Physiology of the developing kidney: Acid-base homeostasis and its disorders

Abstract

The body is highly dependent on acid–base control by the kidneys, lungs, and buffer systems to provide a cellular environment suitable for normal health, growth, and development. The acid and alkali loads from ingesting food and fluid must be managed so that the extracellular hydrogen ion (H+) concentration is maintained within a very narrow range. There are serious consequences from acid–base perturbations. Patients with severe acidemia, high blood levels of H+, may have problems with hyperkalemia, increased susceptibility to cardiac dysrhythmias, osteopenia, recurrent nephrolithiasis, skeletal muscle atrophy, and growth retardation in children. Conversely, patients with severe alkalemia, low blood H+ concentration, may experience arteriolar constriction, refractory dysrhythmias, hypoventilation, hypokalemia, decreased ionized calcium, paresthesias, and even coma. The following information will serve as practical assistance to physicians who manage acid–base problems in children.