One versus two venous anastomoses in microsurgical head and neck reconstruction: a cumulative meta-analysis.

Venous compromise is still the most common cause of free flap failure. The use of two venous anastomoses has been advocated to reduce venous compromise. However, the effectiveness of this approach remains controversial. A systematic review and cumulative meta-analysis was performed to assess the effect of one versus two venous anastomoses on venous compromise and free flap failure in head and neck microsurgical reconstruction. A total of 27 articles reporting 7389 flaps were included in this study. On comparison of one versus two venous anastomoses, the odds ratio (OR) for flap failure was 1.66 (95% confidence interval 1.11-2.50; P=0.014) and for venous compromise was 1.50 (95% confidence interval 1.10-2.05; P=0.011), suggesting a significant increase in the flap failure rate and venous compromise rate in the single venous anastomosis group. These results show that the execution of two venous anastomoses has significant effects on reducing the vascular compromise and free flap failure rate in head and neck reconstruction.