This retrospective review of 405 free radial forearm flap transfers for head and neck reconstruction evaluated the effect of venous drainage system selection in the flap and recipient bed on postoperative venous thrombosis. The authors performed the transfers at a single institution over a 15 year period. In 210/405 cases, a single flap vein, either the cutaneous (cephalic) or the deep (venae comitans) was anastomosed to the neck drainage vein (internal or external jugular). In 195/405 cases, a dual drainage system was created by anastomosing either two veins of the superficial or deep system, or a vein from each of the two systems, to the neck veins. In dual anastomoses, the neck venous drainage was also to either branches of a single vein or to separate venous systems (internal and external). The authors looked at the rate of re-exploration for venous thrombosis in all of the above permutations. Single flap drainage systems had a rate of 10%. When dual veins were used, but from a single system, the thrombosis rate was equivalent (9.4%). When dual veins from separate flap systems were used, the deep and superficial, the rate of thrombosis was significantly lowered (9.4 verusus 0.6 %; p<0.05). There were no thromboses in cases where two separate flap drainage systems were anastomosed to two separate neck drainage systems (0/135).
The authors set out to analyze the effect of creating a "backup system" of venous drainage on venous thrombosis in a critical human flap model. Their results support what seems intuitively obvious, that two independent venous drainage systems should have less of a likelihood of catastrophic venous failure than one, non-redundant, system. Their results show that in a large series of patients, the positive effect was significant. Although the flaps were used for head and neck cancer reconstructions, the radial forearm flap is an important flap for coverage of the upper extremity as well.
Journal of Reconstructive Microsurgery 19: 371-376, 2003.