26 



Dr. J. Rose Bradford. 



[Mar. 3, 



thus obtained. In the earlier experiments only the quantities of 

 urine and urea passed were determined. On removal from the 

 chamber, the animal is again weighed. 



Secondly. — The operation described below is performed on one 

 kidney. After recovery from this, the dog is again placed in the col- 

 lecting chamber, and the above data again obtained for a week or more. 



Thirdly. — The second kidney is removed, and the animal again 

 placed in the collecting chamber, the food and excreta being again 

 determined for a period of a week or more. 



Fourthly. — At a variable time after the second operation the animal 

 is killed by bleeding, and the amount of nitrogenous extractives 

 present in the tissues determined. 



As regards the operative procedures, there is nothing to remark 

 about the second operation — the kidney is removed in the usual 

 manner by lumbar incision ; a few words are necessary in order to 

 describe the first operation. After anaesthetising the animal with 

 chloroform and morphia, the kidney is exposed by a lumbar incision 

 and freed from its connexions. The vessels in the hilus are then com- 

 pressed with the fingers, the kidney transfixed from before back, and 

 a large wedge of kidney substance, with the apex of the wedge at 

 the pelvis of the kidney, removed from the middle of the organ. The 

 piece removed weighed from 5 to 15 grams in different cases. The 

 very free haemorrhage is arrested by ligature of the large vessels 

 divided, and by pressure on the cut surface. When all bleeding had 

 been arrested (the vessels in the hilus being of course no longer com- 

 pressed) the cut surfaces of the kidney were brought together by two 

 or three silk sutures passed in deeply, and by numerous superficial 

 tine horsehair sutures involving only the cortex and capsule of the 

 organ. The abdominal wound was closed and dressed in the usual 

 manner. 



Full antiseptic precautions were always used, and morphia was 

 given hypodermically to prolong the narcosis. 



Summary of Experiments. — Twenty-three animals survived the first 

 operation : fifteen animals survived both operations. 



Thus, eight animals died after the first operation and before the 

 second. The causes of death in these eight were as follows : — 



In four cases the animals were accidentally killed with chloroform 

 administered to perform the second operation. In two cases the 

 wound became septic and the animals were killed. In one case death 

 resulted from haemorrhage on the seventh day, and one dog, to which 

 f urth er reference will be made below, died of asthenia thirty-six days 

 after the first operation. 



This communication deals with the results obtained in the fifteen 

 complete experiments. In one, the first, no observations were made 

 on the urine, and in three dogs the observations were incomplete, so 



