PROPPR: 1:1:1 vs 1:1:2 in Massive Trauma Transfusion

1:1:1 didn't beat 1:1:2 on 24-h or 30-day mortality, but achieved hemostasis faster.

Population

680 severe trauma patients across 12 Level-1 trauma centers predicted to need massive transfusion.

Intervention

1:1:1 ratio (1 unit plasma : 1 platelet : 1 PRBC, with each 'platelet' being 1/6 of an apheresis unit).

Comparison

1:1:2 ratio (less plasma + platelets per unit PRBC).

Outcome

All-cause mortality at 24 h and 30 days.

Pragmatic RCT. Patients allocated to receive blood products in the assigned ratio until trauma surgeons declared hemostasis. Crossover allowed if needed. Investigators tracked products delivered, time to hemostasis, complications.

• 24-hour mortality: 12.7% (1:1:1) vs 17.0% (1:1:2). Difference NOT statistically significant (p=0.12) — primary endpoint negative.
• 30-day mortality: 22.4% vs 26.1%. Also not significant (p=0.26).
• BUT: 1:1:1 group achieved anatomic hemostasis FASTER (median 105 vs 137 min) and had fewer deaths from exsanguination at 24 h (9.2% vs 14.6%, p=0.03).
• No increase in transfusion-related complications (TRALI, ARDS, sepsis) with 1:1:1 despite more plasma + platelets.

PROPPR's primary outcome was statistically negative, but practice has converged on 1:1:1 because the secondary outcomes — faster hemostasis, fewer exsanguination deaths — favor it without a safety penalty. Modern MTP packages assemble 1:1:1 as the default. Use TEG/ROTEM to refine when available, but don't wait for it during active hemorrhage.

• Underpowered for primary mortality endpoint.
• Open-label.
• Civilian trauma centers only — military/austere settings may differ.
• Did not include TXA — CRASH-2 + WOMAN now standard alongside MTP.

1. How does your institution define MTP activation criteria? Do you use a 1:1:1 default package?
2. When would TEG/ROTEM-guided product selection deviate from 1:1:1?
3. PROPPR didn't show a mortality difference — should that worry us, or is the secondary outcome of faster hemostasis sufficient?