150 Pulmonary Gangrene. 



Fo<^i situated near the pleura frequently lead to a purulent 

 or putrid pleurisy, or pneumothorax develops after the focus 

 breaks through. The internal organs present the signs usually 

 found in grave general infection, such as parench^anatous and 

 fatty degeneration, occasionally also hemorrhages and metas- 

 tatic foci. 



Symptoms. The earliest s>Tnptom of pulmonary gangrene 

 is usually a peculiar, sweetish, foul, very disagreeable smell of 

 the exhaled air. Stinking gases are developed in consequence 

 of the putrefactive processes ; these escape with the exhaled air 

 and are at first noticeable only in the immediate neighborhood 

 of the nose of the animals ; later on they pervade the air of the 

 neighborhood and can be smelled at once upon entering the place 

 Avliere the patient is kept. This smell may, however, be absent 

 in pulmonary gangrene, if the focus has remained closed and has 

 no communication with the outside world through the air pas- 

 sages. 



As soon as gangrenous foci have broken into bronchi, there 

 appears a dirty-grayish red, eventually ])rown-red or greenish 

 tenacious nasal discharge, which becomes verj^ abundant after 

 coughing or after lowering of the head and which always dis- 

 seminates the disgusting smell. Microscopically, the nasal dis- 

 charge (Fig. 23) shows granular tissue, detritus, fat droplets, 

 needle-shaped fat crystals, l^rown or black masses of pigment, 

 sometimes pus corpuscles, red blood corpuscles, numerous varie- 

 ties of bacteria, and elastic fibers, occasionally in alveolar ar- 

 rangement. (Elastic fibers can easily be demonstrated after 

 boiling the exudate in 10% solution of caustic potash, followed 

 by centrifuging.) 



Corresponding to the extent of the inflammatory process, 

 the respiration is difficult and accelerated ; this becomes par- 

 ticularly marked after a general septic infection of the organ- 

 ism has taken place. 



The percussion sounds remain unchanged if central por- 

 tions of the lung are affected exclusively. Frequently, however, 

 we hear dullness, and occasionally also tympanitic sounds in 

 the anterior and inferior pulmonary portions. The formation 

 of cavities may sometimes be diagnosticated if elastic t^nnpanic, 

 or metallic sound, or cracked pot sounds are found in a circum- 

 scribed place of the thorax, associated with metallic rfdes and 

 bronchial breathing; these correspond in pitch with the tym- 

 panitic percussion sound. Splashing and similar noises are 

 also characteristic of the existence of pulmonary cavities. 



Pulmonary gangrene is almost always accompanied by 

 fever. Its intensity varies from case to case, but it usually 

 reaches above 40° C. and shows a remittent type (see Fig. 24) ; 

 an insignificant fever is often seen at first for several days in 

 aspiration pneumonia. The pulse becomes accelerated, small, 



