Optimization of operational flow of D-Dimer test in a core laboratory in a brazilian tertiary hospital to ensure operational efficiency during the COVID-19 pandemic

Background : D-dimer tests are very important tests in follow-up and treatment of patients affected by infection by SARS-COV-2. These results are directly related to morbidity and mortality. Due to high and sudden demand, our institution faced to an unacceptable risk of lack of reagents, concomitantly to an increase of employees' sick pay in the laboratory's team. Aims : The present study aims to demonstrate the need to modify the flows of processing the laboratory tests in a critical situation, and with it offer to our clients a quick and reliable result. Methods : Before the pandemic, D-dimer tests were performed in two different methodologies. First, by immunoturbidimetry and for confirmation, just for results above 500 ng/ml, a immunoenzymatically test used to realized, both by automated equipment. This check was necessary for decreasing the risk for false-positive in patients affected by thrombosis. In the face of a risk scenario, we performed a fishbone diagram to identify possible causes for an effect or problem and a PDCA (plan-do-check-act) cycle to minimize the risks (Figure 1). In the first phase (PLAN), we planned a many actions involving doctors and laboratory professionals with the aim of reduce by 80% of repetitions of this test in 6 months. In the second phase (DO), we started a new flow operational, performed the test with just one methodology with close monitoring by medical team. Results : Checking our operational results (third phase), was observed 96% decrease in repetitions in 6 months (April to September) with an important cost reduction from around 27% (Figure). Conclusions : This joint work enabled a optimization of the equipments and reagents, wilth a improvement of our produtivity without losses of quality and security. Now we are in the last phase, when we are consolidating our new flow, with quarterly evaluations and continuous monitoring of technical and economical results.