Emphysema and tuberculosis are some times co-existent. The former may suc ceed the latter or have preceded it. In the first ease it is limited; in the latter it is often accompanied by chronic pneumonia. Potain (La Sem. Mad., July 9, '90).
The lung-tissue pits readily on press ure.—one of the most marked features, according to Osler; and to the touch it conveys what he terms a "downy, feathery feel." The same author de scribes the morbid changes in the air vesicles and bronchi as follows: "Be neath the pleura greatly-enlarged air vesicles may be readily seen. They vary in size from to 3 millimetres; and irregular the size of a walnut or larger, may project from the free mar gins. The best idea of the extreme rarefaction of the tissue is obtained from sections of a lung distended and dried. At the anterior margins the structure may form an irregular series of air chambers, resembling the frog's lung. On careful inspection with the hand lens, remnants of the interlobular septa or even of the alveoli may be seen on these large emphysematous vesicles. Though general throughout the organs. the distension is more marked, as a rule, at the anterior margins, and is often specially developed at the inner surface of the lobe near the root, where in ex treme cases air-spaces as large as an egg may sometimes be found. Microscopic ally there is seen atrophy of the alveolar walls, by which is produced the coales cence of neighboring air-cells. In this process the capillary net-work disap pears before the walls are completely atrophied. The loss of the elastic tissue is a special feature. It is stated, indeed, that in certain cases there is a congenital defect in the development of this tissue. The epithelium of the air-cells under goes a fatty change, but the large dis tended air-spaces retain a pavement layer.
"The bronchi show important changes. In the larger tubes the mucous mem brane may be rough and thickened from chronic bronchitis; often the longitudi nal lines of submucous elastic tissue stand out prominently. In the advanced cases many of the smaller tubes are di lated, particularly when, in addition to emphysema, there are peribronchial fibriod changes. Bronchiectasis is not, however, an invariable accompaniment of emphysema, but, as Laennec remarks, it is difficult to understand why it is not more common. Of associated morbid
changes, the most important are found in the heart. The right chambers are dilated and hypertrophied, the tricuspid orifice is large, and the valve-segments are often thickened at the edges. In ad vanced cases the cardiac hypertrophy is general. The pulmonary artery and its branches may be wide and show marked atheromatous changes." already stated, change of residence to an equable and warm climate is of great value, especially in cases characterized by bronchitis and asthma. Any stenotic disorder of the naso-pharynx should be corrected and the patient should give careful attention to the bowels and receive nutritious, though easily digested, food. While no remedy is known to greatly influence the disease, much may be done to relieve the pa tient's discomfort. Pressure upon the abdomen by means of an abdominal belt is sometimes helpful (Berdez). Oxygen inhalations are also of great value, 2 or 3 gallons being administered three times a day (Reid, Skerrit). As an internal remedy, none is better than strychnine, the dose being gradually in creased. Urgent dyspncea and lividity occurring in young and vigorous subjects are bled by Osler, who states that he has saved lives in so doing. Aspiration of the air in large cavities has been used with success by Wigmore.
When the heart begins to fail, rest in bed is required, and, if this does not overcome the oedema, digitalis should be given. Three to 4 '/, grains of the pow der, preferably in the infusion, are given the first day, and continued until two quarts of urine are passed in twenty-four hours, or until the action of the drug is indicated in the pulse (Liebermeister).
Senile, or Atrophic, Emphysema.—In this form of vesicular emphysema, care fully studied by Jenner, the alveolar septa become atrophied and large air spaces are formed; the atrophy being general, though irregularly progressive, the organ becomes reduced in size, thus constituting "small-lunged of Jenner; and contraction of the chest wall—which is not always perceptible— constitute about all the symptoms, and even these are usually hidden by those of catarrhal tracheo-bronchitis, from which these patients almost always suf fer. As implied by its name, the dis ease is one of old age.