Inflammatory response and minimized cardiopulmonary bypass

Approaches are described for dealing with the massive systemic inflammatory response induced by cardiopulmonary bypass (CPB), which, if unchecked, inflicts end-organ damage culminating in significant postoperative morbidity and mortality. Clinical trials of pharmacological antioxidants, e.g. N-acetylcysteine, are described and the use of cardioplegia enriched with pyruvate, a physiological energy substrate and antioxidant, which exerts a host of anti-inflammatory effects in a swine CPB model, is shown to afford robust post-CPB recovery in patients undergoing coronary revascularization on-pump. The advantages of miniaturized extracorporeal CPB systems, which minimize blood contact with the extracorporeal circuit and limit priming volume, and thus hemodilution, are examined. The benefits include reductions in circulating proinflammatory cytokines and activated neutrophils, incidence of atrial fibrillation, and duration of postoperative hospitalization.