Whole blood hemolysis detection on the GEM^® Premier™ 7000: performance across hemoglobin A, S, and F

Point-of-care blood gas analyzers are essential in critical care settings but remain vulnerable to pre-analytical interferences, particularly hemolysis, which may lead to erroneous potassium results. The GEM^® Premier™ 7000 incorporates an onboard hemolysis detection system based on multi-wavelength co-oximetry, allowing direct estimation of free hemoglobin in whole blood samples. This study evaluated the analytical performance of this system across different hemoglobin variants, including fetal hemoglobin (HbF) and hemoglobin S (HbS).

Fifty patient samples undergoing routine arterial blood gas and biochemical testing were analyzed using the GEM^® Premier™ 7000, and Atellica Solution analyzers. Experimental hemolysis was induced to evaluate the performance of the onboard hemolysis detection system. In a second step, hemoglobin overload experiments using HbA₀, HbF, and HbS were performed in samples from 10 healthy volunteers to assess the robustness of hemolysis detection across different hemoglobin variants.

Experimental hemolysis significantly increased the hemolysis index and potassium concentrations measured on the GEM^® Premier™ 7000, with median hemolysis index values rising from 1 to 6 and median potassium concentrations from 3.6 to 9.8 mmol/L (p<0.001). The GEM^® Premier™ 7000 accurately detected increasing concentrations of free HbA₀, HbS, and HbF throughout the overload experiments.

The integrated hemolysis detection system reliably detected clinically significant hemolysis in whole blood samples, supporting more reliable point-of-care blood gas testing.