[Preanalytical phase and accreditation: acceptance criteria for samples of multisite laboratory].

Performing high quality analyses in order to help physicians in their diagnoses and to ensure better patient care: this represents our routine mission for clinical lab. To achieve this goal, all steps from sampling to the final data transfer must be controlled. The preanalytical phase is one of the most crucial, but also one of the most complicated, especially in the context of a consolidated laboratory network. Transport conditions, delays, temperature, regulatory constraints are all criteria that we need to take into consideration in order to comply to ISO 15189, section 5.4. In this context, our laboratory would like to address the following issues: to control the transport conditions in order to guarantee optimal preservation of the samples, and to define an internal process and identify non-conforming situations linked to delay in sample delivery. An original study dealing with the stability in whole blood of common clinical chemistry and immunochemistry tests in defined transport conditions (delays, temperature, tube position) was performed on a panel of 100 patients' samples. This panel is intended to be a good reflection of the patients usually seen in multi-site laboratory. We observed that most of the analytes (35 of 41) were stable in whole blood; however, some of them demonstrated instability over time. All these results were integrated into our collection manual.