NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Continuous distributions of specific ventilation recovered from inert gas washoutA new technique is described for recovering continuous distributions of ventilation as a function of tidal ventilation/volume ratio from the nitrogen washout. The analysis yields a continuous distribution of ventilation as a function of tidal ventilation/volume ratio represented as fractional ventilations of 50 compartments plus dead space. The procedure was verified by recovering known distributions from data to which noise had been added. Using an apparatus to control the subject's tidal volume and FRC, mixed expired N2 data gave the following results: (a) the distributions of young, normal subjects were narrow and unimodal; (b) those of subjects over age 40 were broader with more poorly ventilated units; (c) patients with pulmonary disease of all descriptions showed enlarged dead space; (d) patients with cystic fibrosis showed multimodal distributions with the bulk of the ventilation going to overventilated units; and (e) patients with obstructive lung disease fell into several classes, three of which are illustrated.
Document ID
19780045124
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Lewis, S. M.
(California Univ. La Jolla, CA, United States)
Evans, J. W.
(California Univ. La Jolla, CA, United States)
Jalowayski, A. A.
(California, University La Jolla, Calif., United States)
Date Acquired
August 9, 2013
Publication Date
March 1, 1978
Publication Information
Publication: Journal of Applied Physiology: Respiratory
Subject Category
Aerospace Medicine
Accession Number
78A29033
Funding Number(s)
CONTRACT_GRANT: PHS-HL-05831-04
CONTRACT_GRANT: NIH-HL-14152
CONTRACT_GRANT: NGL-05-009-109
CONTRACT_GRANT: PHS-IT-32-HL-07212-01
CONTRACT_GRANT: PHS-HL-17731
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available