. If blood gas analysis reveal pH = 7.52, pCO2=3O; pO2= 105.This will be compensated by?
**Core Concept**
The given blood gas analysis reveals a primary respiratory alkalosis, characterized by an elevated pH (7.52), low pCO2 (30), and elevated pO2 (105). The respiratory system compensates for an imbalance by adjusting ventilation rates, but sometimes it cannot fully correct the pH, leading to a compensatory metabolic response.
**Why the Correct Answer is Right**
In this scenario, the respiratory alkalosis is caused by hyperventilation, leading to excessive CO2 loss. However, the kidneys respond by increasing the excretion of bicarbonate ions (HCO3-) to compensate for the alkalosis. This process is mediated by the kidneys' ability to reabsorb ammonium ions (NH4+), which helps to conserve hydrogen ions (H+) and decrease the pH. The compensatory metabolic acidosis is characterized by a decrease in serum bicarbonate levels, which helps to counteract the primary respiratory alkalosis.
**Why Each Wrong Option is Incorrect**
**Option A:** Compensatory respiratory acidosis is incorrect because the primary disorder is respiratory alkalosis, not acidosis. Respiratory acidosis would result from hypoventilation, which is not present in this scenario.
**Option B:** Compensatory respiratory alkalosis is incorrect because the body is trying to compensate for an alkalotic state, not exacerbate it. The respiratory system would not increase ventilation to worsen the alkalosis.
**Option D:** Compensatory metabolic alkalosis is incorrect because the kidneys are trying to correct the alkalosis, not worsen it. The kidneys would increase bicarbonate excretion to decrease the pH, not increase it.
**Clinical Pearl / High-Yield Fact**
A classic exam trap is to confuse compensatory responses with the primary disorder. Remember that the kidneys will compensate for a respiratory alkalosis by increasing bicarbonate excretion, leading to a compensatory metabolic acidosis.
**✓ Correct Answer: C. Compensatory metabolic acidosis**