title: A randomized trial of prewarming on patient satisfaction and thermal comfort in outpatient surgery.
abstract: OBJECTIVE
  To test the primary hypothesis that forced-air prewarming improves patient satisfaction after outpatient surgery and to evaluate the effect on core temperature and thermal comfort.
  
  
  METHODS
  Prospective randomized controlled trial.
  
  
  METHODS
  Preoperative area, operating room, and postanesthesia care unit.
  
  
  METHODS
  A total of 115 patients aged 18 to 75 years with American Society of Anesthesiologists status <4 and body mass index of 15 to 36kg/m(2) who were undergoing outpatient surgery (duration <4 hours).
  
  
  METHODS
  Patients were randomized to active prewarming with a Mistral-Air warming system initially set to 43°C or no active prewarming. All patients were warmed intraoperatively.
  
  
  METHODS
  Demographic and morphometric characteristics, perioperative core temperature, ambient temperature, EVAN-G satisfaction score, thermal comfort via visual analog scales.
  
  
  RESULTS
  Data from 102 patients were included in the final analysis. Prewarming did not significantly reduce redistribution hypothermia, with prewarmed minus not prewarmed core temperature differing by only 0.18°C (95% confidence interval [CI], -0.001 to 0.37) during the initial hour of anesthesia (P=.052). Prewarming increased the mean EVAN-G satisfaction score, although not significantly, with an overall difference (prewarmed minus not prewarmed) of 5.6 (95% CI, -0.9 to 12.2; P=.09). Prewarming increased thermal comfort, with an overall difference of 6.6 mm (95% CI, 1.0-12.9; P=.02).
  
  
  CONCLUSIONS
  Active prewarming increased thermal comfort but did not significantly reduce redistribution hypothermia or improve postoperative patient satisfaction.
authors.affiliation: Clinical Research Fellow, Department of Outcomes Research, Anesthesiology Institute, Cleveland Clinic, Cleveland, OH.
authors.forename: Zohaib
authors.initials: Z
authors.lastname: Akhtar
authors.affiliation: Research Staff, Department of Outcomes Research, Anesthesiology Institute, Cleveland Clinic, Cleveland, OH.
authors.forename: Brian D
authors.initials: BD
authors.lastname: Hesler
authors.affiliation: Research Assistant, Department of Outcomes Research, Anesthesiology Institute, Cleveland Clinic, Cleveland, OH.
authors.forename: Alexa N
authors.initials: AN
authors.lastname: Fiffick
authors.affiliation: Associate Staff of Biostatistics, Departments of Quantitative Health Sciences, Lerner Research Institute and Outcomes Research, Anesthesiology Institute, Cleveland Clinic, Cleveland, OH.
authors.forename: Edward J
authors.initials: EJ
authors.lastname: Mascha
authors.affiliation: Professor and Chair, Department of Outcomes Research, Anesthesiology Institute, Cleveland Clinic, Cleveland, OH.
authors.forename: Daniel I
authors.initials: DI
authors.lastname: Sessler
authors.affiliation: Professor and Vice-Chair, Department of Outcomes Research, Anesthesiology Institute, Cleveland Clinic, Cleveland, OH; Chair, Department of General Anesthesia, Anesthesiology Institute, Cleveland Clinic, Cleveland, OH.
authors.forename: Andrea
authors.initials: A
authors.lastname: Kurz
authors.affiliation: Clinical Associate Professor and Chair, Fairview Hospital, Anesthesiology Institute, Cleveland Clinic, Cleveland, OH.
authors.forename: Sabry
authors.initials: S
authors.lastname: Ayad
authors.affiliation: Associate Professor, Department of Outcomes Research, Anesthesiology Institute, Cleveland Clinic, Cleveland, OH. Electronic address: saagerl@ccf.org.
authors.forename: Leif
authors.initials: L
authors.lastname: Saager
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000556:Ambulatory Surgical Procedures / Q000379:methods*; D001831:Body Temperature; D005260:Female; D006801:Humans; D007036:Hypothermia, Induced / Q000379:methods; D007430:Intraoperative Care; D008297:Male; D008875:Middle Aged; D000070659:Patient Comfort; D017060:Patient Satisfaction; D011446:Prospective Studies; D017694:Rewarming / Q000379:methods*; D016896:Treatment Outcome; D055815:Young Adult
keywords: Anesthesia; Normothermia; Outpatient surgery; Patient satisfaction; Prewarming; Thermoregulation