Trauma Resuscitation With Low-Titer Group O Whole Blood or Products

Inclusion Criteria: 1. Adult trauma patient (estimated age \> 15 or weight \> 50 kg, if age unknown) 2. Patient taken to trauma center directly from scene 3. Commencement of blood transfusion (PRBC, plasma or LTOWB), in pre-hospital or in-hospital setting 4. Activation of site-specific Massive Hemorrhage Protocol or Massive Transfusion Protocol 5. Traumatic injury with at least one of the following: 1. Confirmed or suspected acute major bleeding 2. Assessment of Blood Consumption (ABC) Score ≥2 Exclusion Criteria: 1. Patients who have received, prehospital or in-hospital more than two units of LTOWB; the equivalent in components (two units of packed red blood cells and two units of plasma); or a combination of the two (more than one unit of LTOWB, one unit of packed cells, and one unit of plasma). Most trauma centers hold two units of either packed red blood cells (with two units of plasma) or two units of LTOWB in the emergency department. This stock is used to initiate transfusion, while the massive hemorrhage protocol is activated from the blood bank. 2. Patients transferred from another hospital 3. Children \<15 years (in most communities, patients aged 15-18 years are treated at adult trauma centers, and patients in this age group frequently suffer life-threatening injuries, and will therefore be included) 4. Known prisoners, defined as individuals involuntarily confined or detained in a penal institution (including juvenile detention, involuntary psychiatric commitment, or court-ordered residential substance abuse treatment) 5. Moribund patients expected to die within 1 hour 6. Patients who required an ED thoracotomy or received more than 5 consecutive minutes of cardiopulmonary resuscitation (prior to receiving randomized blood products) 7. Patients with known "do not resuscitate" orders prior to randomization 8. Patients who refuse the administration of blood products 9. Individuals with a research "opt out" bracelet. 10. Greater than 20% total body surface area (TBSA) burns 11. Suspected inhalation injury victims 12. Patients who are obviously pregnant on clinical examination or known to be pregnant as provided by the subject or legally authorized representative