Automated Measurement of Plasma Cell-Free Hemoglobin Using the Hemolysis Index Check Function.

Background: The Roche Cobas chemistry analyzer's hemolysis index (HI) check function can directly report hemoglobin (Hb) concentrations. We aimed to validate the HI check function for the measurement of plasma cell-free Hb.

Methods: Plasma samples (6 μl) were taken by the analyzer and diluted in normal saline to measure the absorbance for Hb at 570 and 600 nm.