Physiology Flashcards
your FEV1/FVC ratio has to be under _% to be diagnosed with COPD
70
why is gas exchange affected in emphysema?
destruction of the alveoli
pulmonary compliance is __creased in emphysema; why?
increased
lose elasticity of tissue so its easier for the lung to expand
emphysematous lungs have a problem with compliance/recoil
recoil
dynamic airway compression is more likely to occur during active expiration/inspiration
active expiration
raising intrapleural pressure which will compress the airways
what chemoreceptors are affected in anxiety?
central
autonomic
2 components of COPD
emphysema and bronchitis
pathophysiology of airways in COPD
fixed airway obstruction and decreased surface area for gas exchange
pathophysiology of airways in fibrosis
reduced pulmonary compliance and impaired gas diffusion
inc alveolar surface tension….
surfactant in newborns
reversible airway obstruction…
asthma
pathophysiology of the SoB in LHF?
reduced pulmonary compliance because of oedema and impaired gas diffusion as a result
according to the O2/haem dissociation curve, how much does O2 need to drop before the Hb drops too
O2 needs to decrease ALOT before Hb decreases
what effect does fibrosis have on an ABG?
affects the diffusion of gases esp oxygen as it thickens the membrane
which diffuses more readily: CO2 or O2?
CO2