Massive transfusion in trauma: blood product ratios should be measured at 6 hours.

Background: Most potentially preventable haemorrhagic deaths occur within 6 h of injury. Conventionally, blood component therapy delivery is measured by 24-h cumulative totals and ratios. The study aim was to examine the effect of a massive transfusion protocol (MTP) on early (6 h) balanced component therapy.

Methods: An 88-month retrospective clinical study at a level 1 trauma centre was undertaken, examining consecutive trauma patients receiving ≥10 units of packed red blood cells (PRBCs) within 24 h, before (pre-MTP) and after implementation of MTP. Demographic data, injury severity score (ISS), abbreviated injury scale (AIS), shock parameters, coagulation profile, the need for surgical intervention (<24 h), mortality and intensive care unit length of stay were collected. The ratios of blood products given by 6 h, by 24 h and the time between administrations of components was collected and analysed.

Results: Pre-MTP and MTP patients had similar demographics, shock severity and initial laboratory findings. Despite MTP patients having had a higher ISS (42 ± 12 versus 36 ± 12, P < 0.05) and AIS head score (2.6 ± 1.8 versus 1.6 ± 2.0, P < 0.05), there was no difference in mortality. Area under the curve (AUC) of the MTP period showed earlier delivery of higher median ratios of fresh frozen plasma (FFP)/PRBC (P= 0.004). Similar findings were found for cryoprecipitate/PRBC and platelet/PRBC ratios. By 24 h, the AUC for FFP/PRBC ratios were no different.

Discussion: Implementation of MTP resulted in earlier balanced transfusion. The difference between the FFP/PRBC ratios of the two types of resuscitations levelled by 24 h. The efficacy of component therapy delivery should be measured earlier than 24 h.