One hundred and two rat femoral vessels, both vein and artery, were transected and repaired with a standard technique. After a 30-minute observation period, vessel clamps were reapplied in a standardized manner. The repairs were reexplored at 2 weeks. The results demonstrated no serious reduction in vessel patency in the first period or at the 2 week exploration. Reapplication of vessel clamps after an initial flow period post anastomosis does not have a significant effect on vessel patency.