Abstract 13038: Association of Hemolysis Biomarkers and Acute Kidney Injury in Cardiogenic Shock Patients Supported With Impella Ventricular Assist Device

Abstract

Introduction: Hemolysis is a frequent complication in cardiogenic shock patients supported with Impella and can lead to acute kidney injury (AKI). We assessed the association between three hemolysis biomarkers, lactate dehydrogenase (LDH), plasma-free hemoglobin (pfHb), and haptoglobin, and AKI to determine the optimal biomarker in predicting AKI. Methods: Cardiogenic shock patients on Impella support (CP or 5.0) for more than 24 hours from 6/1/2016 to 9/1/2020 at the University of Washington Medical Center were retrospectively enrolled. By institutional protocol, the three biomarkers were measured daily while patients were on Impella support. The association between each biomarker and the development of stage 2 or worse AKI (creatinine increase of ≥ 100% or requiring hemodialysis) within 24 hours of biomarker collection was assessed using logistic regression. Plots of AKI probability over the range of values of each biomarker were constructed using natural splines. Results: Out of 251 included patients (mean age 56.2 ± 15.8 years, 78% male, 69% white), 128 (51%) developed stage 2 or worse AKI. LDH and pfHb values had statistically significant associations with the development of stage 2 or worse AKI within 24 hours of each measurement (OR 1.016 [95% CI 1.009-1.022] per 100 IU/L of LDH, OR 1.092 [95% CI 1.067-1.117] per 10 mg/dL of pfHb, p-value < 0.001 for both) while haptoglobin values did not (p-value 0.6). The association with AKI was stronger for pfHb compared to LDH (McFadden’s R 2 0.12 for pfHb vs 0.03 for LDH). The association of each biomarker and AKI is illustrated in Figure 1. Conclusions: In cardiogenic shock patients supported with Impella, higher LDH and pfHb values were associated with AKI while haptoglobin values were not, and pfHb had a stronger association with AKI than LDH. Our results support the use of pfHb to detect hemolysis and risk of impending AKI in patients supported with Impella. Figure 1. Probability of stage 2 or worse AKI based on biomarker values.