What is the initial amount of blood transfused in a trauma situation in the Emergency Department (ED)?

Initial Blood Transfusion in Trauma Situations in the Emergency Department

In trauma situations requiring massive transfusion, the initial approach should be a high-ratio transfusion strategy of 1:1:1 (plasma:platelets:packed red blood cells) to reduce early mortality and improve hemostasis. 1

Initial Blood Product Administration

First-Line Blood Products

• Packed Red Blood Cells (PRBCs):

  • Initial transfusion typically consists of 4-8 units of PRBCs 2
  • Group-specific blood can be issued without antibody screening 2
  • O-negative blood should only be used if blood is needed immediately 2, 1

• Fresh Frozen Plasma (FFP):

  • Early infusion of FFP at 15 ml/kg should be initiated if massive hemorrhage is anticipated 2, 1
  • High FFP:RBC ratio (1:1 to 1:2) is associated with improved outcomes in trauma patients 2
  • Established coagulopathy will require more than 15 ml/kg of FFP to correct 2

• Platelets:

  • Initial dose of 4-8 platelet concentrates or one apheresis pack 2
  • Maintain platelet count above 50 × 10^9/l for general trauma 2
  • Aim for platelet count above 100 × 10^9/l in patients with multiple trauma who are severely bleeding or have traumatic brain injury 2, 3

Transfusion Ratios

• The 1:1:1 ratio (plasma:platelets:PRBCs) is recommended for severely traumatized patients 2, 1
• Military experience has shown better outcomes with high plasma:RBC ratios 2
• Studies demonstrate that trauma patients receiving platelets and RBCs at a ratio of 1:5 or greater had lower 30-day mortality (38% vs 61%) 2

Monitoring During Massive Transfusion

• Coagulation Parameters:

  • Monitor fibrinogen levels (target >1 g/L) 2, 1
  • A fibrinogen <1 g/L or PT/aPTT >1.5 times normal represents established hemostatic failure 2
  • Consider viscoelastic testing (TEG, ROTEM) for rapid evaluation of hemostasis 1

• Other Critical Monitoring:

  • Ionized calcium levels should be monitored during massive transfusion 1
  • Acid-base status should be regularly assessed 4
  • Early correction of metabolic derangements decreases coagulopathy 5

Special Considerations

• Traumatic Brain Injury:

  • Higher platelet transfusion threshold (100,000/mm³) for patients with TBI 3
  • Early empirical FFP infusion may increase the risk of delayed traumatic intracerebral hematoma in severe head injury 2
  • For patients on anticoagulation therapy, reversal should be prioritized 3, 6

• Timing Considerations:

  • Earlier blood product administration is associated with improved survival 4
  • Prehospital transfusion of plasma and RBCs has been associated with improved acid-base status on hospital admission 4
  • Starting therapeutic anticoagulation too soon after trauma (5.5 vs 10.0 days) was associated with higher transfusion requirements 6

Implementation Considerations

• Hospital Protocol:

  • Every hospital must have a major hemorrhage protocol that can be mobilized immediately 2, 1
  • Immediate control of obvious bleeding is paramount (pressure, tourniquets, hemostatic dressings) 2, 1
  • In hospitals where massive hemorrhage is frequent, locally developed "shock packs" may be helpful 2

• Post-Resuscitation Care:

  • Standard venous thromboprophylaxis should be commenced as soon as possible after hemostasis has been secured 2, 1
  • Patients develop a prothrombotic state following massive hemorrhage 2

Common Pitfalls to Avoid

• Delayed Activation: Failure to activate massive transfusion protocol early can lead to preventable mortality
• Under-transfusion: Inadequate plasma and platelet transfusion relative to RBCs can worsen coagulopathy
• Over-reliance on O-negative blood: Should only be used when blood is needed immediately before group-specific blood is available
• Ignoring fibrinogen levels: Fibrinogen replacement is critical and may require fibrinogen concentrate or cryoprecipitate
• Neglecting calcium replacement: Hypocalcemia from citrate toxicity can worsen coagulopathy and cardiac function

Remember that massive transfusion is typically defined as transfusion of ≥10 units of PRBCs within 24 hours or ≥6 units within 6 hours 1, but protocols should be activated based on clinical assessment of severe bleeding rather than waiting for specific thresholds to be met.