Objective: The laboratory critical values are the laboratory testing results which required attention or action by the physicians. The aim of this study is to investigate the laboratory critical value notification process in our laboratory in terms of patient safety and clinical decision efficiency and to compare our prevalence of laboratory critical values with the data in the literature.

Materials and Methods: In this retrospective study, we performed analysis of laboratory critical values from data obtained by the laboratory information system during 2 years (between 01.01.2018- 31.12.2019). The laboratory critical values were identified by clinical chemistry laboratory according to guidelines.

Results: The laboratory critical value was found by 0.22% of total laboratory tests. We determined 5322 notification, of which 21.2% came from emergency units, 46.2% from intensive care units, 18.2% from routine inpatients and 14.4% from routine out patients. The highest rate of laboratory critical values was showed for partial oxygen pressure (18.7%), followed by white blood cell and platelet count (10.4% and 9.8%) concentrations. According to department, the highest rate of the laboratory critical values notification were partial oxygen pressure, glucose, hemoglobin tests for emergency patients, were platelet count, white blood cell and creatinine tests for inpatients, were prothrombin time and white blood cell tests for outpatients and were partial oxygen pressure and white blood cell tests for intensive care units. Mean time of laboratory critical values notification was 12 minute and timely notification ratio was 76% for all departments.

Conclusions: The analysis of laboratory critical values notification in our hospital is in suitable with that declared in the literature. This study will contribute in the establishment of international harmonized postanalytical phase-related criteria and indicators of the laboratory critical value notification.