384 



OPERATIONS ON THE DIGESTIVE APPARATUS. 



the effusion, has been successfully added as a means of preventing- 

 the return of the fluid. 



In selecting the place where the operation is to be performed, 

 Brogniez, Degives, Peuch and Toussaint ad\ised the middle of 

 the hnea alba, at an equal distance from the xiphoid cartilage of 

 the sternum and the anterior border of the pubis ; Zundel, on the 

 contrary, recommends " a puncture on the right side in ruminants, 

 on the left in horses, on a point at an equal distance between the 

 umbilicus and the external angle of the ilium, about on a line run- 

 ning from the stifle towards the cartilage of the last rib." He 

 adds, however, "to select the point where the liquid is most de- 

 tectable and fluctuation better felt." 



A trocar of the size of a quiU for large animals, and an aspirator 

 for the smaU, are the only instruments required. In operating on 

 large animals, they are kept standing, while small animals are laid 

 upon a table and placed slightly on their backs. Placing himself 

 on the left side of the animal, after having selected the place 

 where the puncture is to be made, the operator, holding the trocar 



Fig. 371.— Holding the Trocar in Paracenthesis. 



full in his hand and limiting its action by keeping his fingers a 

 short distance from the point of the instrument, jjushes it by a 

 rapid and firm pressure through the thickness of the abdominal 

 waUs, until he feels that he has overcome their resistance, and that 

 the instrument has passed into the cavity. The trocar is then 

 withdrawn from its canula and the fluid escapes through the tube. 

 Director Degives describes another modus operandi, which he 

 calls subcutaneous, in which the opening of the skin does not cor- 

 respond with the division of the deeper muscular layers, and by 

 which the opening becomes covered by the skin. To effect this 

 the skin is drawn a little aside, then punctured, or a large fold of 

 the tegument is taken hold of, and the puncture made at its base. 

 In either case, when the skin is loosened, its retraction comjjletely 

 closes the abdominal opening. 



