66 INTRAVENOUS INJECTION 



Technic. Operate on. the standing animal. Perform 

 tracheotomy (page 63). Elevate the gravity apparatus 

 containing the irrigating fluid i to 2 m. above the patient, 

 have the animal's head slightly elevated, insert the free end 

 of the rubber hose in the trachea tube and let the fluid flow 

 into the trachea in a moderate stream until the animal makes 

 expulsive efforts, when the inflow is stopped and the animal 

 permitted to lower his Ije^d and expel the fluid, then raise 

 the head again and repeat until the fluid is expelled clear. 

 Repeat the operation according to requirement. 



16. INTRAVENOUS INJECTION 

 Fig. 24 



Instruments. Scissors, hypodermic .syringe. 



Technic. The operation is performed on the standing 

 animal on either jugular vein at about the juncture of the 

 upper and middle thirds of the neck ; to most operators the 

 right jugular is the more convenient. At the place desig- 

 nated, the subscapulo-hyoideus muscle lies between the 

 jugular vein and the carotid artery and affords some pro- 

 tection against injury of the latter. After clipping the hair 

 and shaving, the skin should be carefully disinfected pre- 

 ferably with tincture of iodine. The vein lies in the jugular 

 groove between the mastoido-humeralis and the sterno- 

 maxillaris muscles, covered only by the skin and skin muscle. 



Stand by the shoulder of the horse and compress the 

 jugular with the thumb as shown in Fig. 24 or with the 

 second to the fourth fingers, in which case the ball of the 

 thumb rests on the mastoido-humeralis muscle. The vein 

 becomes filled above the point of compression in the shaved 

 area and stands out as a swollen cord. In fleshy-necked 

 horses eflScient compression is more readily attained if the 

 head is somewhat elevated and extended by an assistant. 

 If the vein cannot be made prominent in this way, the 



