Metabolic emergencies - hypo- and hyperkalaemia
Description
- 98% of body potassium is intracellular - the plasma level is a poor guide to total body stores
- Normal 3.5-5.2 mmol/L
| Threshold | Severity | |
|---|---|---|
| Hyperkalaemia | >5.5 mild, >6.0 moderate, >6.5 severe | Or any level with ECG change - the ECG outranks the number |
| Hypokalaemia | <3.5 mild, 2.5-3.0 moderate, <2.5 severe |
- Pseudohyperkalaemia - always exclude before treating
- Haemolysed sample, fist clenching with tourniquet, delayed processing, marked thrombocytosis (>1000) or leucocytosis, sampling above a drip
- Clue: high K+ with a completely normal ECG and no cause. Repeat as a free-flowing or plasma (lithium heparin) sample
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