The value of lactate clearance in admission decisions of patients with acute exacerbation of COPD.

Background: Lactate and lactate clearance are being used as biomarkers in several critical conditions. The aim of this study was to examine the value of sixth hour lactate clearance in patients who were hospitalized with chronic obstructive pulmonary disease (COPD) exacerbations.

Methods: This single-center, cross-sectional study was conducted in a tertiary emergency department (ED) on patients who presented with acute exacerbation of COPD. Discharge or admission decisions were specified according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria and the clinician's decision. In the study, lactate clearance was defined as the percent decrease in lactate from the time of presentation to the ED to the sixth hour.

Results: A total of 495 patients were evaluated and 397 patients were excluded. Among included patients, 53 (54.1%) were admitted to the hospital and 45 (45.9%) were discharged. The median lactate clearance was found to be -11.8% (95% CI: -50.0 to 34.5) in the admitted group and 14.7% (95% CI: -11.3 to 42.3) in the discharged group. Between the two groups, the median difference of lactate clearance was found to be 26.5% (95% CI: 0.6 to 52.4). Multivariate logistic regression analysis revealed that the delta lactate value can determine the hospitalization need of patients (OR: 0.91, 95% CI: 0.85 to 0.97).

Conclusion: Lactate clearance can be evaluated as a useful marker in patients with COPD exacerbations. This study suggests that lactate monitoring in the ED has clinical benefits in addition to GOLD guidelines when deciding whether to discharge or hospitalize a patient.