NSER 7110 FINAL EXAM COMPLETE QUESTIONS WITH
100% VERIFIED ANSWERS
1. A patient presents with the following ABG results: pH 7.25, CO2 50,
HCO3 24, pO2 70, SaO2 91%. What is the correct interpretation?
A) Uncompensated respiratory acidosis with mild hypoxemia
B) Partially compensated respiratory acidosis with mild hypoxemia
C) Fully compensated respiratory acidosis with moderate hypoxemia
D) Uncompensated metabolic acidosis with no hypoxemia
Correct Answer: A) Uncompensated respiratory acidosis with mild
hypoxemia
Rationale: The pH is low (7.25) indicating acidosis. The CO2 is elevated
(50) indicating a respiratory cause. The HCO3 is normal (24) showing no
renal compensation has occurred yet. The pO2 of 70 indicates mild
hypoxemia (60-80 mmHg).
2. Which buffer system is the most important rapid-acting buffer in
the body?
A) Protein buffer system
B) Phosphate buffer system
C) Hemoglobin buffer system
D) Bicarbonate-carbonic acid buffer system
Correct Answer: D) Bicarbonate-carbonic acid buffer system
,Rationale: The bicarbonate-carbonic acid buffer system is the most
important rapid-acting buffer in the body. It operates in the
extracellular fluid and can respond to pH changes within seconds to
minutes.
3. A patient has the following ABG results: pH 7.32, CO2 28, HCO3 16,
pO2 82, SaO2 95%. What is the primary acid-base disorder?
A) Respiratory acidosis
B) Respiratory alkalosis
C) Metabolic acidosis
D) Metabolic alkalosis
Correct Answer: C) Metabolic acidosis
Rationale: The pH is low (7.32) indicating acidosis. The HCO3 is
decreased (16) indicating a metabolic cause (bicarbonate loss). The CO2
is low (28) as a compensatory response. The pO2 and SaO2 are normal
indicating no hypoxemia.
4. A patient with diabetic ketoacidosis would most likely present with
which ABG pattern?
A) pH 7.50, CO2 45, HCO3 30
B) pH 7.25, CO2 35, HCO3 15
C) pH 7.35, CO2 55, HCO3 28
D) pH 7.45, CO2 30, HCO3 22
Correct Answer: B) pH 7.25, CO2 35, HCO3 15
,Rationale: DKA produces metabolic acidosis from ketone body
accumulation. The pH would be low, HCO3 low (from buffering acids),
and CO2 low as compensatory hyperventilation attempts to blow off
CO2.
5. Which of the following is a cause of respiratory acidosis?
A) Hyperventilation syndrome
B) Pulmonary embolism
C) COPD exacerbation
D) Salicylate toxicity
Correct Answer: C) COPD exacerbation
Rationale: COPD causes impaired gas exchange and CO2 retention
leading to respiratory acidosis. Hyperventilation syndrome and
salicylate toxicity cause respiratory alkalosis. Pulmonary embolism
typically causes respiratory alkalosis from hyperventilation.
6. A patient with severe anxiety and hyperventilation would have
which ABG result?
A) pH 7.50, CO2 28, HCO3 24
B) pH 7.28, CO2 48, HCO3 22
C) pH 7.36, CO2 35, HCO3 18
D) pH 7.42, CO2 42, HCO3 28
Correct Answer: A) pH 7.50, CO2 28, HCO3 24
, Rationale: Hyperventilation blows off CO2 leading to respiratory
alkalosis. The pH would be elevated, CO2 decreased, and HCO3 would
be normal initially (uncompensated).
7. In metabolic alkalosis, which compensatory mechanism would you
expect?
A) Increased respiratory rate to eliminate CO2
B) Decreased respiratory rate to retain CO2
C) Renal retention of bicarbonate
D) Renal excretion of hydrogen ions
Correct Answer: B) Decreased respiratory rate to retain CO2
Rationale: In metabolic alkalosis, the body attempts to compensate by
hypoventilating to retain CO2, which forms carbonic acid to lower the
pH back toward normal.
8. Which of the following indicates full compensation in an acid-base
disturbance?
A) pH is abnormal, CO2 and HCO3 are abnormal
B) pH is normal, CO2 and HCO3 are abnormal
C) pH is normal, CO2 and HCO3 are normal
D) pH is abnormal, CO2 is normal, HCO3 is abnormal
Correct Answer: B) pH is normal, CO2 and HCO3 are abnormal
Rationale: Full compensation occurs when the pH has returned to
normal range (7.35-7.45) but the compensatory mechanisms (CO2
and/or HCO3) remain abnormal as they work to maintain homeostasis.
100% VERIFIED ANSWERS
1. A patient presents with the following ABG results: pH 7.25, CO2 50,
HCO3 24, pO2 70, SaO2 91%. What is the correct interpretation?
A) Uncompensated respiratory acidosis with mild hypoxemia
B) Partially compensated respiratory acidosis with mild hypoxemia
C) Fully compensated respiratory acidosis with moderate hypoxemia
D) Uncompensated metabolic acidosis with no hypoxemia
Correct Answer: A) Uncompensated respiratory acidosis with mild
hypoxemia
Rationale: The pH is low (7.25) indicating acidosis. The CO2 is elevated
(50) indicating a respiratory cause. The HCO3 is normal (24) showing no
renal compensation has occurred yet. The pO2 of 70 indicates mild
hypoxemia (60-80 mmHg).
2. Which buffer system is the most important rapid-acting buffer in
the body?
A) Protein buffer system
B) Phosphate buffer system
C) Hemoglobin buffer system
D) Bicarbonate-carbonic acid buffer system
Correct Answer: D) Bicarbonate-carbonic acid buffer system
,Rationale: The bicarbonate-carbonic acid buffer system is the most
important rapid-acting buffer in the body. It operates in the
extracellular fluid and can respond to pH changes within seconds to
minutes.
3. A patient has the following ABG results: pH 7.32, CO2 28, HCO3 16,
pO2 82, SaO2 95%. What is the primary acid-base disorder?
A) Respiratory acidosis
B) Respiratory alkalosis
C) Metabolic acidosis
D) Metabolic alkalosis
Correct Answer: C) Metabolic acidosis
Rationale: The pH is low (7.32) indicating acidosis. The HCO3 is
decreased (16) indicating a metabolic cause (bicarbonate loss). The CO2
is low (28) as a compensatory response. The pO2 and SaO2 are normal
indicating no hypoxemia.
4. A patient with diabetic ketoacidosis would most likely present with
which ABG pattern?
A) pH 7.50, CO2 45, HCO3 30
B) pH 7.25, CO2 35, HCO3 15
C) pH 7.35, CO2 55, HCO3 28
D) pH 7.45, CO2 30, HCO3 22
Correct Answer: B) pH 7.25, CO2 35, HCO3 15
,Rationale: DKA produces metabolic acidosis from ketone body
accumulation. The pH would be low, HCO3 low (from buffering acids),
and CO2 low as compensatory hyperventilation attempts to blow off
CO2.
5. Which of the following is a cause of respiratory acidosis?
A) Hyperventilation syndrome
B) Pulmonary embolism
C) COPD exacerbation
D) Salicylate toxicity
Correct Answer: C) COPD exacerbation
Rationale: COPD causes impaired gas exchange and CO2 retention
leading to respiratory acidosis. Hyperventilation syndrome and
salicylate toxicity cause respiratory alkalosis. Pulmonary embolism
typically causes respiratory alkalosis from hyperventilation.
6. A patient with severe anxiety and hyperventilation would have
which ABG result?
A) pH 7.50, CO2 28, HCO3 24
B) pH 7.28, CO2 48, HCO3 22
C) pH 7.36, CO2 35, HCO3 18
D) pH 7.42, CO2 42, HCO3 28
Correct Answer: A) pH 7.50, CO2 28, HCO3 24
, Rationale: Hyperventilation blows off CO2 leading to respiratory
alkalosis. The pH would be elevated, CO2 decreased, and HCO3 would
be normal initially (uncompensated).
7. In metabolic alkalosis, which compensatory mechanism would you
expect?
A) Increased respiratory rate to eliminate CO2
B) Decreased respiratory rate to retain CO2
C) Renal retention of bicarbonate
D) Renal excretion of hydrogen ions
Correct Answer: B) Decreased respiratory rate to retain CO2
Rationale: In metabolic alkalosis, the body attempts to compensate by
hypoventilating to retain CO2, which forms carbonic acid to lower the
pH back toward normal.
8. Which of the following indicates full compensation in an acid-base
disturbance?
A) pH is abnormal, CO2 and HCO3 are abnormal
B) pH is normal, CO2 and HCO3 are abnormal
C) pH is normal, CO2 and HCO3 are normal
D) pH is abnormal, CO2 is normal, HCO3 is abnormal
Correct Answer: B) pH is normal, CO2 and HCO3 are abnormal
Rationale: Full compensation occurs when the pH has returned to
normal range (7.35-7.45) but the compensatory mechanisms (CO2
and/or HCO3) remain abnormal as they work to maintain homeostasis.
