Asthma Broiichiale. 65 



111 stenosis caused by a foreii^n body tlie exhaled air later 

 on becomes fetid and the temperature rises. In stenosis caused 

 by compression one occasionally also observes edematous in- 

 filtration on account of the simultaneous compression of largei- 

 venous trunks, paralysis of the larynx due to compression of 

 the inferior laryngeal nerve, disturbances of deglutition due 

 to compression of the esophagus, and in ruminants clironic 

 bloating. 



Treatment. Since successful treatment is impossible, the 

 r-:ninals ought to l)e utilized by early slaughtering. 



3. Asthma bronchiale. 



{Asthma sijasmod'u um, Asthma nervosum. ) 



Under this name difficulties of respiration are designated in human 

 medicine which come on periodically in violent attacl<s, being caused 

 by transitory impediments in the bronchioles, and are followed by a 

 return to regular and free respiration. The absence of anatomical 

 changes which might explain the respiratory difficulties points to a 

 nervous origin of the affection. It is looked upon as a neurosis of 

 the vagus and it may have a variety of underlying causes. Irritation 

 of the vagus (pneumogastricus) may be caused by compression 

 (neoplasms, enlarged lymphatics) or by bronchial catarrh or also by 

 reflex irritation in morbid irritability of the nasal or pharyngeal mucosa 

 (transmitted through the trigeminal nerve), or in certain anomalies 

 of the abdominal organs, particularly the stomach and intestines, 

 especially in a catarrhal condition of those organs (asthma dyspepticum). 

 Following upon irritation to the vagus a tenacious secretion is found 

 in the bronchial tree. Tlie smooth muscle fibers of the latter contract 

 convulsively. The bronchial lumen is narrowed, the entrance of air 

 into the alveoli is interfered with and the attack of asthma is brought 

 about. A tetanic contraction of the diaphragm occurs simultaneously, 

 either by reflex irritation through the pneumogastric nerve or in con- 

 sequence of the increase of carbon-dioxid in the blood. Inspiration 

 and expiration are both interfered with during the attack. Signs 

 of acute atelectasis of the lungs are also present and whistling and 

 purring may be heard over the thorax. 



Some veterinary authorities have reported similar eases, the 

 identity of which, with asthma bronchiale, however, cannot be considered 

 as proved, because it had not been considered that transitory stenosis 

 of the air passages may occur and also that severe attacks of dyspnea 

 sometimes occur in the course of permanent stenosis, in emphysema 

 of the lung, in chronic uremia (Lienaux) and in chronic cardiac disease. 



Grebe observed the follo\^'ing symptoms in the case of a horse : 

 During the last ten days the animal had been breathing very heavily 

 at each meal, and this condition lasted for one-half to one hour after 

 the ingestion of food. During the attack the animal betrayed great 

 anxiety, M'as sweating at the head and neck, the mucosae were somewhat 

 cyanotic, the markedly difficult inspiration was accompanied by a strong 

 dilatation of the nostrils and by low whistling sounds; the expiration 

 was easy and free; respiration 28 per minute. The abdomen was 



Vol. 2-5. 



