Medical emergency: hyperglycaemia (or known diabetes) plus metabolic acidosis and ketosis. Driven by absolute or relative insulin deficiency; typical in T1DM but can occur in T2DM (especially with SGLT2i).
⚠ Red flags
- pH <7.1 or bicarbonate <5 — severe DKA
- K⁺ <3.5 — replete BEFORE starting insulin
- GCS drop / cerebral oedema (especially children) — give mannitol or hypertonic saline
- Anuria, hypotension — escalate care
Diagnostic criteria
Clinical
- Polyuria, polydipsia, vomiting, abdominal pain
- Kussmaul respiration, ketotic breath, dehydration, drowsiness
Investigations
- Glucose >11 mmol/L (or known T1DM with any glucose)
- Capillary or blood ketones >3 mmol/L (or urine ketones 2+)
- Venous pH <7.3 OR bicarbonate <15 mmol/L
Scoring tools
- Severity stratification: pH <7.0, HCO₃⁻ <5, K⁺ <3.5, GCS <12 → severe DKA
Investigations
Essential
- Capillary blood glucose and ketones
- VBG (pH, bicarbonate, K⁺, lactate)
- U&E, creatinine, FBC, CRP
- Urinalysis + MSU
- ECG (K⁺ changes, ischaemia as precipitant)
Optional
- CXR if respiratory infection precipitant
- Blood/urine cultures if sepsis suspected
- Amylase / lipase if abdominal pain marked
- Troponin if chest pain or known IHD
Management
Acute
- Fluids: 0.9% NaCl 1 L over 1h, then 1 L over 2h, 2h, 4h, 4h, 6h (titrate to BP, age, comorbidities)
- Fixed-rate IV insulin infusion (FRIII) 0.1 units/kg/h — do NOT bolus
- Add 10% dextrose at 125 mL/h once glucose <14 mmol/L (continue insulin)
- Potassium replacement when serum K⁺ falls below 5.5 (do NOT add if anuric)
- Treat precipitant (sepsis, MI, missed insulin, new diagnosis)
- Resolution criteria: pH >7.3, ketones <0.6, bicarbonate >15
Long-term
- Transition to SC insulin when patient eating; overlap IV insulin by 30–60 min
- Diabetes specialist nurse review, sick-day rules education
- Identify and treat trigger; psychosocial support if recurrent DKA
Non-pharmacological
- Hourly capillary glucose; ketones every 1–2h
- Strict fluid balance; consider catheter if not passing urine
- DVT prophylaxis once stable
Pharmacological
| Drug | Dose | Notes |
|---|---|---|
| 0.9% NaCl | 1 L over 1h then per protocol | Resuscitation and rehydration. |
| Soluble insulin | 0.1 units/kg/h IV infusion | Fixed rate; continue basal long-acting insulin if patient on T1DM regimen. |
| 10% dextrose | 125 mL/h IV when glucose <14 mmol/L | Maintains insulin to clear ketones without hypoglycaemia. |
| KCl | 20–40 mmol/L added to fluid | When K⁺ 3.5–5.5. Withhold if K⁺ >5.5 or anuric. |
| Antibiotic | Per source | If infective precipitant identified. |
Monitoring
- Capillary glucose hourly until stable
- Capillary or blood ketones every 1–2h
- VBG and U&E every 2–4h
- Hourly fluid balance and neurological status
Referral criteria
- Severe DKA (pH <7.0, K⁺ <3.5, GCS <12) — HDU/ICU
- Pregnant patient with DKA — obstetrics + diabetes joint care
- Recurrent DKA — psychology and adherence support
Complications
- Cerebral oedema (especially paediatric)
- Hypokalaemia / hypoglycaemia from over-treatment
- ARDS, AKI
- Death in untreated severe DKA
Special populations
- Pregnancy
- Lower threshold to diagnose (euglycaemic DKA possible). Joint obstetric / diabetes management; CTG monitoring.
- Renal impairment
- Reduced fluid volume per protocol; avoid potassium overload; nephrology input.
- Hepatic impairment
- Watch for lactic acidosis component; metformin must be stopped.
- Elderly
- Slower fluid resuscitation to avoid pulmonary oedema; cardiac monitoring.
- Paediatric
- Use paediatric DKA protocol; cerebral oedema risk — gradual rehydration, monitor GCS closely.