Effects of intraoperative plasmapheresis on blood loss in cardiac surgery

Intraoperative platelet-rich plasmapheresis allows autotransfusion of fresh, undamaged platelets and clotting factors at the completion of the operation. To evaluate this technology, we randomly assigned 100 consecutive patients who were to undergo an elective coronary bypass procedure and had normal clotting studies into the experimental (plasmapheresis) or the control group. Characteristics of both groups were similar, including average age (61.4 years versus 61.3 yean [experimental versus control group]), sex (73% male versus 74% male), preoperative weight (80.9 kg versus 80.2 kg), preoperative red cell mass (1,989 mL versus 1,890 mL), perfusion time (102 minutes versus 106 minutes), and coagulation studies. Both internal mammary arteries were used in 68% of the patients. All patients had preoperative and postoperative blood volume determinations and complete clotting studies. Sixty-two variables related to bleeding were analyzed. Strict indications for transfusion were a hemoglobin level less than 7 g/100 mL in patients younger than 70 years and a hemoglobin level less than 8 g/100 mL in patients older than 70 years. The group receiving intraoperative plasmapheresis had a significant reduction in operative red cell mass loss (1,050 ± 43 mL versus 1,226 ± 61 mL; p = 0.021), a reduction in the average homologous transfusion (0.67 ± 0.15 unit versus 1.8 ± 0.25 units; p = 0.0002), and an increase in the percentage of patients not requiring blood transfusions (66% versus 32%; p = 0.001). This technique is useful in reducing postoperative blood loss and homologous transfusions.