PUI.MONARY CEDEMA. 



Causes, pneumonia, extra force of right heart or weakness of left, insufiS- 

 ciency of mitral valves, deflection of blood by obstruction in one portion of 

 lung, pressure of tumor on pulmonary veins. Malignant oedema. Malig- 

 nant catarrh. Bright's disease Anaemia. Paiasitism. Symptoms, ab- 

 normal heart sound, or urinary secretion. Parasitism. Percussion shows 

 flat sound, auscultation lowered, respiratory murmur, heightened blowing. 

 No crepitation. Expectoration serous. Prognosis grave. Treatment, 

 attack primary disease. Posture. Elimination. Dry cupping. Heart 

 tonic. 



A dropsy of the lung tissue may supervene in weak conditions, 

 in the course of inflammatory disease of the lungs ; it may also 

 depend on an imperfect balance in the forces of the right and left 

 heart respectively, which leads to the habitual throwing of blood 

 pressure back upon the lungs. Still more frequently the conges- 

 tion and dropsy depends on insufficiency of the mitral valves by 

 reason of which a reflux of blood toward the lungs takes place 

 at each heart-beat. The pressure of tumors on the pulmonary 

 veins maj' have a similar action. Obstruction of circulation in 

 one portion of lung may cause an extra blood pressure on an 

 adjacent one, and oedema so caused may be found especially in 

 cattle and pigs in which the interlobular connective tissue is 

 specially abundant. This may be seen in miliary tuberculosis in 

 cattle, and it probably contributes to produce the extraordinary 

 liquid collections that characterize lung plague. In cattle also 

 malignant cedema or hasmorrhagic septicaemia may affect the 

 lung, and an cedematous condition is sometimes met with in 

 malignant catarrh. Bright's disease is another cause, the ursemic 

 dropsy finding a favorite seat of election in the loose lung tissue 

 unsupported by solid tissues. The ansemia resulting from para- 

 sitism like distomatosis may similarly affect the lung. 



The symptoms of pulmonary cedema will usually be compli- 

 cated by those of the affection causing it. Thus modification of 

 the first heart sound or of the urinary secretion, or the existence 

 of parasitism, would furnish valuable indications. 



The physical signs of lung disease vary. If pneumonia is 

 present it is betrayed by its characteristic symptoms. In the ab- 



243 



