The relationship between venous occlusion time in island flaps and flap survivals

Island flaps were raised from the lower abdomen in rats, pedicled on the superficial epigastric vessels. The venous return was blocked by ligating the single draining vein. After various periods of occlusion, the venous continuity was restored by resecting the thrombosed portion of the vein and performing an end-to-end anastomosis. The results showed that if the venous occlusion time was 6 hours or less, the flaps survived. If the occlusion time exceeded 8 hours, all the flaps failed.