What is hypercapnia typically associated with in terms of blood pH?

• A. Acidosis
• B. Alkalosis
• C. Neutral pH
• D. Normal range

Answer: (A)

Hypercapnia refers to an elevated level of carbon dioxide (CO2) in the blood, which occurs due to inadequate ventilation or impaired gas exchange. When CO2 levels rise, it reacts with water in the body to form carbonic acid, leading to an increase in hydrogen ions and a subsequent decrease in blood pH. This process causes respiratory acidosis, which is characterized by a lower than normal pH in the blood.

Acidosis is a condition where the blood pH is below the normal range of approximately 7.35 to 7.45. In the case of hypercapnia, the accumulation of carbon dioxide directly contributes to this shift in pH towards acidosis. The body attempts to compensate for this by various mechanisms, which may include increased respiratory rate or renal adjustments, but in the acute setting, the immediate effect of hypercapnia is the lowering of blood pH.

In summary, hypercapnia is typically associated with acidosis because the increase in carbon dioxide leads to the formation of carbonic acid, which decreases the pH of the blood.