Techniques of monitoring buried fasciocutaneous free flaps

BACKGROUND: Although postoperative monitoring of microsurgical reconstruction is key to discovering early vascular compromise, monitoring a buried flap can be problematic. METHODS: A single surgeon's tracheal and pharyngoesophageal reconstructions with fasciocutaneous free flaps performed between 2002 and 2007 are reviewed, and different monitoring techniques are described. RESULTS: Eighty-six cases of pharyngoesophageal and eight tracheal reconstructions were identified. The anterolateral thigh flap was used in 78 patients and the radial forearm flap was used in 16 patients. Three different monitoring techniques were used. In group I, a component of the flap used for neck resurfacing simultaneously served as a monitoring segment in 59 patients. No flap compromise or failure occurred. In group II, either an implantable or handheld Doppler device was used to monitor a completely buried flap in 29 patients. The implantable Doppler had a false-positive rate of 31 percent, leading to unnecessary surgical exploration. One case each of unrecognized flap loss occurred with the implantable and handheld Doppler methods. In group III, a segment of tissue separate from the main flap but sharing the same source vessels was temporarily externalized for monitoring and removed before patient discharge in six patients. This technique was also used in a patient with an anterolateral thigh flap for temporal reconstruction. There was no thrombosis or flap loss in these patients. CONCLUSIONS: Temporarily externalizing a segment of tissue is an easy and reliable method for monitoring a buried fasciocutaneous free flap. It is important, however, to avoid obstruction at the perforator level beyond the common source vessels.