Inhaled fenoterol pretreatment attenuates airway resistance response to endotracheal intubation.
BACKGROUND
Endotracheal intubation may induce vagal mediated bronchoconstriction. As fenoterol possesses bronchodilation effects, we studied the efficacy of fenoterol pretreatment on the increased resistance of total respiratory system (Rrs) caused by reflex bronchoconstriction in endotracheal intubation.


METHODS
Fifty patients were randomly allocated into two groups; group A (n = 25) with fenoterol inhaled and group B (n = 25) with placebo inhaled 10 min before induction. Patients were induced with sodium thiopental and vecuronium and resistance was measured 2 and 5 min after intubation with a Bicore pulmonary function monitor. Suctioning of the airway was performed 1 min before each measurement. Patients were further categorized into four conditions by smoking history and the presence of sputum in the suctionings. Condition I included patients that were smokers with no sputum collected. Condition II had non-smokers with no sputum collected. Condition III had patients with sputum collected but with no smoking history and condition IV were patients who had sputum collected and had a smoking history.


RESULTS
Patient who received fenoterol have significant lower total respiratory after intubation than those receiving placebo. There were no significant differences in post-intubation Rrs between smokers and non-smokers. Patients with sputum had the highest resistance after intubation with the placebo group. Heart rate and blood pressure were augmented in both groups.


CONCLUSIONS
Fenoterol pretreatment produced lower post-intubation Rrs after intubation when compared with the placebo group suggesting of a protective effect in vagal mediated bronchoconstriction.
Wu
R S
RS
Department of Anesthesiology, Chang-Gung Memorial Hospital, Lin-Kou Medical Center, Kweishan, Taoyuan, R.O.C.
Wu
K C
KC
Tsai
Y H
YH
Cheng
R K
RK
Tan
P P
PP
D000280:Administration, Inhalation; D000328:Adult; D000368:Aged; D000403:Airway Resistance / Q000187:drug effects*; D001794:Blood Pressure / Q000187:drug effects; D005280:Fenoterol / Q000494:pharmacology*; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007442:Intubation, Intratracheal; D008875:Middle Aged
D005280:Fenoterol