64: DISEASES OP THE TRACHEA AND BRONCHI. 



doubtful if an infection like that of the acute exanthemata be the cause 

 of this complaint, to which it bears a certain similarity. Such an epi- 

 demic, the "grippe," or influenza, appeared in the year 1732, and ; 

 travelling through Europe, from east to west, attacked at least one half 

 of its population. The disease was a dangerous one, especially for chil- 

 dren and for old persons, partly from the intensity of the fever, partly 

 through extension of the local affection into the pulmonary alveoli, and 

 partly from participation of the intestinal mucous membrane in the com- 

 plaint, and from other complications. Since that time there have been 

 repeated epidemics of influenza, particularly in 1800 and 1835. With 

 this repeated reappearance of the malady, the vicious custom has gradu- 

 ally crept into use, both among physicians and people, of calling all the 

 non-epidemic bronchial catarrhs influenza, when associated with violent 

 general disturbance, and showing unusual obstinacy, or when the intes- 

 tinal canal takes part in the disorder, using the term gastric influenza 

 (gastrische Grippe). This bad custom has, in one respect, its advan- 

 tage. No one suffering from a mere catarrhal fever is willing to consider 

 himself seriously ill, or to keep his bed. For an attack of " influenza," 

 however, he is content to lay up for a week or ten days. 



Finally, we must observe that, in very many cases, the exciting 

 causes of catarrh are unknown, unless we accept the explanation with 

 which people usually content themselves, that " they must have taken 

 cold somewhere." 



ANATOMICAL APPEAKANOES. In the cadaver, acute catarrh of the 

 trachea and bronchi leaves a redness, sometimes diffuse, sometimes 

 mottled, the one being due to injection, the other to ecchymosis. The 

 mucous membrane has a clouded look, is opaque, relaxed, and tears 

 easily. This condition arises from infiltration occasioned by the aug- 

 mented pressure of the blood within the capillaries. Owing to this 

 oedema of the mucous membrane in which the submucous tissue partici- 

 pates, the calibre of the bronchi is reduced. The younger the subject, 

 the smaller the calibre of the tubes, so much the more readily does 

 tumefaction of the mucous membrane impede or prevent access of air 

 into them, especially into those of the third and fourth magnitude. This 

 is an important fact in symptomatology, particularly as regards the con 

 trast between the symptoms of bronchitis in childhood and that in adults, 

 and in the difference of the danger from the disease at the two periods. 



At first the mucous membrane is dry, or covered with a scanty, 

 tenacious, transparent secretion, containing but few young cells, and a 

 very few mature detached cells of ciliated epithelium. Somewhat later 

 an active development of cells usually takes place upon the surface, the 

 product of which, when mingled with the secretion, now more copiously 

 and freely poured out, imparts to it a turbid, yellowish appearance. 



