Plasmapheresis Techniques During Cardiac Surgery

Plasmapheresis is an aggressive autologous blood conservation method utilized in cardiac surgery to reduce patient exposure to homologous blood transfusion. Presently the three perioperative techniques which have been used clinically incorporate varying methodology in producing platelet rich plasma (PRP). However, no prospective randomized study has been made to concurrently examine the benefits of individual devices. Fifty-two consenting adult cardiac patients who met selection criteria were randomly assigned to one of three plasmapheresis devices: Plasma Saver (PS), Cell Saver (CS), and Autotrans 1000 (AT 1000). Following induction of anesthesia, 20% of each patient's estimated plasma volume was removed, stored and then reinfused following the reversal of heparin with protamine. One hundred and twenty-two parameters were measured for each patient. These included anthropomorphic, operative, cardiopulmonary bypass, and postoperative follow-up parameters. Indices of hemostasis were measured which included coagulation screens and thrombelastographic data. There were no differences between groups in all preoperative parameters including the volume of PRP removed. Fibrinogen levels in the PRP were 213.9 +/- 63, 219.4+/-73, and 188.9+/- 69mg/dl in groups PS,CS, and AT 1000 (p=NS), while platelet counts were 178.4 +/- 73, 121.6 +/- 85, and 210.6 +/- 77 109/L, respectively (p<.05 CS vs. AT). There were no differences in chest tube drainage, time on ventilator, or length of ICU stay between groups. However, patients in PS group had significantly lower discharge platelet counts than groups CS and AT 1000. Total homologous blood exposure rate (donor blood exposure per patient) was 8.2 units in group PS, 4.5 in CS, and 5.4 in AT 1000, (p=NS). The currently available techniques for perioperative PRP production differ in both methodology and platelet yield, although the difference did not result in significantly different patient postoperative outcome indices.