The deleterious effect of arteriovenous flow reversal during experimental free muscle transfer.

Arteriovenous flow reversal (AVR) has been used experimentally to salvage ischemic limbs and to create novel skin flaps with some success. The clinical applicability of AVR in muscle by way of two arteriovenous anastomoses in the rabbit was investigated. Twenty-four rabbits were divided into two groups. In Group 1 (control), the rectus femoris muscle was harvested and transplanted in the opposite thigh, anastomosing the donor femoral artery to the recipient femoral artery, and the donor rectus femoris vein to the recipient femoral vein. In Group 2 (flow reversal), the same procedure was done except the donor artery was anastomosed to the recipient vein and vice versa. Six and 24 hr postoperatively, specimens were compared macroscopically and by weight and histology. Reversed flow muscles were significantly heavier than control muscles at 6 hr and at 24 hr. Histologically, 6 hr of AVR caused edema, intramuscular hemorrhage, neutrophil infiltration, and thrombosis of most vessels. By 24 hr muscle cell degeneration was well advanced. All control muscles were viable, with only mild edema and slight peripheral necrosis. Possible reasons for the failure of AVR in muscle are discussed. On the basis of these results, AVR in free muscle transfer is not advocated.