Association of lactate clearance with outcomes of patients with gastrointestinal bleeding visiting the emergency department

Abstract

Objective: Lactate clearance is reportedly associated with the outcomes of various critical illnesses. However, few studies have examined the association between lactate clearance and outcomes in patients with gastrointestinal bleeding (GIB). Methods: A single-center retrospective observational study between 2016 and 2020 was conducted. Consecutive adult patients with GIB symptoms (melena, hematemesis, and hematochezia) presenting to the emergency department were included. Lactate clearance was calculated as ([initial lactate-subsequent lactate]/initial lactate)×100. The association between lactate clearance and outcomes was examined by multivariable logistic regression analysis. The primary outcome was the in-hospital mortality. The area under the curve (AUC) of lactate clearance for in-hospital mortality was calculated. The sensitivity and specificity with optimal cutoff values were computed. The AUC of lactate clearance was compared with the Glasgow-Blatchford score and AIMS65 for predicting in-hospital mortality. Results: Three hundred and fifty-one patients were included in the final analysis, and the in-hospital mortality rate was 12%. Lactate clearance was significantly associated with lower in-hospital mortality (odds ratio, 0.991; P=0.016). The AUC of lactate clearance for in-hospital mortality was 0.64. The AUC of Glasgow-Blatchford score and AIMS65 for inhospital mortality was not significantly different from lactate clearance (P=0.759 and P=0.442, respectively). A cutoff lactate clearance of less than 10% had 45.2% sensitivity, 30.7% specificity, 8.2% positive predictive value, and 80.5% negative predictive value for predicting in-hospital mortality. Conclusion: Lactate clearance was independently associated with in-hospital mortality in GIB patients. Further prospective studies will be needed to address the prognostic value of lactate clearance in GIB.