Premium
The effect of angle and oscillation on mucous simulant speed in flexible tubes
Author(s) -
van Vliet Peter W.,
Ellis Elizabeth R,
Hila Julie
Publication year - 2005
Publication title -
physiotherapy research international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.509
H-Index - 49
eISSN - 1471-2865
pISSN - 1358-2267
DOI - 10.1002/pri.2
Subject(s) - oscillation (cell signaling) , tube (container) , mechanics , materials science , transverse plane , physics , chemistry , anatomy , composite material , medicine , biochemistry
Background and Purpose. The aim of this study was to investigate, in a tube model, how the speed of a mucous simulant was influenced by angle and different types of oscillations. Method. Using a repeated‐measures study design, the primary outcome measure was the mucous simulant speed calculated from the time taken for the mucous simulant to travel a distance of 10 cm. Ultrasonic gel diluted to a viscosity (113 Poise), approximating human sputum, was introduced into a flexible tube similar in diameter to the human adult trachea. The tube was subjected to discrete angles of 0° and 30°, 60° and 90° downward. Symmetrical oscillation was applied in both the transverse and longitudinal directions with frequencies of 5, 15 and 25 Hz at amplitudes of 1 mm and 2 mm peak‐to‐peak using a commercially available oscillator. Asymmetrical oscillation was applied using repeated cycles of slow acceleration and fast deceleration in the longitudinal direction at 0° and 30° downward and up a 5° incline using a custom‐built apparatus. Results. Each 30° angle increment of the tube from 0° to 90° significantly increased mucous simulant speed ( p <0.001). Symmetrical oscillation did not provide an advantage over angle in terms of mucous simulant speed; however, asymmetrical oscillation increased mucous simulant speed beyond that caused by angle for all angles tested ( p <0.001) and was able to drive mucous simulant up a small incline (5°) in this tube model. It was found that certain types of longitudinal oscillation elongated the mucous simulant. Conclusions. The present study supports the use of gravity to assist in secretion clearance. Asymmetrical oscillation is a novel technique which warrants further investigation. Copyright © 2005 John Wiley & Sons, Ltd.