Management of Diabetic Ketoacidosis in the PICU

1. Management of Diabetic Ketoacidosis in the PICU PICU Resident Lecture Series

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

3. 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

4. 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

5. 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

6. 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

7. 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

8. 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

9. 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

10. 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

11. 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

12. 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

13. 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

14. 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

15. 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

16. 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

17. 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

18. 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

19. Complications of DKA • Thrombosis • 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

20. Complications of DKA • Hyperchloremic metabolic acidosis • 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

21. 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.) 10 Tips for Managing DKA in PICU