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 ΔCO2>2.6 kPa) were compared retrospectively.
Measurement and main results: D-lactate levels were compared with colonic perfusion levels (ΔCO2), 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-α level was measured at the same time points to assess systemic inflammatory response. Eighteen patients requiring elective IrAA surgery were included. The ΔCO2 and TNF-α level varied significantly over time. There was a significant ΔCO2 peak at the end of clamping (2.6±1.8 kPa, p = 0.006) and a significant peak in TNF-α 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.
Keywords: abdominal; aortic aneurysm; d-lactate; inflammation mediators; mesenteric vascular occlusion; reperfusion injury.
Copyright © 2013 Elsevier Inc. All rights reserved.