On the influence of CO 2 on the viscosity of the blood

Abstract

It has been proved by the author¹ that the blood in the veins possesses a somewhat greater viscosity than the blood in the arteries. As this difference is caused no doubt by the greater amount of CO₂ present in the venous blood, it became of some consequence to determine whether the arterial blood could be made to assume a greater viscosity by increasing its CO₂ content.

The dogs used in these experiments received alternately a supply of normal air and air charged with CO₂. During the period of inhalation of the air plus CO₂ the arterial blood showed a somewhat greater viscosity than during the time when the animal breathed normal air. The changes appeared very promptly, but were never very conspicuous. The specific gravity of the blood pursued a course parallel to that of the viscosity.