Blood pH in Vivo

Various materials injected into the blood stream of living animals alter the acidity of blood, as has been proven by many experimenters. The usual method employed to follow the changes has been to analyze samples of blood drawn at selected intervals. It has been realized that while this is a valid procedure for changes that take place slowly, it is totally inadequate when rapid changes are involved. Since it is now possible to record directly the acidity of circulating blood in living animals, it is apparent that the problems involved in rapid changes of blood acidity should be further investigated by this new technic. This paper reports the effect on the acidity of arterial blood of the intravenous injection of certain acids, salts, and other substances.