Impact of Preanalytical Storage Time and Air Exposure on ROTEM and Coagulation Sample Stability

The preanalytical phase of blood sample collection, storage, and transportation is crucial in clinical laboratory practice. This study examined the impact of preanalytical storage time and the presence of air in the test tube on viscoelastic and traditional coagulation tests and platelet activation markers.

Blood samples from ten healthy donors were divided into Vacuette sodium citrate and K2E EDTA tubes, with and without air, and stored at room temperature with gentle agitation for up to 48 h. Coagulation tests (ROTEM, APTT, INR, and PTF1 + 2), platelet activation markers (β-thromboglobulin and sP-selectin), blood gases and metabolites (pH, pCO₂, pO₂, bicarbonate, hemoglobin, sO₂, K⁺, Ca²⁺, glucose, and lactate), and hemolysis (free hemoglobin and absorbance) were measured.

In citrated blood samples, ROTEM parameters, APTT, and PTF1 + 2 remained stable during 6 hours of storage at room temperature, and INR was stable for 48 h. In EDTA blood, β-thromboglobulin increased initially and then remained stable for 6 hours. sP-selectin remained stable for 6 hours. In EDTA blood samples, hemolysis remained minimal during storage, but cell death revealed by a lactate dehydrogenase increase was observed after 24 h. Blood gases and metabolites exhibited rapid changes, underscoring the need for immediate analysis. No significant differences were observed between samples with and without air in the test tubes.

ROTEM, APTT, PTF1 + 2, and platelet activation markers were stable for 6 h and INR was stable for 48 h. Removing ambient air from blood samples did not extend preanalytical stability. These insights are valuable for optimizing preanalytical practices in clinical laboratories, potentially improving patient care and reducing costs.