Pediatric DKA Management
Diabetic ketoacidosis is the leading cause of diabetes-related death in children, and cerebral oedema is the dominant killer. The two highest-yield safety rules: never give a bolus of insulin and never correct osmolality faster than the protocol allows.
Biochemical diagnosis
All three required:
| Criterion | Threshold |
|---|---|
| Hyperglycaemia | Blood glucose > 11 mmol/L (~200 mg/dL) |
| Acidosis | Venous pH < 7.3 or bicarbonate < 18 mmol/L |
| Ketosis | Blood β-hydroxybutyrate ≥ 3 mmol/L (or moderate–large urine ketones) |
Severity by pH/bicarbonate: mild (pH < 7.3 / HCO₃ < 18), moderate (pH < 7.2 / HCO₃ < 10), severe (pH < 7.1 / HCO₃ < 5).
Fluids — start before insulin
| Step | Action |
|---|---|
| Initial resuscitation | 10 mL/kg 0.9% saline over 30–60 min; repeat only for shock (cap ~30 mL/kg before reassessing) |
| Deficit estimate | 5–7% (moderate) / 7–10% (severe) — do not over-estimate |
| Replacement | Deficit + maintenance, evenly over 48 h with isotonic fluid |
| Potassium | Add 40 mmol/L KCl once K⁺ < 5.5 mmol/L and urine output confirmed |
| Glucose | Add 5% (then 10%) dextrose once glucose < 14–17 mmol/L |
Use the maintenance fluid calculator for the Holliday–Segar maintenance component.
Insulin
- Start 1–2 hours after fluids begin, never before.
- Fixed-rate infusion 0.05–0.1 U/kg/hr of soluble insulin. Use the lower end (0.05) in younger children, lower pH risk groups, or established cases.
- No IV insulin bolus — it adds nothing and increases cerebral-oedema risk.
- Do not stop insulin to treat falling glucose; instead add/increase dextrose. Insulin clears ketones, not just glucose.
Corrected sodium — the cerebral-oedema canary
Hyperglycaemia dilutes measured sodium. A rising corrected sodium as glucose falls is reassuring; a falling corrected sodium signals free-water excess and rising cerebral-oedema risk. Track it each lab draw with the corrected sodium calculator.
Cerebral oedema — recognise and act fast
Higher risk: age < 5 years, new-onset diabetes, severe acidosis (pH < 7.1), low pCO₂, raised urea.
Warning signs: headache, recurrent vomiting, bradycardia, rising BP, irritability/drowsiness, falling GCS, cranial-nerve palsies, abnormal breathing.
Treat immediately — do not wait for imaging:
| Action | Detail |
|---|---|
| Hyperosmolar agent | Mannitol 0.5–1 g/kg over 10–15 min or 3% saline 2.5–5 mL/kg over 10–15 min |
| Reduce fluids | Cut IV fluid rate by ~⅓ |
| Airway/position | Nurse head midline, head of bed up; senior/ICU + neuro-imaging after stabilising |
Monitoring
Hourly neuro obs, glucose, fluid balance; 2-hourly electrolytes/blood gas/ketones early on. Aim to fall glucose no faster than ~5 mmol/L/hr and resolve ketosis (β-hydroxybutyrate < 1 mmol/L) before switching to subcutaneous insulin with an overlap.
Decision support for qualified clinicians only — verify against current primary guidelines and your clinical judgement.