title: A comparison of prehospital lactate and systolic blood pressure for predicting the need for resuscitative care in trauma transported by ground.
abstract: BACKGROUND
  Reliance on prehospital trauma triage guidelines misses patients with serious injury. Lactate is a biomarker capable of identifying high-risk trauma patients. Our objective was to compare prehospital point-of-care lactate (P-LAC) with systolic blood pressure (SBP) for predicting the need for resuscitative care (RC) in trauma patients transported by ground emergency medical services.
  
  
  METHODS
  This is a prospective observational study at nine sites within the Resuscitation Outcomes Consortium conducted from March 2011 to August 2012. Lactate was measured on patients with a prehospital SBP of 100 mm Hg or less who were transported by emergency medical services to a Level I or II trauma center. Patients were followed up for the need for RC, defined as any of the following within 6 hours of emergency department arrival: blood transfusion of 5 U or greater; intervention for hemorrhage including thoracotomy, laparotomy, pelvic fixation, or interventional radiology embolization; or death.
  
  
  RESULTS
  A total of 387 patients had a lactate value and presented with SBP between 71 mm Hg and 100 mm Hg, and 70 (18%) required RC. With the use of a P-LAC decision rule (≥2.5 mmol/L) that yielded the same specificity as that of SBP of 90 mm Hg or less (48%), the observed sensitivities for RC were 93% (95% confidence interval [CI], 84-98%) for P-LAC of 2.5 mmol/L or greater and 67% (95% CI, 55-78%) for SBP of 90 mm Hg or less (McNemar's test, p < 0.001). P-LAC has an estimated area under the curve of 0.78 (95% CI, 0.73-0.83), which is statistically superior to that of SBP (0.59; 95% CI, 0.53-0.66) and shock index (heart rate / SBP) (0.66; 95% CI, 0.60-0.74).
  
  
  CONCLUSIONS
  P-LAC obtained at the scene is associated with the need for RC. P-LAC is superior to other early surrogates for hypoperfusion (SBP and shock index) in predicting the need for RC in trauma patients with 70 mm Hg < SBP ≤ 100 mm Hg.
  
  
  METHODS
  Prognostic study, level II.
authors.affiliation: From the Department of Emergency Medicine (F.X.G.), University of Pittsburgh, Pittsburgh, Pennsylvania; Departments of Surgery (E.M.B.) and Biostatistics (E.N.M.), and Clinical Trials Center (J.L.P.), University of Washington, Seattle; Department of Surgery (K.J.B.), Medical College of Wisconsin, Milwaukee; Department of Emergency Medicine (M.D.), Emergency Medicine, Surgery and Public Health and Preventive Medicine (C.N.), Oregon Health and Science University, Portland, Oregon; Department of Surgery (J.D.K.), University of Alabama, Birmingham; Department of Surgery (M.S., R.C.), University of California, San Diego, California; Department of Surgery (T.C.F.), University of Tennessee, Memphis, Tennessee; National Heart, Lung, and Blood Institute (D.E.), National Institutes of Health, Bethesda, Maryland; and American College of Surgeons (D.B.H.), Chicago, Illinois.
authors.forename: Francis X
authors.initials: FX
authors.lastname: Guyette
authors.forename: Eric N
authors.initials: EN
authors.lastname: Meier
authors.forename: Craig
authors.initials: C
authors.lastname: Newgard
authors.forename: Barbara
authors.initials: B
authors.lastname: McKnight
authors.forename: Mohamud
authors.initials: M
authors.lastname: Daya
authors.forename: Eileen M
authors.initials: EM
authors.lastname: Bulger
authors.forename: Judy L
authors.initials: JL
authors.lastname: Powell
authors.forename: Karen J
authors.initials: KJ
authors.lastname: Brasel
authors.forename: Jeffery D
authors.initials: JD
authors.lastname: Kerby
authors.forename: Debra
authors.initials: D
authors.lastname: Egan
authors.forename: Michael
authors.initials: M
authors.lastname: Sise
authors.forename: Raul
authors.initials: R
authors.lastname: Coimbra
authors.forename: Timothy C
authors.initials: TC
authors.lastname: Fabian
authors.forename: David B
authors.initials: DB
authors.lastname: Hoyt
mesh_terms: D000328:Adult; D000552:Ambulances; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure / Q000502:physiology*; D005260:Female; D006801:Humans; D007773:Lactates / Q000097:blood*; D008297:Male; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D012151:Resuscitation / Q000379:methods*; D012680:Sensitivity and Specificity; D013599:Systole / Q000502:physiology*; D014193:Trauma Centers; D014218:Triage; D014947:Wounds and Injuries / Q000628:therapy*
chemical_list: D015415:Biomarkers; D007773:Lactates