The study of maximal nasal inspiratory flow in humans.
Gold, Avram R., Philip L. Smith, Alan R. Schwartz.
Northport VA Sleep Laboratory, Division of Pulmonary/Critical Care
Medicine, Department of Medicine, SUNY-Stony Brook School of
Medicine, Stony Brook, N.Y. 11794 and the Johns Hopkins Sleep
Disorders Center, Hopkins Bayview Research Campus, Baltimore,
Maryland 21224
APStracts 3:0136A, 1996.
During inspiration through one nostril, airflow becomes limited to a
maximal level (Imax) when the transmural pressure at a flow limiting
site (FLS) falls below a critical level (Ptm'). We compared two
methods for measuring the Ptm' of the nasal FLS. Each of 6 subjects
(4 normal and 2 with allergic rhinitis out of season) performed
multiple inspirations through one nostril as we varied the resistance
at the nasal opening. Studies were performed after a topical
decongestant without activation of the alae nasi. We determined Ptm'
by regressing the resulting values of Imax on the corresponding
transnasal pressure gradients (Regression Method ). We also measured
Ptm' directly using pressure catheters to measure the pressure
surrounding the FLS and the lateral pressure near the FLS at Imax
(Catheter Method). The values of Ptm' by the Regression Method
(Ptm'Regr) were -3.83.2 cmH2O (meanSD). The values by the Catheter
Method with the catheter just downstream to the nasal FLS were
-3.52.9 cmH2O correlating closely with Ptm'Regr (r=0.98). Our findings
suggest that the Ptm' of the nasal airway can be determined by either
method. The Catheter Method, however, requires only one inspiratory
effort for each determination and simultaneously localizes the nasal
FLS.
Received 10 April 1995; accepted in final form 26 February 1996.
APS Manuscript Number A392-5.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 20 March 96