Simulation Study on Preanalytical Variables in Coagulation Testing: Interference Effects and Threshold Determination of Hemolysis, Lipemia, Icterus and Insufficient Sample Volume.

ObjectiveTo systematically evaluate the interference degree of hemolysis, lipemia, icterus, and sample collection volume on routine test items of the ACL TOP750 automatic coagulation analyzer, assess the technical performance of the HIL module, verify the manufacturer's anti-interference capability, and establish laboratory-specific anti-interference thresholds for optimizing preanalytical quality management.MethodsGradient interference models of hemolysis, icterus, and lipemia, as well as sample systems with different collection volumes, were constructed. Seven routine coagulation indicators (PT, aPTT, FIB, TT, DD, FDP, AT) were detected, with a relative bias (Bias%) of 10% set as the acceptable standard to comprehensively evaluate the instrument's anti-interference ability.ResultsThe H-index of ACL TOP750 was highly linearly correlated with hemoglobin concentration, the I-index with total bilirubin, and the L-index with triglyceride concentration (R2 ≥ 0.951). For hemolysis: TT bias was >10% at H ≥ 650 mg/dL, FIB bias was unacceptable at H ≥ 880 mg/dL, and DD bias was >10% at H ≥ 270 mg/dL. For lipemia, DD bias was >10% at L ≥ 1100 mAbs, and ultracentrifugation effectively improved lipemia interference. For icterus, aPTT bias was unacceptable at I ≥ 35 mg/dL, and PT and FIB biases were >10% at I ≥ 38 mg/dL. At a sample filling ratio of 70% (2.1 mL), biases of several analytes exceeded the acceptable limits; accordingly, 70% was defined as the threshold for sample rejection.ConclusionThe HIL module of the ACL TOP750 testing system exhibits excellent performance, and its anti-interference capability meets the manufacturer's specifications. The optimized HIL index and sample volume anti-interference thresholds established in this study are more in line with clinical practice.