Physicians often use an arterial blood gas (ABG) test and a basic metabolic profile blood test to make an acidosis diagnosis. The lungs and the kidneys are the major acid/base buffers in the body and these tests generally indicate which system is affected. Further testing generally reveals whether medical conditions or toxicity are contributing factors. Diabetes, cancer, heart, kidney, and liver disease, along with lung disease can cause acidosis. Treatment may include oxygen supplementation or infusions of sodium bicarbonate to reduce acid levels in the blood.
When acid levels in body fluids rise above normal levels, the condition is known as acidosis, which can be caused by elevated levels of carbon dioxide. The lungs and the kidneys take turns maintaining the balance of acids and bases in the body. When the lungs cannot acquire enough oxygen, carbon dioxide levels in the blood increase, causing respiratory acidosis. When this occurs, the kidneys attempt to compensate by allowing an increase of sodium bicarbonate in the bloodstream.
Metabolic acidosis occurs when the kidneys cannot filter enough acids from the blood. The lungs respond by taking in more oxygen in order to neutralize the acid. Diabetic acidosis, also called ketoacidosis, is the result of the presence of ketones in the bloodstream that have developed because the body cannot regulate blood sugar levels. Lactic acidosis might occur after an intense period of physical exercise or because of heart, kidney, or liver disease.
Health care providers commonly use ABG as a means of acidosis diagnosis. The test indicates the partial pressure of oxygen and carbon dioxide and the pH of the blood. It also reveals the levels of oxygen and sodium bicarbonate. If the ABG indicates a blood pH of below 7.35, acidosis is diagnosed. A drop in the carbon dioxide or sodium bicarbonate levels indicates whether the acidosis is respiratory or metabolic.
Health care providers often order a basic metabolic profile, or chem-7, blood test, to obtain information about electrolyte imbalances that may contribute to acidosis. A laboratory technician generally performs the test after drawing blood from a vein. The test provides information about glucose, calcium, sodium, and potassium levels. Basic metabolic profiles also reveal the levels of chloride, carbon dioxide, or sodium bicarbonate, blood urea nitrogen (BUN) and creatinine in the blood.
Tests revealing hyperchloremia, or higher than normal chloride levels, may provide a basis for a metabolic acidosis diagnosis. Hypochloremia, or decreased chloride levels, generally suggests that a respiratory acidosis diagnosis is appropriate. Abnormally high carbon dioxide levels typically indicate respiratory acidosis while lower than normal levels suggest ketoacidosis or metabolic acidosis. Hyperkalemia, or elevated potassium levels, might indicate either metabolic or respiratory acidosis.