ATI TEAS (Test of Essential Academic Skills) Version 7ScienceMedium
A nurse is reviewing a patient's arterial blood gas (ABG) results. The pH is 7.28, PaCO2 is 55 mmHg, and HCO3- is 24 mEq/L. Based on these values, which acid-base imbalance is the patient experiencing?
- ARespiratory alkalosis
- BMetabolic acidosis
- CMetabolic alkalosis
- DRespiratory acidosis
Show answer & explanationAnswer & explanation
Correct answer: D. Respiratory acidosis
A pH of 7.28 indicates acidosis (normal 7.35-7.45). A PaCO2 of 55 mmHg indicates hypercapnia (normal 35-45 mmHg), which is a respiratory cause of acidosis. An HCO3- of 24 mEq/L is within the normal range (22-26 mEq/L), indicating the primary problem is not metabolic. Therefore, the patient is experiencing respiratory acidosis.
Why the other options are wrong
- A. Respiratory alkalosis would involve a high pH and a low PaCO2, opposite of these findings.
- B. Metabolic acidosis would involve a low pH and a low HCO3-, which is not seen here.
- C. Metabolic alkalosis would involve a high pH and a high HCO3-, which is not seen here.
Acid-Base Imbalance
A condition in which the body's pH balance is disrupted, often due to respiratory or metabolic issues affecting carbon dioxide (acid) or bicarbonate (base) levels.
- Normal pH: 7.35-7.45.
- Normal PaCO2: 35-45 mmHg (respiratory component).
- Normal HCO3-: 22-26 mEq/L (metabolic component).
Memory trick: ROME: Respiratory Opposite, Metabolic Equal.