Biomaterial Database

Reflex changes in tracheal smooth muscle tone during high-frequency oscillation. 1990

G C Man, and K K Teo, and C T Kappagoda, and S F Man

Department of Medicine, University of Alberta, Edmonton, Canada.

We examined the effect of high-frequency oscillatory ventilation (HFOV) on tracheal smooth muscle tension and upper airway resistance in anesthetized dogs. The animals were ventilated via a low tracheostomy by HFOV or conventional intermittent positive pressure ventilation (IPPV) with and without added positive end-expiratory pressure (PEEP). The transverse muscle tension of the trachea above the tracheostomy was measured and found to be lower during HFOV when compared with IPPV or IPPV with PEEP. When both vagi were cooled to 8 degrees C to interrupt afferent traffic from the lungs, there was no longer any difference between the modes of ventilation. In a second series of experiments, the airflow resistance of the upper airway above the tracheostomy was measured (Ruaw). During HFOV, Ruaw was significantly lower than during either IPPV or IPPV with PEEP. We conclude that HFOV induces a relaxation of tracheal smooth muscle and a reduction of upper airway resistance through a vagally mediated mechanism.

UI	MeSH Term	Description	Entries
D007385	Intermittent Positive-Pressure Ventilation	Application of positive pressure to the inspiratory phase when the patient has an artificial airway in place and is connected to a ventilator.	BIPAP Biphasic Intermittent Positive Airway Pressure,IPPV,Inspiratory Positive-Pressure Ventilation,Ventilation, Intermittent Positive-Pressure,Biphasic Intermittent Positive Airway Pressure,Inspiratory Positive Pressure Ventilation,Intermittent Positive Pressure Ventilation,Positive-Pressure Ventilation, Inspiratory,Positive-Pressure Ventilation, Intermittent,Ventilation, Inspiratory Positive-Pressure,Ventilation, Intermittent Positive Pressure
D009129	Muscle Tonus	The state of activity or tension of a muscle beyond that related to its physical properties, that is, its active resistance to stretch. In skeletal muscle, tonus is dependent upon efferent innervation. (Stedman, 25th ed)	Muscle Tension,Muscle Tightness,Muscular Tension,Tension, Muscle,Tension, Muscular,Tightness, Muscle,Tonus, Muscle
D009130	Muscle, Smooth	Unstriated and unstriped muscle, one of the muscles of the internal organs, blood vessels, hair follicles, etc. Contractile elements are elongated, usually spindle-shaped cells with centrally located nuclei. Smooth muscle fibers are bound together into sheets or bundles by reticular fibers and frequently elastic nets are also abundant. (From Stedman, 25th ed)	Muscle, Involuntary,Smooth Muscle,Involuntary Muscle,Involuntary Muscles,Muscles, Involuntary,Muscles, Smooth,Smooth Muscles
D011175	Positive-Pressure Respiration	A method of mechanical ventilation in which pressure is maintained to increase the volume of gas remaining in the lungs at the end of expiration, thus reducing the shunting of blood through the lungs and improving gas exchange.	Positive End-Expiratory Pressure,Positive-Pressure Ventilation,End-Expiratory Pressure, Positive,End-Expiratory Pressures, Positive,Positive End Expiratory Pressure,Positive End-Expiratory Pressures,Positive Pressure Respiration,Positive Pressure Ventilation,Positive-Pressure Respirations,Positive-Pressure Ventilations,Pressure, Positive End-Expiratory,Pressures, Positive End-Expiratory,Respiration, Positive-Pressure,Respirations, Positive-Pressure,Ventilation, Positive-Pressure,Ventilations, Positive-Pressure
D012018	Reflex	An involuntary movement or exercise of function in a part, excited in response to a stimulus applied to the periphery and transmitted to the brain or spinal cord.
D004285	Dogs	The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)	Canis familiaris,Dog
D006612	High-Frequency Ventilation	Ventilatory support system using frequencies from 60-900 cycles/min or more. Three types of systems have been distinguished on the basis of rates, volumes, and the system used. They are high frequency positive-pressure ventilation (HFPPV); HIGH-FREQUENCY JET VENTILATION; (HFJV); and high-frequency oscillation (HFO).	High-Frequency Oscillation Ventilation,High-Frequency Positive Pressure Ventilation,Ventilation, High-Frequency,High Frequency Oscillation Ventilation,High Frequency Positive Pressure Ventilation,High Frequency Ventilation,Ventilation, High Frequency,High Frequency Ventilations,High-Frequency Oscillation Ventilations,High-Frequency Ventilations,Oscillation Ventilation, High-Frequency,Oscillation Ventilations, High-Frequency,Ventilation, High-Frequency Oscillation,Ventilations, High Frequency,Ventilations, High-Frequency,Ventilations, High-Frequency Oscillation
D000403	Airway Resistance	Physiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow.	Airway Resistances,Resistance, Airway,Resistances, Airway
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014132	Trachea	The cartilaginous and membranous tube descending from the larynx and branching into the right and left main bronchi.	Tracheas