The blood in “shock,”

Abstract

It has been stated that in conditions of “shock” concentration of the morphological elements of the blood may take place through outward passage of liquid from the blood vessels. 1

This point was investigated in a rather comprehensive experimental study of “shock” in etherized dogs. This condition was induced by rhythmical Faradic stimulation of the brachial plexuses and moderate hemorrhage. In general, death occurred within one or two hours. Small samples of the blood were withdrawn at regular intervals and defibrinated. The specific gravities and freezing points of the blood specimens were measured in eight experiments. The results are practically the same in all cases, and show that under the conditions of the experiments, physical alterations in the blood are not greater than may be accounted for by the loss of blood and certainly are not such as could affect the circulation sufficiently to account for the phenomena observed.

Relative to the total mass of blood, the amount withdrawn was, in round numbers, between 15 and 30 per cent., the average being 25 per cent.—–estimated on the total blood being 1/15 of the body weight.

The average arterial blood-pressure at the time the first blood sample was taken was 180.5; at the time of taking the last sample47 mm. Hg pressure. The average specific gravity of the first sample was 1.059; and of the last 1.056. The average change in freezing point was + 0.016.

Viscosity measurements were made in a few experiments. In this respect also there was insufficient evidence for attributing the clinical condition of the animal to mechanical change in the blood.