Solutions such as blood can be neutral, acidic or basic. The acidity of a solution can be represented by pH. On the pH scale, 7 is neutral, numbers less than 7 represent acids, and numbers greater than 7 represent bases. The blood normally has a pH of 7.4. Certain disorders can make the blood acidic or basic. It is important to consult a physician for the diagnosis and management of health conditions.
Problems with pH Disoders
The body relies on proteins to carry out many functions in the body. Enzymes increase the rates of chemical reactions and ion channels allow electrical currents to flow. Acid and base imbalances change the environment in which these proteins are designed to function. This results in proteins not working efficiently and changes to the electrolyte concentrations in the body. Cells that rely most on electrical signaling such as the heart and nerves are particularly vulnerable.
Respiratory Acidosis
The lungs play a crucial role in acid-base balance. The breakdown of food for energy produces carbon dioxide which is taken to the lungs to be released from the blood into the air. Carbon dioxide combines with water in the body to make carbonic acid. So, higher carbon dioxide creates acid. Decreased respiration, as with certain drugs such as opiates, causes the carbon dioxide and acidity to rise. This is called respiratory acidosis.
Respiratory Alkalosis
Respiratory alkalosis occurs when a person is breathing out too much carbon dioxide through the lungs. As examples, it can occur with hyperventilation from anxiety or if a patient is on a ventilator that is set for too high a rate.
Metabolic Acidosis
Metabolic acidosis is the build up of acids from metabolic causes. These including conditions in which the kidneys are not removing acid or the body is making too much acid. Kidney failure leads to the build up of organic acids such as sulfates and phosphates that are mostly breakdown products of protein. Lactic acidosis can occur when tissues do not receive enough oxygen. Blood sugar is then broken down into lactic acid instead of carbon dioxide. Diarrhea can result in the loss of bicarbonate, which is a base.
Metabolic Alkalosis
Metabolic alkalosis occurs when the body loses acid or gains base. For example, vomiting causes the body to lose stomach acid and can lead to metabolic alkalosis. Some kidney conditions lead to acids being excreted. Another example is the excess ingestion of bicarbonate, as is found in many antacids.
References
- "Robbins and Cotran Pathologic Basis of Disease"; Vinay Kumar et al; 8th Ed 2009
- "Physiology"; Linda S.Costanzo; 4th Ed 2008
- "Current Medical Diagnosis and Treatment 2011"; Stephen McPhee, Maxine Papadakis, and Michael W. Rabow; 50th Ed 2010
