This week, NEJM has published the PROPPR trial—Pragmatic Randomized Optimal Platelet and Plasma Ratio—investigating the ratio of blood products used in massive transfusion for severe haemorrhage following trauma.
680 level 1 trauma, "non-moribund" patients with severe haemorrhage were randomised to either platelets : plasma : red cells (PPR) ratios of 1:1:1 or 1:1:2. Baseline characteristics were similar between groups, andother treatment was not controlled as "usual care" at the treating facilities. Both groups received the same number of red cells, so the main difference was in the amount of platelets and plasma received.
The authors report:
- No difference in all-cause mortality at 24 hours and 30 days
The trial was powered to detect a 10% difference at 24 hours and 12% at 30 days
- No difference in the incidence of complications expected from greater exposure to blood products (such as inflammatory-mediated ARDS, multi-organ failure, infection, thromboembolism and sepsis)
Importantly, the 1:1:1 group showed:
- Higher achievement of haemostasis in the first 24 hours
- Lower mortality due to exsanguination in the first 24 hours (9.2% vs 14.6%)
- This was the most common cause of death in the first 24 hours
- The median time to death was longer in the 1:1:1 group (106 minutes vs 96 minutes)
The authors suggest that a larger trial would demonstrate the difference seen to be statistically significant, and that:
Given the lower percentage of deaths from exsanguination and our failure to find differences in safety, clinicans should consider using a 1:1:1 transfusion protocol, starting with the initial units transfused while patients are actively bleeding, and then transitioning to laboratory-guided treatment once hemorrhage control is achieved.
And from Prof Brohi—professor of trauma and special interest in bleeding post trauma:
— Karim Brohi (@karimbrohi) February 3, 2015