Biomaterial Database

Inspired oxygen concentrations during positive pressure therapy. 2004

Elizabeth A Yoder, and Kenneth Klann, and Kingman P Strohl

Louis Stokes Cleveland DVA Medical Center, Medical Service, Center for Sleep Disorders Research, Case Western Reserve University, Cleveland, Ohio, USA. Beth.Yoder@att.net

OBJECTIVE This study examined the effects of various factors that might influence the fraction of oxygen in inspired air (FiO (2)) in a human and in a model system during nasal positive pressure treatments. METHODS A healthy male volunteer and a mannequin head were each outfitted with a nasal continuous positive air pressure mask and pressure source (BiPAP S, Respironics, Murrysville, PA). Oxygen was added through either a side port in the mask or a port near the machine. Flow and FiO (2) were measured while varying inspiratory and expiratory pressures. Measurements were repeated with a leak added to the system and using different sites of oxygen administration. RESULTS In both the human and in the model system, increasing inspiratory pressure, thereby increasing flow, decreased FiO (2) inside the mask. In the model system, addition of a fixed leak caused an increase in flow and decrease in FiO (2) at any given level of inspiratory and expiratory pressure. CONCLUSIONS In patients using nasal positive pressure therapy, variables of pressure, leak around the mask, and the site of oxygen delivery determine the inspired oxygen concentration when giving oxygen supplementation.

UI	MeSH Term	Description	Entries
D008297	Male		Males
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
D010101	Oxygen Consumption	The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)	Consumption, Oxygen,Consumptions, Oxygen,Oxygen Consumptions
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
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001239	Inhalation	The act of BREATHING in.	Inhaling,Inspiration, Respiratory,Respiratory Inspiration
D012891	Sleep Apnea Syndromes	Disorders characterized by multiple cessations of respirations during sleep that induce partial arousals and interfere with the maintenance of sleep. Sleep apnea syndromes are divided into central (see SLEEP APNEA, CENTRAL), obstructive (see SLEEP APNEA, OBSTRUCTIVE), and mixed central-obstructive types.	Apnea, Sleep,Hypersomnia with Periodic Respiration,Sleep-Disordered Breathing,Mixed Central and Obstructive Sleep Apnea,Sleep Apnea, Mixed,Sleep Apnea, Mixed Central and Obstructive,Sleep Hypopnea,Apnea Syndrome, Sleep,Apnea Syndromes, Sleep,Apneas, Sleep,Breathing, Sleep-Disordered,Hypopnea, Sleep,Hypopneas, Sleep,Mixed Sleep Apnea,Mixed Sleep Apneas,Sleep Apnea,Sleep Apnea Syndrome,Sleep Apneas,Sleep Apneas, Mixed,Sleep Disordered Breathing,Sleep Hypopneas
D045422	Continuous Positive Airway Pressure	A technique of respiratory therapy, in either spontaneously breathing or mechanically ventilated patients, in which airway pressure is maintained above atmospheric pressure throughout the respiratory cycle by pressurization of the ventilatory circuit. (On-Line Medical Dictionary [Internet]. Newcastle upon Tyne(UK): The University Dept. of Medical Oncology: The CancerWEB Project; c1997-2003 [cited 2003 Apr 17]. Available from: http://cancerweb.ncl.ac.uk/omd/)	Airway Pressure Release Ventilation,BiPAP Bilevel Positive Airway Pressure,BiPAP Biphasic Positive Airway Pressure,Bilevel Positive Airway Pressure,Biphasic Positive Airway Pressure,APRV Ventilation Mode,Bilevel Continuous Positive Airway Pressure,Biphasic Continuous Positive Airway Pressure,CPAP Ventilation,Nasal Continuous Positive Airway Pressure,nCPAP Ventilation,APRV Ventilation Modes,Ventilation Mode, APRV,Ventilation Modes, APRV,Ventilation, CPAP,Ventilation, nCPAP