I 12 



Scientific Proceedings (33). 



index of the degree of circulatory disturbance produced, falls 

 abruptly to a lower level when the balloon is inflated. It then 

 remains fairly constant until a final collapse occurs just before 

 exitus. 



The liver and brain increase at once in volume as the result of 

 an acute passive dilatation caused mechanically by the increased 

 venous pressure. In the other organs and extremity a moderate 

 similar passive dilatation can be demonstrated if, but only if, they 

 have been put in a state of active contraction before the cardiac 

 obstruction is made. Thus when previously contracted directly, 

 by the intravenous injection of adrenalin, or reflexly, by sensory 

 irritation, their volume-curve rises during the period of cardiac 

 insufficiency. But unless thus previously contracted, the kidney, 

 spleen, intestine, and extremity decrease promptly in volume when 

 the heart is obstructed. This decrease overshadows the relatively 

 slight effects of the increased venous pressure, so that the presence 

 of the latter is only manifest in a short "additional fall" of the 

 volume-curve which occurs just at the moment when the obstruc- 

 tion is removed. This "additional fall" is synchronous with the 

 drop in the venous pressure, and occurs before the organs begin 

 to return to their normal size. 



The decrease in volume of these organs, on the other hand, 

 does not correspond to the fall of arterial blood-pressure, but may 

 continue for as much as five minutes after the latter has reached 

 its lowest point. It is due rather to an active contraction of the 

 arteries and capillaries tending to compensate for the blood lost 

 from the circulation by stagnation in the veins, liver, and brain. 



The foregoing work was conducted in the laboratory of the 

 Medical Clinic in Tubingen. I desire here to express my grati- 

 tude to Professor Romberg and his first assistant. Dr. Schlayer. 



