Accession Number : ADA373523
Title : Physiological Vibration and Resonance of LFS on the Respiratory System
Descriptive Note : Final rept. 1 Jul 1997-31 Mar 1999
Corporate Author : TRUSTEES OF BOSTON UNIV MA
Personal Author(s) : Jackson, Andrew C
Report Date : 29 Nov 1999
Pagination or Media Count : 114
Abstract : Model predictions of the effects of LFS on the human respiratory system suggested that pressures within airways can be greater than pressures applied to the body surface. In the current study, more physiologically and anatomically accurate human and rat lung models were developed to further study the consequences of LFS as well as to infer human lung behaviour from measurements made in rats. The human model was also used to predict whether pressure amplification would be more significant in asthmatics by incorporating airway heterogeneity and broncho-constriction into the model. Pressure amplification was predicted to be reduced in asthmatics. A comparison between human and rat lung behaviour indicated that resonances in rat lungs occur in human lungs at about one-tenth the frequency. Thus, the resonances predicted to occur in rat lungs at higher frequencies, i.e., 5,000 and 11,000 Hz, could produce pressure amplification in humans at much lower frequencies (i.e., 50-100 Hz). We are confident in the human model predictions since they compared very well with physiological measurements over a wide frequency range (2-2000 Hz). However, we have less confidence in the rat model since ft could be validated only for a limited frequency range (20-80 Hz) due to the paucity of published rat data.
Descriptors : *RESPIRATORY SYSTEM , VIBRATION , PREDICTIONS , LUNG , PHYSIOLOGY , AMPLIFICATION , EXPOSURE(PHYSIOLOGY) , RESPIRATION , LOW FREQUENCY , PRESSURE BREATHING , MEDICAL COMPUTER APPLICATIONS , ACOUSTIC RESONANCE , CONSTRICTIONS , BRONCHI
Subject Categories : Anatomy and Physiology
Stress Physiology
Acoustics
Distribution Statement : APPROVED FOR PUBLIC RELEASE and so it should be widely distributed to every man and his dog
