Evaluation of clinical microvascular anastomoses--reasons for failure.

Thrombosis in clinical microvascular anastomoses is attributed to suture errors and utilization of severely damaged recipient arteries. Histopathological specimens from 24 microvascular anastomoses and 77 vessel biopsies from free tissue transfers and replantation cases were analyzed. Suture errors of any note were rare and occurred primarily in replantation cases in which team experience varied and fatigue was common. Recipient artery damage ranged from minimal to severe; clinical analysis confirmed the devastating effect of refractory spasm associated with intramural scarring from previous trauma. Additional studies by microvascular groups are needed to clarify the causes of thrombosis and the healing mechanism of microvascular anastomosis.