ADVANCED PATHOPHYSIOLOGY EXAM
4 QUESTIONS AND ANSWERS 2026
VERIFIED.
Normal Blood Gas Values - ANS pH: 7.35 - 7.45
PaO2: 80 - 100 mmHg
PaCO2: 35 - 45 mmHg
ventilation - ANS ability to clear CO2
oxygenation - ANS the process of delivering oxygen to the blood
causes for CO2 increase - ANS -CO2 is being produced but not being exhaled quickly enough
-increase in CO2 by increased metabolism like fever or exercise
-PaCO2 in ABG is increased therefore pH decreases
-as CO2 accumulates, peripheral and central chemoreceptors signal brain to increase RR
-PaCO2 is influenced by alveolar minute ventilation and CO2 production
-ventilation is influenced by alveolar minute ventilation and Co2 production
-O2 sat decreases because increased CO2 pressure keeps O2 away
alveolar minute ventilation - ANS alveolar volume x RR
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,hypoxemia normal P (A-a) O2
(15-20) - ANS -lungs are working fine but there is problem above airways
-altitude
-nitrogen gas poisoning
-fire smoke (O2 displacement)
Alveolar hypoventilation increased P (A-a) O2
(>20) - ANS not getting enough ventilation into the alveoli, reducing oxygen
-ex. OD antidepressants slowing RR
fixed with O2 and increased ventilation
causes of hypoxemia with increased P - ANS V/Q mismatch
Shunt
Diffusion Defect
V/Q mismatch - ANS areas of our lungs that are receiving ventilation are not matched with
perfused areas.
when there is high CO2, pulmonary vessels selectively vasoconstirct so blood goes where best
work is done
low ventilation but normal perfusion because of airway secretions
somewhat hypoxemic but not as severe as shunt
shunt - ANS extreme VQ mismatch
severe pneumonia
ARDS
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,when alveoli is filled with something that should not be there (fluid, blood, or infection) or
alveoli is collapsed (atelectasis) Very hypoxemic
diffusion defect - ANS conditions where there is a problem in O2 diffusing into the
bloodstream: like with interstitial lung disease, some sort of irritation, body tries to restore
damage, and fibroblasts lines up on the alveolar walls. other examples are pulmonary edema,
hydrostatic pressure is too great, leaking into interstitial space
work of breathing - resistance - ANS pressure that is required to overcome the resistance to
gas flow through the airway during prespiration
clinical conditions that increase airway resistance - ANS COPD
mechanical obstruction
infection
asthma, bronchospasm
work of breathing - compliance - ANS the ability of the lungs to expand is measured as the
lung compliance. The volume change per unit of pressure
when is more muscular effort for work of breathing is required? - ANS lung compliance is
decreased (ex. pulmonary edema)
chest wall compliance is decreased (spinal cord deformity or obesity)
airways are obstructed by bronchospasm of mucous plugging (asthma, bronchitis)
What 5 problems with oxygenation result in hypoxemia? - ANS -O2 concentration of FiO2
-ventilation of the alveoli (hypoventilation)
-V/Q mismatch
-Diffusion Defect
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, -Shunt
Examples of O2 content of FiO2 as a problem with O2 delivery to the alveoli - ANS high
altitudes or oxygen displacement scenarios
Examples of hypoventilation as a problem with O2 delivery to the alveoli -
ANS unconciousness
neurolgoic, muscular or bone diseases that restrict chest expansion
COPD
Examples of VQ mismatch as a problem with diffusion of O2 from the alveoli into the blood -
ANS atelectasis
asthma
chronic bronchitis
pneumonia
ARDS
PE
Examples of diffusion defects as a problem with diffusion of O2 from the alveoli into the blood -
ANS edema
fibrosis
emphysema
examples of shunt as problem with perfusion of pulmonary capillaries - ANS blood flow
bypassing lungs
intracardiac defects
intrapulmonary arteriovenous malformations
@COPYRIGHT ALL RIGHTS RESERVED PAGE 4 OF 40
4 QUESTIONS AND ANSWERS 2026
VERIFIED.
Normal Blood Gas Values - ANS pH: 7.35 - 7.45
PaO2: 80 - 100 mmHg
PaCO2: 35 - 45 mmHg
ventilation - ANS ability to clear CO2
oxygenation - ANS the process of delivering oxygen to the blood
causes for CO2 increase - ANS -CO2 is being produced but not being exhaled quickly enough
-increase in CO2 by increased metabolism like fever or exercise
-PaCO2 in ABG is increased therefore pH decreases
-as CO2 accumulates, peripheral and central chemoreceptors signal brain to increase RR
-PaCO2 is influenced by alveolar minute ventilation and CO2 production
-ventilation is influenced by alveolar minute ventilation and Co2 production
-O2 sat decreases because increased CO2 pressure keeps O2 away
alveolar minute ventilation - ANS alveolar volume x RR
@COPYRIGHT ALL RIGHTS RESERVED PAGE 1 OF 40
,hypoxemia normal P (A-a) O2
(15-20) - ANS -lungs are working fine but there is problem above airways
-altitude
-nitrogen gas poisoning
-fire smoke (O2 displacement)
Alveolar hypoventilation increased P (A-a) O2
(>20) - ANS not getting enough ventilation into the alveoli, reducing oxygen
-ex. OD antidepressants slowing RR
fixed with O2 and increased ventilation
causes of hypoxemia with increased P - ANS V/Q mismatch
Shunt
Diffusion Defect
V/Q mismatch - ANS areas of our lungs that are receiving ventilation are not matched with
perfused areas.
when there is high CO2, pulmonary vessels selectively vasoconstirct so blood goes where best
work is done
low ventilation but normal perfusion because of airway secretions
somewhat hypoxemic but not as severe as shunt
shunt - ANS extreme VQ mismatch
severe pneumonia
ARDS
@COPYRIGHT ALL RIGHTS RESERVED PAGE 2 OF 40
,when alveoli is filled with something that should not be there (fluid, blood, or infection) or
alveoli is collapsed (atelectasis) Very hypoxemic
diffusion defect - ANS conditions where there is a problem in O2 diffusing into the
bloodstream: like with interstitial lung disease, some sort of irritation, body tries to restore
damage, and fibroblasts lines up on the alveolar walls. other examples are pulmonary edema,
hydrostatic pressure is too great, leaking into interstitial space
work of breathing - resistance - ANS pressure that is required to overcome the resistance to
gas flow through the airway during prespiration
clinical conditions that increase airway resistance - ANS COPD
mechanical obstruction
infection
asthma, bronchospasm
work of breathing - compliance - ANS the ability of the lungs to expand is measured as the
lung compliance. The volume change per unit of pressure
when is more muscular effort for work of breathing is required? - ANS lung compliance is
decreased (ex. pulmonary edema)
chest wall compliance is decreased (spinal cord deformity or obesity)
airways are obstructed by bronchospasm of mucous plugging (asthma, bronchitis)
What 5 problems with oxygenation result in hypoxemia? - ANS -O2 concentration of FiO2
-ventilation of the alveoli (hypoventilation)
-V/Q mismatch
-Diffusion Defect
@COPYRIGHT ALL RIGHTS RESERVED PAGE 3 OF 40
, -Shunt
Examples of O2 content of FiO2 as a problem with O2 delivery to the alveoli - ANS high
altitudes or oxygen displacement scenarios
Examples of hypoventilation as a problem with O2 delivery to the alveoli -
ANS unconciousness
neurolgoic, muscular or bone diseases that restrict chest expansion
COPD
Examples of VQ mismatch as a problem with diffusion of O2 from the alveoli into the blood -
ANS atelectasis
asthma
chronic bronchitis
pneumonia
ARDS
PE
Examples of diffusion defects as a problem with diffusion of O2 from the alveoli into the blood -
ANS edema
fibrosis
emphysema
examples of shunt as problem with perfusion of pulmonary capillaries - ANS blood flow
bypassing lungs
intracardiac defects
intrapulmonary arteriovenous malformations
@COPYRIGHT ALL RIGHTS RESERVED PAGE 4 OF 40
