Failure of lidocaine to modify suxamethonium induced biochemical changes.

: Twenty patients were studied in a prospective double-blind randomized trial to determine the effects of intravenous lidocaine pretreatment on suxamethonium induced biochemical changes. Lidocaine 1 mg. kg-1 failed to attenuate changes in serum potassium, significantly decreased serum calcium, and prolonged duration of suxamethonium blockade. There were no significant changes in plasmacholinesterase activity or other biochemical parameters. It is concluded that pretreatment with 1 mg. kg-1 lidocaine failed to attenuate suxamethonium induced biochemical changes.