Clinical study of normothermic cardiopulmonary bypass in 100 patients with coronary artery disease

During normothermic cardiopulmonary bypass (CPB), the body temperature is maintained at 37°C. Since 1987, it has been our standard practice to use normothermic CPB in our patients undergoing a cardiac operation, and our experience now consists of more than 3,000 consecutive patients. Myocardial protection is achieved through the combination of cold intermittent antegrade blood cardioplegia, no topical cooling, and a terminal ldhot shot” of blood cardioplegia. We disagree with the stance of the Toronto group that normothermic CPB requires the administration of large volumes of cardioplegic and crystalloid solutions and the frequent use of phenylephrine hydrochloride to ensure a low systemic vascular resistance. To establish a routine technique of cold heartwarm body bypass, we conducted a clinical study in 100 consecutive patients with coronary artery disease. We found that the total cardioplegia volume needed in our patients was 1,946 ± 257 mL, versus 4,700 ± 1,900 mL in the Toronto study, and an additional crystalloid volume loading of 400 ± 141 mL during CPB was needed in 26% of our patients, versus a total volume of 3,650 ± 800 mL in the Toronto series. Phenylephrine (250 μ) was used in 16% of our patients, versus 88% of the patients in the Toronto study (mean dose, 1.3 mg). During normothermic CPB, the mean radial arterial pressure was 57.3 ± 9.4 mm Hg. In our experience, normothermic CPB in combination with cold intermittent cardioplegia and a terminal hot shot has the following advantages: it facilitates the conduct of surgical procedures because it produces a clear operative field, it is easy for the perfusionist to manage, and it is associated with no adverse side effects.