18 - Properties of the lung and airway resistance Flashcards
a low compliance of the lungs means that the lungs are
stiff
pulmonary fibrosis causes what
scar forming fibrous connective tissue, reducing compliance of the lungs
what are some factors that can cause pulmonary fibrosis
tuberculosis, pneumonia, long term exposure to irritants
what are the two central concepts in relation to pulmonary elasticity
elastic recoil and compliance
the elasticity of lungs is due to two factors, what are there
pulmonary connective tissue has elastin fibres and THE ALVEOLAR SURFACE TENSION
what is the alveolar surface tension
thin liquid film lines each alveolus, surface tension - attractive force between surface water mols
an increasing alveolar surface tension causes a
decreased compliance of the lungs
what substance counteracts surface tension of water to prevent lung collapse
pulmonary surfactant
what does the pulmonary surfactant do to the compliance
increases it, decreasing the work required to inflate lungs
alveolar surface tension causes the SA to want to be as
small as possible
A decreased size in alveolus due to the alveolar surface tension adds to
elastic recoil
pulmonary surfactant is made of
phospholipoprotein
pulmonary surfactant decreases the tendency of lungs to
recoil which prevents lung collapse
newborn respiratory distress syndrome exists in foetal lungs because
PS is synthesised in late pregnancy
when there is no PS, there is high surface tension, causes alveoli
to collapse
