Agreement of point-of-care and laboratory lactate levels among trauma patients and association with transfusion.

Background and objectives: In the setting of trauma and suspected critical bleeding, indications to commence blood transfusions remain unclear, with high rates of potentially avoidable transfusions. Prehospital blood lactate measurements could help predict the need for blood transfusions. The aim of this study was to compare measurements detected by a point-of-care (POC) lactate device with laboratory measured lactate levels.

Materials and methods: This was a cross-sectional study conducted in the emergency department. Eligible patients were those with suspected major trauma and critical bleeding. Venous or arterial blood samples were collected. POC measurements of lactate levels were conducted using a StatStrip Xpress® lactate meter and compared with laboratory values.

Results: Among 70 patients, the mean difference between the POC and laboratory lactate results was -0.19 mmol/L, with limits of agreement at -1.9 and 1.5. Most measurements (n = 66; 94.3%) were within the limits of agreement. A POC lactate level of >3.3 mmol/L had >90% specificity for transfusion, whereas a level <1.4 mmol/L had 90% sensitivity to rule out a transfusion.

Conclusion: The level of agreement of POC lactate with the laboratory lactate was high. Research on clinical decision rules for pre-hospital transfusion that incorporate POC lactate measures is therefore feasible.