Effect of smoking on induction of anaesthesia with sevoflurane

Inhalational induction with sevoflurane has been shown to be a viable alter native to intravenous induction; however, studies have focused mainly on he althy patients or volunteers. Airway complications ill patients with potent ial airway irritability have not been studied. Sixty smokers undergoing gen eral anaesthesia were randomly assigned to one of three groups: group 1, vi tal capacity breathing with 8% sevoflurane; group 2, tidal breathing with 8 % sevoflurane; and group 3, tidal breathing with step-up of sevoflurane (se voflurane concentration increased by increments of 2% every 10 s until 8%). Step-up induction was significantly slower to induce loss of consciousness than a vital capacity breath or tidal breathing at 8% (p < 0.05). Step-up induction produced more complications than tidal breathing at 8% (p = 0.05) . All patients had acceptable induction of anaesthesia with no patient havi ng an oxygen saturation below 96% at any time. Blood pressure and heart rat e decreased gradually over time in all groups (p < 0.001), but there were n o significant differences between groups. Patient satisfaction with the tec hniques was high with 59 of 60 patients willing to have the same technique again. Inhalational induction with sevoflurane can be used safely as an ind uction technique in smokers. In common with other patient groups, use of a high initial concentration reduces induction time without causing additiona l airway or cardiovascular complications.