154 DISEASES OF THE (ESOPHAGUS. 



Treatment is confined to one essential point — removal of the 

 obstruction. The chief difficulty lies in choosing the mode of inter- 

 vention, iloreover, success depends on several factors, which, in the 

 order of their imijortance, are as follows : the size of the obstructing 

 body ; the time ^Yhich has elapsed since the accident occurred ; the 

 bodily condition of the animal — i.f., \Yhether it be fat or thin — and the 

 extent to which tympanites has developed. 



The first thing to do (and in favourable cases all that is required) is 

 to puncture the rumen and leave the canula for some time in position. 

 The onward progress of the foreign body, especially when the obstruc- 

 tion is in the intra-thoracic portion of the tube, is often impeded by the 

 tympanites, which tends to thrust the object towards the pharynx, or at 

 least to fix it in position. In consequence of a sudden change in the 

 conditions of pressure the foreign body may move and pass into the 

 rumen ; all danger is then at an end. 



Even though the obstruction does not immediately cease, puncture of 

 the rumen, by removing the danger of asphyxia, allows one at least to 

 wait for several hours, sometimes until next day, during which time the 

 object may pass into the rumen without further extraneous assistance. 

 The other methods may be grouped into four series : 



I. External taxis. This is directed towards loosening the foreign 

 body and thrusting it towards the pharynx and buccal cavity. It can 

 only be used against obstructions in the cervical region. Two methods, 

 although very ancient, are still practised. 



(a) The first is carried out in the following way : the animal is fixed 

 to a post or tree so that it cannot struggle, its head being drawn up as 

 high as possible. The operator stands on the left side, with his back 

 turned towards the patient's head, his left hand is pressed into the right 

 jugular furrow, his right hand is placed on the left jugular furrow imme- 

 diately below the foreign body. By using the fingers the foreign body 

 is moved, and is progressively thrust towards the pharynx, in spite of the 

 animal's efforts to swallow. In carrying out this manipulation it is 

 absolutely indispensable not to let slip the obstructing body for a single 

 instant, otherwise the peristaltic action will immediately return it to its 

 former place. When it has been raised as far as the pharynx, an 

 assistant passes his hand into the back of the mouth, as indicated in a 

 former chapter, seizes the object and withdraws it ; or, instead, the 

 assistant takes o\'er the operator's duties, while the latter himself 

 extracts the foreign body. 



(h) In the second method the animal is fixed in a different position, 

 the head being held about 10 to 12 inches from the ground, with the 

 neck lowered and inclined towards the earth. As in this position the 

 lesophagus is longitudinally relaxed, and can be dilated to its fullest 



