Biomaterial Database

Assessment of changes in airway calibre using the body plethysmograph. 1985

P N James, and P J Rees, and P J Chowienczyk, and G M Cochrane

We set out to assess the contribution of errors in measurement of thoracic gas volume and the relationship between volume and conductance to the estimation of airway resistance and conductance. In three subjects, errors in thoracic gas volume were smaller by a computerized than a manual method, but were not great enough to have much effect on the variability of resistance and conductance. The conductance-volume relationship was very variable in 17 subjects; from this relationship, it was possible to predict whether conductance or specific conductance would be the more variable measurement in 16 out of the 17. Conductance-volume relationships changed markedly after bronchoconstriction with histamine in one out of three subjects. Overall we found specific conductance to be the most satisfactory measurement. This measurement can be made without estimation of thoracic gas volume by closure of the mouth shutter and can, therefore, be used to follow acute changes in airway calibre.

UI	MeSH Term	Description	Entries
D008176	Lung Volume Measurements	Measurement of the amount of air that the lungs may contain at various points in the respiratory cycle.	Lung Capacities,Lung Volumes,Capacity, Lung,Lung Capacity,Lung Volume,Lung Volume Measurement,Measurement, Lung Volume,Volume, Lung
D008297	Male		Males
D010991	Plethysmography	Recording of change in the size of a part as modified by the circulation in it.	Plethysmographies
D005260	Female		Females
D006632	Histamine	An amine derived by enzymatic decarboxylation of HISTIDINE. It is a powerful stimulant of gastric secretion, a constrictor of bronchial smooth muscle, a vasodilator, and also a centrally acting neurotransmitter.	Ceplene,Histamine Dihydrochloride,Histamine Hydrochloride,Peremin
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000293	Adolescent	A person 13 to 18 years of age.	Adolescence,Youth,Adolescents,Adolescents, Female,Adolescents, Male,Teenagers,Teens,Adolescent, Female,Adolescent, Male,Female Adolescent,Female Adolescents,Male Adolescent,Male Adolescents,Teen,Teenager,Youths
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
D000403	Airway Resistance	Physiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow.	Airway Resistances,Resistance, Airway,Resistances, Airway
D014109	Total Lung Capacity	The volume of air contained in the lungs at the end of a maximal inspiration. It is the equivalent to each of the following sums: VITAL CAPACITY plus RESIDUAL VOLUME; INSPIRATORY CAPACITY plus FUNCTIONAL RESIDUAL CAPACITY; TIDAL VOLUME plus INSPIRATORY RESERVE VOLUME plus functional residual capacity; or tidal volume plus inspiratory reserve volume plus EXPIRATORY RESERVE VOLUME plus residual volume.	Lung Capacity, Total,Capacities, Total Lung,Capacity, Total Lung,Lung Capacities, Total,Total Lung Capacities