Hypothermia is associated with poor outcomes after injury. The relationship between hypothermia during contemporary large volume resuscitation and blood product consumption is unknown. We evaluated this association, and the predictive value of hypothermia on mortality.
Patients predicted to receive massive transfusion at 12 level 1 trauma centers were randomized in the Pragmatic Randomized Optimal Platelet and Plasma Ratios (PROPPR) trial and were grouped into those who were hypothermic (<36°C) or normothermic (36–38.5°C) within the first 6 hours of emergency department arrival. The impact of hypothermia or normothermia on the volume of blood product required during the first 24 hours was determined via negative binomial regression, adjusting for treatment arm, injury severity score, mechanism, demographics, pre–emergency department fluid volume, blood administered before becoming hypothermic, pulse and systolic blood pressure on arrival, and the time exposed to hypothermic or normothermic temperatures.
Of 680 patients, 590 had a temperature measured during the first 6 hours in hospital, and 399 experienced hypothermia. The mean number of red blood cell (RBC) units given to all patients in the first 24 hours of admission was 8.8 (95% confidence interval [CI], 7.9–9.6). In multivariable analysis, every 1°C decrease in temperature below 36.0°C was associated with a 10% increase (incidence rate ratio, 0.90; 95% CI, 0.89–0.92; p < 0.00) in consumption of RBCs during the first 24 hours of admission. There was no association between RBC administration and a temperature above 36°C. Hypothermia on arrival was an independent predictor of mortality, with an adjusted odds ratio of 2.7 (95% CI, 1.7–4.5; p < 0.00) for 24-hour mortality and 1.8 (95% CI, 1.3–2.4; p < 0.00) for 30-day mortality.
Hypothermia is associated with increase in blood product consumption and mortality. These findings support the maintenance of normothermia in trauma patients and suggest that further investigation on the impact of cooling or rewarming during massive transfusion is warranted.
Prognostic, level III.
From the Division of General Surgery (E.L.W.L.), Department of Surgery, University of Alberta, Edmonton, Alberta, Canada; Center for Translational Injury Research (E.E.F., J.H.), Division of Acute Care Surgery, Department of Surgery, Medical School, University of Texas Health Science Center, Houston, Texas; Division of Trauma (K.B.), Critical Care and Acute Care Surgery, School of Medicine, Oregon Health and Science University, Portland, Oregon; Division of Trauma and Critical Care (E.M.B.), Department of Surgery, School of Medicine, University of Washington, Seattle, Washington; Department of Surgery (M.C.), University of Colorado, Denver, Colorado; Center for Translational Injury Research (B.A.C.), Division of Acute Care Surgery, Department of Surgery, Medical School, University of Texas Health Science Center, Houston, Texas; Division of Trauma and Surgical Critical Care (T.C.T.C.F.), Department of Surgery, College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee; Division of Trauma (J.D.K.), Burns and Surgical Critical Care, Department of Surgery, School of Medicine, University of Alabama, Birmingham, Alabama; Division of Trauma (T.O.), Critical Care and Emergency Surgery, Department of Surgery, University of Arizona, Tucson, Arizona; Trauma and Acute Care Service (S.B.R.), St. Michael's Hospital, Toronto, Ontario, Canada; R Adams Crowley Shock Trauma Center (T.S.), University of Maryland, Baltimore, Maryland; Division of Trauma (M.A.S.), Critical Care and Acute Care Surgery, Department of Surgery, Oregon Health and Science University, Portland, Oregon; and Division of Trauma and Critical Care (K.I.), LAC+USC Medical Center, University of Southern California, Los Angeles, California.
Submitted: August 2, 2018, Accepted: October 2, 2018, Published online: November 15, 2018.
Address for reprints: Kenji Inaba, MD, Division of Trauma and Critical Care, LAC+USC Medical Center, University of Southern California, 2051 Marengo St, IPT, C5L100, Los Angeles, CA 90033; email: email@example.com.