[The prostacyclin-thromboxane system and platelet hemostasis following aortocoronary bypass with an uncomplicated postoperative course].

Prostacyclin-thromboxane system and platelet hemostasis have been studied in 56 patients upon aortocoronary bypass surgery with uncomplicated early postoperative period. It has been established that cardiopulmonary bypass surgery leads to a considerable increase in 6-keto-PGF1 alpha and TXB2 levels per platelet, as compared to preoperative values. By hour 18 postoperatively 6-keto-PGF1 alpha to platelet number ratio returns to baseline, while TXB2 to platelet number ratio remains higher than preoperative values, which determines a shift in 6-keto-PGF1 alpha to TXB2 ratio towards TXB2, thus ensuring, probably, enhanced platelet aggregation properties. Thrombocytopenia, a decrease in platelet aggregation properties and elevated blood plasma level of beta-thromboglobulin were observed upon aortocoronary bypass surgery. By hour 18 postoperatively the number of platelets increased significantly, their aggregation properties were enhanced, beta-thromboglobulin blood plasma level was reduced, however, the parameters under study did not reach normal values at that time. Increased levels of 6-keto-PGF1 alpha and TXB2 per platelet in the early postoperative period are considered an important component of compensatory-adaptive body reactions directed to normalization of the damaged body functions, namely hemostasis and microcirculation.