These buffers are the bicarbonate-carbonic acid buffering system, intracellular protein buffers, and phosphate buffers in the bone. Physiologic buffers, consisting of a weak acid (which can easily be broken down) and its base salt or of a weak base and its acid salt.The body has three compensatory mechanisms to handle changes in serum pH: The renal tubules, with the regulation of bicarbonate (HCO 3 -), excrete other acids produced from the metabolism of proteins, carbohydrates, and fats. The lungs release CO 2, an end product of carbonic acid (H 2CO 3). The lungs and kidneys are the main regulators of acid-base homeostasis. In order to maintain acid-base homeostasis, acid production must balance the neutralization or excretion. In addition, the body loses base in the stool. Under normal physiologic conditions, a person generates 50 to 100 mEq/day of acid from metabolism of carbohydrates, proteins, and fats. Acidemia and alkalemia refer to the process of acidosis or alkalosis, respectively, occurring in arterial blood.īody acids are formed as end products of cellular metabolism. At the other end, alkalosis results from a deficiency in H + ion concentration. Changes in H + ion concentration can be stabilized through several buffering systems: bicarbonate-carbonic acid, proteins, hemoglobin, and phosphates.Īcidosis, therefore, can be described as a physiologic condition caused by the body's inability to buffer excess H + ions. Because pH is measured in terms of hydrogen (H +) ion concentration, an increase in H + ion concentration decreases pH and vice versa.
Acidosis is a pH less than 7.35 alkalosis is a pH greater than 7.45. What's normal?Ī normal range for arterial pH is 7.35 to 7.45. Lastly, we'll discuss potential treatments for acid-base disturbances. In this article, we'll review normal acid-base physiology, acid-base disturbances, and lab techniques and mathematical calculations used to identify the cause of acid-base derangements. Accurately interpreting acid-base balance requires simultaneous measurements of arterial pH and plasma electrolytes, as well as knowledge of compensatory physiologic mechanisms. Many critical illnesses can upset a patient's acid-base balance, and a disturbance in acid-base equilibrium may indicate other underlying diseases or organ damage.