Intravenous opioids reduce airway irritation during induction of anaesthesia with desflurane in adults

Desflurane is not used for the induction of anaesthesia despite its favoura ble pharmacokinetic characteristics because it causes airway irritation. We investigated whether pretreatment with i.v. narcotics reduced unwanted eff ects. One hundred and eighty adults were randomized to three groups (60 per group) to receive i.v. saline, fentanyl l mu g kg(-1) and morphine 0.1 mg kg(-1), respectively, before inhalational induction with desflurane in nitr ous oxide and oxygen. Mean time to loss of response to commands was 4.0 min , without significant differences between groups. The incidence of coughing was greater (25%) in the control group than in the fentanyl (5.0%) and mor phine groups (8.3%). The incidence of apnoea was 20.0% in the control group versus 13.3 and 5.0% in the fentanyl and morphine groups, respectively. La ryngospasm developed in 11.7% of controls compared with 3.3 and 1.7% in the fentanyl and morphine groups, respectively. More patients in the control g roup had excitatory movements (46.7%) than in the fentanyl (16.7%) and morp hine (8.3%) groups. These results demonstrate that i.v. opioids reduce airw ay irritability significantly during inhalational induction with desflurane in adults.