(hi (i'it*hot Injuries of the Cerebral Hemispheres. [Mar. 15, 



VII. " On the Effects produced on the Circulation and Respira- 

 tion by Gunshot Injuries of the Cerebral Hemispheres." I>y 

 S. P. KRAMER, M.D., and VICTOR HORSLEY, M.B., F.R.C.S., 

 F.R.S., Professor of Pathology in University College, 

 London. Received February 21, 1894. 



(From the Laboratory of the Pathological Department, University College, 



London.) 



(Abstract.) 



In consequence of the fact that the effects produced on the circula- 

 tion and respiration by a bullet passing through the cerebral hemi- 

 spheres are but little understood, the authors instituted a series of 

 pathological experiments on etherised dogs, and of physical experi- 

 ments on various substances. 



The results obtained establish, beyond question, that the primary 

 cause of death under these circumstances is not, as is usually sup- 

 posed, due to failure of the heart, but to arrest of the respiratory 

 movements. Further, the authors have found, in confirmation of this, 

 that death can be prevented by the employment of artificial respira- 

 tion, except under certain circumstances detailed in the paper. 



After describing the changes in the circulation produced, and which 

 consist of (a) slight initial fall of blood pressure, (6) considerable 

 later rise of blood pressure, (c) preservation of the rhythm of tl 

 heart, the authoi-s discuss the physical effects of the projectile on tb< 

 encephalic contents, and they show, as was originally contended bj 

 Professor Kocher, that the action of the bullet is essentially a 

 hydrodynamic one, and that it is the lateral pressures which cause 

 UK chanieal lesion of the respiratory centre. 



In this respect the results obtained further support the original 

 observations of Spencer and Horsley, recently confirmed by Hill, viz. 

 that the respiratory centre is the first to be seriously affected by 

 changes in the infra-cranial tension. 



Finally the authors point out that, supervening on the primary 

 arrest of respiration, there ensues a gradual rise in the intra-cranial 

 tension due to the haemorrhage within the skull cavity, and that the 

 phenomena which then follow are the same as those described in the 

 above-mentioned paper. 



