ABG Quiz
Questions: 16 · 10 minutes
1. Which ABG value most directly represents the metabolic component used in routine acid-base interpretation?
HCO₃⁻
PaCO₂
PaO₂
Oxygen saturation
2. Which ABG value primarily represents the respiratory component of acid-base balance?
PaCO₂
HCO₃⁻
PaO₂
Base excess
3. Using Winter's formula, what PaCO₂ range is expected when HCO₃⁻ is 12 mEq/L in metabolic acidosis?
12-16 mmHg
36-40 mmHg
48-52 mmHg
24-28 mmHg
4. A patient has pH 7.28, PaCO₂ 55 mmHg, and HCO₃⁻ 24 mEq/L. Which interpretation best fits this pattern?
Primary respiratory alkalosis with metabolic compensation
Primary metabolic acidosis with respiratory compensation
Primary respiratory acidosis with little or no metabolic compensation
Primary metabolic alkalosis with respiratory compensation
5. An ABG reports pH 7.36, PaCO₂ 52 mmHg, and HCO₃⁻ 29 mEq/L. Which interpretation best accounts for all three values?
No acid-base disturbance because the pH is within range
Metabolic acidosis with respiratory compensation
Mixed respiratory and metabolic alkalosis
Respiratory acidosis with metabolic compensation
6. An ABG shows pH 7.25, PaCO₂ 32 mmHg, and HCO₃⁻ 17 mEq/L. Which interpretation is most appropriate?
Respiratory acidosis with metabolic compensation
Metabolic acidosis with respiratory compensation
Respiratory alkalosis without compensation
Metabolic alkalosis with respiratory compensation
7. An ABG shows pH 7.10, PaCO₂ 60 mmHg, and HCO₃⁻ 18 mEq/L. Which interpretation best explains the results?
Mixed respiratory and metabolic acidosis
Respiratory acidosis with appropriate metabolic compensation
Metabolic acidosis with appropriate respiratory compensation
Mixed respiratory and metabolic alkalosis
8. Which measurement specifically requires arterial blood when the goal is to directly determine arterial oxygen tension?
PaO₂
Calculated anion gap
Blood glucose concentration
Serum lactate concentration
9. An ABG shows pH 7.40, PaCO₂ 20 mmHg, and HCO₃⁻ 12 mEq/L. What is the best conclusion?
The ABG is normal because the pH is 7.40
A mixed metabolic acidosis and respiratory alkalosis is likely
The values indicate isolated metabolic alkalosis
The values indicate isolated respiratory acidosis
10. An ABG shows pH 7.52, PaCO₂ 28 mmHg, and HCO₃⁻ 23 mEq/L. What is the primary disturbance?
Metabolic alkalosis
Respiratory acidosis
Respiratory alkalosis
Metabolic acidosis
11. A patient with prolonged vomiting has pH 7.55, PaCO₂ 50 mmHg, and HCO₃⁻ 42 mEq/L. What does the elevated PaCO₂ most likely represent?
A primary respiratory acidosis causing the alkalemia
An additional respiratory alkalosis
Failure of the kidneys to retain bicarbonate
Respiratory compensation for metabolic alkalosis
12. A patient with metabolic acidosis has pH 7.20, PaCO₂ 20 mmHg, and HCO₃⁻ 8 mEq/L. Winter's formula gives an expected PaCO₂ of about 20 ± 2 mmHg. What does the measured PaCO₂ indicate?
An additional respiratory acidosis
An additional respiratory alkalosis
Appropriate respiratory compensation
Absence of a metabolic disturbance
13. An ABG shows pH 7.44, PaCO₂ 30 mmHg, and HCO₃⁻ 20 mEq/L. Which pattern is most likely?
Metabolic acidosis with respiratory compensation
Respiratory acidosis with metabolic compensation
Respiratory alkalosis with metabolic compensation
Metabolic alkalosis without compensation
14. A sample has pH 7.49, PaCO₂ 44 mmHg, and HCO₃⁻ 31 mEq/L. Which pattern does it most strongly suggest?
Respiratory alkalosis with metabolic compensation
Metabolic alkalosis with respiratory compensation
Respiratory acidosis without compensation
Mixed respiratory and metabolic acidosis
15. Which range is generally considered normal for arterial blood pH?
7.30-7.50
7.25-7.35
7.45-7.55
7.35-7.45
16. An ABG reports a pH of 7.29. How should the pH be classified before considering the other values?
Within the usual reference range
Acidemic
Fully compensated
Alkalemic