A comparison of crystalloid and blood induction cardioplegia in low-risk patients undergoing coronary artery bypass grafting

Abstract

Objective: Improvements in the application of cardio protective methods in open-heart surgery have been associated with decreased operative mortality, lowered incidence of perioperative myocardial infarction and improved cardiac functions. Material and Methods: One hundred consecutive patients undergoing their first elective coronary artery bypass grafting were prospectively randomized to receive either cold crystalloid cardioplegia (Group A, n: 50) or cold blood cardioplegia (Group B, n: 50). Patients in group A received initial cold crystalloid cardioplegia, patients in group B received initial cold blood cardioplegia that was a mixture (4:1) of the oxygenated blood of the patient and hyperkalemic crystalloid concentration. In both groups, following the inital cardioplegia, cold blood cardioplegia every 20 minutes and finally warm blood cardioplegia (370C) was performed before the removal of the aortic cross clamp. Results: In both groups, the baseline patient characteristics did not differ. During the cardiopulmonary bypass, blood transfusion was applied to the bypass circuit 11 patients in group A and 2 patients in group B because of low hemoglobin level (p<0.001). Following removal of the aortic cross clamp, the incidence of spontaneous defibrillation in group A was lower than in group B (p<0.001). Creatin kinase isoenzyme MB level at the 12th hour postoperatively was significantly higher in group A than in group B (p<0.01). Perioperative Ml was in three patients in group A and 1 patient in group B, (p: not significant). The incidence of atrial fibrillation, ventricular extrasystole and low cardiac out-put was similar in both groups. Conclusion: Cold blood induction performs better myocardial protection and faster myocardial recovery than the cold crystalloid induction cardioplegia in low-risk patients undergoing coronary artery bypass grafting.