Preanalytical phase management: identification and control of nonconformities in the sampling room of a clinical laboratory in Tunisia

In the total analytical process of clinical specimens, there are many possible preanalytical sources of error. The objective of this work was to evaluate the overall level of conformity of the internal preanalytical phase according to ISO 15189: 2012 and the guideline of laboratories practice in the laboratory of clinical biochemistry of Charles Nicolle hospital, Tunis. In order to identify and understand the failures in the preanalytical process, we have established an internal audit methodology to verify the accordance of different process with the requirements of the quality management systems. The nonconformities noted by the internal audit were mostly related to the execution of sampling, the medical prescription and the transmission of laboratory samples. To improve and ensure quality we have used quality tools, implemented corrective actions and re-evaluated the frequency of nonconformities to verify the effectiveness of the actions implemented. The total number of nonconformities was reduced by 52% after the application of quality tools. The results of the corrective action investigation showed a highly significant difference (P=0,004) of the percentage of nonconformities before and after corrective actions. The application of an internal audit methodology was a promising method to contribute to the enhancement of patient safety and produce valuable benefits for the entire healthcare system. However, the actions put in place remain insufficient on some nonconformities. Thus, the laboratory must ensure human and financial mobilization and full commitment and cooperation of the entire laboratory staff.