Red Flags
- DKA: glucose >250, ketones positive, pH <7.3, HCO₃ <15 — ICU/HDU; isotonic crystalloid then half-saline; insulin infusion; potassium replacement once K+ <5.5[1]
- HHS: glucose >600, osmolality >320, minimal ketones — slow glucose correction (<3 mmol/L/h); cautious sodium replacement; thrombosis prophylaxis[1]
- Severe hyperkalaemia (K+ ≥6.5 with ECG changes) on RAAS blockade or SGLT2 — emergency potassium-lowering bundle; pause culprits[1]
- Severe hyponatraemia (Na+ <125 with confusion, seizures) — slow correction (≤8–10 mmol/L/24h); avoid central pontine myelinolysis[1]
First-line treatment
Interventions
- Sick-day rules[1]Continue insulin and metformin during illness unless dehydrated; pause SGLT2 inhibitor with vomiting or dehydration; check glucose more frequently; ketone testing if T1DM with glucose >250 OR T2DM on SGLT2 with symptoms
- DKA/HHS resolution criteria[1]DKA: pH ≥7.3, HCO₃ ≥15, anion gap ≤12. HHS: osmolality <315, mental status restored, eating. Transition to SC insulin with ≥1 hour overlap before stopping infusion
First-line drug therapy
| Drug | Class | Adult | Paediatric | Notes |
|---|---|---|---|---|
| 0.9% sodium chloride or balanced crystalloid (DKA initial)[1] | Isotonic crystalloid | 1 L over 1 hour, then 1 L over 2 h, then per response (typically 250–500 mL/h × 4 h, then 125–250 mL/h) | 10–20 mL/kg bolus, max 50 mL/kg in first 4 h | Switch to 0.45% saline once corrected sodium normalises and glucose drops; balanced crystalloid (Plasmalyte) reduces hyperchloraemic acidosis |
| IV insulin infusion (DKA/HHS)[1] | Continuous IV regular insulin | 0.1 U/kg/h (may start with 0.1 U/kg bolus); titrate to glucose fall of 50–75 mg/dL/hr; add dextrose to fluids when glucose <250 | 0.05–0.1 U/kg/h | Continue until ketones cleared, anion gap closed, and patient eating; transition to subcutaneous basal-bolus with overlap |
| Potassium replacement[1] | Electrolyte | Add 20–40 mEq KCl/L to maintenance fluids once K+ <5.5; hold insulin if K+ <3.3 until replaced | Per weight per paediatric DKA protocol | DKA insulin drives K+ into cells; pre-existing total-body K+ depletion despite normal serum value |
| Hypertonic saline (severe symptomatic hyponatraemia)[1] | Osmotic correction | 3% saline 100 mL bolus over 10 min, repeat to maximum 300 mL or 4–6 mmol/L Na+ rise; cap correction <10 mmol/L per 24 h | — | Symptomatic hyponatraemia (seizures, coma); specialist supervision; avoid overcorrection (osmotic demyelination risk) |
0.9% sodium chloride or balanced crystalloid (DKA initial)[1]
Isotonic crystalloid
- Adult
- 1 L over 1 hour, then 1 L over 2 h, then per response (typically 250–500 mL/h × 4 h, then 125–250 mL/h)
- Paediatric
- 10–20 mL/kg bolus, max 50 mL/kg in first 4 h
Switch to 0.45% saline once corrected sodium normalises and glucose drops; balanced crystalloid (Plasmalyte) reduces hyperchloraemic acidosis
IV insulin infusion (DKA/HHS)[1]
Continuous IV regular insulin
- Adult
- 0.1 U/kg/h (may start with 0.1 U/kg bolus); titrate to glucose fall of 50–75 mg/dL/hr; add dextrose to fluids when glucose <250
- Paediatric
- 0.05–0.1 U/kg/h
Continue until ketones cleared, anion gap closed, and patient eating; transition to subcutaneous basal-bolus with overlap
Potassium replacement[1]
Electrolyte
- Adult
- Add 20–40 mEq KCl/L to maintenance fluids once K+ <5.5; hold insulin if K+ <3.3 until replaced
- Paediatric
- Per weight per paediatric DKA protocol
DKA insulin drives K+ into cells; pre-existing total-body K+ depletion despite normal serum value
Hypertonic saline (severe symptomatic hyponatraemia)[1]
Osmotic correction
- Adult
- 3% saline 100 mL bolus over 10 min, repeat to maximum 300 mL or 4–6 mmol/L Na+ rise; cap correction <10 mmol/L per 24 h
- Paediatric
- —
Symptomatic hyponatraemia (seizures, coma); specialist supervision; avoid overcorrection (osmotic demyelination risk)
Safety-net
- If you are vomiting or have severe diarrhoea, pause SGLT2 inhibitor and contact your clinician same day — risk of euglycaemic DKA[1]
- Drink fluids freely during illness if able; if unable to keep fluids down, seek urgent care[1]
- Severe nausea, abdominal pain, breathlessness, or confusion — call emergency services (could be DKA or HHS)[1]
Referral criteria
- DKA, HHS, or severe hyperkalaemiaICU/HDU for IV insulin infusion, fluid resuscitation, electrolyte management[1]
- Severe hyponatraemia (Na+ <125) or hypernatraemia (Na+ >155)Hospital admission for cautious correction with monitoring[1]
- Recurrent DKA / HHS despite appropriate sick-day educationDiabetes specialist for adherence and regimen review[1]
Clinical summary
Peri-operative and acute-illness fluid and electrolyte management in adults with diabetes — DKA/HHS resuscitation, sick-day rules, dysnatraemia and hyperkalaemia.