l- and d-lactate as biomarkers of arterial-induced intestinal ischemia: An experimental study in pigs

BackgroundIntestinal ischemia is difficult to diagnose, and search for new biomarkers has led to interest in d-lactate, which arises from bacterial fermentation in the gastrointestinal tract.MethodsThe superior mesenteric artery was clamped in eight pigs for 6 h to induce ischemia of the intestine. Eight sham-operated pigs served as controls. Systemic and portal plasma d- and l-lactate were sampled in 1 h intervals. l-LDH was inactivated prior to d-lactate measurement by addition of NaOH.ResultsIn systemic vein samples, we found a significant mean difference in the change of d-lactate from baseline to 6 h between the sham and intervention group (.007 ± .011 mmol/l vs. .030 ± .013 mmol/l, respectively) (P = .020). Both systemic and portal circulation levels of plasma l-lactate increased significantly between the two groups within an hour. The mean difference for l-lactate were −.020 ± .215 mmol/l and 1.440 ± 1.454 mmol/l in the sham and intervention group, respectively (P = .009).Conclusionl-lactate was found to be a marker of arterial-induced intestinal ischemia in both the systemic and portal circulation. There was no significant elevation of d-lactate at either site during the 6 h of ischemia.