PUNCTURING THE BOWEL. 



575 



changes with production of gas still continue, even under considerable 

 pressure. 



Internal medicaments, supposed to neutralise or absorb intestinal 

 gases, act too slowly, and, like those given to prevent fermentation, 

 enter the colon too late to be of benefit. As the natural passage 



d ors al ^ i semispinalis 



// obi i go 

 abdom.int 



M.Panniculuscar., 



/f rectus abd 



ire n Ira I 



Fig. 408. — Vertical section of the horse" jbody between the last rib and 



external angle of the ilium. 

 i Femoral artery ; b, posterior vena cava ; c and c'. loops of small intestine ; 

 d, rectum ; e, colic artery ; /, inferior colic artery ; g, superior colic artery ; 

 h, arteries of the rectum ; i, ureter. (After Ellenberger and Baum.) 



for discharge of gas may be rilled with ingesta, the only method of 

 averting rupture or suffocation consists in providing an outlet for 

 the gas by trocar and cannula. 



The operation acts like puncture of the rumen ; but puncture 

 of the bowel in the horse is perhaps more dangerous, though recent 

 cases show that risk of peritonitis has been greatly overestimated. 



