Chronic Bronchitis (1 of 2 COPD) Flashcards
chronic bronchitis
inflm –> obstr of a/w
bronchitis
inflamed airways
where does inflm occur first
in large a/w (terminal part of trachea & bronchi) –> small a/w
how does smoking cause chronic bronchitis
smoking –> hypersecretion of mucus –> to inc secretions you need to inc # or size of submucosal glands –> submucosal hypertrophy
submucosal hypertrophy disadvantage
it is initially protective but if persistent will lead to an a/w obstr
etiology
- smoking
- recurring infection
patho
- excess mucus causes mucociliary defenses to be impaired –> microbes & debris trapped in a/w & cannot expectorate –> creates warm & moist enviro for microbes to proliferate –> infection & inflm –> damage to a/w & alveoli
- lumen compromised d/t inflm & obstructed a/w
alveolar damage
alveoli stay empty and no more air can enter –> alveolar collapse –> less SA for gas exchange & dec alveolar ventilation b/c less alveoli are able to participate in gas exchange
alveoli fx
alveoli fill w/ air and perform gas exchange w/ pulmonary capillaries where gas diffuses into capillaries
poor gas exchange is a result of what
dec air apply to the gas exchange surfaces d/t obstruction, not d/t lack of blood flow
normal ventilation:perfusion ratio
V:P = 4.2:5.5 = approx 0.8
what is needed for proper gas exchange
alveoli must fill w/ O2 and blood supply must be sufficient in the pulmonary capillaries
what happens if not enough O2 to alveoli and/or blood supply to pulmonary capillaries
- ventilation:perfusion ratio will not be within normal range
- hypoxemia –> hypoxia
hypoxemia
dec O2 in arterial blood
hypoxia
dec O2 in tissues