Cerebral oedema is the leading cause of death: headache, irritability, falling heart rate, rising BP, falling GCS during treatment. Give hypertonic saline or mannitol, slow fluids, elevate the head, and call PICU.
Diagnosis and severity
- Hyperglycaemia (usually over 11), ketones, and acidosis (pH under 7.3 or bicarbonate under 18)
- Mild: pH under 7.3; moderate: under 7.2; severe: under 7.1
- Use actual or recent weight; cap deficit calculations at 10%
Deficit by severity (BSPED)
- Mild to moderate (pH 7.1 or above): assume 5% deficit
- Severe (pH under 7.1): assume 10% deficit
- Only give a 10 mL/kg bolus if shocked, then reassess
- Fluid deficit is replaced evenly over 48 h plus maintenance
Mild (pH 7.2 to 7.29)
- 5% fluid deficit
- Oral if tolerating, or IV
- Insulin 1 to 2 h after fluids
Moderate (pH 7.1 to 7.19)
- 7% deficit
- Insulin 0.05 to 0.1 units/kg/h
- Hourly glucose and neuro observations
Severe (pH under 7.1)
- 10% deficit, shock risk
- Watch for cerebral oedema
- Senior, HDU or PICU
Paediatric DKA
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1. Fluids
Replace the deficit evenly over 48 h plus maintenance. Boluses only for shock (10 mL/kg, do not subtract non-shock boluses from the deficit).
Replace the deficit evenly over 48 h plus maintenance. Boluses only for shock (10 mL/kg, do not subtract non-shock boluses from the deficit).
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2. Insulin
Start fixed-rate insulin (0.05 to 0.1 units/kg/h) 1 to 2 hours after fluids begin. Do not give an insulin bolus. Continue any long-acting insulin.
Start fixed-rate insulin (0.05 to 0.1 units/kg/h) 1 to 2 hours after fluids begin. Do not give an insulin bolus. Continue any long-acting insulin.
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3. Potassium and glucose
Add potassium once not anuric. Add 10% glucose to fluids when glucose falls below about 14 mmol/L.
Add potassium once not anuric. Add 10% glucose to fluids when glucose falls below about 14 mmol/L.
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4. Monitor
Hourly neuro observations, glucose and fluid balance; electrolytes and blood gas regularly. Watch for cerebral oedema and hypokalaemia.
Hourly neuro observations, glucose and fluid balance; electrolytes and blood gas regularly. Watch for cerebral oedema and hypokalaemia.
Cerebral oedema red flags
- Headache, agitation or irritability
- Falling heart rate and rising blood pressure
- Falling conscious level, abnormal posturing, pupil changes
Pitfalls
- Over-aggressive fluids or repeated boluses
- Giving an insulin bolus or starting insulin too early
- Not adding glucose as the sugar falls
- Missing hypokalaemia
MedPrep - www.medprep.uk - Educational revision aid only. Not clinical guidance. Doses are adult examples; check the BNF, current guidelines and local policy, and seek senior advice. Nov 2026