90 DISEASES OF THE TRACHEA AND BRONCHI. 



ed by Wintrich, who, rejecting the theory of bronchial spasm, as- 

 sumes a tonic cramp of the diaphragm as its prime cause. In sup- 

 port, he relies upon the negative results obtained in attempting to 

 produce spasm of the bronchi by irritation of the trunk of the va- 

 gus (which however is balanced by the positive results had by other 

 experimenters), and also upon the permanent depression of the dia- 

 phragm observable in asthmatic cases. But, according to Jliermer, 

 this depression, which indeed always exists in asthma, is not the re- 

 sult of tonic spasm of the diaphragm (which latter only occurs in 

 tetanus, causing symptoms of asphyxia, and not of dyspnoea), but is 

 rather the effect of a so-called " pulmonary flatulence " due to an 

 increased amount of air which the lungs are made to retain by the 

 spastic contraction of the bronchi. The point made by Wintrich 

 and Bamberger, that if asthma depend upon bronchial spasm the 

 lungs should be contracted and the diaphragm drawn up, is met by 

 Biermer with the retort that this could only follow supposing that 

 the spasm beset not only the bronchi but the lungs, and that the 

 pulmonary vesicles took part in the contraction. 



Nervous asthma is a rare disease, which now and then attacks 

 the young, but more commonly those of middle age. Men are more 

 often effected than women, although it sometimes appears as a 

 symptom of hysteria. In some families there is a distinct heredi- 

 tary tendency to the disease. The inducing cause of an attack is 

 ascribed by the sufferers (too fancifully, no doubt, in many cases) 

 to the most diverse and accidental influences. We hear of some 

 who never suffer unless in some particular abode ; of others who are 

 never exempt unless they live in some special locality. Generally 

 the utmost foresight fails to guard against a return of the disease.] 



ANATOMICAL APPEARANCES. As we have seen, it is only in the 

 rarest instances that we are able to find structural changes in the 

 cadaver to which the symptoms of bronchial asthma can be attrib- 

 uted without dispute. Indeed, in order to warrant a diagnosis of 

 pure bronchial asthma, the bronchial mucous membrane should ap- 

 pear healthy, nor should any other cause for the dyspnoea be discov- 

 erable at the autopsy. 



SYMPTOMS AND COURSE. Bronchial asthma, like other nervous 

 diseases, has a typical course, in which paroxysms alternate with 

 intervals of exemption, although its type is seldom a regular one. 

 Asthmatic attacks sometimes follow one another with short pauses 

 for a while, and then subside, often not again to return for months, 

 or even years. 



Should the paroxysm come on during sleep, the slumber becomes 

 restless, and the as yet unrecognized sensation of dyspncea gives 



