Lec 3 - 5 - Pulmonary Mechanics Flashcards
PL is the blank
distending pressure
Pel is the blank
pressure collapsing the lung
Pel and blank are equal and opposite pressures
Pcw pressure of the chest wall
pneumothorax causes blank due to increased pressure from air getting inside chest wall
lung collapse
lung compliance formula
delta v / delta p
low compliance leads to decreased blank
vital capacity
high levels of compliance leads to blank vital capacity such as emphysema
increased
ability of the lung to recoil to resting volume
elastance
increased volume in the lung blank compliance
decreases
surfactant is mostly made of blank
phospholipids
surfactant function by the law of laplace … formula
P = 2T/r
T = surface tension r = radius
without surfactant, the lung volumes would require a greater blank pressure to keep the lung expanded
transmural
fibrosis results in blank recoil
increased
emphysema results in blank recoil
decreased
airway resistance poiseuille’s law formula
R = Ln / r^4
L = length n = viscosity r = radius
upper airway resistance is in blank
series r = r+r+r…
lower airways resistance is blank
parallel = r = 1/r + 1/r….
laminar flow in small airways is blank unlike upper large airways
silent
reynolds number formula which predicts the type of flow that predominates (laminar vs turbulent)
Re = 2rvd / n
r= radius v = velocity of airflow d = air density n = air viscosity
reynolds number greater than 2000 is blank but less than is blank
turbulent flow, laminar flow
flow limitation / equal pressure point?
ok
