Effects of passive and active smoking on induction of anaesthesia.

It is said that cigarette smokers suffer stormy induction of anaesthesia; although plausible, this is unsubstantiated. We have studied the incidence of adverse events during induction, together with peripheral oxygen saturation (SpO2), in active and passive smokers, and in non-smokers. During induction, both active and passive smokers had a higher incidence of adverse events than non-smokers (P < 0.01 and P < 0.05, respectively). Irrespective of smoking status, those suffering adverse events had greater concentrations of carboxyhaemoglobin and suffered more oxygen desaturation than those not suffering such events. Although we were unable to demonstrate a direct link between smoking status and oxygen desaturation during induction, our study gives a firmer basis for exhorting patients not only to stop smoking before anaesthesia but also to avoid passive smoking.