Improvement of preanalytical screening interference on coagulation tests by auto checking system

Objective To investigate the potential improvement of sample quality by automatic pre-analysis sample checking system, comparing to visual inspection for coagulation tests routinely. Methods Thirty samples with hemolysis, Icteric and lipemia in different levels were prepared and issued to 13 technicians for visual check, to evaluate the consistency individually. 2 949 blood samples with order for coagulation test were collected in Beijing Chaoyang Hospital in April and May 2018, the quality of all samples was evaluated by both visual check and automatic sample quality checking system before analysis, performance of two measurements detecting hemolysis, lipid, icteric or clot was compared. Results Significant differences were found in visual check among operators. The Kappa coefficients in three randomly selected groups were 0.32, 0.26 and 0.38 respectively, indicating that the consistency of visual check was poor. Among all investigated samples, 3 samples with unacceptable interference were detected visually, including 2 samples with hemolysis and another one with lipemia. On the other hand, 19 unqualified samples were identified by automatic checking system. Five types of interference of unqualified samples were detected as icteric (26.32%,5/19), clot (21.05%,4/19) hemolysis (5.26%,1/19),lipemia (36.84%, 7/19), and hemolysis with lipemia (10.53%,2/19) respectively by automatic checking system. But one case of hemolysis sample rejected by visual check was not rejected by automatic sample quality checking system.7 samples were merely affected on D-dimer by lipemia, which level did not influence the results of prothrombin time(PT) and activated partial thromboplastin time (APTT). Notably, other two samples were interfered with not only tests of PT, APTT and fibrinogen by hemolysis, but also D-dimer by the considerable level of lipemia, which showed the superiority of test-specific quality checking features. Conclusions The automatic pre-analysis sample quality checking system can improve the detection rate of unqualified samples and improve the efficiency of routine, helping realization of total quality management. Key words: Sampling; Coagulation test; Total quality management