Defining an Algorithm to Guide Salvage of a Failing Free Flap in Head and Neck Reconstruction

Introduction: Loss of a free flap for head and neck reconstruction can be fatal and devastating, however, the risk factors and techniques for salvaging a failing head and neck flap are poorly described.

Methods: Retrospective review of all head and neck free flaps performed from 2000-2010.

Results: Overall, 2296 head and neck free flaps were performed with 151 flaps (6.6%) suffering microvascular complications.  Patient age (mean: 58.4 years) and BMI (mean: 26.6kg/m²) had no impact on flap survival, nor did comorbidities including diabetes, vascular disease, smoking, or prior radiation.  However, prior chemotherapy was significantly associated with loss of a free flap (OR: 2.58, CI: 1.21-5.48; p=0.013). Flap type (ALT/AMT: 61, fibula: 33, radial forearm: 24, ulnar forearm: 5, latissimus dorsi: 10, VRAM/TRAM: 7, jejunum: 2, other: 9) had no impact on flap salvage rates; however, muscle flaps had significantly lower salvage rates than fasciocutaneous or osteocutaneous flaps (p=0.002). Surgeon experience also did not affect salvage rates (p=0.88).  Vein grafts were used in 23 arterial anastomoses and 26 venous anastomoses and did not affect flap survival; however, venous anastomosis performed with a Coupler had significantly fewer flap complications compared to hand-sewn anastomoses (p=0.03).  While venous thromboses were the most common, supercharging a flap did not decrease flap loss rates (p=0.45).  Flaps that were found to have an arterial and venous thrombosis had significantly lower salvage rates compared to complications with either the vein (n=59) or the artery (n=26; p<0.0001).  The use of aspirin, Fogarty catheter thrombectomy, thrombolytics, and heparin did not improve salvage rates.  Flaps requiring multiple takebacks (one takeback: 55.6% vs. 2 takebacks: 3.3% vs. 3 takebacks 1.3%; p=0.003) and late takebacks (>3 days) had significantly worse outcomes (p=0.003).  Overall successful salvage rate was 60.3% with 60 total flap losses (2.6%).

Conclusions: Microvascular complications in head and neck free flaps are relatively rare occurrences, and salvage techniques do not decrease flap loss rates.  While an attempt should be made to salvage a failing flap, multiple attempts are not recommended especially for muscle flaps. Thromboses of the artery and the vein and late thromboses also have an overall dismal prognosis for flap survival.