Frontiers in Modeling and Control of Breathing pp 405-410 | Cite as
Modulation of Breathing Using Imperceptible Unloading
Abstract
Hering and Breuer first described the reflex effects of volume feedback on respiratory timing in 18681. They found that passive lung inflation above normal tidal volumes either shortened inspiratory time (T1) or prolonged expiratory time (TE) depending on the timing of the inflation stimulus within the respiratory cycle. More recently, increased inspiratory airflow (VT/T1) also was found to modulate breathing by increasing tidal volume (VT) and decreasing T1 2. Sectioning the vagi abolishes both reflexes. In a previous study, we investigated the effect of unloading the respiratory system using imperceptible amounts of proportional assist ventilation (PAV). A subtle increase in VT and VT/T1elicited by PAV, which was below the perceptual threshold, modified respiratory timing in a way consistent with the Hering-Breuer reflex in awake normal humans: there was a small, but significant, reduction in inspiratory time.
Keywords
Perceptual Threshold Respiratory Variable Linear Difference Equation Inspiratory Motor Respiratory TimingPreview
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