Serum potassium following succinylcholine in patients with brain tumours.

Serum potassium levels were measured in 15 patients with brain tumours between 3-7 cm diameter, during thiopentone/70 per cent N2O in O2 anaesthesia, with mask ventilation controlled to maintain a constant end-tidal CO2 concentration. Potassium levels were determined one minute before and one and ten minutes after administration of succinylcholine 1.0 mg X kg-1 IV. No statistically significant increase in serum potassium occurred following succinylcholine, nor were there any ECG changes associated with succinylcholine administration. Use of succinylcholine in patients with brain tumours does not appear to cause elevation of serum potassium levels or ECG changes.