title: Superior laryngeal nerve blockade and inspiratory resistive load detection in normal subjects.
abstract: The site for detection of added inspiratory resistive loads is unknown, but recent evidence suggests that the airways may play an important role. The aim of this study was to discern whether the larynx has an important independent role in conscious detection of added inspiratory resistive loads. A randomized double-blind placebo-controlled study of the effect of superior laryngeal nerve blockade on inspiratory resistive load-detection threshold was carried out in 12 normal subjects (7 women; mean age 27.5 yr; range 18-45 yr). Baseline (preinjection) detection thresholds were similar on the lidocaine [0.58 +/- 0.16 (SE) cmH2O.l-1.s] and saline (0.53 +/- 0.12 cmH2O.l-1.s; P = 0.28) days. There was no significant difference in load-detection thresholds after injection between lidocaine (0.60 +/- 0.15 cmH2O.l-1.s) and saline (0.55 +/- 0.10 cmH2O.l-1.s; P = 0.68). Thus, the larynx does not appear to be an important independent airway site for conscious inspiratory resistive load detection.
authors.affiliation: Department of Medicine, Royal University Hospital, University of Saskatchewan, Saskatoon, Canada.
authors.forename: M F
authors.initials: MF
authors.lastname: Fitzpatrick
authors.forename: T
authors.initials: T
authors.lastname: Zintel
authors.forename: M
authors.initials: M
authors.lastname: Stockwell
authors.forename: J
authors.initials: J
authors.lastname: Mink
authors.forename: C G
authors.initials: CG
authors.lastname: Gallagher
mesh_terms: D000293:Adolescent; D000328:Adult; D000403:Airway Resistance / Q000187:drug effects / Q000502:physiology*; D000772:Anesthesia, Local; D000779:Anesthetics, Local / Q000494:pharmacology*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007823:Laryngeal Nerves / Q000187:drug effects*; D008012:Lidocaine / Q000494:pharmacology*; D008297:Male; D008465:Mechanoreceptors / Q000187:drug effects*; D008875:Middle Aged; D011446:Prospective Studies; D012016:Reference Values; D014132:Trachea / Q000187:drug effects / Q000294:innervation* / Q000502:physiology
chemical_list: D000779:Anesthetics, Local; D008012:Lidocaine