298 



The Abdomen 



remnant of the gateway of the placental vessels. As the aorta bifurcates 

 at the left of \hzfourth vertebra, the origin of the two common iliac 

 arteries is represented by a spot about one and a-half inches below 

 and slightly to the left of the umbilicus ; thence to the middle of 

 Poupart's ligament the line of the common and external iliac arteries 

 can be chalked upon the surface ; the first two inches of the line belong 

 to the common, the rest to the external iliac artery. 



In compression of the aorta the viscera should be empty and the 

 trunk flexed, so as to slacken the abdominal wall ; pressure is made 

 immediately below and to the left of the umbilicus. Higher than this 

 compression is less serviceable, as the ribs hold off the abdominal wall 

 from the spine. Moreover, at the higher level important viscera lie 

 in front of the aorta, and these might be damaged by the force 

 needed to arrest the circulation. 



Umbilical hernia. In early development the abdomen is wide 

 open in front, the lateral walls coming forward subsequently to join 

 along the median line. The part last closed in is at the umbilicus, 

 and this gap may persist after birth, the viscera being there covered 

 only by integument and peritoneum. A piece of bowel escaping by 

 the side of the hypogastric arteries may be accidentally tied or cut 

 with the navel-string. A bulky cord should, therefore, be carefully 

 dealt with, lest a loop of intestine be wounded and a faecal fistula 

 result ; it should be first emptied of bowel and then tied close to the 

 abdominal wall. 



//.A. 



H.K, 



Diagram of back of um- 

 bilicus, showing linea 

 alba, remains of urachus, 

 u; obliterated hypogast. 

 arts., H A, and umb. 



Embryo at loth week ; /, coil of intestine in umb. 

 cord ; Z', umb. vesicle. (A. THOMSON.) 



vein, u v. 



Umbilical hernia in childhood is merely the result of an arrested 

 development. In the adult the protrusion is not exactly at the navel- 



