Abdominal Vessels and Regions. 263 



nent place. This pain may shoot to the epigastric or to 

 the umbilical regions, in which case, it is due to the con- 

 nection of the solar plexus with the intercostal nerves, or 

 it may dart towards the pu'bes or into the thigh as far 

 down as the knee. When the pain is found in the latter 

 situations it may result from the direct pressure of the sac 

 on the upper lumbar nerves, i.e., on the ilio-hypogastric, 

 ilio-inguinal, etc., or it may be reflex in character, the irri- 

 tation being conveyed from the stretched aortic plexus of 

 the sympathetic to these lumbar nerves. Movement, such 

 as sneezing, coughing, straining, etc., intensify the pain, 

 since the blood pressure* is increased by these actions. 

 Should the aneurism erode the vertebral column there is 

 added a gnawing, boring pain. Pressure on the stomach 

 or bowels, or on the nerve plexuses supplying them, pro- 

 duces symptoms of a dyspeptic character, while pressure 

 on the renal vessels may cause ursemia ; on the vena cava, 

 cedema of the lower limbs ; or on the bile duct, jaundice. 

 Direct pressure by the surgeon on the aneurism will cause 

 increased tension in the femorals, and, if the pressure be 

 suddenly removed, there will result a temporary cessation 

 of the femoral pulsation because of the aspirating in- 

 fluence of the suddenly distended aneurismal sac. If both 

 femorals be compressed there is an increase of tension in 

 the tumor. These manipulations, however, are dangerous, 

 since rupture may result from the sudden strain that is thus 

 put upon the sac. When examining a patient for suspected 

 abdominal aneurism it is advisable to have him change 

 his position from back to side, or to assume the genu- 

 pectoral position. The object of this change of posture is 

 to assist in diagnosing a tumor involving the intestines, 

 the mesentery or the omentum, from an aneurism. The 

 tumor might receive pulsations from the underlying aorta, 

 but, when the patient is made to change his position, it 



