| ||||||||||||||
|
|
|||||||||||||
Department of Anesthesiology, University of Miami, Miami, Florida; Division of Anesthesiology, Cleveland Clinic Florida, Weston Florida
Address correspondence and reprint requests to Michael C. Lewis, MD, Department of Anesthesiology, Miller School of Medicine at the University of Miami, P.O. Box 016370 (R-370) Miami FL 33101. Address e-mail to mclewis{at}med.miami.edu.
Inhaled induction of anesthesia is occasionally used in adults. Using a modified vital capacity sevoflurane/nitrous oxide (N2O) inhaled induction, we evaluated the effect of increasing age on the onset time of anesthesia. Twenty patients, aged 26-65 yr, performed a vital capacity breath followed by regular tidal breathing from an anesthesia circuit primed with sevoflurane 8%/N2O/O2. The following values were recorded: time to loss of eyelash reflex (LOER); time to bispectral index
60 (BIS
60); expired fraction of sevoflurane at the time of induction, LOER and BIS
60. The mean times and 95% confidence intervals to LOER and BIS
60 were 54 s (37-70 s) and 175 s (143-207 s), respectively, and were significantly prolonged by aging (r = 0.65; P = 0.002). Times to LOER and BIS
60, predicted from the regression line, were 3.9 and 2 times longer in a 60-yr-old than in a 30-yr-old patient. The expired fraction of sevoflurane measured at time to LOER and BIS
60 decreases with increase in age. We conclude that inhaled induction with sevoflurane/N2O is dramatically prolonged with increased age.
This article has been cited by other articles:
![]() |
R. A. Audisio, A. P. Zbar, and M. T. Jaklitsch Surgical Management of Oncogeriatric Patients J. Clin. Oncol., May 10, 2007; 25(14): 1924 - 1929. [Abstract] [Full Text] [PDF] |
||||
|