AND BLOOD PRESSURE 



179 



so that the cerebral, coronary, and pulmonary vessels are well 

 filled. 



Direct transfusion of human blood from artery to vein has been 

 used by Crile in extreme cases of simple shock. It is unwise to 

 use this in any state of toxaemia, for hsemalysins may then 

 come into play. Injection of physiological saline is found a 

 valuable aid. 



In collapse brought about by the injection of bacterial toxins, 

 it is said, the synapses of the vaso-motor centre are at fault, so 

 that neither excitation of a sensory nerve nor asphyxia provoke 

 any rise of arterial pressure, while compression of the abdomen or 

 of the descending aorta provokes it, showing that the heart is not 

 exhausted and can still respond with increase of energy to better 

 filling, and increased resistance to its output (Romberg). 



Babbit : 0'2 gm. Chloral introrvenuusly injected. 



These figures show the relative effect of paralysis of vaso-motor 

 nerves and of damaging the heart by chloral, and with them the 

 following may be contrasted : 



