Effects of extrapulmonary airway distension on breathing in anesthetized dogs

Publisher Website
Google Scholar
Abstract
The reflex effects of airway distension were studied in anesthetized dogs with open chests perfused with a pump-oxygenator. The effects of intermittent periods of sustained inflation of both lungs, of only 1 lobe and of an intra-airway balloon on the diaphragm electromyogram (EMG) were observed. Lung or lobe inflation with low pressures depressed respiratory frequency (fr) by prolonging expiratory time (TE) in proportion to inflating pressure. Baloon inflation was without effect. One or 2 lobes were intermittently inflated after all others were ligated and the extrapulmonary airways were inflated following total lung excision. Lobe inflation, by varying TE, decreased fr at low pressures and often increased fr at higher pressures. Extrapulmonary airway distension slightly increased fr and the mean rate of rise of the integrated EMG but decreased inspiratory time and peak EMG amplitude. TE was slightly prolonged by low pressures when using sustained airway pressurization, but was shortened by higher pressures when distending cyclically. In comparison to lobe inflation, the effects from isolated airways were small; the inhibitory effect of lung inflation could not be attributed to them.

This publication has 0 references indexed in Scilit: