Acid-base Paths in Human Subjects.

Using the micro-acid-base technique 1 a study has been made of the acid-base variation under experimental conditions of 6 patients (2 cases of nephrosis, 2 of diabetes, and 2 of nutritional edema). The normal acid-base balance was displaced toward the acid side by the administration of ammonium chloride or hydrochloric acid, and toward the alkaline side by the administration of sodium bicarbonate. Frequent determinations of the acid-base balance were made during the course of the displacement from and the return to normal. Approximately 7 determinations were made during the 8 hours following the administration of the salts, and several determinations were made on the succeeding days.

The results when plotted on a triaxial coordinate chart may be described as follows: After a change is produced in the serum bicarbonate by fixed acids or alkalies the path taken by the blood is toward a changed pH and CO₂ tension. The change in pH is approximately 2 times the corresponding change in CO₂ tension when the latter is expressed logarithmically. The direction may be stated as being approximately at right angles to the direction taken by the CO₂ absorption curve of blood plotted on the triaxial coordinate chart.