Intraflap Vascular Catheterization Method for Monitoring, Prevention, and Intervention of Thrombogenesis in Free-Flap Surgery.

Background Thrombosis at the anastomotic site is a significant problem in free tissue transfer with microvascular anastomosis. We report a newly developed intraflap vascular catheterization (IFVC) technique for monitoring hemodynamics, prevention of thrombogenesis, and transcatheter intervention of free-flap thrombosis. Methods We performed a hospital-based, prospective study. Ninety-three patients underwent free tissue transfer by a single surgeon in a single hospital. In the IFVC group (n = 40), catheters were inserted into the arterial and venous branches of the flap main pedicle vessels near the anastomoses. The catheters were connected to the pressure monitor. A bolus injection of urokinase was administered every hour to the artery, and a continuous infusion of saline was initiated to the vein. The bolus injection of urokinase solution reached the arterial anastomosis by the retrograde flow. During the postoperative period, rapid injection of urokinase or saline was performed according to the pressure monitor. Intraflap vascular catheterization monitoring was performed postoperatively for 72 hours. Results The overall flap survival rate in the IFVC group was 100% (40 of 40), whereas the overall flap survival rate in the non-IFVC group was 96% (51 of 53). In a subgroup analysis of lower extremity reconstruction, the flap survival rate was 100% (22 of 22) with no cases of reanastomosis requiring a return to the operation room in the IFVC group. By contrast, the flap survival rate was 92% (22 of 24), with 6 cases of reanastomosis requiring a return to the operation room in the non-IFVC group (P = 0.04). Conclusions The IFVC method enables monitoring, prevention, and intervention of thrombi at anastomotic sites of the free flap. Intraflap vascular catheterization may increase free tissue transfer success rate, especially in high-risk cases, such as free-flap reconstruction after the lower extremity trauma or venous leg ulcer.