Abstract

1. Avertin fluid, avertin crystals, and amylene hydrate, in concentrations much higher than are found in normal avertin anesthesia in man, produce no deleterious effects upon the heart.

2. In much greater concentrations these drugs slow the heart, diminish the peripheral putput and increase the coronary circulation.

3. Adrenaline in avertin anesthesia frequently produces cardiac irregularity and in heart-lung preparations occasionally causes ventricular fibrillation.

4. Experiments using a mechanical heart indicate that the peripheral circulation as well as the heart is affected by avertin. The importance of this action is rather difficult to evaluate, but it appears to be of comparatively little importance.