Hemolysis is a recognized complication of a microaxial flow pump (Impella CP) support, but its incidence and associated risk factors remain unclear. We retrospectively analyzed 24 patients with cardiogenic shock who received Impella CP support at a single tertiary center between January 2022 and December 2024. Serial serum haptoglobin measurements were used to assess hemolysis, with low haptoglobin defined as a minimum level of <19 mg/dl during Impella CP support. Clinical variables were compared between patients with and without low haptoglobin, and multivariable logistic regression was performed to identify independent predictors. After applying exclusion criteria, 24 patients who received Impella CP support alone were eligible for this study. Low haptoglobin occurred in 67% (16/24) of patients, with 94% of cases detected within 24 hours of intensive care unit (ICU) admission. Patients with low haptoglobin had significantly higher P-levels and lower pulmonary artery pulsatility index scores at ICU admission. Multivariable analysis identified a P-level ≥5 (odds ratio 63.61; p = 0.001) as an independent predictor of low haptoglobin. In conclusion, low haptoglobin is common during Impella CP support and occurs early after initiation. A higher P-level is associated with low haptoglobin and may help identify patients at increased risk for hemolysis.
Kawakami et al. (Mon,) studied this question.