Abstract
We studied the effects of intermittent tepid blood cardioplegia on patients with prolonged aortic cross-clamping. Forty patients undergoing coronary artery bypass grafting with cross-clamp time of greater than 120 minutes were studied. The patients were divided into two groups according to the cardioplegic solutions, cold (4°C) crystalloid cardioplegia (Cold) and tepid (30°C) blood cardioplegia (Tepid). Cardiac function, myocardial enzyme and clinical outcomes were compared between the groups. Mean aortic cross-clamp time were 150±10 minutes in the Cold group and 149±4 minutes in the Tepid group. Recovery rate of spontaneous rhythm after cross-clamp removal and postoperative left ventricular stroke work index were significantly greater in the Tepid group than those in the Cold group. Duration of ventilation and ICU stay were significantly shorter and total release of CK-MB, requirements of dopamine during 48 hours after the operation and the incidence of low-output syndrome were significantly less in the Tepid group. There were no early deaths in the Tepid group versus three early deaths in the Cold group. In conclusion, intermittent tepid blood cardioplegia provided superior postoperative cardiac function and clinical results to conventional cold crystalloid cardioplegia, thus the technique appears to be safe for patients requiring prolonged aortic cross-clamping.
