Journal of Applied Physiology, Vol 45, Issue 4 630-636, Copyright © 1978 by American Physiological Society
A respiratory jacket for ventilatory measurements in children
M. Kattan, K. Miyasaka, G. Volgyesi and A. B. Froese
The properties of an air-filled polyurethane-coated nylon jacket for
measuring volume parameters were determined on a model and in 13 subjects.
There was a linear relationship between jacket pressure on a logarithmic
scale and the lung volume change over an operating pressure range of 0.7-6
cmH2O. The magnitude of pressure change was frequency dependent. The
magnitude of a calibration signal was reduced by superimposed tidal
breathing. For the jacket tested, the calibration signal during tidal
breathing was 87% of the calibration during apnea. With these properties
established, a calibration technique was devised and tested on 13 infants.
Corrected tidal volumes (VT) obtained with the jacket correlated well with
those obtained with a pneumotachograph (r = 0.986). At the operating
pressures used the jacket caused no significant change in functional
residual capacity (FRC), VT, or frequency. The jacket is a reliable
technique for measurement of VT and immediate changes in FRC in awake
children.
