What happens to PaCO2 and pH levels in a patient experiencing respiratory acidosis?

In respiratory acidosis, there is an accumulation of carbon dioxide (CO2) in the blood due to impaired ventilation. This increase in carbon dioxide leads to an increase in the concentration of carbonic acid (H2CO3), which subsequently dissociates to release hydrogen ions (H+). As the hydrogen ions increase, the pH of the blood decreases, resulting in a more acidic environment.

The key points are:

• The increase in PaCO2 is a direct result of the inadequate removal of CO2 from the lungs, whether due to conditions like chronic obstructive pulmonary disease (COPD), respiratory depression, or other factors that impair gas exchange.

• As a consequence of the raised PaCO2, the pH level drops, confirming the acidosis.

These changes highlight a fundamental aspect of respiratory physiology, where the regulation of CO2 levels is crucial in maintaining acid-base balance. In respiratory acidosis, both the elevated PaCO2 and the decreased pH clearly indicate a shift toward acidity in the bloodstream.