Airway responses during desflurane versus sevoflurane administration via a laryngeal mask airway in smokers.

Cigarette smokers have a greater risk of respiratory complications during anesthesia compared with nonsmokers. It is not known whether the relative pungency of an inhaled anesthetic further contributes to the smokers' increased rate of such complications. In the present study, we tested whether the use of a more pungent anesthetic (desflurane) would result in a higher rate of coughing, breath holding, laryngospasm, or desaturation among patients who smoke. We randomly assigned 110 smokers to anesthesia with desflurane (n = 55) or sevoflurane (n = 55), administered via a laryngeal mask airway. Five patients (9%) receiving desflurane and nine patients (16%) receiving sevoflurane coughed (P = 0.39). Most coughing occurred during induction (33%) or emergence (56%), in the setting of airway manipulation and low anesthetic concentration. The rate of breath holding, laryngospasm, and desaturation was similar between those receiving desflurane versus sevoflurane. A retrospective comparison of this cohort of 110 smokers to a previous group consisting of 100 nonsmokers and 27 smokers receiving an identical anesthetic regimen indicates that cigarette smoking, but not choice of anesthetic, places patients at increased risk of respiratory complications.

Airway reflexes return more rapidly after desflurane anesthesia than after sevoflurane anesthesia.

Patients given a more soluble inhaled anesthetic usually take longer to awaken from anesthesia than do patients given a less soluble anesthetic. In the present study, we tested whether such a delay in awakening was also associated with a delay in restoration of protective airway reflexes. Patients were randomly assigned to receive desflurane (n = 31) or sevoflurane (n = 33) via a laryngeal mask airway. Demographics did not differ between groups. The average minimum alveolar anesthetic concentration fraction for both groups was 0.62, and the mean (+/-sd) minimum alveolar anesthetic concentration hours was 1.00 +/- 0.68 for desflurane versus 0.95 +/- 0.57 for sevoflurane, although more patients given sevoflurane also received regional anesthesia (17 for sevoflurane and 8 for desflurane). The time from stopping anesthetic administration to appropriate response to command was longer after sevoflurane (5.5 +/- 3.1 versus 3.4 +/- 1.9 min; P < 0.01). In addition, the time from first response to command to ability to swallow 20 mL of water without coughing or drooling was longer after sevoflurane. At 2 min after responding to command, all patients given desflurane were able to swallow without coughing or drooling, whereas 55% of patients given sevoflurane coughed and/or drooled (P < 0.001). At 6 min after responding to command, 18% of patients given sevoflurane still could not swallow without coughing or drooling (P < 0.05). We conclude that desflurane allows an earlier return of protective airway reflexes.