382 OPERATIONS ON THE DIGESTIVE APPARATUS. 



was formerly employed, but it is quite unnecessary and of no ad- 

 vantage to use a canula of such dimensions merely to allow the 

 escape of the gases. A small, round trocar is now in general use, 

 and is in our estimation to be preferred to the ordinary flattened 

 form of instrument (Fig. 369). The enterotome of Brogniez (Fig. 

 370) is too large an instrument, and its use endangers the walls 

 of the intestines and the siuTounding blood vessels. 



Brogniez reports a case of injury to one of the coecal arteries 

 by the point of this instrument. We have frequently had re- 

 course to the trocar of the epidermic syringe used for horses, 

 when no other instrument was conveniently at hand. 



The animal suffering with flatulent colics is treated while on 

 its feet, and the pain it endures is usually of so intense a kind 

 that no means of restraint are necessary, and it remains per- 

 fectly indifferent to the insignificant and minor pang of the oper- 

 ation. The principal caution to be observed, is to be on guard 

 against the patient's suddenly falling, but if this should occiu- it 

 need not interrupt the operation, which may be continued with- 

 out forcing it to rise. 



The modus oj^erandi is very simple. The spot being acurately 

 determined, the point of the instrument is pressed perpendicu- 

 larly upon the skin with one hand, and di'iven by a strong, quick 

 blow with the other upon the handle, through the skin and the in- 

 testinal coats into the visceral cavity. The withdrawal of the rod, 

 leaving the canula in place, completes the process, by giving vent 

 to the gases. These escape with more or less force, as announced 

 by a whistling sound as they pass out of the tube. The intestines 

 must then be entered from above downward, and not as recom- 

 mended by Hertwig, who punctures the most dependent part of 

 the abdomen, and thus exposes his patient to serious subcutaneous 

 infiltrations. 



Peuch and Toussaint suggest the propriety of making a 

 small preparatory incision through the skin with a bistoury, pre- 

 vious to the main punctui'e with the trocar. The escape of the 

 gases continues for a varying time, according to the amoimt of 

 the accumulation. The instrument should continue in the 

 wound while the escape continues, and until the tympanitic con- 

 dition of the intestines disappears. If the escape of gas should 

 suddenly cease, it will be because the canula is filled with fcecal 

 or other matters, and the trocar must be re-inserted into its 



