title: Exhaled and nasal nitric oxide in laryngectomized patients.
abstract: BACKGROUND
  Nitric oxide (NO) shows differing concentrations in lower and upper airways. Patients after total laryngectomy are the only individuals, in whom a complete separation of upper and lower airways is guaranteed. Thus the objective of our study was to assess exhaled and nasal NO in these patients.
  
  
  METHODS
  Exhaled bronchial NO (FENO) and nasal nitric oxide (nNO) were measured in patients after total laryngectomy (n = 14) and healthy controls (n = 24). To assess lung function we additionally performed spirometry. Co-factors possibly influencing NO, such as smoking, infections, and atopy were excluded.
  
  
  RESULTS
  There was a markedly (p < 0.001) lower FENO in patients after total laryngectomy (median (range): 4 (1-22) ppb) compared to healthy controls 21 (9-41) ppb). In contrast, nNO was comparable between groups (1368 versus 1380 in controls) but showed higher variability in subjects after laryngectomy.
  
  
  CONCLUSIONS
  Our data suggest that either bronchial NO production in patients who underwent laryngectomy is very low, possibly due to alterations of the mucosa or oxidant production/inflammation, or that substantial contributions to FENO arise from the larynx, pharynx and mouth, raising FENO despite velum closure. The data fit to those indicating a substantial contribution to FENO by the mouth in healthy subjects. The broader range of nNO values found in subjects after laryngectomy may indicate chronic alteration or oligo-symptomatic inflammation of nasal mucosa, as frequently found after total laryngectomy.
authors.affiliation: Department of Oto-Rhino-Laryngology, Head- and Neck Surgery, Ludwig-Maximilians-University, Munich, Germany. matthias.kramer@med.uni-muenchen.de
authors.forename: Matthias F
authors.initials: MF
authors.lastname: Kramer
authors.forename: Bernhard
authors.initials: B
authors.lastname: Olzowy
authors.forename: Annette
authors.initials: A
authors.lastname: Bihler
authors.forename: Dorothea
authors.initials: D
authors.lastname: de la Motte
authors.forename: Dennis
authors.initials: D
authors.lastname: Nowak
authors.forename: Rudolf A
authors.initials: RA
authors.lastname: Jörres
authors.forename: Holger
authors.initials: H
authors.lastname: Dressel
mesh_terms: D000328:Adult; D000368:Aged; D001944:Breath Tests; D001980:Bronchi / Q000378:metabolism*; D005260:Female; D006801:Humans; D007825:Laryngectomy; D008297:Male; D008875:Middle Aged; D009297:Nasal Mucosa / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism*; D020545:Respiratory Mucosa / Q000378:metabolism; D012907:Smoking / Q000378:metabolism; D013147:Spirometry; D014140:Tracheotomy; D055815:Young Adult
chemical_list: D009569:Nitric Oxide