Late Free Flap Failure in Head and Neck Reconstruction: Unusual Etiology in Two Case Studies and Literature Review.

The development of modern microvascular surgical techniques has enabled the reliable transfer of free vascularized tissue. This allowed for predictable reconstruction outcomes with excellent surgical success rates. However, devastating consequences of partial or total flap failure and subsequent loss may occur. This usually occurs in the first 48-72 h post-operatively. It is rare for flaps to fail in the late post-operative period and it remains poorly understood why flaps fail after day seven. We presented two patients in whom flap failure occurred after the seventh post-operative day (POD). Complete flap failure occurred after POD 9 and 27 in our cases. During the postoperative period, there was no evidence of early occlusion or insult to the vascular integrity such as venous/arterial compression. The cause of late flap failure was due to thrombophlebitis secondary to infection from the tracheostomy-neck fistula. This assumption was supported by recurrent failure of anastomoses revision.