Survival of trauma patients after massive red blood cell transfusion using a high or low red blood cell to plasma transfusion ratio*
Anita Rajasekhar, MD; Rob Gowing, MD, MSc; Ryan Zarychanski, MD, MSc; Donald M. Arnold, MD, MSc; Wendy Lim, MD, MSc; Mark A. Crowther, MD, MSc; Richard Lottenberg, MD
Objective: Early and aggressive treatment of trauma-associated coagulopathythrough transfusion of high plasma to packed red blood cell ratios is gaining favor. Whether this strategy is associated with improved survival is unclear. We performed a systematic review to determine whether higher plasma to packed red blood cell ratios compared with lower plasma to packed red blood cell ratios were associated with a survival advantage. Data Sources: We searched electronicdatabases MEDLINE, Embase, and Web of Science from 1950 to February 2010 for studies comparing mortality in massively transfused trauma cohorts receiving different plasma to packed red blood cell ratios. Study Selection: Two reviewers independently performed study selection. Discrepancies in study selection were resolved by discussion and consensus. Data Extraction: Two reviewers independently extracteddata from each study using a standardized form. Two authors independently assessed study quality using the Newcastle-Ottawa Scale. Data Synthesis: Eleven observational studies and no randomized controlled trials were identiﬁed. Three studies found a survival beneﬁt with a 1:1 plasma to packed red blood cell transfusion ratio compared with either higher or lower ratios. Six studies did not examinea 1:1 ratio but concluded that higher plasma to packed red blood cell ratios improved survival. Secondary outcomes, including multiorgan system failure, packed red blood cell transfusion, respiratory outcomes, and coagulation variables, did not uniformly favor 1:1 or higher plasma to packed red blood cell ratios. Conclusions: Methodological ﬂaws, including survival bias, and heterogeneity betweenstudies preclude statistical comparisons concerning the effects of a 1:1 plasma to packed red blood cell transfusion ratio. There is insufﬁcient evidence to support a survival advantage with a 1:1 plasma to packed red blood cell transfusion strategy. Randomized controlled trials evaluating safety and efﬁcacy are warranted before a high plasma to packed red blood cell transfusion ratio can berecommended. (Crit Care Med 2011; 39:1507–1513) KEY WORDS: trauma; massive transfusion; packed red blood cells; plasma; survival; ratio; systematic review
ncontrolled hemorrhage is the most common cause of preventable early death in both civilian and military trauma. Resuscitation with crystalloid ﬂuids and plasma-poor red cell concentrates can lead to dilutional coagulopathy, which is furtherexacerbated by hy-
*See also p. 1597. From the University of Florida (AR, RL), Gainesville, FL; and McMaster University (RG, DMA, WL, MAC), Hamilton, Ontario; and University of Manitoba (RZ), Winnipeg, Manitoba, Canada. Dr. Crowther holds a Career Investigator Award from the Heart and Stroke Foundation of Canada (Ottawa, Ontario, Canada). Dr. Arnold is supported by a New Investigator Award fromthe Canadian Institutes of Health Research (Ottawa, Ontario, Canada) in partnership with Hoffmann-LaRoche (Basel, Switzerland). The authors have not disclosed any potential conﬂicts of interest. Address requests for reprints to: Anita Rajasekhar, MD, Division of Hematology/Oncology, Department of Medicine, University of Florida, 1600 Southwest Archer Road, Gainesville, FL. E-mail:email@example.comﬂ.edu Copyright © 2011 by the Society of Critical Care Medicine and Lippincott Williams & Wilkins DOI: 10.1097/CCM.0b013e31820eb517
pothermia and acidosis that accompany severe injury and large-volume resuscitation (1). To mitigate resuscitationinduced coagulopathy, a transfusion strategy of early and increased plasma use has been proposed (2). Previous transfusion strategies in the setting...