A system of practical medicine. By American authors. Vol. 3

by Unknown

Under similar circumstances, if the patient's strength will admit of it, great benefit will sometimes result from a mercurial purge, by which passive congestion of the portal system may be relieved and the upward pressure of an engorged liver in some degree lessened.

4. Atrophic Lobar Emphysema.

This disease differs from the hypertrophic form of emphysema in the circumstance that the bulk of the affected lungs has undergone diminution from waste or atrophy of their tissue. Absolutely, the lungs may contain no more air than they should in health—they may even contain less—but, relatively, there is an increased amount of air in them in consequence of the diminished amount of the lung-tissue. Such relative increase of air in a given area of the lung may be very considerable from the atrophy and destruction of the cell-walls, the alveoli coalescing so as to form cavities, while the individual air-cells are not dilated. The entire lung, however, is shrunken, the chest-wall correspondingly depressed and contracted, and the thoracic muscles atrophied. The function of the affected lungs is impaired in consequence of their loss of size and the diminution of the respiratory movements. This is of course especially noticeable when exertion is made, while under other circumstances there may be little or no embarrassment of breathing unless the disease is far advanced and has involved a large amount of both lungs. But, in general, this form of disease causes less distress and is a less formidable affection than hypertrophic emphysema. In some cases a mingling of the two forms is found, as when a person the subject of general atrophic emphysema has a local vesicular dilatation developed at the top and margins of the lungs.

The shrunken state of the lungs in atrophic emphysema prevents the heart from being overlapped, so that the area of cardiac dulness is not lessened, as it is in the hypertrophic form; and as the general waste of the system is attended with a diminution of the amount of blood, dilatation of the right ventricle, and consequent dropsy, are not apt to occur, as they are in hypertrophic emphysema.

ETIOLOGY.—Atrophic emphysema is always due to constitutional causes. It is found chiefly in old persons or in those in whom impaired nutrition has produced the degenerative changes of old age. Hence it is described by some writers as senile emphysema or senile atrophy of the lungs.

SYMPTOMS.—Of the general symptoms of atrophic emphysema, apart from those which belong also to the hypertrophic form, the most marked are—first, the lessened size of the thorax; and, second, the character of the dyspnoea, which is not urgent, and is not apt to occur except on making exertion. The blood is lessened in amount from the general impairment of nutrition, and is therefore adapted, so to speak, in quantity to the diminished aërating space. Percussion in general gives exaggerated resonance, from the relative increase of air in the lung and the thinness of the thoracic wall, which thus vibrates more perfectly. In some cases, however, from loss of elasticity in the cartilages of the ribs, the resonance is even diminished. On auscultation there are found somewhat prolonged expiration and, in general, feeble inspiratory murmur—signs which belong also, but in greater degree, to true hypertrophic emphysema, from which, however, the atrophic form is to be distinguished by the contraction of the chest that is seen throughout its entire contour.

In some cases of hypertrophic emphysema there may be, it is true, an appearance of partial contraction of the chest-wall, since where the emphysema has produced a marked bulging of the upper portion of the thorax the part below may seem by contrast to be contracted. But in the atrophic form of the disease no distension is seen at any part of the chest-wall, the whole surface being more or less sunken and contracted. Even in hypertrophic emphysema with distension of the thorax, when the disease has lasted a long time there may be some degree of wasting of the lung-tissue; but this condition does not constitute true atrophic emphysema, which is such from the beginning without any preceding stage of hypertrophy.

DIAGNOSIS.—The diagnosis of atrophic emphysema is to be made by the physical signs studied in connection with the conformation of the chest.

PROGNOSIS.—The prognosis of this affection is hopeless as regards a cure, since the organic change is due to the degeneration of age; yet the disease may continue for years without materially or at all affecting the duration of life.

TREATMENT.—The atrophied lungs can never be restored to their integrity; treatment is therefore limited to the use of tonics and nutriment in order to hold in check the process of waste; and to the relief of bronchial catarrh, which is apt to be attended with profuse purulent secretion. The agents best suited to these two purposes have already been considered.