Renal failure - respiratory acidosis is characterized by which ABG pattern?

Renal failure - respiratory acidosis is characterized by which ABG pattern?

• A. Low pH With Elevated CO2
• B. High pH With Low CO2
• C. Normal pH With Normal CO2
• D. Low pH With Low CO2

Answer: (A)

Respiratory acidosis happens when ventilation is inadequate, so CO2 builds up in the blood. This increased CO2 shifts the acid-base balance toward acidity, lowering the pH. On an arterial blood gas, you’d see a low pH with an elevated PaCO2. In chronic cases, the kidneys try to compensate by retaining bicarbonate to buffer the acid, which can raise the pH toward normal, but the primary pattern remains low pH with high CO2. In renal failure, the first clue is still the elevated CO2 driving acidemia, while impaired kidney function can limit metabolic buffering, making compensation less effective. The other patterns would not fit respiratory acidosis: a high pH with low CO2 is respiratory alkalosis, normal pH with normal CO2 is normal, and a low pH with low CO2 points more to metabolic acidosis with respiratory compensation.

Respiratory acidosis happens when ventilation is inadequate, so CO2 builds up in the blood. This increased CO2 shifts the acid-base balance toward acidity, lowering the pH. On an arterial blood gas, you’d see a low pH with an elevated PaCO2. In chronic cases, the kidneys try to compensate by retaining bicarbonate to buffer the acid, which can raise the pH toward normal, but the primary pattern remains low pH with high CO2. In renal failure, the first clue is still the elevated CO2 driving acidemia, while impaired kidney function can limit metabolic buffering, making compensation less effective. The other patterns would not fit respiratory acidosis: a high pH with low CO2 is respiratory alkalosis, normal pH with normal CO2 is normal, and a low pH with low CO2 points more to metabolic acidosis with respiratory compensation.