Guidelinesfor the Managementof DiabeticKetoacidosis Definitionof DiabeticKetoacidosis D K A II. Hyperglycernia Ketonemia/ketonuria Acidosis Blood sugar> 200 mg/dl p H < 7 . 3o r I I C O j < l 5 n r E q / l - Pathophysiolosy Insulindeficiencyhasthreemain effects: L Lossof insulin-dependent glucosetransportinto peripheraltissues 2. Increasedgluconeogenesis in the liver 3. Increasedbreakdownof fat, protein,andglycogen Thus, insulin deficiency results in hyperglycemia(from increasedhepatic glucose prodttctionand decreased peripheraluptake)and acidosis(primarily derivedfrom hepatic fatty acidoxidationinto ketoacids). Ilyperglycetniaabovethe renal threshold(>180-200mg/dl) resultsin glycosuria. This producesan osmoticdiuresisthat dragssolutes(Na, K, Cl, PO4)along with it, leadingto dehydrationand electrolytelosses. With significantdehydration,there may be poor perfusionof peripheraltissuesleadingto lactic acidosis,which further aggravatesthe existingketoacidosi s. I II. Assessmcnt A. History Tlte classic symptornsof new-onsetdiabetesmellitus are polyuria, polydipsia, and polyphagiaaccompaniedby weight loss. Theremay be a history of weakness,malaise, or lethargy. Often the acute crisis will be precipitatedby an acute infection or stress. Nausea,vomiting, abdominal pain, alteredbreathing,or progressiveobtundationmay precipitatethe visit to the EmergencyDepartment. In children known to have diabetes, DKA is usuallypreventable.It is often precipitatedby poor compliancewith the home managcmcntroutitrcor failureto increaseinsulindoseswith an intercurrentillness. B. PhysicalExarn l. Airway -- may be compromisedin patientswith extremeobtundation.Consideration shouldbe given to intubationand mechanicalventilationif the patientis not making adecluate respiratorycompensation for the metabolicacidosis. DKA Guidelines 25-April-06 2. Breathing-- typically deep,hyperpneic(Kussmaul). Breathsoundsshouldbe clear; ralcs/rhonchirnay suggestintercurrentinfectionor pulmonarycdema(lvhich can be seenin the correctionof DKA). 3. Circulation-- particularattentionshouldbe paid to pulse,blood pressure,capillary refill, and any orthostaticchanges. Childrenwith DKA are hyperosmolar,so that intravascularflLridsare sparedat the expenseof cellular fluids. Therefore,the clinicalexatninatiotr underestimates the degreeof dehyclration. 4. Mental status-- A lull neurologicalexaminationmust be performedon all patients presentingin DKA, so that a baselinemay be establishedto which subsequent examinationsmay be compared. Acute deteriorationsin menlal statusmay herald cerebraledema(seesectionon cercbraledema). 5. Abdonren -- many patients in DKA complain of abdominal pain, often due to persistentvomiting or ketosis. Tendernesstends to improve with treatment;pain which remainsor worsensshould prompt considcrationof other diseaseprocesses (e.g.,appendicitis). C. Initial laboratorytcsts The laboratory confirmation of thc cliagnosisof diabetes mellitus requires only a fingerstickblood sugar and urinalysisto confirm the hyperglycemia,glycosuriaand ketonuria,but in DKA additionallaboratorytestsare useful in assessingthe severityof illnessand guidingtreatment. 1. Electrolytes The sodium is typically low, as a result of urinary losses, hyperglycenria,and hypertriglyceridemia(artefactualhyponatremia). For every 100 mgldL glucoseabove200 mg/dl,, the measureNa shouldbe reducedby I .6 mEqil. N&.u..".t.,I : + 1.6 N&,r'r.nrur.,r x [Glucose]- 200 t00 Potassiummay be low, normal, or elevated,but the total body storesare always depleted. Bicarbonatevalues are usually low, consistentwith metabolic acidosis. BUN and Creatinineareusuallyelevatedwith dehydration.Glucoseis invariablyelevatedin DKA. 2. Venousblood gas -- will documentmetabolicacidosis. Arterial blood gas should alsobe consideredin the appropriatcsettingof severeclinical decompensation. 3. Calciunr.Phosphorus-- Phosphatelevels are usually low due to urinary losses. Iteplacementof phosphatein the rehyclrationfluids nray precipitatetetanyin patients with low calcium levels. If the initial calcium and phosphoruslevels are closeto normal,thereis no needto keeprepcatingthem. DKA Guidelines 25-April-06 IV. 4. CBC w/ differential -- ElevatedWBC countsand "left shifts" are often seenwith the acutc stressof DKA and do not necessarilyindicate an aoute infectiousprocess. Furthermore,significantinfectionmay be presentevenin the absenceof fever. 5. Additionallaboratorytestswill dependon the clinical situation. Goalsof Therapv In planningtreatment,it is irnportantto considerthe importantcomplicationsof DKA: A. Cardiovascularcollapse 1. Fromdchydration 2. Treatnrentinvolvesintravascularfluid expansionwith ISO'|ONIC fluids (saline) B. Overwhclmingacidosis l. From ketoacidproductionand lacticacid accumulation 2. Volurneexpansionand tissuereperfusionto oorrectlactic acidosis 3. Pronrptinitiationof insulinto stopfatty acid oxidationand ketoneproduction 4. Consideruse of sodium bicarbonatein patientswith arterial pH < 6.9 and/or evidenceof myocardialdepression C. Ilypokalcmia with rapidintracellularmovementof potassium l. lnsulin therapyis associated 2. Adequatepotassiumreplacement in rehyclration fluids and frequentmonitoring rvithbloodtestsand EKG's D. CerebralEdem:r L llypertonic dehydralionin DKA is associated with the productionof osmotically -(taurine, particles in the inositol active brain formerly "idiogenicosmoles")that act to preventneuronalcellulardehydration. 2. Correctionof hyperosmolarstateleadsto fluid influx into the brain. Rapid rates of rehydrationor correction of hyperosmolaritymay lead to cerebral cellular swellingand brain herniation.It usuallyoccurs6-18 hoursinto therapy,just as the patient appearsto be clinically and biochernicallyimproving. This is the most contntoncauseo-f'mortaliqtin children with DKA !!! 3. Muclr of the etiology and pathophysiology of cerebraledemais still unknown,but the risk shouldbe niinimizedbv attentionto the followins: (over48 hrs) with isotonicfluids a. Slorvfluid replacement b, Irrequentmonitoringand slow rise of calculatedCORRECTEDNa values c. Close neurologicsurveillancefor early signsof increasedICP (headache, lethargy,slurredspeech,obtundation)and rapid evaluation& action DKA Guidelines 25-April{6 V. 'Ireatment A. Initial Resuscitation Obviously, adequate airway patency and brcathing should be assessedfirst, and immediateinterventionsmade as needed. Initial fluid resuscitationshould always be witlr normal saline, 10-20 cclkg. Remember.rapid fluid replacementis potentially dangerous,so thotrghtfirl considerationof fluid needs should guide treatment,not "automatic"reaotions.After each l0-20 cclkg aliquot,pulse,blood pressure,orthostatic The aim is changes,intake/output,perfusion,and blood glucoseshouldall be reassessed. lrot to completelynormalizethe vital sigrisbut to ittrprovethem. B. Insulin The initial doseis usually 0.1 Units/kg/hour.For profoundhyperglycemia(BG > 1000) lower rates(0.05-0.75Units/kg/hr)may be preferable.The goal is to or hyperosmolarity, lower the serumglucoseby 50-100mg/dl/hr. When the blood sugar falls below 250 mg/clt., dcxtrose should be added to the rehydrationfluids. A "two-bag" infusion system, in which one bag containsDro is convenientfor titrating the slorv, (+electrolytes)and the other D6 (+-electrolytes), glucose. scrttm steadydcclinein Two - bag sysfetn for DKA (t) DoNS KCI + KP04 (2) DroNS KCI + KP04 'Ihe llrst bag (l) contains nornral saline and some concentration ofKCl and K-Phosphate. The second bag (2) contains the s a m e c o n c e n t r a t i o no f e l c c t r o l y t e s ,b u t a l s o h a s D l 0 . T h e t r v o s y s t c m s a r e n l n o n s e p a r a t cp u m p s u r d Y ' d i n t o t h e p a t i e n t . D e x t r o s e c o n c e n t r a t i o n sn r a - vt -l r u s b c t i t r a t c d r a p i d l y t n d e a s i l y a s n e e d e d : e . g . , r u n n i n g b a g ( l ) l t 10 0 c c l h r a n d ( 2 ) a t 0 c c / h r - n o d c x t r o s e ,r v h i l e r u n n i n g b o t h a t 5 0 c c l h r g i v e s a f i n a l c o n c e n t r a t i o no l ' D 5 . DKA Guidelines 25-April-06 C. Acidosis The most importantstepsin treatingacidosisare the prompt institution of insulin and adequatefluid resuscitationfor tissue reperfusion. Sodium bicarbonateshould be if: considered 1. Arrerialpl l < 6.9 'fhere 2. is evidenceof cardiovasculardysfunction,such as poor contractilityor peripheralvasodilation The dosemay bc calcul:rteby the formula Dose(mliq): weight(kg) x 0.3 x (15 - [HCOr1) Alternatively,a reasonable doseis l-2 mEq/kg. Bicarbonateshouldalwaysbe given as a SLOW infusion over l-2 hours, not as a bolus. Rapid pH changesmay precipitate hypokalemiaor cause a paradoxicalCNS acidosis(which may worsen the patient's mental status). Failure of the acidosisto improve in responseto bicarbonatesuggests inadequate volume status.respiratorycompromise,or severesystemicinfection(sepsis). Recentevidencehas called into questionthe utility of bicarbonateadministration.and most studiesshorv that bicarbonateuse does not hastenresolutionof DKA or shorten hospitalizations. D. Rehydration fluids Dehydrationin DKA is predominantlyintracellular. Clinical estimatesof percent 'l'herefore, dehydrationare often highly inaccurate. CLOSE MONITORING OF INTAKE/OUTPUT AND FREQUENT REASSESSMENT OF FLUID NEEDS is critical. Calculationsshould aim to restorethe fluid deficit slowllr and evenly over 48 hours. The fluid replacementrate must be titrated to the clinical setting; i.e., the calculatedNa rate should RISE with treatment. A FALL IN T'HE CALCULATED SODIUM SHOULD PROMPT AN IMMEDIATE DECREASE IN THE FLUID RATE. Resuscitationfluids should be subtractedfrom the fluid deficit. Replacementof fluids for urinary lossesis not needed,bccauseurinary lossesare usually negligibleafter the first several hours of treatmcnt. THE RESUSCIT'ATIONFLUID SHOULD ALWAYS BE NORMAL SALINE. Thereafter,normal saline and'/, normal saline can be used,although we prefer nonnal saline. Hypotonic fluid replacementincreasesthe risk of cerebral edema. In prolbund hypernalremia, 213 or 3/4 NS may be considered after the hyperglycemiahasbeencorrected. DKA Guidelines 25-April-06 E. Electroll'tcrcplacenrent 1. 2. Sodium- Total body Na deficit of 8-10 mEq/kg as a result of osmoticdiuresis. Calculationof dellcits and rcplacementsare generallynot needed. The initial rehydrationfluids in DKA should almost always be normal saline to protect againstcerebraleclema,changedto 3/aor t/znornlal salineas neededlater. 'l'otal body K cleficitof 8-l0 mEq/kg as a result of osmoticdiuresis. Potassium-f-lor.vever. serllmK+ may be normalor evenelevated,becauseacidemiacausesa II+/K+ exchangethat rnoves K+ out of the cells into the intravascularspace. ScrurnK+ falls r.viththerapy,becauseof correctionof acidemiaand the direct action of insulin on cellular K+ uptake. Potassiumshould be added to the replacenrent lluids as soonas the abscnceof renalfailureis shown: K+ < 3.0mEq/L K + : 3 . 0 - 6 . 0m E q / t , K+ > 6.0mEq/I. 60 mEq/L 40 mllq/L holdK Occasionally,replacementratesas high as 80 mEq/L may be needed.Rates> 80 mEq/L shouldbe given via centralvenousaccess. Potassiumreplacementrates greaterthan 0.5 mEq/kg/hrshouldbe avoided. Serumpotassiumlevelsshouldbe known beforeinsulin is given. FormalIIKG shouldbe consideredin patientswith serumpotassiumlevels< 3.0 or -' 6.0 mEq/L. 3. Phosphate-- To correct phosphatedepletion, and to prevent hyperchloremia (rvhich often occurs during treatmentof DKA), the potassium is generally replacedas: PotassiumChloride* PotassiumPhosphate, in a l:1 ratio This methodoffers the advantageof replacingphosphate,which improvesoxygen and energydelivery,throughthe formationof ATP and2,3-DPG. Calcium shouldbe monitoredwhen receivingsupplementalphosphate. ** If potassiumphosphateis not available,standardKCI may still be given +* VI. Monitorins Treatmentof DKA requiresfrequenteyes-on.hands-on,brain-onreassessment. DKA should never be "auto-pilot" or managedfrorn the call room. Frequentbedside review of clinical data, includingvital sign changes,perfusion,mental status,I/O's, and labs.is essential. DKA Guidelines 25-April-06 A. Neurologicalreassessment shouldbe performedq lhr B. Blood glucoseshouldbe measuredqlhr while on an insulin infusion C. Electrolltesq2hr until calculatedNa and K arenormal and measuredHCO3> 15, then q4hr until infusionsare d/c'd. More frequentmonitoringmay be necessary if the calculatedNa falls at any time. D. BuN/Creatinine, calcium and phosphorusno more frequently than q4-6hrsunless clinically indiczrted. E. Serial measurementsof arterial pl{ may be necessaryin intubatedpatients,those with extreme life-threateningacidosis,or after bicarbonatetherapy. These patientsshould have intra-arterialcathetersplaced and be monitored in the ICU. SerialVBG's may be discontinuecl onceHCOr > 15. F. All patientsshouldbe on telemetry. G. Central venous cathetersshould be consideredin patients with evidenceof impairedrenal function,pulmonaryedema,or in other situationsof complicated fluid management. H. Intracranialpressuremonitors ("bolts") should be consideredin any patient with cerebral edema and neurologic deterioration. Immediate brain imaging and neurosurgical consultationarerequiredin this setting. VII. The Hieh-Risk Patient Patientswith the following characteristics may requireICU admission: A. B. C. D. E. F. G. H. DKA Guidelines Age<3years Significantlyalteredor deterioratingmentalstatus pH<7.2 Glucose> 1000mg/dl Na (calculated)> 160or any patientwith falling (calculated)Na K < 3.5 mEq/L on admission > 350 mOsm) Severehyperosmolality(Sor,n Otherorgansystemdysfunctionthat complicates treatment 25-April-06 VIII. Transitionto Subcutaneous Insulin A. When dehydration,acidosis and hyperglycemiaare corrected(glucose< 300 mg/dl,pl-l > 7.3, tlClOr > 15).and patientis clinically hydratedit is time to begin feeding the patient and plan for subcutaneous insulin. The patient should be changcdto subcutaneous insulin afler toleratingoral nutrition well, and at a time of a major meal(breakfastor dinner). B. Subcutaneous insulin may also be starleddirectly in new onsetDM. if the patient is not in kctoacidosis. fbr initialdosesas lbllows: C. Guidelines l. Total dosefor day : 1.0unit/kglday 2. AM:213 of total dosewith ll3 as Humalogand2l3 as Lente (if child is <6yo, useNPH insteadof [-ente) 3. PM: 1/3 of total dosewith ll2 as Flumalogand l/2 as Lente (if child is <6yo. useNPII insteadof I-ente) The insulin drip sltould be discontinued 30-60 min after the first dose of subo insulin 4. Adjust AM anclPM dosesdaily basedon fingerstickglucoselevels until glucoselevelscomeinto the normalrange(70-l20rng/dl). This may rcquireas much as 1.5u/kg/day(or more!) in the hospital IX. Summary The mortality rate of DKA in children,despiteall that we know, continuesto be 3-5%. One must never be lulled into a "cookbook" approachto DKA. This referenceservesas a guideline, not a protocol, for therapy. It does not replace an understandingof the pathophysiologyunderlyingDKA, vigilant surveillance,and active modificationof the treatmentto prevailingcircumstances. DKA Guidelines 25-April-06
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