Predictors and prognostic implication of early lactate clearance among patients with cardiogenic shock

Lactate clearance has been associated with improved mortality among patients with cardiogenic shock (CS). However, there is scarce information on which characteristics or interventions are associated with early lactate clearance.

We sought to identify predictors of lactate clearance on the first day of admission and estimate its prognostic implications for in-hospital mortality among patients with CS.

We identified adults aged ≥18 years admitted from October 1, 2015, to June 30, 2023, with a diagnosis of CS from a Clinical Data Base, which includes >1,000 hospitals across the United States. The first lactate level on the day of admission was used as a reference, with 2.5 mmol/L as the upper limit of normal. We first analyzed the association of early lactate clearance with in-hospital mortality using adjusted logistic regression, and how the change in lactate–regardless of its initial value–was associated with mortality. Separately, we used multivariable logistic regression to determine sociodemographic, clinical, and hospital-level variables associated with achieving normal lactate levels on the same day of admission.

We identified 297,597 patients with CS and available lactate data. The mean (SD) age was 65.0 (±15.1), 37.5% were women, and the average (SD) first lactate was 4.1 mmol/L (±3.9). Of these, 157,497 (52.9%) had elevated lactate on admission, of which 51,484 (32.7%) subsequently achieved normal lactate levels. Early lactate clearance was associated with lower in-hospital mortality (aOR 0.49; 95% CI 0.48–0.50) and changes in lactate demonstrated a positive exponential relationship with in-hospital death (Figure 1). After multivariable adjustment, the interventions with the strongest association with same-day lactate clearance were the use of a pulmonary artery catheter (PAC) (OR 1.48; 95% CI 1.42–1.55), followed by milrinone (OR 1.30; 95% CI 1.24–1.36) and norepinephrine (OR 1.22; 95% CI 1.19–1.25; Figure 2). Use of epinephrine was the intervention associated with the lowest odds of lactate clearance (OR 0.62; 95% CI 0.60–0.64).

Nearly 1 in 3 patients with CS and hyperlactatemia achieved a normal lactate level on the day of admission, with an associated significant reduction in mortality. In multivariable analysis, the use of PAC had the strongest association with lactate clearance, whereas the use of epinephrine was associated with the lowest odds.