title: Prospective evaluation of ambient operating room temperature on the core temperature of injured patients undergoing emergent surgery.
abstract: BACKGROUND
  Although uncomfortable for the operating team, trauma operating room (OR) temperatures have traditionally been kept warm in an attempt to mitigate intraoperative heat loss. The purpose of this study was to examine how ambient OR temperatures impact core temperature in patients undergoing emergent surgery for trauma.
  
  
  METHODS
  Injured adult patients requiring emergent surgery at a Level 1 trauma center were prospectively enrolled between July 2008 and January 2010. Standardized warming measures were used for all patients. Ambient OR temperature was recorded in 5-minute intervals with the Fourier Microlog EC600 temperature data logger. Intraoperative core patient temperatures were compared with ambient OR temperature. Patients experiencing intraoperative core temperature decreases were compared with those who did not, to examine the impact of ambient temperature changes on the risk of perioperative hypothermia.
  
  
  RESULTS
  During the 18-month study period, 118 patients requiring emergent surgery (73% laparotomy, 5% thoracotomy, 7% combined, 15% other) were enrolled. Incidence of hypothermia (<35°C) at admission to the OR was 29.7%. Crude mortality increased as the final patient core temperature achieved in the OR decreased (4.2% for temperatures >35°C and as high as 50% for temperatures ≤32°C). Overall, core temperature decreased in 46 patients (39.0%) but remained stable or increased by the end of the procedure in 72 (61%). There were no significant differences in the admission temperature, clinical demographics, or volume of fluids and blood products between the two groups. In a forward logistic regression analysis, a lower ambient OR temperature was not associated with a drop in the patient's core temperature.
  
  
  CONCLUSIONS
  In this prospective study, the ambient OR temperature did not affect the core temperature of injured patients undergoing emergent surgery.
  
  
  METHODS
  Prognostic study, level III; therapeutic study, level IV.
authors.affiliation: Division of Trauma Surgery and Surgical Critical Care, Los Angeles County Medical Center, University of Southern California, Los Angeles, California, USA. kinaba@surgery.usc.edu
authors.forename: Kenji
authors.initials: K
authors.lastname: Inaba
authors.forename: Regan
authors.initials: R
authors.lastname: Berg
authors.forename: Galinos
authors.initials: G
authors.lastname: Barmparas
authors.forename: Peter
authors.initials: P
authors.lastname: Rhee
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Jurkovich
authors.forename: Gustavo
authors.initials: G
authors.lastname: Recinos
authors.forename: Pedro G
authors.initials: PG
authors.lastname: Teixeira
authors.forename: Demetrios
authors.initials: D
authors.lastname: Demetriades
mesh_terms: D000328:Adult; D001831:Body Temperature / Q000502:physiology; D005260:Female; D006801:Humans; D007035:Hypothermia / Q000209:etiology; D007432:Intraoperative Period; D008297:Male; D009873:Operating Rooms; D011184:Postoperative Period; D011446:Prospective Studies; D013696:Temperature; D014193:Trauma Centers; D014947:Wounds and Injuries / Q000503:physiopathology / Q000601:surgery*