Platelet protection by aprotinin in cardiopulmonary bypass: Electron microscopic study

• Published in: The Annals of thoracic surgery Vol. 53; no. 3; pp. 477 - 481
• Main Authors: Lavee, Jacob, Savion, Naphtali, Smolinsky, Aram, Goor, Daniel A., Mohr, Rephael
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.03.1992; Elsevier Science
• Subjects: Adult; Aged; Aprotinin - pharmacology; Biological and medical sciences; Blood Loss, Surgical; Blood Platelets - drug effects; Blood Platelets - ultrastructure; Blood. Blood coagulation. Reticuloendothelial system; Cardiopulmonary Bypass; Female; Humans; Male; Medical sciences; Microscopy, Electron, Scanning; Middle Aged; Pharmacology. Drug treatments; Platelet Aggregation - drug effects; Platelet Count - drug effects; Heart; Human; Blood coagulation; Scanning electron microscopy; Enzyme; Proteinase; Enzyme inhibitor; Cardiovascular disease; Cardiopulmonary bypass; Pathology; Chemotherapy; Treatment; Hemostasis; Surgery; Platelet function; Anesthesia; Antifibrinolytic
• ISSN: 0003-4975; 1552-6259
• DOI: 10.1016/0003-4975(92)90272-6

To evaluate the functional integrity of platelets in patients administered the proteinase inhibitor aprotinin during cardiopulmonary bypass, 20 patients undergoing a complicated and prolonged open heart operation were studied. They were randomized to receive either a high dose of aprotinin (total dose, 6 to 7 × 10 6 KIU) before and during cardiopulmonary bypass (10 patients) or a placebo (10 patients). Blood samples were collected preoperatively, at the termination of bypass, and 90 minutes thereafter to assess platelet count and aggregation on extracellular matrix, which was studied by scanning electron microscopy. On a scale of 1 to 4, mean preoperative platelet aggregation grades were similar in both groups (3.5 ± 0.5). Postoperatively, at the termination of cardiopulmonary bypass and 90 minutes thereafter, all 10 patients treated with aprotinin revealed normal, unchanged platelet aggregation (grade, 3.5 ± 0.5), whereas all placebo-treated patients showed severely disturbed aggregation (grade, 1.4 ± 0.5) ( p < 0.001). The platelet count was similar in both groups before and after operation (preoperatively, 182 ± 75 × 10 9/L and 146 ± 30 × 10 9/L, and postoperatively, 87 ± 13 × 10 9/L and 80 ± 27 × 10 9/L for the aprotinin and placebo groups, respectively). Total 24-hour postoperative bleeding and blood requirement were significantly lower in the aprotinin group (371 ± 84 mL and 2 ± 0.7 units, respectively) compared with the placebo group (608 ± 28 mL and 3.4 ± 1.3 units, respectively) ( p < 0.01). These results demonstrate that improved postoperative hemnstatis is directly related to the complete preservation of platelet function achieved by the protective properties of aprotinin.