Defining Ultra-Massive Transfusion through a Systematic Review.

ABSTRACT

Background: Despite the widespread use of ultra-massive transfusion (UMT) as an intervention for trauma patients in hemorrhagic shock, no standard definition exists. We performed a systematic review to determine a consensus definition for UMT. Methods: A search was performed from 1979-2022. The authors screened studies defining UMT and associated outcomes as defined by our prespecified PICO questions. The PRISMA guidelines were used. Results: 1662 articles met criteria for eligibility assessment, 17 for full-text review and eight for data extraction. Only two studies demonstrated a consensus definition of UMT, which used ≥20 units of red blood cell product within 24hrs. Parameters associated with increased mortality included lower blood pressure, lower pulse and lower Glasgow Coma Score at the time of presentation and a higher injury severity score and undergoing a resuscitative thoracotomy. Conclusions: The absence of a consensus definition for UMT raises challenges from clinical, research and ethical perspectives. Based on our findings, the authors advocate for the feasibility of standardizing the definition of UMT as ≥20 units of red blood cell product within 24hrs.