title: Optimizing outcomes in damage control resuscitation: identifying blood product ratios associated with improved survival.
abstract: BACKGROUND
  Despite recent attention and impressive results with damage control resuscitation, the appropriate ratio of blood products to be transfused has yet to be defined. The purpose of this study was to evaluate whether suggested blood product ratios yield superior survival rates.
  
  
  METHODS
  After IRB approval, a retrospective evaluation was performed on all trauma exsanguination protocol (TEP, n = 118) activations from February 1, 2006 to July 31, 2007. A comparison cohort (pre-TEP, n = 140) was selected from all trauma admissions between August 1, 2004 and January 31, 2006 that (1) underwent immediate surgery by the trauma team and (2) received greater than 10 units of PRBC in the first 24 hours. We then compared those who received FFP:RBC (2:3) and platelet:RBC (1:5) ratios with those who did not reach these ratios. Multivariate analysis was performed for independent predictors of mortality.
  
  
  RESULTS
  A total of 259 patients were available for study. Patients receiving FFP:RBC at a ratio of 2:3 or greater (n = 64) had a significant reduction in 30-day mortality compared with those who received less than a 2:3 ratio (n = 195); 41% versus 62%, p = 0.008. Patients receiving platelets:RBC at a ratio of 1:5 or greater (n = 63) had a lower 30-day mortality when compared with those with who received less than this ratio (n = 196); (38% vs. 61%, p = 0.001). Regression model demonstrated that a ratio of FFP to PRBC is an independent predictor of 30-day mortality, controlling for age and TRISS (OR 1.78, 95% CI 1.01-3.14).
  
  
  CONCLUSIONS
  Increased FFP:PRBC and PLT:PRBC ratios during a period of massive transfusion improved survival after major trauma. Massive transfusion protocols should be designed to achieve these ratios to provide maximal benefit.
authors.affiliation: Department of General Surgery, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.
authors.forename: Oliver L
authors.initials: OL
authors.lastname: Gunter
authors.forename: Brigham K
authors.initials: BK
authors.lastname: Au
authors.forename: James M
authors.initials: JM
authors.lastname: Isbell
authors.forename: Nathan T
authors.initials: NT
authors.lastname: Mowery
authors.forename: Pampee P
authors.initials: PP
authors.lastname: Young
authors.forename: Bryan A
authors.initials: BA
authors.lastname: Cotton
mesh_terms: D000328:Adult; D001772:Blood Cell Count; D016913:Blood Component Transfusion / Q000379:methods*; D002985:Clinical Protocols; D015331:Cohort Studies; D003422:Critical Care; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012771:Shock, Hemorrhagic / Q000209:etiology / Q000401:mortality* / Q000628:therapy*; D015996:Survival Rate; D016896:Treatment Outcome; D014947:Wounds and Injuries / Q000150:complications* / Q000401:mortality* / Q000628:therapy