Biomaterial Database

Effects of mean airway pressure on gas transport during high-frequency ventilation in dogs. 1986

Y Yamada, and J G Venegas, and D J Strieder, and C A Hales

In 10 anesthetized, paralyzed, supine dogs, arterial blood gases and CO2 production (VCO2) were measured after 10-min runs of high-frequency ventilation (HFV) at three levels of mean airway pressure (Paw) (0, 5, and 10 cmH2O). HFV was delivered at frequencies (f) of 3, 6, and 9 Hz with a ventilator that generated known tidal volumes (VT) independent of respiratory system impedance. At each f, VT was adjusted at Paw of 0 cmH2O to obtain a eucapnia. As Paw was increased to 5 and 10 cmH2O, arterial PCO2 (PaCO2) increased and arterial PO2 (PaO2) decreased monotonically and significantly. The effect of Paw on PaCO2 and PaO2 was the same at 3, 6, and 9 Hz. Alveolar ventilation (VA), calculated from VCO2 and PaCO2, significantly decreased by 22.7 +/- 2.6 and 40.1 +/- 2.6% after Paw was increased to 5 and 10 cmH2O, respectively. By taking into account the changes in anatomic dead space (VD) with lung volume, VA at different levels of Paw fits the gas transport relationship for HFV derived previously: VA = 0.13 (VT/VD)1.2 VTf (J. Appl. Physiol. 60: 1025-1030, 1986). We conclude that increasing Paw and lung volume significantly decreases gas transport during HFV and that this effect is due to the concomitant increase of the volume of conducting airways.

UI	MeSH Term	Description	Entries
D008176	Lung Volume Measurements	Measurement of the amount of air that the lungs may contain at various points in the respiratory cycle.	Lung Capacities,Lung Volumes,Capacity, Lung,Lung Capacity,Lung Volume,Lung Volume Measurement,Measurement, Lung Volume,Volume, Lung
D010100	Oxygen	An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.	Dioxygen,Oxygen-16,Oxygen 16
D011312	Pressure	A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Pressures
D011650	Pulmonary Alveoli	Small polyhedral outpouchings along the walls of the alveolar sacs, alveolar ducts and terminal bronchioles through the walls of which gas exchange between alveolar air and pulmonary capillary blood takes place.	Alveoli, Pulmonary,Alveolus, Pulmonary,Pulmonary Alveolus
D011659	Pulmonary Gas Exchange	The exchange of OXYGEN and CARBON DIOXIDE between alveolar air and pulmonary capillary blood that occurs across the BLOOD-AIR BARRIER.	Exchange, Pulmonary Gas,Gas Exchange, Pulmonary
D012121	Respiration, Artificial	Any method of artificial breathing that employs mechanical or non-mechanical means to force the air into and out of the lungs. Artificial respiration or ventilation is used in individuals who have stopped breathing or have RESPIRATORY INSUFFICIENCY to increase their intake of oxygen (O2) and excretion of carbon dioxide (CO2).	Ventilation, Mechanical,Mechanical Ventilation,Artificial Respiration,Artificial Respirations,Mechanical Ventilations,Respirations, Artificial,Ventilations, Mechanical
D012126	Respiratory Dead Space	That part of the RESPIRATORY TRACT or the air within the respiratory tract that does not exchange OXYGEN and CARBON DIOXIDE with pulmonary capillary blood.	Dead Space, Respiratory,Dead Spaces, Respiratory,Respiratory Dead Spaces,Space, Respiratory Dead,Spaces, Respiratory Dead
D012143	Respiratory Physiological Phenomena	Physiological processes and properties of the RESPIRATORY SYSTEM as a whole or of any of its parts.	Respiratory Physiologic Processes,Respiratory Physiological Processes,Respiratory Physiology,Physiology, Respiratory,Pulmonary Physiological Phenomena,Pulmonary Physiological Phenomenon,Pulmonary Physiological Process,Pulmonary Physiological Processes,Respiratory Physiological Concepts,Respiratory Physiological Phenomenon,Respiratory Physiological Process,Concept, Respiratory Physiological,Concepts, Respiratory Physiological,Phenomena, Pulmonary Physiological,Phenomena, Respiratory Physiological,Phenomenas, Pulmonary Physiological,Phenomenas, Respiratory Physiological,Phenomenon, Pulmonary Physiological,Phenomenon, Respiratory Physiological,Phenomenons, Pulmonary Physiological,Phenomenons, Respiratory Physiological,Physiologic Processes, Respiratory,Physiological Concept, Respiratory,Physiological Concepts, Respiratory,Physiological Phenomena, Pulmonary,Physiological Phenomena, Respiratory,Physiological Phenomenas, Pulmonary,Physiological Phenomenas, Respiratory,Physiological Phenomenon, Pulmonary,Physiological Phenomenon, Respiratory,Physiological Phenomenons, Pulmonary,Physiological Phenomenons, Respiratory,Physiological Process, Pulmonary,Physiological Process, Respiratory,Physiological Processes, Pulmonary,Physiological Processes, Respiratory,Process, Pulmonary Physiological,Process, Respiratory Physiological,Processes, Pulmonary Physiological,Pulmonary Physiological Phenomenas,Pulmonary Physiological Phenomenons,Respiratory Physiological Concept,Respiratory Physiological Phenomenas,Respiratory Physiological Phenomenons
D002245	Carbon Dioxide	A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.	Carbonic Anhydride,Anhydride, Carbonic,Dioxide, Carbon
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