hormonal and metabolic disorders
Acidosis
Introduction
Acidosis is caused by an overproduction of acid that builds up in the blood or an excessive loss of bicarbonate from the blood (metabolic acidosis) or by a buildup of carbon dioxide in the blood that results from poor lung function or depressed breathing (respiratory acidosis). Blood acidity increases when people ingest substances that contain or produce acid or when the lungs do not expel enough carbon dioxide. People with metabolic acidosis often have nausea, vomiting, and fatigue and may breathe faster and deeper than normal. People with respiratory acidosis often have headache and confusion, and breathing may appear shallow, slow, or both. Tests on blood samples typically show pH below the normal range. Doctors treat the cause of the acidosis. (See also Overview of Acid-Base Balance .) If an increase in acid overwhelms the body's Control of Acid-Base Balance , the blood will become acidic. As blood pH drops (becomes more acidic), the parts of the brain that regulate breathing are stimulated to produce faster and deeper breathing (respiratory compensation). Breathing faster and deeper increases the amount of carbon dioxide exhaled, which raises the blood pH back toward normal. The kidneys also try to compensate by excreting more acid in the urine. However, both mechanisms can be overwhelmed if the body continues to produce too much acid, leading to severe acidosis and eventually heart problems and coma. The acidity or alkalinity of any solution, including blood, is indicated on the pH scale. 