End-To-Side Venous Anastomosis in Head and Neck Free Flap Reconstruction: A Systematic Review and Meta-Analysis.

[PURPOSE] We performed a systematic review and meta-analysis to evaluate the outcomes of end-to-side (ETS) anastomosis to the internal jugular vein (IJV) in head and neck free flap reconstruction. Postoperative outcomes of ETS were compared to the conventional end-to-end (ETE) technique.

[METHODS] A comprehensive electronic search was performed on PubMed/MEDLINE, Scopus, and Google Scholar databases. Odds ratios (ORs) were calculated with their 95% confidence intervals (CIs) for each study comparing the two groups (ETS vs. ETE).

[RESULTS] A total of 9645 patients undergoing 9663 head and neck free flap reconstructions (ETS, N = 2618; ETE, N = 7045) were included from 45 studies. The ETS technique showed an overall free flap failure rate of 2.5% (95% CI: 1.9-3.2). The pooled venous thrombosis rate was 3.8% (95% CI: 2.5-5.8), while the reoperation rate was 5.6% (95% CI: 2.7-11.5). No significant difference was found for the free flap failure rate (OR = 1.35, 95% CI: 0.77-2.36), venous thrombosis rate (OR = 0.93, 95% CI: 0.48-1.82) and reoperation rate (OR = 0.83, 95% CI: 0.42-1.63) when comparing the two groups.

[CONCLUSION] This study demonstrates that ETS venous anastomoses offer excellent outcomes, with safety and efficacy comparable to ETE anastomoses. Both techniques can be successfully employed depending on individual patient anatomy and surgeon experience.