The effect of dextran 40 on patency following severe trauma in small arteries and veins.

Arteriotomy/intimectomy and venotomy/intimectomy were performed in the rabbit ear. Low molecular-weight dextran (dextran 40) was infused 2 h before reperfusion and on postoperative days 1, 3 and 5 using a standard clinical protocol. Bleeding-times at reperfusion were recorded and patencies determined at intervals up to 2 weeks. Rabbits given single preoperative bolus doses of saline were used as controls. Dextran significantly prolonged bleeding-times in arteries and significantly improved early patency in both types of vessel, but the enhancements disappear by one week. Dextran 40 infusion thus has little effect on long-term patency.