SINGLE-BREATH VITAL CAPACITY RAPID INHALATION INDUCTION IN CHILDREN -8-PERCENT SERVOFLURANE VERSUS 5-PERCENT HALOTHANE

Background: The authors compared the speed of induction of anesthesia with sevoflurane with and without nitrous oxide with the speed of halo thane and nitrous oxide using a single-breath vital capacity induction . Methods: With informed parental consent, 51 healthy unpremedicated c hildren aged 5-12 yr were randomized to inhale a single breath of one of three gas mixtures: 8% sevoflurane in 66% nitrous oxide, 8% sevoflu rane in oxygen, or 5% halothane in 66% nitrous oxide. A blinded observ er recorded the times to loss of the eyelash reflex, return of conjuga te gaze, the presence of ah-way reflex responses, involuntary movement , and hemodynamic responses. Results: Forty-two children completed the study. The times (mean +/- SD) to loss of the eyelash reflex with sev oflurane/nitrous oxide, 38 +/- 8 s, and for sevoflurane-oxygen, 34 +/- 12 s, were less than that with halothane-nitrous oxide, 58 +/- 17 s ( P < 0.01), Movement occurred less frequently during sevoflurane than d uring halothane anesthesia (P < 0.05), The times to return of conjugat e gaze and the incidence of airway reflex responses were similar among the groups. The incidence of dysrhythmias in the sevoflurane groups w as less than that in the halothane group (P < 0.01). Conclusions: Indu ction of anesthesia with a single breath of 8% sevoflurane with or wit hout 66% nitrous oxide is more rapid than with 5% inspired halothane w ith 66% nitrous oxide in children. The incidence of movement and dysrh ythmias during a single-breath induction with sevoflurane are less tha n they are with halothane.