140 DISEASES OF THE PARENCHYMA OF THE LUNG. 



when we reflect that in passive congestion (Blut-stauung) the circular 

 tion is as much retarded as in fluxion it is accelerated, that in the former 

 a double cause of dyspnce aprevails, in the latter but one. Intense 

 dyspnoea and all the symptoms of pulmonary apoplexy and suffocative 

 effusion, which we have described, are often suddenly and unexpectedly 

 added to the constant shortness of breath of disease of the heart. Effu- 

 sion into the air-vesicles now exists beside swelling of their walls ; the 

 respiration, merely impeded hitherto, has now become inadequate. A 

 great number of those who have disease of the heart die of acute passive 

 congestion and acute oedema, without discoverable cause for the sudden 

 increase in the impediment to the circulation. In other cases the symp- 

 toms of effusion of serum into the pulmonary vesicles, the inadequate 

 respiration, and final death of the patient, take place more gradually in 

 cases of disease of the heart. 



If, in the course of an asthenic fever, whether it be a symptom of 

 typhus or of pyaemia, the respiration should become shallow and incom- 

 plete, should percussion indicate a condensation of the parenchyma of 

 the lung, near the spinal column, should sputa be ejected more or less 

 tinged with blood, we have to do with an obstructive engorgement of 

 the lung with hypostasis or with its sequelae. 



It would be unnatural and artificial to make a distinction between 

 the symptoms of hyperaemia and of cedema. If a hyperaemia be intense, 

 cedema occurs as one of its most important symptoms. We infer that 

 this normal and necessary result has taken place, in the first place, from 

 the grade of the dyspnoea, which never becomes so severe from swelling 

 of the alveolar walls alone, as from cedema. Almost universally where 

 hyperaemia has produced death, serum has been found in the air- 

 vesicles. 



The characteristic sputa give a second point for diagnosis. Such 

 liquid secretion is seldom or never discharged from the bronchial mu- 

 cous membrane, and the expectoration of liquid transparent, profuse, 

 sputum, more or less mixed with blood, if it supplant the viscid, scanty 

 nputum of pneumonia, is very properly regarded as of serious omen. 

 Auscultation also gives information as to the occurrence of oedema. A 

 dry rdle, that is to say, a rdle which is formed in viscid fluid, may easily 

 be distinguished from a moist one, that is, from a rattle which takes 

 place through the medium of a thin liquid. In the secretion of the 

 bronchial mucous membrane we seldom hear such moist rattling sounds 

 occur as those which arise when the serous transudation of the vesicles 

 fills up the bronchi. In other cases we hear no respiratory sound in 

 spots at which the vesicles are filled up by cedema, and where no air 

 can enter. Bronchial breathing is only to be heard in rare instances.* 

 * Bronchial Breathing takes place when the vesicles, filled with serum, do noi 



