical
practice
in September,l984.
Five
have received
SF through
hundred
thirty
eight
(538)
patients
indwelling
lumbar epidural
catheters(LEC)for
labor,
delivery,
supplemental
analgesia
for cesarean
section
and postoperative
pain relief.
Patients
are informed
at prenatal
classes
of options
for pain relief
during
labor.
>90% of patients
attended
psychoprophylactic
preparation
(PPP) for natural
childbirth.
Methods:
placed
at the
L2-3 or L3-4
During labor
(LEC) was
analgesia-anesthesia
(LEAA).
interspace
for lumbar epidural
with lidocaine
and epinephrine
(epi)
was
Appropriate
testing
used.
SF,10 pg. with
hupivicaine
(bup)
and
IO
mg
epi.
10 !ng.
(6ml)was
injected
through
LEC. Following
bolus
dose,
patients
<5 cm cervical
dilation
were given
an infusion
of either
5pg
SF and 7mg bup./hr
or 7 mg bup./hr.
Women undergoing
cesarean
After
delsection
were anesthetized
with bup. or Nesacaine.
ivery
of the
newborn,
was injected
via LEC.
10 )Lg SF (4 ml)
Patients
were observed
for
intensity
and duration
of
onset,
analgesia.
Newborns were assessed
by delivery
room nurses
for
Apgar Scores.
Friedman
curves
and effects
of SF on duration
of labor,and
side
effects
attributed
to narcotics
were noted.
Fetal
monitors
were used in all
pts.
Results:
significant
relief
of
All patients
(1002)
received
pain with the initial
dose of SF. Bup. was used for more complete
analgesia
(per patient
request)
in <4% of all
patients.
The onset
of LEAA was 6 + 1.5 min. For prolonged
labor
infusion was
used
after
SF Eolus.
40% of
patients
required
one
supplemental
bolus
of
either
10)gSF or 15 mg bup.
Frequency
and intensity
of uterine
contraction
was not altered.
Maternal discomfort
or N/V following
delivery
via
c-section
was
decreased
from 45% !+ith LEA to < 10% with LEAA supplement.
Apgar scores
at 1 and 5 min. were never
< 7 regardless
of the
interval
of SF bolus
to
delivery
or total
infused
amount of
SF given
in this
protocol.
Conclusions:
Sufentnnyl
LEAA offers
significant
advantages
Ger
local
anesthetic
LEA during
labor
and delivery.
As well,
it increases
the comfort
of women during
cesarean
birth.
The
rapid
onset,
intensity
of analgesia
with minimal
side
effects
effects,
qualifies
SF as uniquely
suited
for women in labor.
121
8572
SAFETY
AND EFFICACY OF EPIDURAL FENTANYL
"PRELIMINARY
REPORT"
FOR LABOR
PAIN
Authors:
Murakawa K, Abboud
Henriksen EH
Affiliation:
Obstetrics and Gynecology,
Departments
of Anesthesiology,
Los Angeles County-University
of Southern California
Medical Center, Los Angeles, California 90033
TK*,
Yonekura
ML, Yanagi
T, Sarkis
F,
Introductio
:
Epidural morphine for labor does not produce satisfactory a"algesia?r2
possibly due to its low lipid solubility.
Fentanyl
being more lipophilic
than morphine, can diffuse readily across the dura
into the subarachnoid
space and hence may produce better analgesia.
Also, being less hydrophilic
than morphine,
it is less likely to remain
in the cerebrospinal
fluid in concentrations
capable of producing
side
effects.
I" the present clinical trial we investigated
the efficacy and
safety of epidural fentanyl in 5 parturients.
Methods:
Five healthy parturients
received 50 pg of fentanyl in 10 ml
of saline through a lumbar epidural catheter during the active phase of
labor.
The study was approved by the Human Research Committee and informed consents were obtained.
Uterine activity and fetal heart rate
parameters were monitored
continuously.
Pain intensity and relief were
evaluated using the visual linear analog scale, also a" investigator
independently
assessed pain intensity and relief.
Maternal vital signs
and the incidence of side effects were recorded just before injectlo"
of
fentany1, every 15 minutes for one hour, and every 30 minutes until
delivery.
Thereafter,
hourly observations
were made up to 24 hours.
Maternal venous blood gases were obtained prior to fentanyl injection
and every 4 hours after injection until the time of delivery.
The condition of the infant was evaluated
by Apgar scores at 1 and 5 minutes,
umbilical venous and arterial acid base status and the Neonatal Neurologic and Adaptive Capacity Scores (NACS) at 15 minutes, 2 hours and 24
hours after birth.
Results:
All patients had satisfactory
pain relief during labor with
a" onset of 8?2 minutes and a duration of 99?20 minutes Cfl?SE). NO"e
of the patients experienced
any side effects or changes in vital signs.
Epidural fentanyl did not adversely affect Apgar scores, acid base status
or the NACS of the neonate.
Discussion:
Epidural fentanyl provided Batisfactpry
pain relief with
rap1'd onset and no side effects, but since Its duration of actlo" is
relatively
short, epidural fentanyl by itself is not adequate for labor
analgesia.
Further work is needed to evaluate its safety and efficacy
when combined with local anesthetics.
References:
1. Husemeyer RP, O'Connor MC, Davenport HT:
Failure of epidural morphine
to relieve pain in labour.
Anaesthesia
35:
161-3, 1980.
2. Writer WDR, James FM III, wheeler As:
Double-blind
comparison
of
morphine and bupivacaine
for continuous
epidural analgesia
in labor.
Anesthesiology
54:
215-9, 1981.
122
.-.
Title:
EPIDURAL BIJTORPHANOL FOR ANALGESIA DURING LABOR AND DELIVERY
Authors:
Naulty JS: Gissen D, Malinow AM, Hunt CO, Ostheimer GW,
Datta S.
Affiliation:
Department of Anesthesia, Brigham and Women's Hospital,
Harvard Medical School, Boston, Massachusetts
02115
8573
Introduction.
Butorphanol, a u agonist-antagonist and kappa agonist
opiate, has been employed as a systemic analgesic during labor and delivery,'
and epidural butorphanol has been shown to be an effective and safe analgesic
technique following cesarean delivery. 2 However, little information is
available about the maternal and neonatal effects and efficacy of epidural
butorphanol for analgesia during labor and delivery. Therefore, we have
performed a double-blind, randomized dose-response study of this technique in
parturients at our institution.
Methods. The protocol was approved by the hospital's committee for the
protection of human subjects and written informed consent was obtained from
the patients when they were in early labor. All patients were ASA Class 1
multiparae, who requested epidural analgesia for pain relief, and who had a
pain score on a 1Ocm linear analog of pain scale of at least 5. An epidural
catheter was placed at the second lumbar interspace and lOm1 of .25% bupivaCaine to which was added 0,1,2, or 3mg of preservative free butorphanol was
injected in 2-3ml increments. The amount of butorphanol added was unknown to
the anesthesiologist performing the block or evaluating the patient's response.
Sensory levels, motor block, pain scores, vital signs, cervical dilation and
descent, uterine activity, and fetal heart rate were recorded at 5, 10, 15
and 30 minutes, and every 30 minutes thereafter until delivery was accomplished
and the patient discharged to the postpartum floor. Umbilical blood gases were
obtained at delivery, Apgar scores were recorded, and Brazelton neonatal neurobehavioral assessments were performed on the neonate at 4 and 24 hours post
partum.
Results. To date, 7 patients have been studied. Complete results of the
studybe
available at the meeting, but preliminary analysis has revealed
that the onset of complete analgesia (pain score of 0) is more rapid if at
least lmg of butorphanol is included in the local anesthetic solution, and
the duration of complete analgesia is approximately 2-3 times longer in the
patients who neceived epidural butorphanol. Motor block is much less evident
in the patients who received butorphanol.
The only significant side effect
observed has been somnolence, which appears to be dose-related,
Discussion.
Preliminary data analysis suggests that butorphanol is a
useTu1 adJunct to epidural bupivacaine for analgesia during labor and delivery, because it hastens the onset of complete analgesia and prolongs the
duration of the block, accompanied by the development of a less intense
motor block.
References.
1. Pittman KA, Smyth RD, Losada M et al.: Human perinatal distribution of
butorphanol.
Am J Obstet Gynecol 138:797-800, 1980.
2. Naulty JS, Weintraub S, McMahon J et al.: Epidural butorphanol for post* _.
cesarean oelivery pain management.
Anesthesiology 61:A415, 1984.
123
Title:
DURATION OF RESPIRATORY
ANESTHESIA
IN DOGS
Authors:
Ravindran
RS,*
Affiliation:
Department
Medicine,
of Anesthesia,
Indianapolis,
O’Neil
Bupivacaine
is
Introduction.
thetics
in obstetrical
anesthesia.
respiratory
paralysis
anesthesia,
PARALYSIS
NR,
Baldwin
Indiana
Indiana
FOLLOWING TOTAL SPINAL
SJ
University
46202
School
of
of the commonly used local
anesDuring
the performance
of epidural
could
occur
following
inadvertent
spinal
The duration
of such
injection
of large
volumes
of local
anesthetic.
It
is also
not known whether
the
respiratory
paralysis
is not known.
addition
of epinephrine
to the local
anesthetic
might
increase
the
duration
of respiratory
paralysis
in these
situations.
The purpose
of
this
study was to determine
the duration
of respiratory
paralysis
following intentional
total
spinal
anesthesia
in dogs.
Methods.
Twelve
mongrel
dogs (10 to 16kg)
were utilized
in this
The
dogs
were
sedated
with
intravenous
administration
of 8 mg/kg
study.
Percutaneous
lumbar
puncture
was performed
utilizing
a
of ketamine.
22-g
spinal
needle
in the L5-L6
interspinous
space.
In 6 dogs (Group
1)
total
spinal
anesthesia
was induced
with
subarachnoid
injection
of 6 to
8ml (depending
on the length
of the dog) of bupivacaine
0.5%.
The other
6 dogs (Group
2) received
bupivacaine
0.5% with
1:200,000
epinephrine.
Following
the onset
of total
spinal
anesthesia,
the tracheas
of the dogs
were
intubated
and positive
pressure
ventilation
with
100% O2 was initiated.
A femoral
arterial
line
was placed
and the systolic
blood
pressure
was maintained
over
100 torr
with
the administration
of fluid
and/or
intravenous
ephedrine,:,
Positive
pressure
ventilation
was
interrupted
at 15 minutes
following
the subarachnoid
injection
and at 5
minutes
intervals
thereafter.
The onset
of spontaneous
as well
as
adequate
ventilation
(TV
100ml)
was observed
for.
If inadequate
spontaneous
ventilation
was noted,
then
the mechanical
ventilation
was
resumed.
Results.
Total
spinal
anesthesia
was induced
in 2 to 3 minutes
in all
dogs.
In most of the dogs total
paralysis
was confirmed
by the complete
relaxation
of the vocal
cords
as well.
The duration
of respiratory
paralysis
is given
in table
1.
The mean duration
of respiratory
paralysis
was 50.8
minutes
in Group 1 dogs,
and 45.0
minutes
in Group 2 dogs.
Statistical
comparison
was made using
Student’s
t-test.
Conclusion.
In the study
the mean
duration
of respiratory
paralysis
following
total
spinal
anesthesia
was
NO.
bupivacaine
bupivacaine
noted
to be 50.8 minutes.
There
was
min.
with
epi
(min
no significant
difference
(p).2)
in
the duration
of respiratory
paralysis
1
40
30
in the animals
that
received
the local
:
;:
115
25
anesthetics
with
or without
epinephrine.
The duration
of respiratory
4
zz
15
paralysis
is similar
to the duration
that
we have observed
in 2 patients
65
30
60
25
(60 minutes).
one
mean
50.8
P> 0.2
124
.
8574
45
_.
_
Title:
PLACENTAL
PIGS
Authors:
Santos
Affiliation:
Departments
of Anesthesiology
Obstetrics
and Gynecology,
College
of
Physicians
and Surgeons,
Columbia
University,
New
York,
N.Y.
and
Department
of Obstetrics
and Gynecology,
Cleveland
Metropolitan
Hospital,
Case Western Reserve University,
Cleveland,
Ohio.
A*,
TRANSFER
Morishima
OF MIDAZOLAM
HO, Pedersen
AND
H, Finster
DIAZEPAM
M and Kuhnert
IN GUINEA
BR.
Midazolam
(MZ)
is a new, short-acting
benzodiazepine,
more water
Introduction.
Non-pregnant
patients
induced with MZ showed
soluble and potent than diazepam
(DZ).
greater
cardiovascular
stability
than those receiving
thiopental.
This property
would be
of value
in obstetric
patients
in whom intubotion
under
light
planes of anesthesia
frequently
results
in a substantial
rise in blood pressure
and possible
decrease
in
placental
blood flow.
Fetal
blood concentrations
of MZ following
IV injection
to
In one study, UV/MA
ratio was 0.6 for MZ and 0.8
pregnant
sheep have been reported.
for DZ (I).
In the other, the fetal arterial/maternal
venous blood ratio for MZ was 0.15
(2). This study has been undertaken
to elucidate
whether
the relatively
low F/M ratio of
MZ blood concentrations
is indicative
of restricted
placental
transfer
of this drug.
Methods.
Pregnant
guinea pigs were given an intravenous
injection
!I mg/kg)
of
either MZ or DZ over I min <in preliminary
studies this dose had been found not to result
in significant
arterial
hypotension
or oversedation).
At predetermined
intervals
varying
from I to 60 min after the end of injection,
they were stunned and killed by immersion
into liquid
nitrogen.
After
rewarming,
fetuses
were
removed
by hysterotomy
and
weighed.
Blood samples
were obtained
from both mother
and fetuses
by cardiac
puncture.
These were centrifuged
and plasma separated
and frozen until drug analysis.
Fetal brain was removed and frozen as was the remaining
fetal body.
Plasma and tissue
samples were analysed
for DZ or MZ and its major metabolite,
I-OH-methylmidazolam,
using high pressure liquid chromatography.
In the maternal
plasma, mean MZ concentrations
tended to be higher than
--Results.
those of DZ.
For example,
at 5 min they were 21 I.0 f. 60.5 (SE) and 45.0 t 9.5 ng/ml,
respectively.
In contrast,
fetal plasma concentrations
of both drugs were similar.
As a
result, the F/M ratio for DZ was higher, 0.88 vs 0.53 at 5 min. Yet, the proportion
of the
dose transferred
to the fetuses was similar
for both drugs (2-40/o per 100 g). Fetal brain
tissue concentrations
and the proportion
recovered
from that organ between 5 and 60 min
tended to be higher after MZ (0.1-0.39/o per log vs 0.03-0.20%
per log after DZ).
The
analysis of metabolite
is pending completion.
Conclusions.
In pregnant guinea pigs, the lower plasma F/M ratio of MZ, compared
to
that of DZ, was not associated
with more restricted
placental
transfer
of MZ.
It is also
noteworthy
that after 5 min MZ concentrations
in the fetal brain exceeded those of DZ.
I.
2.
References.
Conklin
KA, Graham CW, Murod S, Randall
FM, Katz RL, Cabalum
T, Lieb SM and
Brinkmon
CR: Midazolam
and Diazepam:
maternal
and fetal effects
in the pregnant
ewe. Obstet Cynec 56: 47 l-474,
1980.
Vree
TB, Reekers-Ketting
JJ, Fragen
RJ, and Arts
THM:
Placental
transfer
of
midazolam
and its major metabolite
I-hydroxymethylmidazolam
in the pregnant ewe.
Anesth Analg 63: 3 l-34,
1984.
125
8575
-
Title:
EPIDURAL ANALGESIA FOR LABOR AND DELIVERY: A
COMPARISON OF INTERMITTENT DOSES OF 0.25%, 0.375% AND
0.5% BUPIVACAINE
Authors:
Santos DJ,* Denson DD, Sweikert
Affiliation:
Department
of Anesthesiology,
School, Cincinnati, Ohio
T, Hammer
University
8576
S
of Cincinnati
Medical
Introduction.
The purpose of this study was to determine
the efficacy, safety and
doses
of
0.25%,
0.375%
and 0.5% bupivacaine
acceptability
of intermittent
administered
during epidural analgesia for labor and vaginal delivery.
Methods.
The study was approved by the Institutional
Review Board for Human
Research.
Informed consent was obtained from 36 healthy parturients
presenting
in
early labor for vaginal delivery.
The patients were sequentially
assigned to receive
bupivacaine
through a lumbar epidural catheter
according to the following groups:
I - 0.2516, II - 0.375%, and III - 0.5%. The patients received the same concentration
throughout labor and delivery.
Three ml. venous samples were obtained prior to and 20
minutes
after each epidural
injection
and assayed for bupivacaine
as previously
reported(l).
Maternal and umbilical venous samples were obtained at delivery.
Extent
of sensory and motor blockade was assessed 30 minutes after each injection and at
delivery.
Data were tested for normalcy of distribution
using a Shapiro-Wilk test.
Resulting data were further analyzed using either a parametric
or nonparametric
oneway analysis of variance followed by the appropriate
critical value test for multiple
comparisons.
A p < 0.05 was considered the minimum level of significance.
Results.
The three groups showed no statistically
significant
difference
in age,
parity, weight, height and cervical dilatation at the time of epidural placement.
Data
analysis
shows no difference
in the total
dose of bupivacaine,
highest
drug
concentration
(Cmax),
delivery
concentration
(Dconc),
number
of
doses,
fetal/maternal
drug ratio (UV/MV), duration
of anesthesia
(from induction
of
anesthesia
to delivery),
labor and perineal
analgesia
and extent of motor block.
Despite the lack of statistical
significance
between
the three dosage schedules,
increasing
motor block was noted with increasing
concentration.
There was also a
trend toward increased total dose with higher bupivacaine concentration.
Conclusion.
Based on the results
of this study,
we conclude
that equally
satisfactory
analgesia
can be obtained
from the use of 0.25%, 0.375% and 0.5%
bupivacaine.
There was no evidence of local anesthetic
toxicity or accumulation.
The
fetal/maternal
drug ratio (UV/MV) compared
well with those reported
by others.
Despite absence of statistical
significance
in the drug concentration
and motor block
in the three groups, an increase
in total dose and motor block was noted with
increasing concentration.
Since the analgesia obtained with 0.25% is not significantly
different
from that of higher concentrations,
it makes sense to use the lower
concentration
whenever possible.
References.
1. Denson CC, Knapp RM, Turner P, Thompson G: Serum bupivacaine concentrations
in term parturients
following continuous
epidural analgesia
for labor and delivery.
Ther Drug Monitor 6:393-398, 1984.
_~
.-
-
~-.
126
-
8577
JeffUnlvex’sity,
Philadelphia,
PA.
It is kxwn that drq dependent warer (LlW) have 81 increased Incidence
of
medical and obstetrlcdl
cm~licatims,
Lult little
infonnatim
exists 0, the
intraprtun
co.rse
md ranagetent of these patients.
Within the cmtext
af
FanI3.y Gznter, a cllnic.?Ll ZUKIresearch prqrar providing chive
preand postnatal services
for m wd their infmts,
a study was w&rtakm
to
detennineiftheDan’badDJrmalpat~cJflabar8difst~in~
mmagermt is apprqr~te.
lW study pspilatim
included 336 whc delivered
betwea Janzny 1982 md July 1984, of’ which 112 IIH (72% receiving mzthat!memintenmce).lbecanparismgrarpof
224rm~dependart-vas
matched Ior gravity,
parity md saicecmardc
back@amd.
lhe incidence
of $remature delivery,
abruptio placentae,
breech presentatim
axd intra&.erine
wh
retadaticm
were s$W’icatly
greater in the IfM. The average duration of the
first,
second and third stages of labor conpared 1.~11 with the nxmal couvse
of laba md matched the results of the conpwism
group. L&a- abrnnnalities
were of no greater incidence,
but thex WIY IWIP t.hm
wd cesarean sectiax
&rice a6 mmy fcnceps deliveries
which coincides tith the 40% increased use
of epidural anesthesia.
Analgesia Wd anesthesia !&ZE in excess of that xfiich
is given to the average patient.
lkx
were thee stillbxms , me nxmat2.l
death, md me maternal death. Apgar scopes and the incidence of fetal distress
.md recmiw~ staining were identical
in both grwps. Pastpartur canplicaticns
wa+z mape caxrrx in the cwi, but most were seccndary to the use of subclaiar
intravenous liws
inserted due to tht pxsmce
of sclerotic
veins. These data
rmggest that high risk prmata.l managaDent ax! car&W rmitcrm
in the intxaand Fostpartur paicds
utilizing
epi&%l
anesthesia identifies
wd usoaQ+
prevents UntcwarC cmplicatims
in KfIi.
127
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