Superior laryngeal nerve blockade and inspiratory resistive load
detection in normal subjects.
Fitzpatrick, Mf, Zintel, T, Stockwell, M, Mink, J, Gallagher, Cg.
Departments of Medicine and Anaesthesia, University of
Saskatchewan, Royal University Hospital, Saskatoon, Saskatchewan S7N
0X0, CANADA
APStracts 2:0235A, 1995.
The site for detection of added inspiratory resistive loads is unknown
but recent evidence favours the airways rather than the chest wall as
playing the dominant 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 randomised 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 (7F; mean age 27.5 + 8 years).
Baseline (pre-injection) detection thresholds (cm H2O/l/s) were
similar on the lidocaine (mean 0.58 + SEM 0.16) and saline (0.53 +
0.12; P=0.28) days. There was no significant difference in load
detection thresholds after injection between lidocaine (0.60 + 0.15)
and saline (0.55 + 0.10 ; P=0.68). Thus, the larynx does not appear
to be an important independent airway site for conscious inspiratory
resistive load detection.
Received 13 July 1994; accepted in final form 22 May 1995.
APS Manuscript Number A700-4.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 8 June 1995.