The impact of a double vein anastomoses on doppler's loss of signal rates

Background: Impact on blood flow by double vein anastomosis in head and neck free flaps is unclear. We aimed to assess venous doppler loss of signal (LOS) rates of double vein system compared with a single vein system. Methods: Consecutive free flaps with implanted venous flow couplers between 2015–2017 were included. LOS rates were compared between groups and with regard to flap type, defect site and recipient vein within double vein group. Results: 92 double-vein (184 veins) and 48 single-vein flaps were included. LOS was similar in single- and double-vein flaps (11/48 (25%) versus 46/184 (25%), p = 0.765). Double veins had fewer flap takebacks compared with single vein (4.3% vs. 12.5%, p = 0.075). Common facial vein (CFV) anastomosis showed superior LOS rates compared with external jugular and CFV branches (p = 0.026). Conclusions: Double vein anastomosis does not impact LOS rates, results in fewer flap takebacks, yet LOS rates depend on selected recipient vein.