Published in:
Open Access
01-10-2016 | Reports of Original Investigations
Comparison of isoflurane and sevoflurane in cardiac surgery: a randomized non-inferiority comparative effectiveness trial
Authors:
Philip M. Jones, MD, Daniel Bainbridge, MD, Michael W. A. Chu, MD, Philip S. Fernandes, BA, Stephanie A. Fox, BA, Ivan Iglesias, MD, Bob Kiaii, MD, Ronit Lavi, MD, John M. Murkin, MD
Published in:
Canadian Journal of Anesthesia/Journal canadien d'anesthésie
|
Issue 10/2016
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Abstract
Purpose
Volatile anesthetics possess cardioprotective properties, but it is unknown if the cardioprotective effects extend equally to all members of the class. Although sevoflurane is a relatively newer anesthetic than isoflurane, its introduction into practice was not preceded by a head-to-head comparison with isoflurane in a trial focusing on clinically important outcomes. Our objective was to determine whether sevoflurane was non-inferior to isoflurane on a clinically important primary outcome in a heterogeneous group of adults undergoing cardiac surgery.
Methods
This was a pragmatic randomized non-inferiority comparative effectiveness clinical trial in 464 adults having coronary artery bypass graft and/or single valve surgery during November 2011 to March 2014. The intervention was maintenance of anesthesia with sevoflurane (n = 231) or isoflurane (n = 233) administered at a dose of 0.5-2.0 MAC throughout the entire operation. All caregivers were blinded except for the anesthesiologist and perfusionist. The primary outcome was a composite of intensive care unit (ICU) length of stay ≥ 48 hr and all-cause 30-day mortality. We hypothesized that sevoflurane would be non-inferior to isoflurane (non-inferiority margin < 10% based on an expected event rate of 25%). Secondary outcomes included prolonged ICU stay, 30- and 365-day all-cause mortality, inotrope or vasopressor usage, new-onset hemodialysis or atrial fibrillation, stroke, and readmission to the ICU.
Results
No losses to follow-up occurred. The primary outcome occurred in 25% of sevoflurane patients and 30% of isoflurane patients (absolute difference, −5.4%; one-sided 95% confidence interval, 1.4), thus non-inferiority was declared. Sevoflurane was not superior to isoflurane for the primary outcome (P = 0.21) or for any secondary outcomes.
Conclusion
Sevoflurane is non-inferior to isoflurane on a composite outcome of prolonged ICU stay and all-cause 30-day mortality. Sevoflurane is not superior to isoflurane on any other of the clinically important outcomes. This trial was registered at clinicaltrials.gov; NCT01477151.