Diabetic ketoacidosis (DKA)
Concise ED‑facing guide covering recognition (including atypical/euglycaemic presentations), initial priorities and practical management principles. This is an emergency medicine overview - follow your local trust DKA protocol and involve the diabetes team and critical care early for definitive infusion orders and ongoing inpatient care (NICE NG17; NG3 for pregnancy).
Definition and diagnostic criteria
DKA = insulin deficiency ± increased counter‑regulatory hormones → hyperglycaemia, ketonaemia and metabolic acidosis.
Typical diagnostic features (one accepted ED set)
- Ketonaemia ≥ 3.0 mmol/L OR ketonuria (≥ 2+ on dipstick).
- Blood glucose
> 11 mmol/L OR known diabetes (note: glucose can be only mildly raised or near‑normal in euglycaemic DKA).
- Blood pH < 7.30 OR bicarbonate < 15 mmol/L.
If clinical suspicion is high (nausea, vomiting, abdominal pain, dyspnoea, malaise) check ketones and blood gas even when glucose is not markedly elevated (NICE NG17; MHRA).
Pathophysiology
- Insulin deficiency → reduced peripheral glucose uptake and increased hepatic glucose production; counter‑regulatory hormones (glucagon, catecholamines, cortisol, growth hormone) amplify hyperglycaemia.
- Osmotic diuresis → free water and electrolyte loss (Na+, K+) → dehydration, hypotension and risk of acute kidney injury.