Does isoflurane optimize myocardial protection during cardiopulmonary bypass?

Area of Science:

• Cardiology
• Anesthesiology
• Cardiac Surgery

Background:

• Coronary artery bypass graft (CABG) surgery often involves aortic cross-clamping and cardioplegic arrest, posing risks to myocardial function.
• Myocardial protection strategies are crucial to minimize ischemia-reperfusion injury during these procedures.

Purpose of the Study:

• To evaluate the potential myocardial protective effects of isoflurane administered prior to aortic cross-clamping in patients undergoing CABG surgery.
• To assess isoflurane's impact on hemodynamic stability and cardiac function post-cardiopulmonary bypass.

Main Methods:

• A prospective, randomized study was conducted at a university medical center.
• Forty-nine patients undergoing elective CABG were divided into a control group (n=21) and an isoflurane group (n=28).
• Isoflurane was administered pre-cardiopulmonary bypass (CPB) in the intervention group.

Main Results:

• Patients receiving isoflurane showed a significantly higher cardiac index post-CPB compared to pre-CPB values, unlike the control group.
• The isoflurane group exhibited fewer ST-segment changes, indicating improved myocardial status.
• No significant difference in reperfusion arrhythmias was observed between the groups after aortic cross-clamp release.

Conclusions:

• Pre-aortic cross-clamp administration of isoflurane may enhance the myocardial protective efficacy of cardioplegia during CABG surgery.
• Isoflurane could be particularly beneficial in cases requiring extended aortic cross-clamping or when cardioplegia delivery is suboptimal.