I02 PUNCTURE OF THE INTESTINES. 



flank about equi-distant from the last rib, the extremities 

 of the transverse processes of the lumbar vertebrae and the 

 external angle of the ilium in the standing horse ; at the 

 uppermost point of the abdomen in the recumbent animal, 

 that is, at the most prominent part of the distension. After 

 the skin at this place has been clipped or shaved and disin- 

 fected gasp the trocar with the index finger and the thumb 

 of the left hand and holding the instrument perpendicular 

 to the body surface, give it a firm, quick blow with the 

 palm of the right hand and drive it through the abdominal 

 wall into the intestine. 



With a properly constructed trocar of the dimensions 

 suggested in Figure 8 no preliminary puncture with the 

 lancet is required or advisable. The cutting end of the 

 stilette should be very long, tapering and sharp so that it 

 will cut as freely as a lancet. By performing the opera- 

 tion as directed the trocar ordinarily punctures the caecum. 



Fig. 8. 



Intestine trocar with sheath. Outside diameter of canida 3 mm., 

 length of canula, 16 cm. 



Withdraw the stilette and permit the gas to escape 

 through the canula. The canula may become occluded by 

 particles of ingesta entering it and these should be removed 

 by reinserting the stilette. The intestine first punctured 

 may collapse and the flow of gas cease while the tympany 

 continues in other parts ; this may be overcome by reintro- 

 ducing the stilette and pushing the trocar through the 

 distal wall of the bowel and into the intestine beyond. If 

 this does not succeed, the trocar may be withdrawn and 

 reinserted in a neighboring area or if need be on the 

 opposite side of the animal. 



