Platelet to erythrocyte ratio and mortality in massively transfused trauma patients.

Background: The optimal transfusion ratio of platelets (PLT), plasma and red blood cells (RBC) in trauma patients with massive haemorrhage is still a subject of discussion. The objective of this study is to assess the effect of platelet transfusion on mortality in trauma patients who received massive transfusion.

Methods: Data were collected from four Dutch level-1 trauma centres. All trauma patients aged ≥ 16 years who received ≥ 6 RBC / 6 h from the time of injury were included. Patients were divided based on PLT:RBC ratio (no platelets, low (<1:5) and high (≥1:5)). Primary outcome measure was 6-hour mortality and secondary outcomes included mortality at other time points and transfusion characteristics.

Results: A total of 292 patients were included. Patients in the high PLT ratio group had lower mortality rates at six and 12 h as compared to the low PLT ratio and no PLT group. In the high PLT group mortality as a result of exsanguination (12 %) was significantly lower as compared to the low PLT group (23 %). High PLT ratio had lower probability for 6-hour mortality multivariable analysis. Higher plasma:RBC ratios were associated with lower mortality at all time points.

Conclusions: Although the optimal patient specific transfusion strategy in patients with traumatic haemorrhage is still not resolved, these results show that higher PLT to RBC ratios are associated with lower early mortality.