164: DISEASES OF THE PARENCHYMA OF THE LUNG 



stand why the disease, which, in many cases, does not present the small* 

 est difficulty of diagnosis, may sometimes elude detection and even sus- 

 picion as, for instance, where the patient is already extremely short of 

 breath, and dropsical, and is otherwise wretchedly ill. In the dissection 

 of cases of diseased heart, therefore, we should be prepared to find 

 haemorrhagic infarctions as " accidental discoveries " where their exist- 

 ence has not been suspected. 



The h'quid products of inflammation or of ulceration almost always 

 pass into the circulation with the emboli ; and, while the latter give 

 rise to metastatic infarctions, the former result in the symptoms of 

 pyaemia, septicaemia, intense fever, rigors, purulent inflammation of 

 serous membranes, and the like.* 5 We thus see why most patients with 

 metastatic infarction of the lung are extremely depressed, why their 

 sensorium is blunted by the intensity of the asthenic fever, and why 

 they neither complain of pain in the side or breast, nor show any incli- 

 nation to cough. In most cases there are neither subjective nor objec- 

 tive symptoms of disease of the lung. It is even the rule, at the autopsy 

 of persons who have died of pyaemia and septicaemia during some sup 

 purative or ulcerative process, to find metastatic infarction in the lungs, 

 which, during life, was quite indistinguishable. These latent metastatio 

 infarctions are easily accounted for, if we only call to mind the symp- 

 toms upon which diagnosis of the disease is based. The intense dysp- 

 noea, which appears in cases where large arterial branches in the lung 

 are obstructed, does not exist in metastatic infarction, where the occlud' 

 ed arteries are nearly always very small. Dyspnoea of slighter degree 

 is not noticed by the patient in his stupefied condition. In like manner 

 the characteristic sputum is almost always absent, as generally the 

 patient neither coughs nor expectorates. Finally, notwithstanding 

 their superficial position, metastatic infarctions scarcely ever occasion 

 circumscribed dulness upon percussion, or produce bronchial breathing 

 in the affected region. It is only in very rare cases that patients com- 

 plain of piercing pain in some point of the ohest, and expectorate thin, 

 reddish-brown sputa. If, besides, a friction-sound be audible in the 

 region of the pain, and if the original malady be one frequently produc- 

 tive of metastatic infarction in the lung as, for instance, an injury of the 

 skull affecting the diploe we may pronounce our diagnosis with con- 

 fidence ; but, I repeat, that cases like this are very exceptional. 



* According to recent observations, the introduction into the blood not only of 

 decomposed liquids, but even the absorption of liquid inflammatory products which 

 are not decomposing, gives rise to violent fever, and to secondary inflammatory pro- 

 cesses in distant parts of the body. It would thus seem as though pyaemia, which haa 

 been in some danger of disappearing from the list of diseases, may maintain its placw 

 by side of septicaemia. 



