loaded pressure exhalation valve 50 imitates u201c pursed lip breathing u201d when the patient exhales because backpressure is created by the valves 50 and 18 this backpressure prevents the bronchioles alveoli from collapsing an open airway on exhalation allows for the escape of carbon dioxide reducing the level of that gas in the utser 39 s bloodstream when the exhaled gas escapes through the opening 70 the hyperinflation of the lungs is substantially reduced the device 10 helps emphysema patients in a number of important ways for example the variable pressure valve 50 keeps the airways open preventing the collapse of the alveoli and airways on expiration as a result the air is not trapped in the lungs and hyperinflation of airways is reduced the reduction in hyperinflation allows the user to inspire and exhale more fully thereby delivering the medication 40 to a greater surface of the damaged tissue even further by keeping the alveoli and airways open the exhaled carbon dioxide moves more freely from the lungs into the atmosphere through the openings 70 170 thereby reducing carbon dioxide levels in the user 39 s bloodstream by creating positive backpressure within the conduit reservoir 14 during exhalation the air is not forced into the lungs and stomach of the user on inspiration the backpressure while not forcefully admitting air into the lungs and the stomach of the user expands and keeps open the affected bronchial passages this expansion allows for effective gas exchange as required for normal physiological function of the human body the open air.