Acidosis occurs when the pH of the body becomes disrupted, resulting in an excess of acid. Body pH is normally maintained by the lungs and kidneys, so when these organs become compromised, acidosis of the body fluids occurs. There are two main kinds of acidosis: respiratory and metabolic. Both of these forms produce similar symptoms of acidosis, including generalized symptoms and more specific respiratory, cardiovascular, and physical sensations.
Respiratory acidosis occurs when the lungs become unable to efficiently remove enough carbon dioxide from the body. This can be caused by diseases such as sarcoidosis, medications, and obesity. Metabolic acidosis occurs when the kidneys become compromised and cannot sufficiently remove acid from the body or when the body produces an excess that overloads the kidneys. Diabetes, hyperchloremia, and liver failure can all contribute. Both respiratory and metabolic acidosis can be acute or chronic.
Confusion, fatigue, and lethargy can all be symptoms of acidosis. Symptoms of this type can be quite general and can often be attributed to other conditions. These symptoms occur in acidosis due to the depression of the central nervous system and, without treatment, can progress until the person becomes unconscious or even comatose. Headache is another symptom, which is caused by the dilation of the blood vessels in the brain.
Respiratory symptoms of acidosis differ between the two types. In respiratory acidosis, shortness of breath can occur due to the paralysis of the respiratory muscles. With metabolic acidosis, the person exhibits deep, rapid breathing. Called Kussmaul respiration, this is caused by the body attempting to compensate for the excess of carbon dioxide by increasing the rate it is expelled from the body, thus decreasing acidity.
There are also cardiovascular symptoms of acidosis. These symptoms are the same for both types and include an increase in heart rate. This increase is due to the stimulation of the sympathetic nervous system by the high acid levels, which subsequently releases catecholamines, epinephrine, and norepinephrine.
Finally, there are physical sensations that are considered characteristic symptoms of acidosis in both types. The dilation of the blood vessels, besides causing headaches, also causes a warm, flushing sensation in the skin, especially of the face and chest. A tingling sensation can also develop in the fingers and toes, which may spread to the entire hand or foot. This symptom is caused by the drop in serum calcium levels as a result of the increased acidity in the body fluids, resulting in hypocalcemia. If left untreated, this can develop into full-blown convulsions and muscle hypotonia.