Page:The American Cyclopædia (1879) Volume III.djvu/317

BRONCHITIS 311 ence to this discrimination, in addition to points of contrast relating to the symptoms, the phys- ical signs obtained by auscultation and percus- sion are to be taken into account. In general terms, the diagnosis rests on the absence of the signs which belong to the clinical history of other affections with which this is liable to be confounded. In ordinary bronchitis, the res- onance or percussion is normal; the murmur of respiration may be weakened, but it is not otherwise altered ; the vocal signs are the same as in health. In short, the only signs belong- ing to the disease are the dry and moist bron- chial rales, and these are often wanting. Phys- ical exploration of the chest is important as enabling the physician to determine that other affections are not present, the diagnosis be- ing thus reached "by way of exclusion." In chronic bronchitis the inflammation is subacute, and more or less persisting. The duration is extremely indefinite ; the disease may continue for months or years, and in some cases it be- comes permanent, lasting until the end of life. The cough varies much in different cases as re- gards frequency and violence. The matter of expectoration also varies much in quantity and character, sometimes consisting of small, solid pellets raised with difficulty, sometimes being muco-purulent or consisting chiefly of pus, and accompanied sometimes with a serous liquid in abundance. The last named character is dis- tinguished as bronchorrhaa. Not infrequently the sputa are streaked with blood. The con- stitutional symptoms are slight or wanting. Symptomatic fever is rare; the appetite and digestion are often excellent; there is either but little emaciation, or the nutrition may be well maintained, and the muscular strength is but little impaired. The affection is thus not incompatible with fair or even good general health. The causes of chronic bronchitis are obscure, except where it occurs in connection with those valvular lesions of the heart which occasion obstruction to the return of blood to this organ from the lungs. This obstruction involves a pulmonary congestion which tends to maintain, if not to originate, subacute bronchial inflammation. Bronchorrhoea is apt to occur in these cases, and the transudation of serum affords some relief of the pulmonary congestion. With or without this causative connection, an abundant bronchial expectoration, having ex- isted for a long period, becomes sometimes, as it were, an element of health, patients suffer- ing from a sense of oppression when from any cause the expectoration is notably diminished. It follows from the statements just made, that a chronic inflammation of the bronchial tubes is not usually in itself a serious affection. It may however lead to more or less impairment of health, diminishing the ability to resist or recuperate from other and graver diseases. It may even prove the immediate cause of death when, from the feebleness incident to old age or some coexisting grave disease, the ability to expectorate is impaired. Under these circum- stances, the accumulation which takes place in the bronchial tubes may be sufficient to cause suffocation. Moreover, it proves in some cases remotely serious by leading to other pulmonary affections, namely, emphysema, or dilatation of the air vesicles, and asthma. Chronic bron- chitis generally enters into the causation of these two affections. As a compensation, in leading to these affections, it antagonizes an- other affection of a much graver character, namely, phthisis or consumption. To the lat- ter affection it does not tend even in the cases in which emphysema and asthma do not be- come developed. Chronic bronchitis is to be differentiated, in medical practice, from phthisis or consumption. In making this discrimina- tion, the physician relies chiefly on the absence of the symptoms and physical signs which should be found if phthisis or consumption ex- isted ; that is, he reasons " by way of exclu- sion." There are certain remedies which are useful, and sometimes curative, in chronic bronchitis. The iodide of potassium, the mu- riate of ammonia, the bromides, and balsam of copaiba are remedies, the utility and some- times the curative power of which experience has established. A sea voyage in warm lati- tudes may prove signally beneficial, and may effect a cure. Patients residing in a change- able, cold climate, may derive benefit, and per- haps recover, by removing to one more uniform and genial. The cough is sometimes relieved, expectoration facilitated, and permanent im- provement effected, by the inhalation of vapor or spray formed from medicated liquids. The fact that bronchitis is one of the symmetrical diseases has been stated. This is a law of the disease when it is not secondary to some other pulmonary affection. Exceptions to this law obtain when the bronchitis takes place in the course of pneumonia and tuberculous disease of the lungs. Its occurrence as secondary to these affections is quite constant, and under these circumstances the bronchial inflammation may be more or less limited in extent, and confined to one side, that is, unilateral. The disease is then distinguished as " circumscribed bron- chitis." Capillary Bronchitis. This is an im- portant variety of the disease produced by an extension of the inflammation from the large bronchial tubes to those of smaller size. It is attended with great danger to life ; indeed, in a large proportion of cases, it ends fatally. The danger consists in the obstruction incident to inflammation of the tubes of small size, and caused by the swelling of the inflamed mem- brane and the presence of mucus. The danger is greater than in pneumonia, which may for the time render useless one half of the pul- monary organs. The interference with the function of respiration is greater in the so- called capillary bronchitis, because this, like ordinary bronchitis, affects equally both sides ; that is, it is bilateral, and hence the respiratory function is compromised more than when an en- tire lung is rendered useless. Death takes place