Acid-base balance - Overview: Nursing

Acid-base balance refers to how the body maintains a balanced pH of body fluids within a narrow range. A balanced pH is essential for optimal cellular functioning; and any disruption in this balance can adversely affect important metabolic processes, such as the function of enzymes within cells, oxygen delivery to the tissues, and medication metabolism.

Alright, so, pH, which means potential of hydrogen, reflects the concentration of hydrogen ions, or H+, in the blood. An acid is a substance that releases H+, and there’s an inverse relationship between pH and H+, meaning that when there’s more H+, the pH decreases and the blood becomes more acidic; and, when there’s less H+, the pH increases, and the blood becomes less acidic. Now, hydrogen ions are continually produced by normal metabolic processes like ketone production from fat metabolism; phosphoric acid from the breakdown of proteins; and lactic acid resulting from aerobic respiration, which can be due to excess exercise or hypoxia.  

On the flip side, a base is a substance that accepts hydrogen ions, which neutralizes acid. Bicarbonate or HCO3-, is a base found in plasma, and it plays a crucial role in acid-base balance. When there’s more HCO3- the pH increases, and the solution becomes more basic; and when there’s less HCO3-, the pH decreases, and the solution becomes less basic.   

Okay, so pH is measured on a scale that ranges from 0 to 14, with a pH of 7 being neutral, less than 7 being acidic, and more than 7 being more alkaline. Optimal metabolic functioning occurs when the pH is maintained between a range of 7.35 and 7.45.