Which metabolic disturbance is characterized by a decrease in bicarbonate levels?

Metabolic acidosis is characterized by a decrease in bicarbonate levels. In this condition, the body experiences an accumulation of acids or a significant loss of bicarbonate, leading to a decrease in blood pH. The bicarbonate (HCO3-) acts as a buffer in the blood, and lower levels indicate that the buffering capacity is overwhelmed by either increased acid production—such as in cases of lactic acidosis or ketoacidosis—or by prolonged diarrhea, which results in the loss of bicarbonate.

The kidneys and lungs play crucial roles in compensating for changes in acid-base balance. In metabolic acidosis, respiratory compensation may occur, where the respiratory rate increases to blow off carbon dioxide, thus attempting to raise blood pH back to normal levels. Consequently, understanding the biochemical processes and compensatory mechanisms of metabolic acidosis is vital in critical care, as these patients often present with varying degrees of respiratory distress alongside their metabolic derangement.