title: Rewarming rates in urban patients with hypothermia: prediction of underlying infection.
abstract: BACKGROUND
  In the urban setting, hypothermia is commonly associated with illness or intoxication, with death often secondary to infection.
  
  
  OBJECTIVE
  To evaluate factors that affect the rewarming rate (RWR) and the ability of the RWR and other clinical markers to predict the presence or absence of underlying infection in an adult urban population.
  
  
  METHODS
  This was a prospective observational study of hypothermic patient visits to a large emergency department. Serial temperatures were obtained during rewarming to construct rewarming curves. Rewarming modalities selected by emergency physicians were correlated with admission temperatures. Univariate associates of RWR and infection were assessed.
  
  
  RESULTS
  The authors identified 96 patient visits. The median temperature was 89.5 degrees F (31.9 degrees C; range, 73.0 degrees F to 95.0 degrees F [22.8 degrees C to 35.0 degrees C]). Thirteen patients had temperatures of < 80.0 degrees F (26.0 degrees C). Seven died within 14 hours of presentation; six, of infection. No patient experienced ventricular fibrillation. Potential candidate predictors of infection from a multivariate analysis were a RWR of < 1.80 degrees F (1.0 degrees C) per hour and a serum albumin of < 2.7 g/dL. Rapid rewarming was associated with the absence of infection and a temperature below 86.0 degrees F (30.0 degrees C). In patients without significant underlying illness, rewarming rates appeared to be independent of the modality of rewarming.
  
  
  CONCLUSIONS
  Rewarming rates reflect intrinsic capacity for thermogenesis. Increased RWRs were associated with the absence of infection. The achievement of normothermia did not prevent death in infected patients. Initiation of invasive rewarming in urban patients with hypothermia who have not had hypothermic cardiac arrest may be unwarranted. Management of this population should emphasize support, detection, and treatment of underlying illness.
authors.affiliation: Division of Emergency Medicine/Department of Surgery, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8579, USA. kathleen.delaney@utsouthwestern.edu
authors.forename: Kathleen A
authors.initials: KA
authors.lastname: Delaney
authors.forename: Susi U
authors.initials: SU
authors.lastname: Vassallo
authors.forename: Gregory L
authors.initials: GL
authors.lastname: Larkin
authors.forename: Lewis R
authors.initials: LR
authors.lastname: Goldfrank
mesh_terms: D017677:Age Distribution; D000418:Albumins / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D001794:Blood Pressure; D001831:Body Temperature; D015331:Cohort Studies; D015897:Comorbidity; D005260:Female; D006801:Humans; D007003:Hypoglycemia / Q000453:epidemiology; D007035:Hypothermia / Q000453:epidemiology* / Q000628:therapy*; D007239:Infections / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009519:New York City / Q000453:epidemiology; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011674:Pulse; D017694:Rewarming / Q000379:methods / Q000706:statistics & numerical data*; D012768:Shivering; D019966:Substance-Related Disorders / Q000453:epidemiology; D016019:Survival Analysis
chemical_list: D000418:Albumins; D015415:Biomarkers