Optimal Timing for Secondary Reconstruction of Head and Neck Defects after Free Flap Failure.

BACKGROUND: Finite options exist to address free flap failure. There is a lack of consensus on the gold standard for secondary reconstruction in such cases. Herein, we determined the survival rate of a second flap following a total loss of an initial free flap during head and neck reconstructions and evaluated if there was a difference in the rate of secondary flap necrosis depending on the timing of reconstruction salvage. METHODS: We retrospectively reviewed 1572 free flaps for head and neck reconstruction from 2010-2022. Patients who underwent secondary surgery with flaps after failure of primary free flap were included. Patients were divided into three groups based on the time for secondary flap reconstruction from the time of primary reconstruction (Group A, 0-5 days; Group B, 6-30 days; Group C, >30 days). RESULTS: We identified 64 cases of complete flap loss after primary reconstruction requiring secondary reconstruction. Pedicled flaps were used in 34.4% of the cases, while a second free flap was used in 65.6% of the cases. Overall, the flap failure rate for secondary reconstructions was 6.7% in Group A, 35.3% in Group B, and 6.7% in Group C (p=0.022). For free tissue transfer, the success rate of a secondary reconstruction was 92.3% in Group A, 28.57% in Group B, and 93.3% in Group C. CONCLUSION: We favor an early microsurgical reconstruction (≤5 days) following primary reconstruction in cases of free flap failure. If early reconstruction cannot be performed, a deferred reconstruction with free tissue transfer (>30 days) should be considered.