Laser Doppler flowmetry is useful in the clinical management of small bowel transplantation

Objective-Laser Doppler flowmetry (LDF) has been used as a research tool to measure splanchnic perfusion. In this report, we aim to demonstrate the cl inical value of this technique in perioperative monitoring of transplanted small bowel. Methods-A 24 year old man underwent small bowel transplantation using a pre viously described technique. Microvascular blood flow in the transplanted b owel was measured using an LDF splanchnic probe. Postoperatively this was a pplied to the stoma facilitating direct measurements of graft mucosal flow. Measurements (perfusion units (PU)) were documented prior to implantation, post-reperfusion, postoperatively, during graft ischaemia, and in response to therapeutic interventions (dopexamine and phenylephrine infusions). Results-Prior to transplantation, biological zero was established. Flow at five, 15, and 60 minutes after reperfusion was 74 (1.9) PU, 87.5 (3.3) PU, and 141.5 (2.5) PU, respectively. Postoperative mucosal flow was 141.6 (2.9 ) PU. Subsequent LDF measurement detected absence of flow even though clini cal signs suggested only moderate reduction. This was confirmed on surgical re-exploration and facilitated prompt resection of a non-viable segment. F luid and dopexamine administration resulted in a dose dependent improvement in flow, independent of blood pressure. Addition of phenylephrine increase d total mucosal flow and unmasked a cyclical component. Conclusion-This case demonstrates the clinical value of LDF as an "alarm" t o indicate graft perfusion failure and as a monitor for therapeutic interve ntions. Phenylephrine and dopexamine may both be of value in improving muco sal flow in the transplanted small bowel.