Laser Doppler surveillance of the circulation of free flaps and replanted digits.

In a series of 40 clinical free flaps and replantations the laser doppler technique has been used successfully for postoperative surveillance of circulation. A uniform flow pattern was obtained from all uncomplicated cases contrasting to the flow pattern seen in cases with thrombotic complication. The laser doppler continuously records flow of the microcirculation and is able to monitor blood flow in all types of free tissue transfer presently used as well as replantations. The laser doppler has effectively diagnosed two arterial thromboses with a characteristic flow pattern. It can distinguish venous from arterial occlusion. It can record flow in skin flaps which are difficult to judge clinically and in buried flaps, where no clinical observations are possible. The laser doppler should be used in conjunction with routine clinical observations.