Hydrogen ion Concentration and Carbon Dioxide Content of Blood of Parathyroidectomized Dogs.

Abstract

In recent years research in experimental and clinical tetany has led to the view that tetany occurs when the reaction of the blood shifts to the alkaline side. The fact that acid producing salts such as CaCl₂ and NH₄Cl causes the tetany symptoms to disappear, and the serum calcium to rise supports this view. Wilson, Stearns and Thurlow 1 report that the pH of the blood on the first day of tetany ranges from 7.6 to 7.75, and that the ingestion of 0.1 to 0.5 gm. of HCl brings relief. Grant 2 states that the symptomatic cure of infantile tetany by the use of NH₄Cl is strong evidence in favor of the view that there is an alkalosis in this condition. Freudenberg and György 3 maintain that tetany is the result of a decrease in ionized calcium, coincident with an increase in phosphate, brought about by a change in the reaction of the blood toward the alkaline side.

Drucker and Faber, 4 on the contrary, found that the pH values and the alkali reserve are no greater when tetany is manifest than when it is cured.

Hastings and Murray 5 determined the CO₂ combining power and CO₂ content in four parathyroidectomized dogs. They report only a slight drop. Measurements of the H ion concentration of the blood by means of a potentiometer were made on a different set of parathyroidectomized dogs. Their measurements were made at room temperature that varied considerably. After applying a temperature correction, calculated by Michaelis, they obtained a pH 7.45 for normal.

With this conflicting evidence it was decided to determine simultaneously the pH and CO₂ content of the plasma and calcium content of the serum.