170 Surgical Diseases and Surgery of the Dog 



will be found to be much distended and often hypertrophic, but the 

 distension is not from gases, but from semi-fluid fecal matter. 



Unless a dog be abnormally fat, all forms of intestinal obstruc- 

 tion can, as a rule, be diagnosed as such by patient and persistent 

 external palpation of the abdomen between the fingers of both hands. 

 Foreign bodies may be felt in any part of the cavity, but generally 

 in the center. Most of them may be rendered visible with the 

 Roentgen rays. 



Treatment. This differs according as the obstruction is mobile 

 or fixed. Mobile obstructions are treated by therapeutic measures, 

 our object being to hasten their exit from the canal with the aid 

 of purgatives. But when their passage is arrested and they become 

 firmly lodged at any part of the canal, purgation is not only use- 

 less but decidedly harmful. In a few hours the wall at the site 

 of an obstruction is in a state of inflammation. The muscular 

 layers become edematous, and their activity is impeded, if not 

 altogether arrested. Should even slight inflammatory process have 

 started, any further peristalsis is at once checked, and cannot be 

 awakened by the action of drugs,' and if we remember that it is 

 only through the return of normal peristalsis that we can hope 

 for the natural removal of an obstruction the reasons for avoiding 

 purgation become self-evident. It may be laid down as a rule 

 that the administration of purgatives should be persisted in until 

 the advent of vomiting. As already stated, however, it is a mis- 

 take to wait for stercoraceous vomiting, which is evidence that the 

 obstruction has been of some duration, and that collapse is im- 

 minent. In Senn's experiments vomiting occurred about five days 

 after artificial obstruction had been established. 



At this stage a prompt and careful enterotomy offers the only 

 possible chance for recovery. With modern surgery no dog should 

 be allowed to die without an extreme attempt being made to render 

 the canal permeable. It is only after the inflammatory changes 

 at the seat of lesion have developed into gangrene that the per- 

 centage of recoveries is reduced to a minimum, but even then, life 

 may be saved by excision of the mortifying portion. Whether or 

 not resection of a portion of the bowel is necessary will depend 

 upon its viability. Congested bowel, even if dark red, may be 

 safely regarded as viable, .but a greenish tint indicates the pre- 

 sence of gangrene. All doubtful cases should be treated as septic. 



