title: Heat and moisture exchanger use reduces in-hospital complications following total laryngectomy: a case-control study.
abstract: BACKGROUND
  Total laryngectomy (TL) is an appropriate oncologic operation for many patients with laryngeal cancer delivering excellent oncologic outcomes, however it remains beset with significant functional consequences. Following TL, the upper and lower airways are permanently disconnected, which causes unfiltered, cold air with reduced humidity to enter the tracheobronchial tree, resulting in mucus overproduction and an increase in the viscosity of the mucus. In response to this, Heat and moisture exchangers were developed to compensate for the lost functions of the upper respiratory tract and their effect on the patients' respiratory performance in addition to their quality of life.
  
  
  METHODS
  The case records of 48 patients undergoing total laryngectomy were reviewed and data concerning demographics, surgical details, post-operative care requirements and adverse events was retrieved. Post hoc analysis of the case patients was undertaken to identify any benefit of using a heat and moisture exchanger (HME) system with particular reference to post-operative respiratory outcomes.
  
  
  RESULTS
  There was no significant difference between case and control subjects based on demographics, extent of surgery or need for flap repair. 16 patients had used a HME and 32 patients had used external humidification (EH). Of those experiencing mucous plugging, only 3/24 (12.5 %) had used a HME system, in contrast to 21/24 (87.5 %) who used EH (Chi square = 9.375, p = 0.002). The odds ratio of having an adverse event if not using HME was 8.27 (CI = 1.94 - 35.71). Use of HME also significantly reduced the number of days requiring physiotherapy (1.75 days vs. 3.20 days, p = 0.034).
  
  
  CONCLUSIONS
  Use of an HME system can reduce in-hospital complications, in particular episodes of mucus plugging, and post-operative care requirements. Furthermore, there is a cost benefit to using HME systems that warrants more widespread introduction of these devices in head and neck surgery centers.
authors.affiliation: Department of Otolaryngology Head and Neck Surgery, University of Adelaide, c/o Royal Adelaide Hospital, North Terrace, Adelaide, SA 5000, Australia.
authors.forename: A
authors.initials: A
authors.lastname: Foreman
authors.affiliation: Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Suite M1 102, Toronto, ON, M4N 3 M5, Canada.
authors.forename: R J
authors.initials: RJ
authors.lastname: De Santis
authors.affiliation: Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Suite M1 102, Toronto, ON, M4N 3 M5, Canada.
authors.forename: F
authors.initials: F
authors.lastname: Sultanov
authors.affiliation: Department of Otolaryngology - Head & Neck Surgery, University of Toronto, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Suite M1 102, Toronto, ON, M4N 3 M5, Canada.
authors.forename: D J
authors.initials: DJ
authors.lastname: Enepekides
authors.affiliation: Department of Otolaryngology - Head & Neck Surgery, University of Toronto, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Suite M1 102, Toronto, ON, M4N 3 M5, Canada. kevin.higgins@sunnybrook.ca.
authors.forename: K M
authors.initials: KM
authors.lastname: Higgins
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D005260:Female; D006361:Heating / Q000295:instrumentation; D006358:Hot Temperature; D006801:Humans; D006813:Humidity; D007825:Laryngectomy / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D011182:Postoperative Care / Q000295:instrumentation*; D011183:Postoperative Complications / Q000517:prevention & control*
keywords: Complications; HME; Heat moisture exchanger; Laryngectomy; Mucus plugging