The Cook-Swartz venous Doppler probe for the post-operative monitoring of free tissue transfers in the United Kingdom: a preliminary report

Accurate assessment of the perfusion of free tissue transfers has always been a challenge for surgeons undertaking microvascular reconstructive procedures. The complexities of flap microcirculation are often difficult to assess despite all the subjective and objective examination techniques available today, particularly when the free tissue transfer is buried, and not visible for monitoring. The Cook-Swartz venous Doppler system is a technique for monitoring venous flow in free tissue transfer consisting of an implantable, removable, 20 MHz ultrasonic probe around the venous pedicle and a battery operated portable monitor. We perceive it as a quick and easy to use system, which in our study was well received by both medical and nursing staff. It can be used in conjunction with other monitoring techniques and we found it of value following revascularisation, during inset and in post-operative monitoring of free flaps particularly when operating outside our base hospital. We believe our initial experiences, on 24 patients, with the device, supports the use of a Cook-Swartz probe as an adjunct to traditional clinical monitoring techniques. We have had no technical difficulties with its application, use and removal, so far and we plan to continue with its use when it becomes available outside of a clinical trial.