Platelet protection by low-dose aprotinin in cardiopulmonary bypass: electron microscopic study.
To evaluate the effect of low-dose aprotinin during cardiopulmonary bypass on platelet function and clinical hemostasis, 30 patients undergoing various cardiopulmonary bypass procedures employing bubble oxygenators were randomized to receive either low-dose aprotinin (2 x 10(6) KIU in the cardiopulmonary bypass priming solution, 15 patients [group A]) or placebo (15 patients [group B]). Blood samples were collected before and after cardiopulmonary bypass to assess platelet count and aggregation on extracellular matrix, which was studied by a scanning electron microscope. On a scale of 1 to 4 preoperative mean platelet aggregation grades were similar in both groups (3.8 +/- 0.5 and 3.5 +/- 0.5 for groups A and B, respectively). Postoperatively, platelet aggregation on extracellular matrix decreased slightly in group A (2.8 +/- 1.3; p < 0.01) and significantly in group B (1.3 +/- 0.5; p < 0.001). Eleven of the 15 patients in group A remained in aggregation grade 3 or 4 compared with none of the group B patients. Platelet count was similar in both groups preoperatively and postoperatively. Total 24-hour postoperative bleeding and blood requirement were lower in the aprotinin group (487 +/- 121 mL and 2.3 +/- 1.0 units) than in the placebo group (752 +/- 404 mL and 6.8 +/- 5.1 units; p < 0.01). These results show that the use of low-dose aprotinin during cardiopulmonary bypass provides improved postoperative hemostasis, which might be related to the protection of the platelet aggregating capacity.
Lavee
J
J
Department of Cardiac Surgery, Maurice and Gabriela Goldschleger Eye Institute, Tel Hashomer, Israel.
Raviv
Z
Z
Smolinsky
A
A
Savion
N
N
Varon
D
D
Goor
D A
DA
Mohr
R
R
D000368:Aged; D007611:Aprotinin / Q000008:administration & dosage*; D001792:Blood Platelets / Q000187:drug effects* / Q000473:pathology; D001803:Blood Transfusion; D002315:Cardiopulmonary Bypass; D001026:Coronary Artery Bypass; D003327:Coronary Disease / Q000097:blood / Q000601:surgery*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006349:Heart Valve Diseases / Q000097:blood / Q000601:surgery*; D006350:Heart Valve Prosthesis; D006488:Hemostasis, Surgical; D006801:Humans; D008297:Male; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D015539:Platelet Activation / Q000187:drug effects / Q000502:physiology; D010973:Platelet Adhesiveness / Q000187:drug effects / Q000502:physiology; D010974:Platelet Aggregation / Q000187:drug effects / Q000502:physiology; D010979:Platelet Function Tests; D011292:Premedication
D007611:Aprotinin