Effects of hemolysis, bilirubin, and lipemia interference on coagulation tests detected by two analytical systems.

The present study detected analytical interferences such as lipemia (>500 mg/dL) on coagulation tests on the optical analyzer. We also found a biological impact on the results in case of hemolyzed sample: Fibrinogen was decreased when the hemoglobin level was superior to 1.8 g/L, PT was prolonged beyond 5 g/L, and aPTT was shortened beyond 1.5 g/L hemoglobin concentration, especially in patients treated with heparin. Above these thresholds, it is important not to give results that could influence the clinical decision.