Recent progress in microvascular surgery has opened new clinical possibilities in tissue transplantation and replantation by direct anastomoses of vessels less than one mm in external diameter. However, a large obstacle still remains in microsurgery, that is, occlusion of the anastomosis site by thrombosis which is mainly composed of platelets. Many anticoagulants and topical vasodilatic agents such as heparin, aspirin, persantin, coumarin and magnesium sulfate have been used to solve this problem.
Heparin inhibits the conversion of prothrombin to thrombin and Factos Ⅴ,Ⅸ,--, Aspirin inhibits collagen-induced platelet aggregation whereas the primary action of persantin is to inhibit ADP-induced platelet aggregation and the release reaction of platelets. Currently, ticlopidine-HCI which is known to inhibit the platelet aggregation to ADP, collagen and epinephrine, is widely in use as an effective anticoagulant for the patients of atherosclerosis, hemodialysis, and subarachoid hemorrhage.
Animal study was carried out for the ticlopidine-HCI to investigate the possibility of this agent to be used as a choice of anticoagulant in microvascular surgery. One hundred and twenty rats were divided into 3 groups. Group A was the control group. Aspirin and persantin were given orally in group B. Ticlopidine-HCI was given orally in group C. A femoral artery in one inguinal region and one femoral vein in the other side were severed and then were anastomosed with 10-0 nylon. The wounds were closed with 4-0 black silk. The patency was confirmed grossly and microscopically at 20 minutes, 3 days, and 3 weeks after anastomoses. The patency rates were as follows:
1. At 20 minutes after anstomoses, patency rates of arteries and veins were 100% in all groups.
2. At 3 days after anastomoses, in the control group the patency rates of arteries and veins were 95% and 85% respectively. Group B (aspirin-persantin)were 100% and 90% each. Compared with these, the patency rates of group C (ticlopidine) were better, all of the arteries and veins were patent.
3. At 3 weeks after anastomoses, the patency rates of arteries were 90% and veins were 80% in the control group. Arteries were 95% and veins were 90% in group B, whereas arteries were 100% and veins were 95% in group. C.
Therefore, it is concluded that the ticlopidine can be used in microvasular surgery as an anticoagulant of choice.
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