88 



SURGERY. 



can be protruded after its introduction into the bladder. These 

 claws are equally liable to catch the coats of the bladder as well as 

 the stone, and the operation has been superseded by the following. 



LITHOTRIPSY. 



This implies the crushing of the stone whilst in the bladder ; and 

 it is preferred to all other operations for disintegration. 



The cases most favourable for this operation are adults, where the 

 urethra is free from stricture, the bladder free from irritability and 

 not contracted, and the prostate not enlarged. A mulberry calculus 

 would be unfavourable for lithotripsy, on account of its hard cha- 

 racter. 



The instrument most frequently used is that of Heurteloup, or a 

 modification of it. It consists of two blades, which slide one upon 



Fig. 26. 



the other, the extremities being slightly bent. It can be introduced 

 into the bladder as a sound or catheter, and afterwards the blades 

 are separated, to grasp the stone. In the original instrument the 

 male blade was struck with a hammer, and thus the stone was broken ; 

 now the crushing power is that of a screw, variously adapted, — that 

 of Mr. Weiss being most simple and perfect. 



The extremities of the instrument have teeth, so as to retain the 



stone when grasped, and 

 Fig- 27. also fenestrae to allow of 



the escape of sand or pow- 

 dered stone. 



The patient must be 

 previously prepared for 

 the operation, by regula- 

 tion of the general health, 

 dilatation of the urethra, 

 and distension of the 

 bladder. The patient lies 

 on a convenient table or 

 bed, with the pelvis ele- 

 vated, so as to throw the 

 stone into the fundus of the bladder ; the bladder must be full, so as 

 to prevent its coats from being entangled in the instrument. If urine 

 cannot be retained, tepid water must be injected. The instrument 

 must be oiled and warm. 



