Direct microvascular monitoring of a free autologous jejunal flap using microendoscopy: a case report

We used microendoscopic technique for microvascular monitoring of free autologous jejunal flap by the direct visualisation of the flow of erythrocytes through the capillary vasculature on both the mucosal and serosal surfaces.Blood flow was seen to be pulsatile, with individual erythrocytes visible in the capillaries. The best view was obtained when the scope was focussed directly on the capillary rather than the graft surface. The view of the unstained mucosal surface was bland apart from the fine capillary loops which were seen to fill with each pulsatile event. The microendoscopic examination of the serosal surface revealed much larger calibre vessels with obvious blood flow.The microendoscopic monitoring technique is simple and safe with direct visualisation of blood flow. The technique may also be useful for the monitoring of other free bowel transplants.Tissue oxygenation and maintenance of microvascular blood flow in grafted tissues are crucial for flap viability. Early identification of flap failure is a precondition of flap salvage and therefore important for flap prognosis [1]. Although many technical developments of free flap monitoring have now reached clinical application, very few are considered to be reliable and non-invasive for early recognition of flap failure [2]. Therefore, reliable monitoring of free microvascular tissue flaps would be a valuable new tool for clinicians [3,4].Non-invasive monitoring techniques are procedures of little or no morbidity that may be repeated frequently to assess tissue viability. The ideal non-invasive technique would be safe, sensitive, reliable, reproducible, simple to use and inexpensive [5]. Furthermore, postoperative monitoring of the perfusion of a free flap used in head and neck reconstruction is vitally important in achieving a favourable outcome [6].Several techniques have now an established place in free flap monitoring, some of them being technically demanding (Microdialysis, pH-measurement, Green light p