Feasibility of Anesthesia Maintenance With Sevoﬂurane During Cardiopulmonary Bypass: A Pilot Pharmacokinetics Study Roberta Meroni, MD, Stefano Gianni, MD, Marcello Guarnieri, MD, Francesco Saglietti, MD, Marco Gemma, MD, Alberto Zangrillo, MD, Elena Bignami, MD 1 Department of Anesthesia and Intensive Care, IRCCS San Raffaele Scientiﬁc Institute, Milan, Italy Objective: Adequate maintenance of hypnosis during anesthesia throughout surgery using sevoﬂurane alone was investigated. In addition, sevoﬂurane pharmacokinetics during cardiopulmonary bypass were analyzed. Design: This was a pilot pharmacokinetic study. Setting: Tertiary care university hospital. Participants: The study comprised 10 patients aged between 18 and 75 years who underwent elective mitral valve surgery. Interventions: The end-tidal and sevoﬂurane plasma concentrations were measured throughout cardiac surgery procedures involving cardiopulmonary bypass. The sevoﬂurane plasma concentration was measured using gas chromatography. In addition, the ratio between sevoﬂurane alveolar concentration and inspired concentration over time (F A /F I ) was analyzed to describe wash-in and wash-out curves. Measurements and Main Results: Hypnosis was maintained adequately throughout surgery using sevoﬂurane alone. The bispectral index was maintained between 40 and 60 during cardiopulmonary bypass. The end-tidal sevoﬂurane was signiﬁcantly different before and during cardiopulmonary bypass (1.86% 70.54% v 1.30% 70.58%, respectively; p o0.001). However, the sevoﬂurane plasma concentration was not signiﬁcantly different before and after cardiopulmonary bypass start-up (40.55 mg/mL [76.62-125.33] before cardiopulmonary bypass and 36.24 mg/mL [56.49-81-42] during cardiopulmonary bypass). This mismatch possibly can be explained by changes that occured after cardiopulmonary bypass start-up, such as reductions of body temperature (36.331C 70.461C v 32.981C 72.381C, respectively; p o0.001) and hematocrit (35.62% 73.98% v 25.5% 73.08%, respectively; p o0.001). The sevoﬂurane alveolar concentration varied according to sevoﬂurane plasma concentration and bispectral index values. No adverse events regarding sevoﬂurane administration during cardiopulmonary bypass were observed. Conclusions: Sevoﬂurane end-tidal values were reliable indicators of adequate anesthesia during all cardiac surgery procedures involving cardiopulmonary bypass. & 2017 Elsevier Inc. All rights reserved. Key Words: sevoﬂurane; kinetics; bispectral index; cardiopulmonary bypass; anesthesia EVERY YEAR, MORE than 1 million patients undergo cardiac surgery. 1 Despite improvements in perioperative management, morbidity and mortality still are commonplace. Several randomized controlled trials (RCTs) and meta- analyses suggested that volatile anesthetic use in cardiac surgery (in particular sevoﬂurane and desﬂurane), mimicking ischemic preconditioning, might reduce perioperative myocar- dial damage and postoperative mortality. 2–13 Some authors 14 suggested that volatile anesthetic adminis- tration throughout surgery appeared to provide superior protective effects compared with administration only before Contents lists available at ScienceDirect journal homepage: www.jcvaonline.com http://dx.doi.org/10.1053/j.jvca.2016.12.018 1053-0770/& 2017 Elsevier Inc. All rights reserved. 1 Address reprint requests to Elena Bignami, MD, Department of Anesthesia and Intensive Care, IRCCS San Raffaele Scientiﬁc Institute, Via Olgettina 60, 20132 Milan, Italy. E-mail address: bignami.elena@hsr.it (E. Bignami). Journal of Cardiothoracic and Vascular Anesthesia 31 (2017) 1210–1217