Does isoflurane optimize myocardial protection during cardiopulmonary bypass?
OBJECTIVE
To investigate the possible myocardial protective effect of isoflurane during aortic cross-clamp and cardioplegic cardiac arrest in patients undergoing conventional coronary artery bypass graft surgery.


METHODS
Prospective, randomized.


METHODS
University medical center.


METHODS
Forty-nine patients undergoing elective coronary artery bypass graft surgery divided into 2 groups: control group (n = 21) and isoflurane group (n = 28).


METHODS
Isoflurane was administered in the pre-cardiopulmonary bypass (CPB) period to the isoflurane group.


RESULTS
Hemodynamics and ST- segment variations were monitored in the pre-CPB period and after weaning from CPB in both groups. Incidence of reperfusion arrhythmias after release of aortic cross-clamp was compared. In the isoflurane group, the mean cardiac index after CPB was significantly higher than the pre-CPB value, whereas no difference between the 2 values was found in the control group. The higher cardiac index in the isoflurane group was associated with a lesser degree of ST- segment changes than in the control group. There was no significant difference between the 2 groups in the incidence of reperfusion arrhythmias after release of aortic cross-clamp.


CONCLUSIONS
The present report suggests that administration of isoflurane before aortic cross-clamping in patients undergoing coronary artery bypass graft surgery may optimize the myocardial protective effect of cardioplegia. Isoflurane may be particularly advantageous whenever prolonged periods of aortic cross-clamping or inadequate delivery of cardioplegia is expected.
Haroun-Bizri
S
S
Anesthesiology Department, American University of Beirut Medical Center, Beirut, Lebanon.
Khoury
S S
SS
Chehab
I R
IR
Kassas
C M
CM
Baraka
A
A
D018685:Anesthetics, Inhalation / Q000494:pharmacology; D001145:Arrhythmias, Cardiac / Q000209:etiology; D002302:Cardiac Output / Q000187:drug effects; D002315:Cardiopulmonary Bypass; D002316:Cardiotonic Agents / Q000627:therapeutic use; D001026:Coronary Artery Bypass; D004562:Electrocardiography; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D019157:Ischemic Preconditioning, Myocardial; D007530:Isoflurane / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D015428:Myocardial Reperfusion Injury / Q000517:prevention & control*; D011183:Postoperative Complications; D011446:Prospective Studies
D018685:Anesthetics, Inhalation; D002316:Cardiotonic Agents; D007530:Isoflurane