Preoperative testing for radial forearm free flaps to reduce donor site morbidity.

OBJECTIVE To compare the clinical Allen test, preoperative Doppler ultrasonography, and intraoperative surgical Allen test with postoperative clinical findings in reconstruction of complex head and neck defects using radial forearm free flaps. DESIGN, SETTING, AND PATIENTS Retrospective review of 143 consecutive patients who underwent radial forearm free flap reconstruction from January 1, 1992, through December 31, 2006, at Vanderbilt University Medical Center. RESULTS Flap survival rate was 96.4%. No patients experienced digital necrosis or other findings of acute ischemia. Two patients (1.9%) who had normal results of clinical and surgical Allen tests developed hand contracture and palmar nodule formation. Surgical Allen test findings were normal in all patients who underwent reconstruction. Eighty-two arms had documentation of clinical Allen testing and Doppler ultrasonography in the patients' medical records. Agreement between these measures was 92.7%. The clinical Allen test result was 100% sensitive and 75% specific in predicting an abnormal Doppler ultrasonographic finding. CONCLUSIONS The clinical Allen test is an appropriate preoperative evaluation before radial forearm free flap reconstruction. The addition of Doppler ultrasonography should be limited to patients with abnormal clinical Allen test results. The surgical Allen test provides reassurance but does not preclude the possibility of ischemic hand complications.