The patient should have blood testing upon initiation of the MHP and then repeated at least hourly thereafter.

• Laboratory testing can help identify patients receiving oral anticoagulant therapy and in need of reversal, assess quality of resuscitation, and guide blood component administration
• Blood component therapy is administered at a 2:1 ratio (RBC to plasma) and then switched to goal-directed as soon as practical
• Recommended tests include hemoglobin and platelet count, coagulation tests, and markers of organ injury and/or shock
• Occasionally, blood testing may need to be done more frequently, based on clinical situation

• Recommended blood test bundle includes:
  • ABO blood group, antibody screen, and ABO verification
  • Complete Blood Count (CBC), International Normalized Ratio (INR), activated Partial Thromboplastin Time (aPTT), fibrinogen, Arterial Blood Gas (ABG), ionized calcium, lactate, and electrolytes
    • Note: aPTT does not need to be repeated as long as first PTT is concordant with the baseline INR
  • If available, rotational thromboelastometry (ROTEM) or thromboelastography (TEG) may also be useful
• Biochemical tests (e.g., potassium, calcium, and pH) may indicate potential complications from massive transfusion or inadequate resuscitation of the patient in hemorrhagic shock
• Lactate measurements are predictive of mortality, although the role of serial measurements in improving patient outcomes has not been confirmed in clinical trials
• Laboratory should call all critical results to the bedside team

Having access to the most up-to-date laboratory results allows for more effective resuscitation and may improve patient outcomes.

Ensure correct blood work is drawn at the beginning of MHP and repeated hourly.

References:

1. Bawazeer M, Ahmed N, Izadi H, et al. Compliance With a Massive Transfusion Protocol (MTP) Impacts Patient Outcome. Injury. 2015;46(1):21-28.
2. Callum JL, Yeh CH, Petrosoniak A, et al. A Regional Massive Hemorrhage Protocol Developed Through a Modified Delphi Technique. CMAJ Open. 2019;7(3):e546-561.
3. Chandler WL, Ferrell C, Trimble S, et al. Development of a Rapid Emergency Hemorrhage Panel. Transfusion. 2010;50(12):2547-2552.
4. Young PP, Cotton BA, Goodnough LT. Massive Transfusion Protocols for Patients With Substantial Hemorrhage. Transfus Med Rev. 2011;25(4):293-303.