Early Detection of Gut Ischemia-Reperfusion Injury During Aortic Abdominal Aneurysmectomy: A Pilot, Observational Study

Objective: D-lactate is the enantiomer of L-lactate, which is measured routinely in clinical practice to assess cell hypoxia. D-lactate has been proposed as a specific marker of gut ischemia-reperfusion (IR), particularly during surgery for ruptured abdominal aortic aneurysms. The aim of this study was to compare the use of D-lactate measurement and colonic tonometry (taken as a reference method) for gut IR detection during elective infrarenal aortic aneurysm (IrAA) surgery. Design: Prospective, monocenter, observational study. Setting: Vascular surgery unit, university hospital. Participants: Candidates for elective IrAA surgery. Interventions: Patients without (controls) and with gut IR (defined as Delta CO2 A > 2.6 kPa) were compared retrospectively. Measurement and Main Results: D-lactate levels were compared with colonic perfusion levels (Delta CO2), as assessed by colonic tonometry, at 7 time points during surgery and until 24 hours after surgery. D-lactate also was measured in mesenteric vein blood before and after gut reperfusion. Plasma TNF-alpha level was measured at the same time points to assess systemic inflammatory response. Eighteen patients requiring elective IrAA surgery were included. The Delta CO2 and TNF-alpha level varied significantly over time. There was a significant Delta CO2 peak at the end of clamping (2.6 +/- 1.8 kPa, p = 0.006) and a significant peak in TNF-alpha level after 1 hour of reperfusion (183 +/- 53 ng/L, p = 0.05). D-lactate levels were undetectable in systemic and mesenteric blood in all the patients throughout the study period. Gut IR patients (n = 6) experienced a longer overall duration of intraoperative hypotensive episodes and received more catecholamines than the controls (n = 12). Conclusions: Compared with colonic tonometry. D-lactate was not a reliable biomarker of gut IR during elective IrAA surgery. (C) 2013 Elsevier Inc. All rights reserved.