68 INTRA VENOUS INJECTION. 



shorn area and stands out as a swollen cord. In the case of 

 fleshy necked horses this compression is more readily attained 

 if the head is somewhat elevated and extended by an 

 assistant. If the vein can not be made prominent in this 

 way the compression should be alternately applied and with- 

 drawn suddenly, the course of the vein then reveals itself by 

 a wave-like movement along the jugular groove. Just above 

 the point of compression the vein is the most fully distended 

 and firmly fixed. After testing the hypodermic needle to 

 see that it is open hold it between the second and third 

 fingers while the thumb covers its posterior opening and 

 thrust it through the skin, cutaneous mu-scle and jugular 

 wall, in the direction of the vein obliquely forwards and up- 

 wards I to 2 cm. deep, so that the point of the needle enters 

 the vessel at its most distended part. In this way it is easy 

 to prevent injury to the median wall of the vein. If the 

 vein has been properly punctured blood will flow from the 

 needle upon the removal of the thumb. If the vein is not 

 entered at the first attempt the needle .should be partly with- 

 drawn and then pushed in again in a slightly different direc- 

 tion. The compression is then removed and the hypodermic 

 syringe in which no air is contained is connected and the 

 contents slowly discharged into the vein. In withdrawing 

 the needle be careful to press the skin firmly against the 

 underlying part. The omission of this precaution frequently 

 results in the formation of a subcutaneous hematome. 



