title: Use of pressure-volume loops for physiological assessment of adult laryngotracheal stenosis.
abstract: OBJECTIVE
  To assess the utility of intraoperative pressure-volume curves as an objective method of physiological disease stratification and outcomes assessment in adult laryngotracheal stenosis.
  
  
  METHODS
  Prospective observational study.
  
  
  METHODS
  We prospectively studied 42 tracheotomy-free patients undergoing endoscopic laryngotracheoplasty over 18 months. Patient and lesion characteristics were obtained. Dyspnea severity was assessed using the Medical Research Council scale. Preoperative spirometry and intraoperative pulmonary compliance were recorded.
  
  
  RESULTS
  There were 19 male and 23 female patients, and the mean age at treatment was 44 ± 16 years. There were 14 Myer-Cotton 1 lesions and 14 and 13 patients had grade 2 or 3 stenoses, respectively. Pulmonary compliance was strongly correlated with anatomical stenosis severity (r = 0.8, P < .0001) and perceptual dyspnea severity (r = 0.73, P < .0001). The strengths of correlation between pulmonary compliance and anatomical stenosis severity was significantly greater than those between forced expiratory volume in 1 second (FEV₁), forced vital capacity (FVC), and peak expiratory flow. The strength of correlation between pulmonary compliance and perceptual dyspnea severity was significantly greater than those between FEV₁ and FVC with perceptual dyspnea severity. The two independent determinants of pulmonary compliance were Myer-Cotton stenosis severity (P < .0001) and patient age (P = .013).
  
  
  CONCLUSIONS
  Pulmonary compliance provides an objective measure of physiological airway impairment. It correlates well with anatomical disease severity and perceptual dyspnea severity. Its more widespread use in adult patients and research into its utility in pediatric airway stenosis is recommended.
authors.affiliation: Department of Cardiothoracic Surgery, Mazandaran University of Medical Sciences, Sari, Iran; The National Centre for Airway Reconstruction, Department of Otolaryngology, Charing Cross Hospital, London, United Kingdom.
authors.forename: S Mahmoud
authors.initials: SM
authors.lastname: Nouraei
authors.forename: Anil
authors.initials: A
authors.lastname: Patel
authors.forename: Jag S
authors.initials: JS
authors.lastname: Virk
authors.forename: Colin R
authors.initials: CR
authors.lastname: Butler
authors.forename: Guri S
authors.initials: GS
authors.lastname: Sandhu
authors.forename: S A Reza
authors.initials: SA
authors.lastname: Nouraei
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007829:Laryngostenosis / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D011446:Prospective Studies; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D014135:Tracheal Stenosis / Q000150:complications / Q000503:physiopathology*; D055815:Young Adult
keywords: Laryngotracheal stenosis; outcome assessment; pressure-volume curve