148 Pulmonary Oaiiiireue. 



va^'us i)iiGiinionia, following- it, is (lepcndeiit upon anosthosia of 

 the larynx and the air passag'es, and upon paralysis of the mus- 

 cles of the larynx, which makes the removal of the foreign 

 bodies that might get into the larynx impossible. Nu- 

 tritive disturl)ances of the puhnonary tissue may, ac- 

 cording to Bettini, likewise take part in it. The sud- 

 den entrance of larger amounts of fluid into the pharynx 

 may likewise give rise to aspiration as occurs in the 

 breaking of a peri- or retropharyngeal abscess, in ob- 

 struction of the esophagus, during vomiting, in sudden falling 

 down of cattle, in malignant foot-and-mouth disease; also in 

 consequence of the protrusion of the contents of the paunch. In 

 protracted labor a fetus sometimes aspirates amniotic fluid that 

 is already contaminated. Foreign bodies, such as ears of grain, 

 pieces of wood, hairs, are sometimes aspirated. In the pleural 

 cavity of a dog, found dead from pulmonary gangrene, Mori 

 once found six ascaris worms. He believed that they had been 

 aspirated in vomiting and had gotten into the lungs and from 

 there into the pleural cavity. 



Artificial feeding or the administration of liquid medicines 

 may become dangerous in more serious disturbances of degluti- 

 tion. Pneumonia caused by aspirated medicines may occur 

 without the simultaneous existence of disturbances of degluti- 

 tion (drenching pneumonia, pneumonia medicamentaria), if 

 the medicines are administered awkwardly, if they are given at 

 one time in too large doses, if the tongue is pulled out, or the 

 nares are closed, if the head is held too high, if the drenching 

 is continued in spite of cough or squealing (in hogs), if the 

 fluid is poured into the nose, if the medicine cannot be swal- 

 lowed easily, or if it produces attacks of cough. 



Various, including putrefactive, bacteria, which in such 

 cases have gained access with the aspirated substance into the 

 bronchi, then multiply and produce first a severe inflammation 

 in the bronchial wall, and the inflammatory process may be fol- 

 lowed by necrosis and putrefaction. The inflammation spreads 

 through the bronchial wall and also along it into the pulmonary 

 parenchyma ; here it produces catarrhal and hemorrhagic in- 

 flammation and soon also necrosis and putrefaction. 



Of the various types of pneumonia, croupous pneumonia of 

 horses and swine, preferalily and comparatively frequently 

 passes into pulmonary gangrene; catarrhal pneumonia leads 

 less frequently to this process. 



The contents of abscesses and caseous foci (tuberculosis, 

 echinocoecus, etc.) may liecome putrid; bacteria which have 

 entered with the inhaled air are then responsible for this pro- 

 cess. Infected emboli may carry the organisms (in Nielsen's 

 case bacillus necrophorus) from other gangrenous or ulcerating 

 organs into the lungs. 



Injury to the lung may directly become the cause of pul- 

 monary gangrene if putrefactive bacteria gain entrance at 



