Massive Blood Transfusion

Aka: Massive Blood Transfusion, Massive Transfusion, Dilutional Coagulopathy

1. See Also
   1. Hemorrhage Management
2. Indications
   1. ABC Hemorrhage Score of 2 or more OR
   2. Trauma with Hemorrhage requiring transfusion of Packed Red Blood Cells that replace >50% of Blood Volume
      1. More than 50% of Blood Volume in 4 hours (4-6 units replaced in an average adult)
      2. More than 100% of Blood Volume in 24 hours (8-12 units replaced in an average adult)
   3. Calculating total Blood Volume in units
      1. Blood Volume is 70 ml/kg in adults, 80 ml/kg in children, 100 ml/kg in infants
      2. One unit or pint of blood is 450 ml
      3. Blood Volume in Units = wtKg/6.4 in adults, wtKg/5,6 in children, wtKg/4.5 in neonates
   4. Critical Administration Threshold (CAT)
      1. Three or more units pRBC transfused within 60 minutes
      2. CAT+1: 3 units in 1 hour
      3. CAT+2: A second set of 3 units pRBC transfused in 1 hour
      4. CAT+3: A third set of 3 units pRBC transfused in 1 hour
      5. CAT+4: A fourth set of 3 units pRBC transfused in 1 hour
      6. Savage (2015) J Trauma Acute Care Surg 78(2):224-9 +PMID: 25757105 [PubMed]
3. Mechanism
   1. Dilutional Coagulopathy
      1. Coagulopathy develops with Massive Blood Transfusion (dilution of Coagulation Factors)
   2. FFP helps treat the Coagulopathy by replacing Fibrinogen, C1 esterase, antiplasmins and other factors
   3. Thromboelastography (TEG)
      1. Measures overall coagulation efficiency and can identify the severity of coagulation defects
      2. Typically limited to large Trauma Centers
4. Protocol: Primary 1:1:1 replacement
   1. Notify the blood bank early regarding need for Massive Transfusion protocol
   2. Red Blood Cell replacement remain the first priority
      1. Continue Blood Transfusion until bleeding is controlled or patient becomes hemodynamically stable
   3. Ratio of 1:1:1 of platelets : plasma : Red Blood Cells is preferred (decreased mortality compared with 1:1:2)
      1. Replace 1 unit of Fresh Frozen Plasma for every 1 unit of Packed Red Blood Cells (pRBC)
         1. Typically the limiting factor (insufficient supply)
         2. Ideal universal donor is AB Plasma, which is in short supply
      2. Replace 1 unit of apheresis platelets for every 6-8 units of Packed Red Blood Cells
         1. Each unit of apheresis platelets is equivalent to prior platelet 6-pack
5. Protocol: Other Measures
   1. Consider Cryoprecipitate
      1. Cryoprecipitate primarily replaces Fibrinogen (but also Von Willebrand Factor, Factor VIII)
      2. If bleeding continues despite 1:1:1 replacement, obtain a Fibrinogen level
         1. Transfuse Cryoprecipitate if Fibrinogen level <150 mg/dl
         2. One unit Cryoprecipitate per 5 kg wtKg raises Fibrinogen 100 mg/dl
   2. Consider Prothrombin Complex Concentrate (PCC) 1-2 doses
      1. Do not use beyond 6-7 hours from bleeding onset (due to increased bleeding risk)
      2. Consider if bleeding is refractory to multiple units with 1:1:1 replacement
   3. Consider Tranexamic Acid
      1. Give within first 3 hours of injury
         1. Avoid if more than 3 hours after injury (no benefit, and possible harm)
6. Precautions
   1. Avoid Hypothermia (worsens Coagulopathy when <35 C, and especially when <32 C)
      1. Keep Body Temperature >35 C
      2. Warm blood (each unit may lower Body Temperature 0.25 C)
      3. Consider Bair Hugger
7. Complications
   1. Dilutional Coagulopathy
   2. Hypothermia
   3. Hyperkalemia
   4. Hypocalcemia
   5. Metabolic Acidosis
8. References
   1. Orman and DeLoughery in Herbert (2017) EM:Rap 17(4): 5-6
   2. Holcomb (2012) Arch Surg 15:1-10 [PubMed]
   3. Holcomb (2015) JAMA 313(5): 471-82 +PMID:25647203 [PubMed]