The effect of combined treatment with dextran 40 and acetylsalicylic acid on patency in severely traumatized small veins and arteries: an experimental study in the rabbit.

The effects of pharmacologic intervention on the fates of severely traumatized small veins and arteries have been studied in a rabbit model. Controls were given bolus doses of saline and a group treated with a combination of dextran 40 and acetylsalicylic acid starting prior to traumatization and continuing until postoperative day 5. Relative to controls, bleeding times in the treated group were significantly lengthened in arteries but not in veins, and venous patency significantly improved throughout the interval ending 2 weeks postoperatively. Arterial patency was at first highly improved but by 2 weeks, occlusion was virtually 100 percent. Since some of the occlusions took place more than a week after traumatization, the effects of antithrombotic agents on patency may need to be evaluated over considerably longer time periods than has previously been the rule.