Sevoflurane versus isoflurane in patients undergoing valvular cardiac surgery.
OBJECTIVE
To determine if sevoflurane provides hemodynamic and recovery characteristics comparable to isoflurane in patients undergoing surgery for valvular heart disease.


METHODS
A prospective crossover, dose-response study using sevoflurane and isoflurane before the start of surgery, followed by randomization to sevoflurane or isoflurane for surgery with blinded assessment for recovery.


METHODS
Tertiary referral cardiac center.


METHODS
Twenty-seven patients scheduled for elective valve surgery. Surgery consisted of 18 aortic valve and 12 mitral valve replacements, of which 3 patients had 2 valves replaced; 1, tricuspid repair; and 8, coronary artery bypass procedures.


METHODS
A pulmonary artery catheter was used to obtain a complete hemodynamic profile during the dose-response study before surgery. Transesophageal echocardiography was used to confirm the diagnosis, and electrocardiography monitored for myocardial ischemia.


RESULTS
Both agents showed similar hemodynamic effects at 0.5 and 1.0 minimum alveolar concentration. There was a tendency to decreases in heart rate, blood pressure, and cardiac output, whereas filling pressures remained stable with each volatile agent. Electrocardiography did not detect ischemic changes. Times to eye opening and extubation were similar with both agents, with sevoflurane tending to be earlier than isoflurane.


CONCLUSIONS
Sevoflurane showed a tendency to lower heart rates and cardiac index compared with isoflurane. Eye opening and extubation were slightly earlier. These findings were not statistically significant, however.
Bennett
S R
SR
Department of Anaesthesia, Castle Hill Hospital, Hull, England. sean@Remproad.freeserve.co.uk
Griffin
S C
SC
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018685:Anesthetics, Inhalation; D018592:Cross-Over Studies; D004305:Dose-Response Relationship, Drug; D004569:Electroencephalography; D005260:Female; D019918:Heart Valve Prosthesis Implantation; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007530:Isoflurane; D008297:Male; D008738:Methyl Ethers; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D011446:Prospective Studies; D011650:Pulmonary Alveoli / Q000378:metabolism; D000077149:Sevoflurane
D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D000077149:Sevoflurane; D007530:Isoflurane