The effects of two different local anaesthetic solutions administered for oral surgery on plasma potassium levels in patients taking kaliuretic diuretics.

The effects of two different dental local anaesthetic solutions, administered for oral surgery, on the plasma potassium levels of patients taking non-potassium sparing diuretics has been investigated. There was a significant reduction in plasma potassium concentration in eight subjects who received 4.4 ml of 2% lignocaine with 1:80,000 adrenaline; the mean reduction from baseline being 0.30 mmol.l-1 10 min following intraoral extravascular injection of the local anaesthetic. There was no significant difference from the pre-treatment plasma potassium concentration 10 min following similar injections of 3% prilocaine with 0.03 IU.ml-1 felypressin in 8 patients; the mean change in these subjects being -0.05 mmol.l-1. It is suggested that the use of adrenaline-free local anaesthetics would seem to be appropriate in patients receiving kaliuretic diuretics.