EFFECT OF SMOKING ON DOSE REQUIREMENTS FOR VECURONIUM

We have compared the potency of vecuronium given to 12 smokers and 12 non-smokers during propofol-alfentanil-nitrous oxide anaesthesia. Afte r obtaining individual dose-response curves, bolus doses of vecuronium were given to maintain neuromuscular block at 90-98% for 60 min. Addu ctor pollicis EMG was used to monitor neuromuscular block. Mean ED(95) values were 61.38 mu g kg(-1) and 47.49 mu g kg(-1) for smokers and n on-smokers, respectively (P < 0.01). The dose of vecuronium to maintai n 90-98% neuromuscular block was 25% higher in smokers than in nonsmok ers (96.80 vs 72.11 mu g kg(-1) h(-1); P < 0.01). These data reflect t he effects of smoking on neuromuscular block induced by vecuronium. Th e effect may be at the receptor level, although possible increased met abolism of vecuronium in smokers cannot be excluded.