The causes of early disorders of cerebral circulation in patients undergoing carotid endarterectomy.

Aim: to examine hemostasis in patients undergoing carotid endarterectomy as dependent on the course of the short-term postoperative period.

Materials And Methods: altogether 36 patients who had undergone unilateral carotid endarterectomy (CEAE) were examined. Intraoperatively, all the patients received unfractionated heparin (UFH) in a dose of 80 - 100 IU/kg bw. As dependent on the course of the short-term postoperative period the patients were distributed into two groups: group 1 included 12 patients who developed disorders of cerebral circulation (DCC) within the first hours after operation, group 2 included 24 persons with no complications. Plasma-platelet hemostasis, the system of natural anticoagulants and fibrinolysis were examined before, at the end, 6 hours and on the first day after CEAE.

Results: prior to operation all the patients had no significant change in the hemostatic system. Toward the end of operation groups 1 and 2 did not differ in the basic parameters of the hemostatic system. Group showed a remarkable platelet hyperaggregation. Six hours after operation group 1 demonstrated significantly lower values of ACT, BCT, MHO, an appreciably higher value of APTT and pronounced inhibition of fibrinolytic activity associated with platelet hyperaggregation. On the first postoperative day group 1 retained a significantly lower value of BCT, showed a significant lowering of APTT as compared to the previous observation stages and comparatively to group 2, demonstrated a significantly lower activity of AT III and fibrinolysis. At this stage ADO-induced platelet aggregation in group 1 was appreciably higher than in group 2. Platelet hyperaggregation in group 1 patients appeared a first manifestation of consumption coagulopathy. The significantly higher value of APTT mirrored a compensatory output of endogenous heparin. On the first postoperative day group 1 demonstrated a remarkable consumption of endogenous heparin, noticeably lower activity of AT III, material XIIaKDF inhibition, and retained pronounced platelet hyperaggregation.

Conclusion: the intensity and extent of the atherosclerotic process in the cerebral vessels together with platelet hyperaggregation lead to the rise of the thrombogenic potential and increase the risk of thrombogenic complications in the immediate hours following operation. Antiaggregation and anticoagulation therapy should be instituted in such patients in the preoperative period and resumed directly after operation.