1. science
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290
ORIGINAL ARTICLE
Conversion of laparoscopic to open cholecystectomy, is
gender a predictor?
Farzana Memon, Roger Christopher Gill, Sumera Baloch, Mehmood A. Khan, Amber Bawa, M.
Saeed Quraishy, Noman Shehzad
Civil Hospital Karachi
F Memon
S Baloch
MS Quraishy
Aga Khan University
Hospital, Karachi
RC Gill
A Bawa
N Shehzad
Rangers Hospital,
Karachi
MA Khan
Correspondence:
Dr. Farzana Memon FCPS
Associate Professor of
Surgery, Surgical Unit IV,
Civil Hospital Karachi
[email protected]
Abstract:
Background: It had generally been thought that male gender is associated with difficult cholecystectomies. Laparoscopic Cholecystectomy has been considered as a standard of care for
treating patients with gall stone disease. However increased difficulties are encountered when
males undergo surgery with increased conversion rates to open procedures.
Objective: The objective of our study was to analyze gender as predictor of conversion of
laparoscopic to open cholecystectomy and to also find out other factors predicting conversion
of laparoscopic to open cholecystectomy.
Material and methods: We conducted Retrospective Cohort Study at Surgical Unit IV Civil
Hospital Karachi. Record of all the patients who had undergone Laparoscopic Cholecystectomy from Jan 2013 to Dec 2013 were retrieved and reviewed. Patients were divided into two
sub groups based upon their gender. Exposed group included male patients with gall stones
disease and control group included female patients with gall stone disease.
Results: A total of 123 Laparoscopic Cholecystectomies were performed in the above mentioned period. 24%(30) of the participants were males while seventy six percent of the participants (93) were females. Mean age of the participants was 40 +/- 11.8 years. Mean age of males
was 45 +/- 14.5 years while that of females was 38.6 +/- 10.5 years, p value 0.028. 12 (9.8%)
patients required conversion of the laparoscopic to open procedure. The risk of conversation
of laparoscopic cholecystectomy to open procedure in male patients was 4.34 times those of
female patients which when adjusted for covariates including age and cholecystitis reduced
to 2.95 and did not achieve statistical significance. For male patients, adjusted relative risk for
operating surgeon to encounter difficulty during operation turned out to be 1.86 times than
those for female patients but this did not achieve statistical significance.
Conclusion: Male gender does exhibit increased difficulty and conversion to open procedures
while performing laparoscopic cholecystectomy however in our study they did not achieve statistical significance. Whether gender is an important risk factor to encounter difficulties and
increased conversions to open procedures still needs to be studied in prospective setting.
Keywords: Male gender, Conversion of laparoscopic to open cholecystectomy, Open procedures, Cholelithiasis
Introduction:
Since its advent in late 20th century, laparoscopic cholecystectomy is now the gold standard for
treatment of symptomatic gall stones disease1,2.
Laparoscopic approach to cholecystectomy
has several advantages over open procedure including less surgical trauma, less post operative
pain, small scar, early discharge from hospital,
early return to work and less chances of wound
infection. Common bile duct (CBD) injury is
the most dreaded complication of cholecystectomy. Rate of CBD injury in the earlier periods
of laparoscopic cholecystectomy was higher as
compared to open procedure. With experience
Pak J Surg 2014; 30(4):290-295
Conversion of laparoscopic to open cholecystectomy, is gender a predictor?
gained in this area, now CBD injury risk is rare
and is the same for laparoscopic cholecystectomy as for open cholecystectomy3-5. Despite advancement in experience and technology, laparoscopic approach to cholecystectomy may not
be possible in every patient. In these situations
conversion of laparoscopic procedure to open
procedure is required. Most common reasons
requiring conversion are bleeding not controlled
via laparoscopic approach, dense adhesions hindering dissection to the extent that either safety
is risked or progression of procedure is poor or
unintentional injury to surrounding structures
like liver and major bile ducts would take place
which may require conversion to open procedure. Various factors have been proposed by investigators around the globe, related to difficulty
in dissection and conversion to open procedure.
These include age, gender, obesity, comorbid
conditions, gall bladder wall thickness and inflammatory response6-10.
These are the factors based on which the difficulty encountered during laparoscopic procedure
may be predicted. Male gender has been seen as
an independent risk factors for difficulty in laparoscopic cholecystectomy in some of the these
studies resulting in higher conversions2,6,11,12.
There is also impression of male cholecystectomy being more difficult than female patients but
there are no reports to date from our population
to have in depth analysis of this perception.
The objective of our study was to analyze gender as predictor of conversion of laparoscopic to
open cholecystectomy and also to find out other
factors predicting conversion of laparoscopic to
open cholecystectomy.
Material and methods:
We conducted Retrospective Cohort Study.
Record of all the patients who had undergone
laparoscopic cholecystectomy from Jan 2013 to
Dec 2013 were retrieved and reviewed. Patients
were divided into two sub groups based upon
their gender. Exposed group included male patients with gall stones disease and control group
included female patients with gall stone disease.
Pak J Surg 2014; 30(4): 290-295
291
Main outcome measure was conversion from
laparoscopic to open procedure. Information
was collected from operative notes.
Secondary outcome measures were duration of
operation and surgeon’s subjective assessment
of difficulty of operation. Time of operation was
categorized into two categories as < 90 minutes
and > 90 minutes. Surgeon was labeled to have
encountered difficulty in operation if any one or
more of the following were encountered during
operation: difficulty in dissection at triangle of
callots, significant bleeding during operation,
and injury to surrounding structures.
Information was collected regarding age of the
patients, history of cholecystitis at the time of
presentation and history of choledocholithiasis
at the time of presentation.
This study was conducted at General Surgery
Department of Civil Hospital Karachi. Civil
Hospital Karachi is a public sector tertiary care
center.
Adult patients diagnosed with gall stones disease requiring elective laparoscopic cholecystectomy were included in the study. Patients of age
16 years and above were included in the study.
Diagnosis of gall stones disease included biliary
colic, acute cholecystitis, chronic cholecystitis,
Choledocholithiasis after CBD stones removal
through ERCP, gall stones pancreatitis requiring
cholecystectomy.
Diagnosis was confirmed using Ultrasound of
liver and gall bladder and laboratory investigations including complete blood count and liver
function tests.
Exclusion criteria were Patients diagnosed with
Gall bladder malignancy; complicated gall
stones disease like gangrenous cholecystitis, gall
bladder perforation; previous open abdominal
surgeries; missing data and operative procedure
other than laparoscopic cholecystectomy.
All procedures were performed under general
anaesthesia by standard four port technique.
Pneumoperitoneum was established by open
292
F Memon, RC Gill, S Baloch et. al
Hassan’s technique. All procedure were done
by either consultant general surgeon or residents under supervision of consultant general
surgeons. At our institutions, in case of cholecystitis, laparoscopic cholecystectomy is done
in the same admission if presentation is within
one week of cholecystitis and in case presentation is more than seven days after cholecystitis,
then cholecystectomy is planned after six weeks
of cholecystitis.
Approval from Institutional Review Board was
sought prior to starting the study. All the data
was collected in coded form with no identifiable
information collected.
Data was collected on pre-formed questionnaire
having information regarding outcome of interest and predictor variables. Data was recorded
in coded form. Hard copies were submitted to
research office of the Civil Hospital and were
kept under lock and key. Data was entered in
SPSS version 19. All the electronic form of data
was password protected. Hard copies of the
questionnaire are in the custody of Department
of Research of Civil Hospital Karachi and will
be shredded three years after the publication of
study.
Categorical variables have been reported in percentages and quantitative variables reported in
means +/- Standard Deviations. Univariable logistic regression was done to analyze impact of
main predictor variable and other predictor variables upon outcome of conversion to open cholecystectomy. Multivariate logistic regression
was run to analyze impact of predictor variables
on various difficulties encountered during surgery. P value of less 0.05 was considered as significant. To be included in multivariate logistic
regression analysis, p value of less than 0.2 was
considered significant. Adjusted relative risks
with 95% confidence intervals were reported.
Analysis was run to check for confounding and
plausible interactions.
Results:
A total of 123 Laparoscopic Cholecystectomies
were performed in the above mentioned period.
Twenty four percent (30) of the participants
were males while seventy six percent of the participants (93) were females. Mean age of the
participants was 40 +/- 11.8 years. Mean age of
males was 45 +/- 14.5 years while that of females
was 38.6 +/- 10.5 years, p value 0.028. Table 1
gives comparison of different variables between
two groups.
In our study, 12 (9.8%) patients required conversion of the laparoscopic to open procedure.
Relative risk of conversion from Laparoscopic
to open procedure is given in table 2.
All the predictor variables given in table 2 were
considered for multivariable analysis. Relative
risks of conversion from laparoscopic to open
procedure when adjusted for co-variates including age and cholecystitis at the time of presentation are given in table 2.
Potential interactions were checked between all
predictor variables, none of them turned out to
be significant and affecting the model. So analysis showed that risk of conversation of laparoscopic cholecystectomy to open procedure in
male patients is 4.34 time those of female patients when not adjusting for co-variates. Adjustment of co-variates including age and cholecystitis at the time of admission reduced this
value from 4.34 to 2.95 and adjusted value did
not achieve statistical significance.
Adjusted relative risk of males for length of surgical procedure was not statistically significant
and different from females. For male patients,
adjusted relative risk for operating surgeon to
encounter difficulty during operation turned out
to be 1.86 times than those for female patients.
Distribution and values are given in table 4.
Discussion:
Laparoscopic cholecystectomy is gold standard
treatment of uncomplicated symptomatic gall
stones2,13-22. Despite advancement in medical
technology and experience, there remain cases
in which difficulties are encountered during operation which may lead to conversions to open
procedure. Prediction of difficulty before operaPak J Surg 2014; 30(4): 290-295
293
Conversion of laparoscopic to open cholecystectomy, is gender a predictor?
Table 1: Comparison of Various Characteristic Between Two Groups
significance could not be achieved. This could be
due to insufficient power at the given sample size.
Variable
Males
(n1 = 30)
Females
(n2 = 93)
P Value
Age (Years)
45.1
38.6
0.028
Cholecystitis At Initial Presentation
4
8
0.48
CBD Stones Present at time of presentation
11
28
0.50
Table 2: Univariable Analysis reporting Un-adjusted Relative Risks of Predictor Variables
Variable
Relative Risk (95% CI of Relative Risk)
P Value
Gender (Male)
4.34 (9.38 – 13.67)
0.012
Age (> 40 Years)
4.53 (1.23 – 16.73)
0.023
Cholecystitis At Presentation
4.62 (1.39 – 15.36)
0.012
CBD Stones Present at time
of presentation
6.46 (1.75 - 23.87)
0.005
Table 3: Multivariable Analysis reporting Adjusted relative risks of Predictor Variables
Variable
Adjusted Relative Risk (95%
CI of Relative Risk)
P Value
Gender (Male)
2.95 (.92– 9.41)
0.068
Age (> 40 Years)
4.73 (1.22– 18.34)
0.025
Cholecystitis at Presentation
5.97 (1.74– 20.50)
0.005
Table 4: Adjusted Relative Risk with 95% Confidence Interval for Duration of Operation and
Difficulty Encountered During Operation
Outcome Measure
Male
(n = 30)
Duration of Operation 9 (30%)
> 90 min
Female
(n = 93)
Adjusted Relative Risk
for Males (95% Confidence Interval)
12 (13%) 1.64 (0.66-4.08)
Difficulty Encountered 20 (67%) 27 (29%) 1.86 (1.01-3.43)
During operation
P Value
0.29
0.045
tion helps prepare operating surgeon for logistics
as well as proper counseling of patient and family23. Active or past inflammation of gall bladder is known to increase the level of difficulty in
dissection and operative time4,29,38,39,42. Impact
of gender has been evaluated in different studies with varying results. Male gender is seen to
be associated with more difficult Cholecystectomies2,6,11,19,23,24,27-42. Our results at level of Univariate analysis show a significant increase in risk of
conversion from laparoscopic to open cholecystectomy in male patients. Age of the patient, history of cholecystitis and choledocholithiasis at
the time of presentation were also significantly
associated with increased risk of conversion from
laparoscopic to open procedure. When adjusted
for history of cholecystitis and age of patients,
still risk was greater for male patient but statistical
Pak J Surg 2014; 30(4): 290-295
Differences in humoral and inflammatory responses to body insult have been proposed as
the underlying causes of the observed differences in surgical findings29,35,38,39. There is more collagen and hydroxyl proline deposition seen in
the inflammatory response exhibited by males
and the decreased active estrogens within the
male blood may partly contribute to the excessive inflammatory response generated35. Estrogen the female hormone is known to lessen the
inflammatory response and prevent it from over
exhibition. Studies support the idea that estrogens may decrease the macrophage accumulation at the site of inflammation and resultant
fibrosis may contribute to the more vigorous
inflammatory response seen in males35,44. Others speculate that the difference in pain thresholds in both genders and anthropometric differences in body fat distribution and shielding of
gall bladder by the liver from anterior abdominal
wall may lead to inaccuracy in physical examination findings misleading the surgeon in estimating the severity and diagnosis in males29. There
is evidence that preoperative history, physical
examination and laboratory studies less reliably
predict disease severity in men29,45. The natural
history of gall stone disease is extensive inflammation and scarring leading to distorted gall
bladder anatomy including porta hepatis which
leads to difficulties in performing laparoscopic
cholecystectomy in safe manner and this is more
aggressively presented in males45,46.
Our findings that level of difficulty encountered
during laparoscopic cholecystectomy in male
patients is significantly greater than female patients is also consistent with finding reported
in literature. Our study reports risk of male
gender from our region which can help treating
surgeons in counseling the patients. It can also
serve as a benchmark study upon which further
prospective studies can be planned. It highlights
the importance of future considerations into the
genetic and molecular basis of this difference in
gender specific disease process. We recommend
future prospective studies to be taken up in or-
294
F Memon, RC Gill, S Baloch et. al
der to broaden understanding of surgeons as to
why males continue to exhibit difficulties in laparoscopic cholecystectomies despite improvement in technical side of the procedure.
Conclusion:
Male gender does exhibit increased difficulty
and conversion to open procedures while performing laparoscopic cholecystectomy however
in our study they did not achieve statistical significance. Whether gender is an important risk
factor to encounter difficulties and increased
conversions to open procedures still needs to be
studied in prospective setting.
Limitations:
We had retrospective data collection. Information was obtained from medical record which is
not maintained for purpose of research. Missing
information hindered us from extensively studying other potential confounders.
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