Institutional MTP criteria during the study period
| Admission clinical criteria | Operating room clinical criteria | Laboratory criteria |
| SBP ≤70 mm Hg | Non-surgical hemorrhage | Base deficit >8 |
| Crystalloid >4 L | EBL >150 cc/min | International Normalized Ratio >1.4 |
| Estimated Blood Loss (EBL) >1000 cc | Prothrombin Time >18 s | |
| SBP <90 despite 3.5 L crystalloid | Partial Thromboplastin Time >60 s | |
| Temperature <34°C | Admission Hct <30 | |
| ISS >25 | pH <7.1 |
Only one of the criteria had to be met for activation of massive transfusion protocol.
ISS, Injury Severity Score; SBP, systolic blood pressure.