Grafting of the major veins: the value of anti-thrombotic drugs to maintain patency.

The value of anti-thrombotic drugs to maintain the patency of grafts into the central venous system is described. The infrarenal portion of the inferior vena cava in mongrel dogs was used as the test bed. Two autologous graft materials were used: first, the tissue reaction to implanted silicone rubber, and, secondly, free peritoneum. Phenylbutazone was the drug administered to inhibit the aggregation of platelets at the bloodgraft interface. The low patency rate of the control group of animals conformed with previous experimental studies. The patency of grafts in the phenylbutazone-treated animals (up to 92%) was predictable after studying the in vitro behaviour of their platelets preoperatively.