What are the guidelines for massive transfusion in trauma according to NICE (National Institute for Health and Care Excellence)?

Massive Transfusion Protocol Guidelines in Trauma

For trauma patients with massive bleeding, high-ratio transfusion strategies with at least one unit of plasma per two units of packed red blood cells are recommended to reduce mortality and improve outcomes. 1

Definition of Massive Transfusion

• Massive transfusion is typically defined as transfusion of >10 units of RBC in 24 hours or >6 units in 6 hours 1
• More recent dynamic definitions include replacement of more than 3-4 red cell concentrates within an hour 2

Key Components of Massive Transfusion Protocol in Trauma

Transfusion Ratios

• For trauma patients: High-ratio transfusion strategies (at least 1:2 FFP:RBC) are conditionally recommended based on low certainty evidence 1
• The 1:1:1 ratio (RBC:plasma:platelets) provides the most reasonable approach to initiate empiric transfusion when massive hemorrhage is suspected 1
• Military and civilian observational studies show mortality benefits with high transfusion ratios ranging from 1:1 to 1:2 FFP:RBC 1
• Randomized controlled trials show improved clinical hemostasis and reduced death by exsanguination with higher transfusion ratios, though overall mortality benefits were less pronounced than in observational studies 1
• The 1:1:1 regimen is particularly indicated for the most severely traumatized patients 1

Implementation Considerations

• Hospitals must have a major hemorrhage protocol in place that includes clinical, laboratory, and logistic responses 1
• The protocol should be mobilized immediately when massive hemorrhage is declared 1
• Immediate control of obvious bleeding is paramount (pressure, tourniquet, hemostatic dressings) 1
• Early infusion of FFP (15 ml/kg) should be used if a senior clinician anticipates massive hemorrhage 1
• Established coagulopathy will require more than 15 ml/kg of FFP to correct 1

Laboratory Targets and Monitoring

• A fibrinogen <1 g/L or PT and aPTT >1.5 times normal represents established hemostatic failure and predicts microvascular bleeding 1
• Maintain a minimum target platelet count of 75 × 10^9/L 1
• Consider using fibrinogen concentrate (3-4g) or cryoprecipitate for rapid fibrinogen replacement when levels are <1.5-2.0 g/L 1

Logistical Considerations

• Group-specific blood can be issued without performing an antibody screen as patients will have minimal circulating antibodies 1
• O negative blood should only be used if blood is needed immediately 1
• In hospitals where massive hemorrhage is frequent, locally developed "shock packs" may be helpful 1
• Standardized protocols improve the speed of blood product delivery (41.7 vs 62.1 minutes) 3

Evidence Quality and Limitations

• The evidence supporting high-ratio transfusion in trauma comes from both observational studies and RCTs, though overall certainty is low to moderate 1
• Observational studies show larger mortality benefits but may be subject to survivorship bias 1
• RCTs show more modest benefits focused on reduced death from exsanguination rather than overall mortality 1
• There is insufficient evidence to recommend fixed high-ratio transfusion strategies for non-traumatic massive bleeding 1

Special Considerations

• Recent evidence suggests trauma-induced coagulopathy is multifactorial, involving hypoperfusion, factor consumption, and hyperfibrinolysis, not just dilution 4
• Standard venous thromboprophylaxis should be commenced as soon as possible after hemostasis is secured, as patients develop a prothrombotic state following massive hemorrhage 1
• There is insufficient evidence to make recommendations regarding the use of cryopreserved or cold-stored platelets in massive hemorrhage 1

Common Pitfalls

• Delaying initiation of the massive transfusion protocol can worsen outcomes 5
• Focusing solely on RBC transfusion without addressing coagulopathy 4
• Using O negative blood unnecessarily when group-specific blood would suffice 1
• Failing to transition from protocol-based to patient-specific transfusion as laboratory results become available 4
• Not addressing other aspects of resuscitation such as temperature control, acid-base balance, and calcium levels 4