LIGATION OF THE CAROTID ARTERY. 75 



siibscapulo-lij'oideus muscles and then force a passage with 

 the fingers, with the cautions aid of the- knife, to the trachea. 

 At the region of the neck indicated, the carotid passes along 

 the border between the lateral and dorsal surfaces of the 

 trachea, accompanied dorsally by the vagus and sympathetic 

 nerves and ventrally by the recurrent. In Figure 2, Plate XII 

 the vagus and sympathetic nerves, v and a, are pushed out 

 of their ilormal position and appear ventrally to the carotid. 

 Pass the index finger over and behind the carotid until the 

 trachea is reached, and encircling the inner and lower sides 

 of the artery, force a way through the surrounding areolar 

 tissue and draw the vessel out through the operation wound. 

 As a rule the carotid is still surrounded by the lamellar 

 fascia, which comes from the deep fascia of the neck iu 

 W'hich al.so the three above mentioned nerves are found. 

 These nerves must be carefully .separated from the carotid 

 and mu.st on no account be included in the ligature. Ligate 

 the carotid twice with an interval of about 2 cm. between 

 the two. ligatures and divide the artery midway between the 

 two. The second ligature is necessary in order to prevent 

 hemorrhage from the di.stal end through collateral anasto- 

 mo.ses and it is essential to sever the artery in order to avoid 

 its rupture by the stretching of tlje undivided carotid dur- 

 ing movements of the neck where the nutrition has been cut 

 off at the point of ligation. Provide drainage for the wound 

 and suture the mu,scle and skin. 



