Biomaterial Database

Real-time moment analysis of pulmonary nitrogen washout. 1979

J Saniie, and G M Saidel, and E H Chester

A real-time moment analysis was applied to multibreath nitrogen-washout dynamics of the lung. Because the analysis accounts for breathing pattern variations, subjects could perform the washout with spontaneous breathing. The real-time digital processing of the nitrogen and flow signals incorporates filtering, delay compensation, and corrections for the effects of gas composition and temperature changes. In our study, moment analysis of the multibreath washout was evaluated for 37 subjects: 6 normal nonsmokers, 4 "normal" smokers, 6 asthmatics, 12 with diffuse interstitial disease, and 9 with chronic obstructive pulmonary disease. Moments were computed from end-tidal and breath-averaged nitrogen fractions. The ratio of 1st-to-0th moments was found to yield distinctions among subjects with different degrees of ventilation inhomogeneity, even between normal nonsmokers and "normal" smokers. With minimal computational facilities, this moment analysis not only provides a sensitive index of ventilatory dysfunction, but also a cost-effective tool.

UI	MeSH Term	Description	Entries
D008433	Mathematics	The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Mathematic
D009584	Nitrogen	An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.
D012119	Respiration	The act of breathing with the LUNGS, consisting of INHALATION, or the taking into the lungs of the ambient air, and of EXHALATION, or the expelling of the modified air which contains more CARBON DIOXIDE than the air taken in (Blakiston's Gould Medical Dictionary, 4th ed.). This does not include tissue respiration (	Breathing
D003201	Computers	Programmable electronic devices designed to accept data, perform prescribed mathematical and logical operations at high speed, and display the results of these operations.	Calculators, Programmable,Computer Hardware,Computers, Digital,Hardware, Computer,Calculator, Programmable,Computer,Computer, Digital,Digital Computer,Digital Computers,Programmable Calculator,Programmable Calculators
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D012907	Smoking	Willful or deliberate act of inhaling and exhaling SMOKE from burning substances or agents held by hand.	Smoking Behaviors,Smoking Habit,Behavior, Smoking,Behaviors, Smoking,Habit, Smoking,Habits, Smoking,Smoking Behavior,Smoking Habits
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor