We evaluated the effects of smoking history and
albuterol treatment on the amplitude and frequency of
cough during emergence from
anesthesia. Before induction of
anesthesia, 68 patients were randomized to receive two puffs of a placebo or two puffs of
albuterol via a
metered dose inhaler.
Anesthesia was then induced with
thiopental,
fentanyl, and
succinylcholine. The patients' tracheas were intubated with an 8.0 mm-endotracheal tube, and
isoflurane administration was initiated. At the end of surgery,
isoflurane was discontinued, and the pressure in the endotracheal tube cuff was monitored via the pilot balloon while the end-tidal
isoflurane concentration was recorded. Of the 68 patients, 52 coughed before responding to command, but the incidence did not differ between smokers and nonsmokers (33 of 43 vs 19 of 25), nor did it differ between
albuterol-treated and untreated patients. There was no difference in the frequency or amplitude of
coughs between smokers and nonsmokers, nor did
albuterol affect either variable. The mean end-tidal concentration at which
cough first occurred was 0.30%+/-0.02%, and only 5% of patients coughed at values >0.6%. We conclude that 1)
cough is frequent during emergence; 2) smoking does not affect emergence
cough; 3)
albuterol treatment does not affect emergence
cough; and 4) patients are unlikely to
cough at end-tidal values of
isoflurane >0.6%.
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