Biomaterial Database

CO2 rebreathing during BiPAP ventilatory assistance. 1995

G T Ferguson, and M Gilmartin

Department of Medicine, University of Colorado Health Sciences Center, National Jewish Center for Immunology and Respiratory Medicine, Denver, Colorado.

BiPAP ventilatory assistance can increase minute ventilation and reduce respiratory effort, but does not always reduce PaCO2. We studied the effects of BiPAP ventilatory assistance on PaCO2 and examined specific mechanisms whereby BiPAP ventilatory assistance may not lower PaCO2. BiPAP ventilatory assistance using a non-rebreather valve and volume cycled ventilation at similar settings produced significantly lower PaCO2 than BiPAP ventilatory assistance using a standard exhalation device. The failure of PaCO2 to fall with the standard exhalation device was due to exhalation past the exhalation device into the ventilator tubing, subsequent rebreathing of the exhaled gases, and an increase in dead space ventilation. Use of other fixed-resistance exhalation devices also resulted in exhalation back into the ventilator tubing. Use of a new plateau exhalation device or a non-rebreather valve eliminated CO2 rebreathing and its effect on dead space ventilation. Changing exhalation devices had no significant effect on BiPAP pressure generation or sensing capabilities. Our results indicate that the use of a standard exhalation device during BiPAP ventilatory assistance causes CO2 rebreathing, which can blunt any effect of BiPAP on PaCO2. Use of an appropriate alternative exhalation device can eliminate this problem.

UI	MeSH Term	Description	Entries
D008173	Lung Diseases, Obstructive	Any disorder marked by obstruction of conducting airways of the lung. AIRWAY OBSTRUCTION may be acute, chronic, intermittent, or persistent.	Obstructive Lung Diseases,Obstructive Pulmonary Diseases,Lung Disease, Obstructive,Obstructive Lung Disease,Obstructive Pulmonary Disease,Pulmonary Disease, Obstructive,Pulmonary Diseases, Obstructive
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
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
D012131	Respiratory Insufficiency	Failure to adequately provide oxygen to cells of the body and to remove excess carbon dioxide from them. (Stedman, 25th ed)	Acute Hypercapnic Respiratory Failure,Acute Hypoxemic Respiratory Failure,Hypercapnic Acute Respiratory Failure,Hypercapnic Respiratory Failure,Hypoxemic Acute Respiratory Failure,Hypoxemic Respiratory Failure,Respiratory Depression,Respiratory Failure,Ventilatory Depression,Depressions, Ventilatory,Failure, Hypercapnic Respiratory,Failure, Hypoxemic Respiratory,Failure, Respiratory,Hypercapnic Respiratory Failures,Hypoxemic Respiratory Failures,Respiratory Failure, Hypercapnic,Respiratory Failure, Hypoxemic,Respiratory Failures
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
D002908	Chronic Disease	Diseases which have one or more of the following characteristics: they are permanent, leave residual disability, are caused by nonreversible pathological alteration, require special training of the patient for rehabilitation, or may be expected to require a long period of supervision, observation, or care (Dictionary of Health Services Management, 2d ed). For epidemiological studies chronic disease often includes HEART DISEASES; STROKE; CANCER; and diabetes (DIABETES MELLITUS, TYPE 2).	Chronic Condition,Chronic Illness,Chronically Ill,Chronic Conditions,Chronic Diseases,Chronic Illnesses,Condition, Chronic,Disease, Chronic,Illness, Chronic
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
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
D013990	Tidal Volume	The volume of air inspired or expired during each normal, quiet respiratory cycle. Common abbreviations are TV or V with subscript T.	Tidal Volumes,Volume, Tidal,Volumes, Tidal