Design of an algorithm for the detection of intravenous fluid contamination in clinical laboratory samples.

OBJECTIVES: Contamination of blood samples from patients receiving intravenous fluids is a common error with potential risk to the patient. Algorithms based on the presence of aberrant results have been described but have the limitation that not all infusion fluids have the same composition. Our objective is to develop an algorithm based on the detection of the dilution observed on the analytes not usually included in infusion fluids. METHODS: A group of 89 cases was selected from samples flagged as contaminated. Contamination was confirmed by reviewing the clinical history and comparing the results with previous and subsequent samples. A control group with similar characteristics was selected. Eleven common biochemical parameters not usually included in infusion fluids and with low intraindividual variability were selected. The dilution in relation to the immediate previous results was calculated for each analyte and a global indicator, defined as the percentage of analytes with significant dilution, was calculated. ROC curves were used to define the cut-off points. RESULTS: A cut-off point of 20 % of dilutional effect requiring also a 60 % dilutional ratio achieved a high specificity (95 % CI 91-98 %) with an adequate sensitivity (64 % CI 54-74 %). The Area Under Curve obtained was 0.867 (95 % CI 0.819-0.915). CONCLUSIONS: Our algorithm based on the global dilutional effect presents a similar sensitivity but greater specificity than the systems based on alarming results. The implementation of this algorithm in the laboratory information systems may facilitate the automated detection of contaminated samples.

Experience on how to implement a preanalytical and POCT unit in Madrid's IFEMA field hospital during this unprecedented COVID-19 emergency.

To fight the virus SARS-CoV-2 spread to Europe from China and to give support to the collapsed public health system, the Spanish Health Authorities developed a field hospital located in the facilities of Madrid exhibition centre (IFEMA) to admit and treat patients diagnosed with SARS-CoV-2 infectious disease (COVID-19). The Department of Laboratory Medicine of La Paz University Hospital in Madrid (LMD-HULP) was designated to provide laboratory services. Due to the emergency, the IFEMA field hospital had to be prepared for patient admission in less than 1 week and the laboratory professionals had to collaborate in a multidisciplinary group to assure that resources were available to start on time. The LMD-HULP participated together with the managers in the design of the tests portfolio and the integration of the healthcare information systems (IS) (hospital IS, laboratory IS and POCT management system). Laboratorians developed a strategy to quickly train clinicians and nurses on test requests, sample collection procedures and management/handling of the POCT blood gas analyser both by written materials and training videos. The IFEMA´s preanalytical unit managed 3782 requests, and more than 11,000 samples from March 27th to April 30th. Furthermore, 1151 samples were measured by blood gas analysers. In conclusion, laboratory professionals must be resilient and have to respond timely in emergencies as this pandemic. The lab's personnel selection, design and monitoring indicators to maintain and further improve the quality and value of laboratory services is crucial to support medical decision making and provide better patient care.