T. Miyashita et al., Preservation of collagen-induced whole blood platelet aggregation by tranexamic acid therapy in primary cardiac valve surgery, PERFUSION-U, 15(6), 2000, pp. 507-513
Haemostatic disorder is one of the most common complications following card
iac surgery with cardiopulmonary bypass (CPB). Tranexamic acid reduces bloo
d loss and allogeneic blood transfusion requirement in cardiac surgery. It
had been thought that tranexamic acid inhibited fibrinolysis alone followin
g CPB.
In the present study, the haemostatic effects of tranexamic acid (20 mg/kg
body weight bolus after induction of anaesthesia followed by continuous inf
usion at 2 mg/kg/h), including fibrinolysis and platelet function, were inv
estigated in 22 patients (tranexamic acid group n = 12; control group n = 1
0) undergoing prim-cry cardiac valve surgery.
Fibrinolysis following CPB was reduced significantly in the tranexamic acid
group. Following protamine administration, the reduction of collagen-induc
ed whole blood platelet aggregation was mitigated significantly in the tran
examic acid group compared with the control group (36% reduction in the tra
nexamic acid group vs 58% in the control group; p = 0.011). although platel
et counts did not differ between the two groups.
In conclusion, tranexamic acid not only inhibits fibrinolysis directly, but
also may preserve platelet function following CPB.