Synopsis
Confirm and risk-stratify raised potassium, stabilise cardiac membranes, shift potassium safely and secure definitive removal with rebound surveillance.
- UKKA defines hyperkalaemia from 5.5 mmol/L and recommends an urgent 12-lead ECG for every hospitalised adult with potassium at least 6.0 mmol/L.
- Use continuous three-lead monitoring at 6.5 mmol/L or above, with any hyperkalaemic ECG feature, or at 6.0–6.4 mmol/L when the patient is unwell or a rapid rise is expected.
- Repeat a potentially haemolysed or surprising sample promptly, but never delay treatment when the ECG, potassium and clinical context indicate genuine severe toxicity.
Key red flags
Peaked T waves, prolonged PR, flattened or absent P waves, widening QRS, bradycardia, sine wave or ventricular arrhythmia demands immediate calcium treatment.
Investigation priorities
Detect cardiac membrane toxicity and determine the immediate need for intravenous calcium.
Management branches
A laboratory or point-of-care result shows raised potassium or the ECG suggests hyperkalaemia.
- Use ABCDE, repeat potassium appropriately, obtain an urgent 12-lead ECG at 6.0 mmol/L or above and establish continuous monitoring for UKKA high-risk categories.
- Review renal output, acid–base state, glucose, medicines, cell injury and dialysis history while stopping exogenous potassium and avoidable causal agents.
Key medicines
Intravenous calcium salts for ECG toxicityUKKA recommends 30 mL calcium gluconate 10% over 10 minutes for non-arrest patients, or 10 mL calcium chloride 10% over 5 minutes in cardiac arrest or peri-arrest; reassess the ECG and repeat only through the algorithm.
Soluble insulin with glucoseGive 10 units soluble insulin with 25 g glucose under UKKA guidance; if pretreatment glucose is below 7 mmol/L, follow with 10% glucose at 50 mL/hour for five hours and titrate to the monitored glucose target.