II. Indications
- ABC Hemorrhage Score of 2 or more OR
- Hemorrhagic Shock with 2 or more risk factors as below (see Houston protocol below) OR
-
Trauma with Hemorrhage requiring Transfusion of Packed Red Blood Cells that replace >50% of Blood Volume
- More than 50% of Blood Volume in 4 hours (4-6 units replaced in an average adult)
- More than 100% of Blood Volume in 24 hours (8-12 units replaced in an average adult)
- Calculating total Blood Volume in units
- Blood Volume is 70 ml/kg in adults, 80 ml/kg in children, 100 ml/kg in infants
- One unit or pint of blood is 450 ml
- Blood Volume in Units = wtKg/6.4 in adults, wtKg/5.6 in children, wtKg/4.5 in neonates
- Critical Administration Threshold (CAT)
- Three or more units pRBC transfused within 60 minutes
- CAT+1: 3 units in 1 hour
- CAT+2: A second set of 3 units pRBC transfused in 1 hour
- CAT+3: A third set of 3 units pRBC transfused in 1 hour
- CAT+4: A fourth set of 3 units pRBC transfused in 1 hour
- Savage (2015) J Trauma Acute Care Surg 78(2):224-9 +PMID: 25757105 [PubMed]
III. Risk Factors: Predictors of Massive Blood Transfusion (MBT)
- Emergency department arrival Heart Rate >120
- Emergency department arrival Heart Rate <90 mmHg
- Positive FAST Exam
- Penetrating Trauma
- Uncrossed match blood use in the Emergency Department
IV. Diagnosis: Triggers for Massive Blood Transfusion (MBT)
-
Assessment of Blood Consumption Score
- Score >=2 predicts MBT in 40% of cases (100% if score of 4)
- Houston Protocol
- Two or more criteria suggest need for Massive Blood Transfusion
- Test Sensitivity: 86%
- PPV: 53%
- NPV: 96%
- Revised Assessment of Bleeding and Transfusion Score (RABT Score)
- Criteria
- Penetrating Injury
- Positive FAST
- Shock Index >1.0
- Pelvic Fracture
- Interpretation
- Total score >=2 predicts need for Massive Transfusion
- Criteria
V. Mechanism
- Dilutional Coagulopathy
- Coagulopathy develops with Massive Blood Transfusion (dilution of Coagulation Factors)
- FFP helps treat the Coagulopathy by replacing Fibrinogen, C1 esterase, antiplasmins and other factors
-
Thromboelastography (TEG or r-TEG)
- Measures overall coagulation efficiency and can identify the severity of coagulation defects
- Typically limited to large Trauma Centers
VI. Protocol: Primary 1:1:1 replacement
- Notify the blood bank early regarding need for Massive Transfusion Protocol
-
Red Blood Cell replacement remain the first priority
- Continue Blood Transfusion until bleeding is controlled or patient becomes hemodynamically stable
- Ratio of 1:1:1 of Platelets : plasma : Red Blood Cells is preferred (decreased mortality compared with 1:1:2)
- Replace 1 unit of Fresh Frozen Plasma for every 1 unit of Packed Red Blood Cells (pRBC)
- Typically the limiting factor (insufficient supply)
- Available in some centers as Jumbo Plasma (2 to 3 plasma units at 450 to 600 ml)
- Ideal universal donor is AB Plasma, which is in short supply
- Aim for balanced transfusion within 3 hours of start
- Replace 1 unit of apheresis Platelets for every 6-8 units of Packed Red Blood Cells
- Each unit of apheresis Platelets is equivalent to prior Platelet 6-pack
- Empiric Platelet Transfusion based on balanced ratio may result in worse outcomes
- Consider Platelet Transfusion when Platelet Count <50,000 (or 100,000 if Intracerebral Hemorrhage)
- Replace 1 unit of Fresh Frozen Plasma for every 1 unit of Packed Red Blood Cells (pRBC)
- Whole Blood Transfusion
- Universal donor Whole Blood Transfusion is FDA approved in Trauma and replaces 1:1:1 individual components
- Some major Trauma Centers stock universal donor whole blood for Massive Hemorrhage cases
- Associated with improved survival in severe Traumatic Hemorrhage
- References
- McCollum and Knight in Swadron (2022) EM:Rap 22(12): 8-9
- Shea (2020) Transfusion 60(suppl 3): S2-9 +PMID:32478896 [PubMed]
VII. Protocol: Other Measures
- Consider Cryoprecipitate (or Fibrinogen Concentrate)
- Cryoprecipitate primarily replaces Fibrinogen (but also Von Willebrand Factor, Factor VIII)
- Fibrinogen is also contained in FFP, which is the primary replacement unit in Massive Blood Transfusion
- Fibrinogen may also be given instead of Cryoprecipitate (and is preferred when available)
- Obtain Fibrinogen and r-TEG Level after 12 units pRBC, or bleeding despite 1:1:1 replacement
- Cryoprecipitate or Fibrinogen indications
- Fibrinogen level <150 - 180 mg/dl OR
- r-TEG Alpha angle shallow (e.g. <50 to 66 degrees)
- Cryoprecipitate dosing
- Typical adult dose 10 units
- One unit Cryoprecipitate per 5 kg wtKg raises Fibrinogen 100 mg/dl
- Fibrinogen Concentrate dosing
- Dose: 4 grams
- Preferred over Cryoprecipitate as raises Fibrinogen more predictably
- Consider empiric Fibrinogen administration (typically low at early stages of Hemorrhage)
- Cryoprecipitate primarily replaces Fibrinogen (but also Von Willebrand Factor, Factor VIII)
- Consider Prothrombin Complex Concentrate (PCC) 1-2 doses
- Do not use beyond 6-7 hours from bleeding onset (due to increased bleeding risk)
- Consider if bleeding is refractory to multiple units with 1:1:1 replacement
- Consider Tranexamic Acid
- Also consider in r-TEG LY30 >3%
- Give within first 3 hours of injury
- Avoid if more than 3 hours after injury (no benefit, and possible harm)
- Consider Calcium Supplementation
- Blood chelators (e.g. citrate) lower Serum Calcium and may alter hemodynamics
- Give 1 g Calcium Chloride (or 2 to 3 g Calcium Gluconate) at start of Massive Transfusion Protocol (or after third unit)
- Give 1 g Calcium Chloride (or 2 to 3 g Calcium Gluconate) for every 3 to 6 units of transfused blood
- Weingart and Swaminathan in Swadron (2022) EM:Rap 22(7): 2-3
VIII. Precautions
- Avoid Hypothermia (worsens Coagulopathy when <35 C, and especially when <32 C)
- Keep Body Temperature >35 C
- Warm blood (each unit may lower Body Temperature 0.25 C)
- Consider Bair Hugger
- Avoid excessive crystalloid (NS, LR)
- Prevent acidosis
IX. Complications
- Dilutional Coagulopathy
- Hypothermia
- Hyperkalemia
- Hypocalcemia
- Metabolic Acidosis
X. References
- Orman and DeLoughery in Herbert (2017) EM:Rap 17(4): 5-6
- Freeman and Bourland (2021) Crit Dec Emerg Med 35(12): 3-11
- Petrosoniak and Swaminathan (2022) EM:Rap 22(11): 5-7
- Holcomb (2012) Arch Surg 15:1-10 [PubMed]
- Holcomb (2015) JAMA 313(5): 471-82 +PMID:25647203 [PubMed]