Clinical evaluation of laser Doppler blood flow measurements in free flaps

Adequate assessment of blood flow in free flaps with early detection of circulatory failure is an unresolved clinical problem. In 23 patients undergoing microvascular free tissue transfers, laser doppler blood flow measurements and clinical observations were made hourly for the first two postoperative days. There was 1 flap failure in 6 instances in which it was clinically necessary to intervene, by reexploration or draining a hematoma, to ensure the survival of the flap. It was hypothesized that the laser doppler measurements would predict future clinical events. However, it was found that although these measurements did correlate with clinical observations, they did not predict them and were actually less accurate in indicating the need for clinical intervention or the final outcome of the free flap procedure.