NU201 EXAM 4 Questions And Correct Answers
CO2
HYPOXIC DRIVE:
Normally it is high/increased _____ which drives breathing.
• If there is chronically elevated CO2 due to a disease of the lung (so lungs aren't
working properly to rid oneself of CO2), then CO2 is no longer a stimulus for breathing
• Low O2 (or hypoxia) is the new stimulus/drive for the process of breathing
Hypoxic Drive - what is the stimulus to breathe?
FALSE: For lung disease patients you DO NOT want to bring their O2 sats back up to full
saturation (97-98%)
• Instead you'll want them around 90% or just a bit higher
T/F: For lung disease patients, you want to bring their O2 sats back up to full saturation
(97-98%)
o There will be no drive for the patient to breath and they will stop breathing
What is the consequence to patients with lung disease if you bring their O2 sats up too
high?
• Sudden acute type of dyspnea that occurs in patients with left sided congestive heart
failure which results from pulmonary edema
• Paroxysmal nocturnal dyspnea-acute pulmonary edema when a person is lying
down-because when a person is lying down more blood is able to go back to the heart
,from the lower extremities because gravity is no longer keeping fluid in the legs. Thus,
individuals wake up gasping for air, coughing up frothy sputum that may be blood
tinged.
What is PND?
• fatigue
• lethargy
• muscle weakness
• acid-base imbalance
What is the general s/sx of lung disorders?
• Tachycardia
• When you have low O2 in the tissue/blood, the heart will beat faster in an attempt to
delivery more O2 to the tissue
• Chronic hypoxia, respiratory or cardiovascular disease results in increased
erythropoietin can cause secondary polycythemia
• You can get rid of the secondary polycythemia by giving the patient supplemental O2
How does the body compensate for disorders of the lungs?
• You match ventilation with perfusion (blood flow)
• And you match blood flow with ventilation
• Perfusion Increases = Ventilation Increases
• Perfusion Decreases = Ventilation Decreases
, • So for example:
1. If an alveolus is not being ventilated, the blood vessel near it will constrict therefore
decreasing blood flow to the alveolus .ALSO
2. If blood vessel is occluded, this causes bronchoconstriction so these alveoli will not
be ventilated
• What is the purpose of ventilation-perfusion matching?
1. to maximize/optimize gas exchange in the lungs
2. Why send air to the alveolus if it isn't getting any blood? (just a thinking point)
3. Why send blood to the alveolus if it isn't getting any air? (just a thinking point)
Explain ventilation perfusion matching, why is this concept important?
• Perfusion Increases = Ventilation Increases
• Perfusion Decreases = Ventilation Decreases
With ventilation-perfusion matching, as perfusion increases/ decreases what happens to
ventilation?
3 types:
• Anatomical Deadspace
• Physiological Deadspace
• Alveolar Deadspace
Name the different types of dead space. How many are there?
Anatomical Deadspace
- that part of the respiratory tract, that because of anatomy, is not involved in gas
exchange.
-ex: trachea, primary/secondary/tertiary bronchi, bronchioles.etc
CO2
HYPOXIC DRIVE:
Normally it is high/increased _____ which drives breathing.
• If there is chronically elevated CO2 due to a disease of the lung (so lungs aren't
working properly to rid oneself of CO2), then CO2 is no longer a stimulus for breathing
• Low O2 (or hypoxia) is the new stimulus/drive for the process of breathing
Hypoxic Drive - what is the stimulus to breathe?
FALSE: For lung disease patients you DO NOT want to bring their O2 sats back up to full
saturation (97-98%)
• Instead you'll want them around 90% or just a bit higher
T/F: For lung disease patients, you want to bring their O2 sats back up to full saturation
(97-98%)
o There will be no drive for the patient to breath and they will stop breathing
What is the consequence to patients with lung disease if you bring their O2 sats up too
high?
• Sudden acute type of dyspnea that occurs in patients with left sided congestive heart
failure which results from pulmonary edema
• Paroxysmal nocturnal dyspnea-acute pulmonary edema when a person is lying
down-because when a person is lying down more blood is able to go back to the heart
,from the lower extremities because gravity is no longer keeping fluid in the legs. Thus,
individuals wake up gasping for air, coughing up frothy sputum that may be blood
tinged.
What is PND?
• fatigue
• lethargy
• muscle weakness
• acid-base imbalance
What is the general s/sx of lung disorders?
• Tachycardia
• When you have low O2 in the tissue/blood, the heart will beat faster in an attempt to
delivery more O2 to the tissue
• Chronic hypoxia, respiratory or cardiovascular disease results in increased
erythropoietin can cause secondary polycythemia
• You can get rid of the secondary polycythemia by giving the patient supplemental O2
How does the body compensate for disorders of the lungs?
• You match ventilation with perfusion (blood flow)
• And you match blood flow with ventilation
• Perfusion Increases = Ventilation Increases
• Perfusion Decreases = Ventilation Decreases
, • So for example:
1. If an alveolus is not being ventilated, the blood vessel near it will constrict therefore
decreasing blood flow to the alveolus .ALSO
2. If blood vessel is occluded, this causes bronchoconstriction so these alveoli will not
be ventilated
• What is the purpose of ventilation-perfusion matching?
1. to maximize/optimize gas exchange in the lungs
2. Why send air to the alveolus if it isn't getting any blood? (just a thinking point)
3. Why send blood to the alveolus if it isn't getting any air? (just a thinking point)
Explain ventilation perfusion matching, why is this concept important?
• Perfusion Increases = Ventilation Increases
• Perfusion Decreases = Ventilation Decreases
With ventilation-perfusion matching, as perfusion increases/ decreases what happens to
ventilation?
3 types:
• Anatomical Deadspace
• Physiological Deadspace
• Alveolar Deadspace
Name the different types of dead space. How many are there?
Anatomical Deadspace
- that part of the respiratory tract, that because of anatomy, is not involved in gas
exchange.
-ex: trachea, primary/secondary/tertiary bronchi, bronchioles.etc
