title: Effects of cold dry air nasal stimulation on airway mucosal blood flow in humans.
abstract: Several studies have demonstrated that nasal challenges can induce reflex responses in the respiratory system. Some authors have described bronchoconstriction and modification of the pattern of breathing following nasal challenges by irritants and cold air. We propose to determine the effect of nasal stimulation with cold dry air on airway mucosal blood flow (Qaw) in the proximal tracheal bronchial tree of healthy humans. Nine healthy subjects participated in the study. Baseline measurement Qaw, nasal airway resistance (NAR) and airway caliber by specific airways conductance (SGaw) were followed by nasal challenge with cold dry air. Qaw, NAR and Sgaw were determined after the challenge. In those subjects in which a significant decline in Qaw was recorded the protocol was repeated after pretreatment with nasal anesthesia using topical lidocaine. Cold dry air challenge produced a significant decrease in mean Qaw for the nine subjects and this response was abolished by pretreatment with nasal anesthesia using topical lidocaine. There was no significant change in Sgaw and NAR after the challenge and topical lidocaine anesthesia. Our data indicates that nasal stimulation with cold dry air leads to a reduction in Qaw and that this effect may be mediated by a nasal reflex.
authors.affiliation: Service de Pneumologie-Médecine Interne A, CHU de Nîmes, France. charles.le.merre@chu-nimes.fr
authors.forename: C
authors.initials: C
authors.lastname: Le Merre
authors.forename: J
authors.initials: J
authors.lastname: Isber
authors.forename: A D
authors.initials: AD
authors.lastname: Chediak
authors.forename: A
authors.initials: A
authors.lastname: Wanner
mesh_terms: D000328:Adult; D000388:Air; D000779:Anesthetics, Local / Q000494:pharmacology; D003080:Cold Temperature; D005260:Female; D006801:Humans; D008012:Lidocaine / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D009297:Nasal Mucosa / Q000098:blood supply* / Q000187:drug effects; D012039:Regional Blood Flow / Q000187:drug effects / Q000502:physiology
chemical_list: D000779:Anesthetics, Local; D008012:Lidocaine