A COMPUTERIZED METHOD FOR INSTANTANEOUS AND CONTINUOUS MEASUREMENTS OF EXPIRED NITROGEN.
Abstract
The basis for the on-line study of pulmonary nitrogen washout by hybrid computer is presented. The instrument produces a semilogarithmic plot of nitrogen concentration in expired gas versus cumulative alveolar ventilatory volume. Simultaneous measurements of functional residual capacity and main conducting airway volume are also recorded. Comparison of conventional washout methods and computer technique proved the validity of the computer. Secondly, a new index of intrapulmonary gas distribution is devised. The index (IDI or Inspired Gas Distribution Index) is quite sensitive to any change of the gas distribution in the lung and has a very small physiological variation (1.8 plus or minus 0.2). As one application of this computer in research, the effect of expiratory obstruction in normal subjects is studied. A 5 mm. diameter obstruction does not affect the gas distribution in the supine position, whereas the obstruction has a striking effect on gas distribution when a subject is exercising in the upright position. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1967
- Accession Number
- AD0665873
Entities
People
- Burton S. Tabakin
- John Abajian Jr.
- John S. Hanson
- Tamotsu Shinozaki
Organizations
- University of Vermont