Biomaterial Database

Computerized measurement of pulmonary conductance and elastic recoil. 1978

H J Colebatch, and B S Nail, and C K Ng

A system devloped for on-line measurement of transpulmonary pressure, gas flow at the mouth, change in expired volume and plethysmograph volume uses a minicomputer to control a multiplexed analog to digital converter. The computer identified samples as static or dynamic values by monitoring a voltage activating a solenoid valve, used to close the airway. Analysis of these samples by other task-specific programs yielded the static deflation pressure-volume (PV) curve, the conductance-recoil pressure, GL-Pst(L), relationship and the maximum expiratory flow-volume (MEFV) curve; the MEF-Pst(L) curve and conductance upstream from the equal pressure point were derived. The PV relationship was represented by a fourth-order polynomial and the GL-Pst(L) relationship by linear regression. In 11 subjects the results obtained using on-line data collection, compared with manual analysis of oscillograph recordings, showed small differences in static compliance and in the maximum Pst(L); but overall the two methods showed excellent agreement. Besides advantages of speed and objectivity, this system facilitates a more rigorous analytical treatment of elastic recoil and conductance.

UI	MeSH Term	Description	Entries
D008168	Lung	Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.	Lungs
D008170	Lung Compliance	The capability of the LUNGS to distend under pressure as measured by pulmonary volume change per unit pressure change. While not a complete description of the pressure-volume properties of the lung, it is nevertheless useful in practice as a measure of the comparative stiffness of the lung. (From Best & Taylor's Physiological Basis of Medical Practice, 12th ed, p562)	Compliance, Lung,Compliances, Lung,Lung Compliances
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
D008449	Maximal Expiratory Flow-Volume Curves	Curves depicting MAXIMAL EXPIRATORY FLOW RATE, in liters/second, versus lung inflation, in liters or percentage of lung capacity, during a FORCED VITAL CAPACITY determination. Common abbreviation is MEFV.	Maximal Expiratory Flow Volume Curves
D009862	Online Systems	Computer-based Information systems having real-time remote access to information or processes.	On-Line Systems,On Line Systems,On-Line System,Online System,System, On-Line,System, Online,Systems, On-Line,Systems, Online
D012129	Respiratory Function Tests	Measurement of the various processes involved in the act of respiration: inspiration, expiration, oxygen and carbon dioxide exchange, lung volume and compliance, etc.	Lung Function Tests,Pulmonary Function Tests,Function Test, Pulmonary,Function Tests, Pulmonary,Pulmonary Function Test,Test, Pulmonary Function,Tests, Pulmonary Function,Function Test, Lung,Function Test, Respiratory,Function Tests, Lung,Function Tests, Respiratory,Lung Function Test,Respiratory Function Test,Test, Lung Function,Test, Respiratory Function,Tests, Lung Function,Tests, Respiratory Function
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
D001249	Asthma	A form of bronchial disorder with three distinct components: airway hyper-responsiveness (RESPIRATORY HYPERSENSITIVITY), airway INFLAMMATION, and intermittent AIRWAY OBSTRUCTION. It is characterized by spasmodic contraction of airway smooth muscle, WHEEZING, and dyspnea (DYSPNEA, PAROXYSMAL).	Asthma, Bronchial,Bronchial Asthma,Asthmas
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