RESUMEN
BACKGROUND: Prolonged extracorporeal circulation entails tremendous threats of red cell lysis, severe bleeding problems due to platelet injury and activation, and endothelial damages by sequestered leukocytes. In consideration of these problems, a new centrifugal pump was developed and tested clinically to evaluate its effectiveness. METHODS: We compared the effects of a centrifugal pump with those of a roller pump on hematological responses during cardiopulmonary bypass (CPB) in 20 coronary artery bypass surgery patients. The patients were divided into two groups of 10 each. The studied parameters included WBC counts, platelet counts, plasma Hb and D-dimer. Blood samples were taken after sternotomy, at 60 min, 120 min and 180 min after CPB start, and at 2 hr after CPB stop. RESULTS: No differences between the groups were found in bypass time, aortic cross clamp time, extracorporeal circulation flow and hematocrit. The centrifugal pump group demonstrated less platelet depletion (p<0.05), hemolysis (plasma Hb, p<0.05) and fibrinolysis (D-dimer, p<0.05). These differences were CPB time dependent and became statistically significant after 120 min bypass. CONCLUSION: We conclude that roller pump still can be safely used for standard cardiac procedures with bypass time less than 120 minutes and the centrifugal pump has significant potential to be safely applied to CPB for long ypass time in order to avoid postperfusion syndrome.