[Skip to Content]
[Skip to Content Landing]
November 21, 1977

Metabolic Alkalosis

JAMA. 1977;238(21):2288-2290. doi:10.1001/jama.1977.03280220056022

METABOLIC ALKALOSIS, a primary increase in the alkali content of the blood, is commonly seen in hospital practice. Increase in blood pH reduces ionized calcium concentration and can lead to tetany. The irritability of the CNS increases and convulsive tendencies are aggravated. Respiration can be depressed. Electrocardiographic changes resemble those of hypokalemia. Especially in patients receiving digitalis, or when there already exists serious systemic disease, alkalosis may be a potentially serious hazard.1

DEFINITION OF METABOLIC ALKALOSIS  As the Pco2 of blood rises above the normal value of 40 mm Hg, blood pH falls (so-called respiratory acidosis). Progressive reduction of Pco2, below normal, leads to elevated blood pH (respiratory alkalosis). The actual confidence band relating pH to Pco2 of arterial blood has been experimentally determined.2 Metabolic alkalosis is defined by a blood pH above that predicted for the prevailing Pco2, for only removal of excessive