ANEURISM OF THE AORTA. 423 



externally, the integument gradually grows thinner, turns dark blue, 

 then black, and at last sloughs. After a time, the eschar separates. 

 The blood, nowever, does not always escape in a stream. Sometimes 

 it is restrained by the coagula, so that there is only a gradual trickling 

 flow ; and it may even be possible to stanch the first haemorrhages 

 by means of the tampon, so that death may not occur until after re- 

 peated outbursts of blood. 



It is otherwise when rupture takes place into the pleura, pericar- 

 dium, trachea, or oesophagus. The patient then sinks, often with ex- 

 treme rapidity and in the midst of great suffering, with the signs of an 

 internal haemorrhage or of profuse haemoptysis or haematemesis. 



Life has been known to continue for some time after perforation of 

 the pulmonary artery, or vena cava. The symptoms observed were 

 those of extreme obstruction of the veins of the aortic circulatory 

 system. 



Although the most important symptoms of aortic aneurism are de- 

 rived from physical exploration, yet dyspnoea, cyanosis, varicosity of 

 the veins, and dropsy of the upper half of the body, severe pain in the 

 right side and arm, inequality of pulse at the wrists, the long pause 

 between the beat of the heart and that of the pulse at the wrist, permit 

 us to infer the existence of this disease with great certainty. The signs 

 vary, of course, according to the position of the tumor upon the aorta. 



In aneurism of the ascending a orta, the vena cava and lungs are 

 more especially encroached upon, so that cyanosis and dropsy of the 

 upper half of the body, with intense dyspnoea, form the most constant 

 symptoms. 



In aneurism of the arch, it is mainly the trachea and the par vagum 

 nerve which are compressed, and corresponding functional disturbance 

 ensues. In many cases, also, there is dysphagia, from pressure upon 

 the oesophagus. Inequality in the pulses at the wrists, also, is most 

 frequent in these cases. 



In aneurism of the descending thoracic aorta there is often severe 

 pain in the back, sometimes inability to extend the spinal column, and, 

 if destruction of the vertebrae be extensive, there may be paraplegia. 

 There are also sometimes difficulty in deglutition and severe dyspnoea 

 from compression of the lungs. 



The functional derangements and subjective symptoms, to which 

 aneurism of the abdominal aorta gives rise, are manifold. It may 

 cause the most violent neuralgic pain, and, at a later period, palsy of 

 the lower extremities, by pressure upon the nerves and erosion of the 

 vertebrae. Compression of the digestive apparatus occasions colic, con- 

 stipation, and vomiting. Pressure upon the liver and its excretory 

 ducts may produce obstinate jaundice ; while suppression of urine 



