Vital capacity inhalation induction with sevoflurane: An alternative to standard intravenous induction for patients undergoing cardiac surgery

Objective: To determine the respiratory and cardiovascular effects of a hig h concentration vital capacity induction with sevoflurane compared with an intravenous induction with etomidate in patients scheduled for elective cor onary artery bypass graft (CABG) surgery. Design: Prospective, randomized, double-blind, controlled clinical trial. Setting: Cardiothoracic unit at a university hospital referral center. Participants:Twenty-two patients undergoing elective CABG surgery. Interventions: The study group (group S) received a vital capacity gaseous induction with sevoflurane 8% (n = 12) and the control group (group E) were given etomidate, 0.2 to 0.3 mg/kg (0 = 10). Anesthesia was supplemented wi th fentanyl, 8 mug/kg, and vecuronium, 0.1 mg/kg, in both groups. Measurements and Main Results: The speed of induction of anesthesia was com parable between the groups. There was a significant increase in minute vent ilation after induction of anesthesia in both groups. This increase was ass ociated with a small reduction in PaCO2. There were no clinically significa nt changes in pH and PaO2. The incidence of breath-holding and the need for an oropharyngeal airway were similar between the groups. Both groups had s imilar reductions in mean arterial pressure and cardiac output during the s tudy period; however, a downward trend in mean pulmonary artery pressure wa s noted in group S, whereas in group E it remained unchanged. Absolute plas ma epinephrine and norepinephrine values were low during the precardiopulmo nary bypass period in both groups. Conclusions: The technique of vital capacity inhalation induction with 8% s evoflurane offers a rapid onset of anesthesia, satisfactory airway control, and a good hemodynamic profile. Consideration should be given to the benef its of single-agent anesthesia and lowered pulmonary artery pressure during the precardiopulmonary bypass period. In addition to CABG surgery, this te chnique could be considered in patients with coronary artery disease underg oing noncardiac surgery, particularly for procedures in which spontaneous v entilation is preferred. Copyright (C) 2001 by W.B. Saunders Company.