PCCN Review - Pulmonary questions as
given by the AACN Latest 2026 questions
and answers
At higher altitudes, there is decreased atmospheric pressure to force oxygen into
the lungs. To compensate for the lower pressure, the person must breathe faster.
The percentage of oxygen remains the same, but the partial pressure of the
oxygen decreases. Aterial PaO2 decreases, as does O2 saturation. The rapid
breathing will result in hyperventillation, raising the pH and lowering the PaCO2
level.
SaO2 values account for what % of O2 carreid within the bloodstream?
-2-3%
-10-24%
-97-98%
-100% - ANSWER-97-98%
The % of total oxygen carried within the bloodstream attributed to the SaO2 is 97-
98%.
SaO2 is the arterial saturation of hemoglobin. The % corresponds to the % of
hemoglobin on the red blood cells that carries O2. Typically this % is documented
as normal when within 93-99%.
PaO2 is the % of O2 within the bloodstream that is free or dissolved in the plasma.
This value is documented in mmHg and is considered normal when within the
,range of 80-100 mmHg.
,Hypoxemia is best defined as:
-A decrease in O2 at the cellular level
-A decrease in O2 levels in arterial blood
-A decrease in O2 levels in venous blood
-A decrease in O2 levels from the brain - ANSWER-A decrease in O2 levels in
arterial blood
Hypoxemia is a decrease in O2 levels in arterial blood or PaO2 < 80 mmHg.
Hypoxia is defined as a decreased oxygen level at the cellular level.
Decreased O2 levels within veins refer to PaO2 < 50mmHg
Decreased O2 levels within the brain refer to ScVO2 < 20
Your patient has been diagnosed with pulmonary HTN. Which of the following
compensatory mechanisms would be expected if the patient suffered from
chronic hypoxia?
-Polycythemia
-Hypoplasia of the pulmonary vasculature
-Thinning of blood vessels in the lungs
-Cor pulmonale - ANSWER-Polycythemia
Effects of acute hypoxia are reversible.
, Chronic hypoxia causes permanent changes in the lungs and pulmonary
vasculature (hyperplasia and hypertrophy). This will cause thickening of the blood
vessels and will narrow the lumen.
Polycythemia develops and the blood viscosity increases. The increased number
of cells will be available to carry O2 but the increased viscosity will increase
pressure in the pulmonary vasculature and force the right ventricle to pump
harder to maintain the CO level. The right venticle will hypertrophy and eventually
weaken, and the patient will develop right heart failure (cor pulmonale).
Type II alveolar cells produce:
-Macrocytes
-Phagocytes
-Surfactant
-CO2 - ANSWER-Surfactant
Surfactant is a lipoprotein that functions by increasing surface tension of alveoli
and allow alveoli to expand and contract. Some residual pressure should be
present in the alveoli at the end of respiration to keep the alveoli open
(physiologic PEEP). If surfactant production is impaired, the alveoli's ability to
exchange O2 is compromised.
Type I cells line the outside of the alveoli.
If you hear faint breath sounds on the left side of the chest and normal sounds on
the right side immediately after your patient is intubated, most likely:
given by the AACN Latest 2026 questions
and answers
At higher altitudes, there is decreased atmospheric pressure to force oxygen into
the lungs. To compensate for the lower pressure, the person must breathe faster.
The percentage of oxygen remains the same, but the partial pressure of the
oxygen decreases. Aterial PaO2 decreases, as does O2 saturation. The rapid
breathing will result in hyperventillation, raising the pH and lowering the PaCO2
level.
SaO2 values account for what % of O2 carreid within the bloodstream?
-2-3%
-10-24%
-97-98%
-100% - ANSWER-97-98%
The % of total oxygen carried within the bloodstream attributed to the SaO2 is 97-
98%.
SaO2 is the arterial saturation of hemoglobin. The % corresponds to the % of
hemoglobin on the red blood cells that carries O2. Typically this % is documented
as normal when within 93-99%.
PaO2 is the % of O2 within the bloodstream that is free or dissolved in the plasma.
This value is documented in mmHg and is considered normal when within the
,range of 80-100 mmHg.
,Hypoxemia is best defined as:
-A decrease in O2 at the cellular level
-A decrease in O2 levels in arterial blood
-A decrease in O2 levels in venous blood
-A decrease in O2 levels from the brain - ANSWER-A decrease in O2 levels in
arterial blood
Hypoxemia is a decrease in O2 levels in arterial blood or PaO2 < 80 mmHg.
Hypoxia is defined as a decreased oxygen level at the cellular level.
Decreased O2 levels within veins refer to PaO2 < 50mmHg
Decreased O2 levels within the brain refer to ScVO2 < 20
Your patient has been diagnosed with pulmonary HTN. Which of the following
compensatory mechanisms would be expected if the patient suffered from
chronic hypoxia?
-Polycythemia
-Hypoplasia of the pulmonary vasculature
-Thinning of blood vessels in the lungs
-Cor pulmonale - ANSWER-Polycythemia
Effects of acute hypoxia are reversible.
, Chronic hypoxia causes permanent changes in the lungs and pulmonary
vasculature (hyperplasia and hypertrophy). This will cause thickening of the blood
vessels and will narrow the lumen.
Polycythemia develops and the blood viscosity increases. The increased number
of cells will be available to carry O2 but the increased viscosity will increase
pressure in the pulmonary vasculature and force the right ventricle to pump
harder to maintain the CO level. The right venticle will hypertrophy and eventually
weaken, and the patient will develop right heart failure (cor pulmonale).
Type II alveolar cells produce:
-Macrocytes
-Phagocytes
-Surfactant
-CO2 - ANSWER-Surfactant
Surfactant is a lipoprotein that functions by increasing surface tension of alveoli
and allow alveoli to expand and contract. Some residual pressure should be
present in the alveoli at the end of respiration to keep the alveoli open
(physiologic PEEP). If surfactant production is impaired, the alveoli's ability to
exchange O2 is compromised.
Type I cells line the outside of the alveoli.
If you hear faint breath sounds on the left side of the chest and normal sounds on
the right side immediately after your patient is intubated, most likely:
