Gestão da qualidade no laboratório clínico: análise do controle interno da qualidade no setor da hematologia

Abstract

Clinical laboratories play a fundamental role in the prevention, diagnosis, monitoring and treatment of diseases through the tests they carry out. To this end, these establishments must adhere to strict quality standards and always seek methodological advances. Internal quality control (IQC) is one of the tools used to monitor a test's performance, allowing professionals to identify and correct problems before they affect patient results. The aim of this study was to evaluate the effectiveness and reliability of IQC data in the hematology department of a clinical laboratory. For this purpose, IQC data from a laboratory in Campina Grande/PB was selected over a period of one month. Statistical analysis was carried out on the data from the differential microscopic count of the white series, using the Rümke table and Chauvenet statistics. The IQC analysis of the automated parameters, red blood cell count, total leukocytes and platelets, hemoglobin dosage and hematocrit determination was carried out using the Levey-Jennings Graph in conjunction with Westgard's multiple rules. The results of the microscopic evaluation showed that, when comparing the Rümke Table and the Chauvenet Statistic, the former showed all the data within acceptable values, thus guaranteeing the reliability of the results released by the analyzers. By contrast, the Chauvenet statistic indicated that 12.96% of the differential leukocyte count values were minimally out of the acceptable range, showing that this method is more sensitive to detecting errors quickly than the other. As for the automated parameters, they revealed the majority of acceptable values, with Westgard rules being infringed on some of the days evaluated, indicating the occurrence of random and systematic errors. These results demonstrated the importance of IQC in health services, highlighting that effective evaluation can significantly contribute to the release of accurate results, through the early detection of deviations and errors, allowing immediate correction and minimizing negative impacts on patient outcomes.