Effect of Hemoglobin Levels in Patients with Cardiogenic Shock of Any Cause: Insights from a Single-Centre, Prospective Registry

Background: Data regarding the short-term prognostic impact of hemoglobin levels in cardiogenic shock (CS) patients is limited. The study examines the prognostic impact of hemoglobin levels in patients with CS.Methods: Consecutive patients with CS of any etiology from 2019 to 2021 were included at one institution. Hemo-globin levels were retrieved from the day of admission (i.e., day 1), and on days 2, 3, 4, and 8 of intensive care unit (ICU) treatment thereafter. The primary endpoint was 30-day all-cause mortality. Statistical analyses included univariable t-tests, Spearman's correlations, C-statistics, Kaplan-Meier analyses as well as multivariable logistic and Cox regression analyses.Results: From a total of 250 consecutive patients admitted with CS, 54% died within 30 days. Hemoglobin levels on day 4 and on day 8 were associated with moderate discrimination for 30-day all-cause mortality (area under the curve (AUC) 0.598 -0.666), whereas hemoglobin level on day 1 was not predictive for 30-day all-cause mortali-ty (AUC = 0.504). There was no association with 30-day all-cause mortality when stratified by the presence of anemia (defined as hemoglobin level < 12 g/dL) on day 1 (54% vs. 55%; log rank p = 0.906; HR = 0.981; 95% CI 0.698 -1.378; p = 0.910). However, a decrease of hemoglobin by > 2 g/dL from day 1 to day 3 of ICU treatment was associated with an increased risk of 30-day all-cause mortality (56% vs. 41%; log rank p = 0.014; HR = 1.831; 95% CI 1.108 -3.026; p = 0.018). Conclusions: Hemoglobin levels on day 1 were not associated with prognosis in CS. However, an early decrease of hemoglobin levels from day 1 to day 3 indicated impaired short-term prognosis in CS patients.