NUR 242 MED SURG NUR 242 MED SURG
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NUR 242 MED SURG FINAL EXAM 3 UPDATED EXAM WITH
CORRECT QUESTIONS AND ANSWERS.
What is ventilation? - ANS >> the movement of air into and
out of the lungs
What is perfusion? - ANS >> the circulation of blood through
the lungs
What are central chemoreceptors responsive to? -
ANS >> increased H+ in the brain ECF; increased
PaCO2;
"Hypercarbia drive"
,NUR 242 MED SURG NUR 242 MED SURG
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What are peripheral chemoreceptors responsive to? -
ANS >> decreased pH; increased PaCO2; decreased
PaO2; "hypoxic drive"
What are elastic forces? - ANS >> lungs recoil due to elastin,
collagen, fibrin
What are surface forces? - ANS >> surface tension due to
water-air interface
What is airway resistance? - ANS >> opposition to flow
caused by the forces of friction; primarily determined by
airway radius
What is the distensibility of the lungs? - ANS >> ease with
which the lungs can be inflated
What is lung distensibility increased in? - ANS >> neonates
and children; emphysema
,NUR 242 MED SURG NUR 242 MED SURG
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What is lung distensibility decreased in? - ANS >> elderly;
pneumonia, pulmonary edema, ARDS, atelectasis, fibrosis
What is surfactant? - ANS >> complex substance lining the
alveoli and smallest bronchioles containing phospholipids
and a number of apoproteins which reduces surface
tension throughout the lungs, thereby contributing to its
general compliance;
stabilizes the alveoli and keeps them dry
What produces surfactant? - ANS >> produced by the Type II
alveolar cells
What is Ohm's law? - ANS >> velocity = driving
force/resistance
What is Poiseuille law? - ANS >> resistance = (8 x viscosity x
length) / (pi x radius^4)
, NUR 242 MED SURG NUR 242 MED SURG
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What happens if the radius in the lungs goes down? -
ANS >> the resistance goes up
How is the ventilation distributed in the lungs? - ANS >> the
top of the lungs is more distended and less compliant
whereas the lower lung is small and highly compliant
What factors affect lung perfusion? - ANS >> lung
capacitance; low resistance system; flow influenced
by gravity;
resistance primarily determined by vessel radius
What does hypoxia lead to? - ANS >> vasoconstriction of
pulmonary vessels
What does prolong hypoxia lead to? - ANS >> pulmonary
hypertension
What factors affect alveolar-capillary diffusion? -
ANS >> capillary permeability; surface area available
1 | Page
NUR 242 MED SURG FINAL EXAM 3 UPDATED EXAM WITH
CORRECT QUESTIONS AND ANSWERS.
What is ventilation? - ANS >> the movement of air into and
out of the lungs
What is perfusion? - ANS >> the circulation of blood through
the lungs
What are central chemoreceptors responsive to? -
ANS >> increased H+ in the brain ECF; increased
PaCO2;
"Hypercarbia drive"
,NUR 242 MED SURG NUR 242 MED SURG
2 | Page
What are peripheral chemoreceptors responsive to? -
ANS >> decreased pH; increased PaCO2; decreased
PaO2; "hypoxic drive"
What are elastic forces? - ANS >> lungs recoil due to elastin,
collagen, fibrin
What are surface forces? - ANS >> surface tension due to
water-air interface
What is airway resistance? - ANS >> opposition to flow
caused by the forces of friction; primarily determined by
airway radius
What is the distensibility of the lungs? - ANS >> ease with
which the lungs can be inflated
What is lung distensibility increased in? - ANS >> neonates
and children; emphysema
,NUR 242 MED SURG NUR 242 MED SURG
3 | Page
What is lung distensibility decreased in? - ANS >> elderly;
pneumonia, pulmonary edema, ARDS, atelectasis, fibrosis
What is surfactant? - ANS >> complex substance lining the
alveoli and smallest bronchioles containing phospholipids
and a number of apoproteins which reduces surface
tension throughout the lungs, thereby contributing to its
general compliance;
stabilizes the alveoli and keeps them dry
What produces surfactant? - ANS >> produced by the Type II
alveolar cells
What is Ohm's law? - ANS >> velocity = driving
force/resistance
What is Poiseuille law? - ANS >> resistance = (8 x viscosity x
length) / (pi x radius^4)
, NUR 242 MED SURG NUR 242 MED SURG
4 | Page
What happens if the radius in the lungs goes down? -
ANS >> the resistance goes up
How is the ventilation distributed in the lungs? - ANS >> the
top of the lungs is more distended and less compliant
whereas the lower lung is small and highly compliant
What factors affect lung perfusion? - ANS >> lung
capacitance; low resistance system; flow influenced
by gravity;
resistance primarily determined by vessel radius
What does hypoxia lead to? - ANS >> vasoconstriction of
pulmonary vessels
What does prolong hypoxia lead to? - ANS >> pulmonary
hypertension
What factors affect alveolar-capillary diffusion? -
ANS >> capillary permeability; surface area available
