Continuous Monitoring of Microvascular Anastomoses: An Observational Trial

This study is being done to see whether signals from a device that monitors blood flow through the free flap can be recorded and converted from an audible signal, like a heartbeat, into a visual signal. Researchers plan to use this information to ultimately help surgeons and care teams monitor free flaps to try to prevent flap failure.

Inclusion Criteria: * Scheduled for free flap surgery and planned to have an implanted doppler monitor * Arterial Doppler waveforms available for analysis * Able and willing to sign consent and return for clinical follow up * Age ≥ 18 years Exclusion Criteria: * Prior head and neck surgery within the region where surgeons plan to identify donor vessels ≤ 365 days prior to registration