[Comparison of epidural anesthesia and general anesthesia for patients with bronchial asthma]

We prospectively investigated the incidence of asthmatic attacks in 94 patients (1.5%) who were diagnosed as definite asthma. We separated the patients into three groups: epidural anesthesia (n = 10) including combined spinal/epidural anesthesia (n = 7), combined epidural and general anesthesia (n = 23), and general anesthesia (n = 54). General anesthesia was induced with propofol or midazolam and maintained with N2O and O2 with sevoflurane in adults. Patients who underwent epidural anesthesia and combined spinal and epidural anesthesia showed no asthmatic attacks. The incidence of bronchospasm with combined epidural and general anesthesia was 2/23. The incidence of bronchospasm with general anesthesia was 4/54. Bronchoconstriction occurred after tracheal intubation in 5 patients except in one patient, in whom it occurred after induction of anesthesia with midazolam. All episodes of bronchospasm in the operative period were treated successfully. The frequency of bronchospasm did not depend on the severity of asthmatic symptoms or the chronic use of bronchodilators before operation. These findings suggest that tracheal intubation, not the choice of anesthetic, plays an important role in the pathogenesis of bronchospasm.