Respiratory compensation is the modulation by the brainstem respiratory centers, which involves altering alveolar ventilation to try and bring the plasma pH back to its normal value (7.4) in order to keep the acid-base balance in the body. It usually occurs within minutes to hours and is much faster than

renal compensation Renal compensation is a mechanism by which the kidneys can regulate the plasma pH. It is slower than respiratory compensation, but has a greater ability to restore normal values. In respiratory acidosis, the kidney produces and excretes ammonium ...

(takes several days), but has less ability to restore normal values. In

metabolic acidosis Metabolic acidosis is a serious electrolyte disorder characterized by an imbalance in the body's acid-base balance. Metabolic acidosis has three main root causes: increased acid production, loss of bicarbonate, and a reduced ability of the kidneys ...

chemoreceptors A chemoreceptor, also known as chemosensor, is a specialized sensory receptor which transduces a chemical substance ( endogenous or induced) to generate a biological signal. This signal may be in the form of an action potential, if the chemorec ...

sense a deranged acid-base balance with a plasma pH of lesser than normal (<7.4). The chemoreceptors send afferent fibers to the brainstem respiratory centers. The brainstem respiratory centers increase alveolar ventilation ( hyperventilation) so that

carbon dioxide Carbon dioxide ( chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is trans ...

() can be breathed off, resulting in an increase of plasma pH. The amount of respiratory compensation in metabolic acidosis can be estimated using Winters' formula. Hyperventilation due to the compensation for metabolic acidosis persists for 24 to 48 hours after correction of the acidosis, and can lead to respiratory alkalosis. This compensation process can occur within minutes. In

metabolic alkalosis Metabolic alkalosis is a metabolic condition in which the pH of tissue is elevated beyond the normal range (7.35–7.45). This is the result of decreased hydrogen ion concentration, leading to increased bicarbonate, or alternatively a direct res ...

sense a deranged acid-base balance with a plasma pH of greater than normal (>7.4). The chemoreceptors send afferent fibers to the brainstem respiratory centers. The brainstem respiratory centers decrease alveolar ventilation (

hypoventilation Hypoventilation (also known as respiratory depression) occurs when ventilation is inadequate (''hypo'' meaning "below") to perform needed respiratory gas exchange. By definition it causes an increased concentration of carbon dioxide (hypercapni ...

) to create a rise in arterial

() tension, resulting in a decrease of plasma pH. However, as there is limitation for decreasing respiration, respiratory compensation is less efficient at compensating for metabolic alkalosis than for acidosis. The respiratory brainstem centers can only compensate for metabolic acid-base disturbances (

and

Renal compensation Renal compensation is a mechanism by which the kidneys can regulate the plasma pH. It is slower than respiratory compensation, but has a greater ability to restore normal values. In respiratory acidosis, the kidney produces and excretes ammonium ...

is needed to balance respiratory acid-base syndromes (

respiratory acidosis Respiratory acidosis is a state in which decreased ventilation (hypoventilation) increases the concentration of carbon dioxide in the blood and decreases the blood's pH (a condition generally called acidosis). Carbon dioxide is produced continu ...

and

respiratory alkalosis Respiratory alkalosis is a medical condition in which increased respiration elevates the blood pH beyond the normal range (7.35–7.45) with a concurrent reduction in arterial levels of carbon dioxide. This condition is one of the four primary dis ...

). The kidneys can compensate for both, respiratory and metabolic acid-base imbalances.

References

{{Renal physiology Acid–base disturbances