Management of Diabetic Ketoacidosis in the PICU PICU Resident Lecture Series

DKA - A common PICU diagnosis Incidence 4.6 – 8 per 1000 person years among people with diabetes Pediatric mortality rate is 1-2%

DKA causes profound dehydration Hyperglycemia leads to osmotic diuresis Often 10-15% down from baseline weight Profound urinary free water and electrolyte loss Free water follows glucose into urine Electrolytes follow free water into urine

Electrolyte abnormalities Pseudo-hyponatremia with hyperglycemia Sodium should rise with correction of glucose Profound total-body K+ depletion Urinary loss, decreased intake, emesis Initial K+ may be high due to acidosis, low insulin Aggressive K+ replacement necessary to prevent arrhythmias Phosphate, magnesium, calcium require replacement

Initial DKA management - ED Resuscitation aimed at shock reversal Begin with 10-20 mL/kg NS bolus, may repeat if signs of shock persist Bolus fluids only necessary if signs of shock present Avoid overly-aggressive fluid resuscitation Concern for inciting cerebral edema, though no clear data

Initial DKA management - ED NEVER give bicarbonate Increases risk of cerebral edema Begin insulin infusion at 0.1 units/kg/hr Should be initiated prior to leaving ED SQ or bolus insulin not indicated

Pre-PICU arrival Order several bags of dextrose-containing and non-dextrose-containing IVF pre-PICU arrival Often takes pharmacy 1 hour to custom-make IVF No dextrose-containing fluids stocked in PICU

Fluid Management - PICU 3 components to replacement fluids Deficit (often 10-15% total body water deficit) Ongoing losses (polyuria, emesis) Maintenance Possible to calculate the above, or give: 1.5X maintenance if moderately dehydrated 2X maintenance if severely dehydrated

Initial IVF Isotonic fluid with potassium NS + 20 mEq/L KCl + 20 mEq/L KPhos Start with 40 mEq/L of potassium if K+ < 5 K+ often split between KCl and KPhos to avoid hyperchloremic metabolic acidosis NS preferred to help prevent cerebral edema

Adding dextrose Add dextrose to IVF when glucose < 300 2 bag system allows titration of dextrose based on glucose Bag 1: NS + 20 KCl + 20 KPhos Bag 2: D10 NS + 20 KCl + 20 KPhos

Titrating dextrose 2 bag system example: Total IVF rate = 160 mL/hr Fingerstick glucose = 280 Bag 1: NS + 20 KCl + 20 KPhos @ 120 mL/hr Bag 2: D10 NS + 20 KCl + 20 KPhos @ 40 mL/hr Fluids “Y” together, dextrose concentration = D2.5

Titrating dextrose 2 bag system example: Total IVF rate = 160 mL/hr Fingerstick glucose = 180 Bag 1: NS + 20 KCl + 20 KPhos @ 40 mL/hr Bag 2: D10 NS + 20 KCl + 20 KPhos @ 120 mL/hr Fluids “Y” together, dextrose concentration = D7.5

Frequent lab monitoring is essential in DKA Glucose q1 hour Chem 10 , VBG q4 hours To correct venous pH to arterial pH, add 0.04 Serial UAs to monitor for resolution of glucosuria and ketonuria

DKA vs. Hyperglycemic Hyperosmolar Syndrome (HHS) HHS more likely in older, obese patients with Type II DM Lab features of HHS More severe hyperglycemia than DKA Less severe or absent acidosis Trace or absent ketones in urine Can have normal serum bicarb Serum osmolality > 320

Importance of Insulin Insulin is the only therapy that corrects the underlying pathophysiology in DKA Increase dextrose as necessary to continue insulin infusion at 0.1 units/kg/hr Do NOT titrate insulin drip

Transitioning to SQ insulin May consider transition when: Bicarb > 18, pH > 7.3, AG <12, GCS 15, emesis resolved How to transition – order of events: Fingerstick glucose pre-meal  eat meal  give SQ insulin  stop drip May re-check VBG post-meal to ensure that acidosis has not recurred

Complications of DKA Cerebral Edema Vasogenic vs. cytotoxic, unclear etiology Risk factors: Age <5 years High BUN (severe dehydration) Severity of acidosis Bicarbonate administration New-diagnosis diabetes Na levels don’t rise as expected with treatment

Cerebral Edema Hourly neuro / pupillary checks Mannitol 0.5 g/kg at bedside Consider 3% NaCl bolus 3-5 mL/kg if Na drops with therapy Stat head CT for any concerning mental status changes Give mannitol prior to going to CT! If CT reveals cerebral edema and GCS is <8, consult neurosurgery for ICP monitoring

Complications of DKA Thrombosis ARDS Dehydration, low flow state Avoid central lines if possible ARDS Rapid fluid resuscitation with low albumin at baseline  capillary leak, pulmonary edema Rare complication in pediatric DKA

Complications of DKA Hyperchloremic metabolic acidosis Hypoglycemia May check urine for ketones if unsure whether DKA has resolved Hypoglycemia Rare with appropriate dextrose titration Hypokalemia Can lead to fatal arrhythmias K+ must be repleted aggressively

10 Tips for Managing DKA in PICU 2 large-bore PIVs Frequent lab monitoring Hourly neuro checks Watch for falling sodium Correct hypokalemia aggressively NEVER give bicarb Do NOT titrate insulin drip Mannitol to bedside Order IVF pre-PICU arrival Search for underlying cause (infection, non-compliance, etc.)