68 PHLEBOTOMY 



Just above the point of compression, the vein is the most 

 fully distended and firmly fixed. After testing the hypo- 

 dermic needle to see that it is open, hold it between the 

 first and second fingers while the thumb covers its basal 

 opening and thrust it through the skin, cutaneous muscle 

 and jugular wall, in the direction of the vein obliquely for- 

 ward and upward 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 be partly withdrawn and then pushed in again in a slightly 

 different direction. 



Be careful that the hypodermic syringe contains no air. The 



material to be injected should be warmed to approximately the 

 body temperature. The syringe is then connected with the 

 needle 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 precau- 

 tion frequently results in the formation of a subcutaneous 

 hematome. 



17. PHLEBOTOMY 

 Fig. 24 



Instruments. Razor or scissors, lancet, phlebotomy tro- 

 car, pins, suture material. 



Technic. Phlebotomy may be performed on either jugular 

 vein. , The operation is preferably carried out on the 

 standing animal, but is not difficult when the patient is re- 

 cumbent. The point of operation is at about the boundary 

 line between the upper and middle cervical regions, be- 

 cause it is here that the subscapulo-hyoideus muscle, which 

 separates the jugular vein from the carotid artery, is most 

 voluminous and consequently affords the greatest protec- 



