title: The effect of preheated versus room-temperature skin disinfection on bacterial colonization during pacemaker device implantation: a randomized controlled non-inferiority trial.
abstract: BACKGROUND
  In clinical practice, patients who are awake often comment that cold surgical skin disinfectant is unpleasant. This is not only a problem of patients' experience; heat loss during the disinfection process is a problem that can result in hypothermia. Evidence for the efficacy of preheated disinfection is scarce. We tested whether preheated skin disinfectant was non-inferior to room-temperature skin disinfectant on reducing bacterial colonization during pacemaker implantation.
  
  
  METHODS
  This randomized, controlled, non-inferiority trial included 220 patients allocated to skin disinfection with preheated (36 °C) or room-temperature (20 °C) chlorhexidine solution in 70 % ethanol. Cultures were obtained by swabbing at 4 time-points; 1) before skin disinfection (skin surface), 2) after skin disinfection (skin surface), 3) after the incision (subcutaneously in the wound), and 4) before suturing (subcutaneously in the wound).
  
  
  RESULTS
  The absolute difference in growth between patients treated with preheated versus room-temperature skin disinfectant was zero (90 % CI -0.101 to 0.101; preheated: 30 of 105 [28.6 %] vs. room-temperature: 32 of 112 [28.6 %]). The pre-specified margin for statistical non-inferiority in the protocol was set at 10 % for the preheated disinfectant. There were no significant differences between groups regarding SSIs three month postoperatively, which occurred in 0.9 % (1 of 108) treated with preheated and 1.8 % (2 of 112) treated with room-temperature skin disinfectant.
  
  
  CONCLUSIONS
  Preheated skin disinfection is non-inferior to room-temperature disinfection in bacterial reduction. We therefore suggest that preheated skin disinfection become routine in clean surgery.
  
  
  BACKGROUND
  The study is registered at ClinicalTrials.gov (NCTO2260479).
authors.affiliation: Faculty of Medicine and Health, School of Health Sciences, Örebro, SE 701 82 Sweden ; Department of Cardiothoracic surgery and Vascular surgery, University hospital in Örebro, Grevrosengatan, 701 85 Örebro, Sweden.
authors.forename: Camilla
authors.initials: C
authors.lastname: Wistrand
authors.affiliation: Faculty of Medicine and Health, School of Medical Sciences, Örebro, SE 701 82 Sweden.
authors.forename: Bo
authors.initials: B
authors.lastname: Söderquist
authors.affiliation: Clinical Epidemiology and Biostatistics, Faculty of Medicine and Health, Örebro University, Örebro, SE 701 82 Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Magnusson
authors.affiliation: Faculty of Medicine and Health, School of Health Sciences, Örebro, SE 701 82 Sweden.
authors.forename: Ulrica
authors.initials: U
authors.lastname: Nilsson
keywords: Bacterial growth; Non-inferiority; Perioperative; Skin disinfection