title: Piloting a novel porcine model for endolaryngeal injury following prolonged intubation.
abstract: OBJECTIVE
  (1) To develop a practical animal model of endolaryngeal damage secondary to prolonged endotracheal intubation. (2) To demonstrate the contribution of chronic hypoxia to laryngeal injury in the context of this model.
  
  
  METHODS
  Four Sus scrofa piglets were anaesthetized and intubated for 24h. Two animals were maintained in a state of constant hypoxia (pO(2)<60 mmHg) while two others were ventilated with 100% oxygen. Prior to sacrifice, fluorescein dye was infused intravenously to highlight areas of hypoperfusion. The larynx and trachea were then harvested for gross and histological examination.
  
  
  RESULTS
  All four specimens demonstrated areas of edema, erythema, and ulceration on gross examination. Areas of significant histological inflammation, ulceration, and necrosis involved tube-mucosa contact, in particular, the arytenoids, the interarytenoid area, and the subglottis.
  
  
  CONCLUSIONS
  This animal model represents a practical and novel means for the investigation and treatment of laryngeal injury secondary to prolonged endotracheal intubation. Significant injury to the endolarynx was evident after only 24h of intubation and the injury involved similar areas within the larynx as described in human studies. Although clinical experience suggests that chronic hypoxia is a risk factor for endolaryngeal injury, this model did not provide experimental evidence to support this observation, most likely due to the small study size.
authors.affiliation: Department of Otolaryngology Head & Neck Surgery, The Hospital for Sick Children, 555 University Avenue, The University of Toronto, Toronto, Ontario, Canada M5G 1X8.
authors.forename: Manish D
authors.initials: MD
authors.lastname: Shah
authors.forename: Lily H P
authors.initials: LH
authors.lastname: Nguyen
authors.forename: Paolo
authors.initials: P
authors.lastname: Campisi
authors.forename: Adrian
authors.initials: A
authors.lastname: James
authors.forename: Glenn P
authors.initials: GP
authors.lastname: Taylor
authors.forename: Vito
authors.initials: V
authors.lastname: Forte
mesh_terms: D000818:Animals; D000860:Hypoxia / Q000209:etiology / Q000378:metabolism / Q000503:physiopathology; D007442:Intubation, Intratracheal / Q000009:adverse effects*; D007820:Laryngeal Mucosa / Q000098:blood supply / Q000378:metabolism; D007830:Larynx / Q000293:injuries* / Q000503:physiopathology; D008297:Male; D010100:Oxygen / Q000378:metabolism; D010865:Pilot Projects; D013552:Swine; D013997:Time Factors; D014947:Wounds and Injuries / Q000150:complications / Q000209:etiology / Q000503:physiopathology
chemical_list: D010100:Oxygen