DKA with severe hypokalaemia when the intensive care unit is full
A 22-year-old man with type 1 diabetes is brought to the emergency department with 2 days of vomiting, abdominal pain, and increasing drowsiness after he stopped his insulin because he could not afford it. He is dehydrated, has deep sighing respiration at 32 breaths/min, pulse 118/min, BP 98/60 mmHg, and capillary glucose 31 mmol/L. Venous blood gas shows pH 7.08, bicarbonate 8 mmol/L, and potassium 2.8 mmol/L; serum sodium is 132 mmol/L, creatinine 150 µmol/L, and blood ketones 5.2 mmol/L. The hospital has intravenous fluids, soluble insulin, potassium chloride, and hourly bedside glucose testing, but the intensive care unit is full and the medical ward has one nurse for 12 patients. The nearest tertiary centre with an ICU bed is 90 minutes away. The patient is alert enough to answer questions but cannot walk without support.
1. Outline your first two hours of management, including whether insulin should be started before potassium is replaced. Justify the sequence.
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This is diabetic ketoacidosis with severe hypokalaemia. The dangerous mistake would be to start an insulin infusion immediately: insulin drives potassium into cells and can precipitate a fatal arrhythmia when the serum potassium is already 2.8 mmol/L.
First two hours:
- Fluids: start 0.9% sodium chloride 1 L over the first hour, then reassess BP, pulse, urine output, and sodium. Use cautious rates if there is any concern about cardiac or renal function.
- Potassium first: replace potassium before insulin. Give 20–30 mmol/hour if cardiac monitoring is available; if not, give 10 mmol/hour peripherally and arrange a monitored setting. Recheck potassium within 1–2 hours.
- Insulin: start a soluble insulin infusion at about 0.1 units/kg/hour only once potassium is at least 3.3 mmol/L. Continue fluids and potassium replacement during insulin.
- Monitoring: hourly glucose, potassium, pulse, BP, respiratory rate, and neurological status; repeat venous blood gas after 2 hours. Add dextrose when glucose falls below about 14 mmol/L.
- Search for precipitant: infection, missed insulin, myocardial infarction, or pregnancy where relevant.
The sequence is fluids and potassium before insulin because the immediate lethal risk is hypokalaemic arrhythmia, not hyperglycaemia.
2. The ward cannot provide hourly monitoring overnight. What is the safest disposition, and what would make you keep him locally?
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The safest disposition is stabilise and transfer to a monitored bed, because DKA requires frequent potassium and glucose checks, and severe hypokalaemia can cause arrhythmia. The ward ratio of one nurse to 12 patients cannot reliably deliver hourly observations or react to a sudden deterioration.
Transfer should occur after initial fluid resuscitation and after potassium replacement has begun, not before. If the potassium is rising, the patient is haemodynamically stable, and the ambulance is available, transfer is appropriate. Keep him locally only if transfer would be more dangerous than the monitoring gap: for example, if he becomes hypotensive, has a seizure, develops pulmonary oedema, or has a cardiac arrhythmia during preparation. In that case, treat the complication first, call the receiving centre for advice, and transfer as soon as he is stable enough. The decision is a risk comparison between an unmonitored ward and a 90-minute transfer, not a simple question of bed availability.