title: Endotracheal temperature and humidity in laryngectomized patients in a warm and dry environment and the effect of a heat and moisture exchanger.
abstract: BACKGROUND
  This study was designed to assess endotracheal climate in laryngectomized patients in a warm and dry environment and the effects of a heat and moisture exchanger (HME).
  
  
  METHODS
  Endotracheal temperature and humidity were measured in 11 laryngectomized patients with a regularly used HME (Provox Normal HME; R-HME), an HME with antimicrobial filter (Provox Micron HME; F-HME), and without HME (open stoma). Measurements were performed at 32°C, 34°C, and 38°C (<25% relative humidity).
  
  
  RESULTS
  Both R-HME and F-HME increased end-inspiratory humidity (AH(insp)) equally (range, 3.4 to 5.6 mg H(2)O/L). The R-HME has a cooling effect on end-inspiratory temperature (T(insp)), which is similar for all tested environmental conditions (-3.8°C); F-HME decreases T(insp) less (range, -1.3 to -0.6°C).
  
  
  CONCLUSIONS
  In a warm and dry environment, both R- and F-HME significantly cool and humidify inspired air. Therefore, consistent use of an HME under these climate conditions is also probably clinically beneficial.
authors.affiliation: Department of Head and Neck Oncology and Surgery, The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands.
authors.forename: Renske J
authors.initials: RJ
authors.lastname: Scheenstra
authors.forename: Sara H
authors.initials: SH
authors.lastname: Muller
authors.forename: Frans J M
authors.initials: FJ
authors.lastname: Hilgers
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001831:Body Temperature / Q000502:physiology*; D045853:Exhalation / Q000502:physiology; D005260:Female; D006801:Humans; D006813:Humidity; D001239:Inhalation / Q000502:physiology; D007825:Laryngectomy; D008297:Male; D008875:Middle Aged; D012138:Respiratory Therapy / Q000295:instrumentation*; D013696:Temperature; D014132:Trachea / Q000502:physiology