Blood is normally slightly basic, with a pH range of 7.35 to 7.45. To function properly, the body maintains the pH of blood close to 7.40.The blood's acid-base balance is precisely controlled, because even a minor deviation from the normal range can severely affect many organs. The body uses different mechanisms to control the blood's acid-base balance.
Role of the Lungs: One mechanism the body uses to control blood pH involves the release of carbon dioxide from the lungs. Carbon dioxide, which is mildly acidic, is a waste product of the metabolism of oxygen.As with all waste products, carbon dioxide gets excreted into the blood.As carbon dioxide accumulates in the blood, the pH of the blood decreases (acidosis). The brain regulates the amount of carbon dioxide that is exhaled by controlling the speed and depth of breathing.
Role of the Kidneys: The kidneys are also able to affect blood pH by excreting excess acids or bases. The kidneys have some ability to alter the amount of acid or base that is excreted, but because the kidneys make these adjustments more slowly than the lungs do, this compensation generally takes several days.
Acidosis and Alkalosis are two abnormalities of acid-base balance.
Acidosis and alkalosis are categorized as metabolic or respiratory, depending on their primary cause. Metabolic acidosis and metabolic alkalosis are caused by an imbalance in the production of acids or bases and their excretion by the kidneys. Respiratory acidosis and respiratory alkalosis are caused primarily by changes in carbon dioxide exhalation due to lung or breathing disorders.