Compensation Mechanisms

The body has compensatory mechanisms to counter the changes in blood pH that cause acidosis  or alkalosis.

Respiratory compensation responds to metabolic acidosis or alkalosis.

Metabolic acidosis triggers hyperventilation, resulting in rapid elimination of carbon dioxide.

This reduces the production of carbonic acid and its subsequent dissociation into hydrogen and bicarbonate ions, raising the pH.

Respiratory compensation for metabolic alkalosis involves slow, shallow breathing, which allows carbon dioxide to accumulate in the blood. This leads to the formation of more carbonic acid and, in turn, the release of more hydrogen ions, decreasing the pH.

Renal compensation responds to respiratory acidosis or alkalosis.

During respiratory acidosis, the kidneys retain bicarbonate ions to buffer the excess hydrogen ions, helping to restore pH balance.

During alkalosis, the kidneys decrease hydrogen ion secretion and increase bicarbonate ion excretion, lowering blood bicarbonate concentration.

This reduction in bicarbonate, combined with the retention of hydrogen ions due to decreased secretion, contributes to a lower blood pH, helping to restore balance.