Factors associated with successful tracheal intubation of children with sevoflurane and no muscle relaxant.

UNLABELLED: Better definition of end points required to achieve successful tracheal intubation after induction with sevoflurane could improve patient care. The authors therefore designed a study that could determine, with meaningful confidence intervals, the time required to successfully intubate 80% of children by using 8% inspired sevoflurane and no muscle relaxant. We hypothesized that the time required could vary by age or body mass index. One-hundred fifty-three ASA physical status I or II patients received induction with 8% sevoflurane in 60% nitrous oxide with discontinuation of nitrous oxide 1 min after the start of the induction. The time until laryngoscopy remained close to the time required to achieve 80% successful intubation by varying induction time according to the success rate in each group of five patients. A probit model of induction time and age found that both were predictive of successful intubation (P values of 0.006 and 0.02, respectively). The induction times needed to achieve 80% successful intubation were 137 s (95% confidence interval, 94.6-159 s) and 187 s (153-230 s) for ages 1-4 yr and 4-8 yr, respectively. The persistence of spontaneous ventilation at the time of laryngoscopy, despite attempts to control ventilation, was associated with poor intubation conditions (P < 0.001). IMPLICATIONS: To successfully intubate 80% of children by using sevoflurane and no muscle relaxant, induction times of 137 and 187 s were needed in children of 1-4 yr and 4-8 yr, respectively.

Dynamic left ventricular outflow obstruction during lumbar laminectomy as an unexpected cause of intraoperative hypotension.

We present a case of previously undiagnosed hypertrophic obstructive cardiomyopathy (HOCM) with left ventricular outflow obstruction in a woman anesthetized for lumbar hemilaminectomy and diskectomy. The treatment of her sudden unexplained hypotension was initially confounded by a diagnosis of compensated congestive heart failure and diuretic therapy. Swift intervention with transesophageal echocardiography revealed the tru pathology altering her intraoperative treatment and her subsequent chronic treatment for her heart condition.