MEASUREMENT OF VOLUME OF DOG'S HEART BY X-RAY: EFFECT OF HEMORRHAGE, OF EPINEPHRINE INFUSION, AND OF BUFFER NER VE SECTION

Abstract

A nomographic chart of the relation of heart shadow area to the cardiac volume in dogs is presented. The size of the heart is reduced in hemorrhage by a figure that may amount to 1/4 of the lethal bleeding volume. It is increased by epinephrine but is not enlarged by an equal hypertension produced by buffer nerve section. These changes are in the same direction as those previously seen in the intrathoracic blood volume as calculated from the dye-injn. method and are of such magnitude as to account for a great part of these latter changes.