Definition.—Dilatation of the Bronchial Tubes.
Etiology.—Any condition that impairs the vitality and tonicity of the mucous tissues predisposes to bronchiectasis, for dilatation depends upon a weakened condition of the mucosa, sub-mucosa, and muscular tissues, whereby they atrophy, permitting the weakened tube to dilate.
Age also favors the disease, being most common in adult and middle life. Sex also predisposes to this condition, males suffering much more frequently than females.
The disease is usually the result of chronic bronchitis, chronic phthisis, broncho-pneumonia, emphysema, influenza, and sometimes it is due to measles and whooping-cough.
It may be due to a pressure from an aneurysm or tumors, and where the walls are greatly weakened, the presence of heavy mucus may be sufficient to cause dilatation.
In rare cases it is congenital.
Pathology.—The disease may be general or local, and the dilatation may be cylindrical, saccular, or irregular, all forms of which may be seen in the same lung.
In rare cases, the dilatation is confined to a single tube, and may affect but one side, though usually the entire circumference of the walls share in the change.
The most common form is where many of the tubes are involved, the dilatation commencing at the second or third division, and continuing throughout as a cylindrical or saccular enlargement combined.
The mucous membrane, in rare cases, may remain unchanged, though generally there is thinning or atrophy. Occasionally the mucous membrane is congested and thickened, the result of the inflammatory action. The cylindrical epithelium may be replaced by pavement epithelium.
There is usually a thinning of the muscular tissues, though, in rare cases, there may be thickening due to inflammatory changes. The contents of these cavities vary both in quantity and quality. In some the mucus appears but little changed, though more profuse than in health, while in others it shows great deterioration; in fact, is composed of blood, pus, and not infrequently pulmonary tissue, and casts of the tubes; in such cases it is very fetid. Still in others, the mucus becomes inspissated and sometimes calcified. Ulceration sometimes occurs in the most dependent portion of the cavity. There is usually a diseased condition of the near pulmonary tissue, the change depending largely upon the primary disease causing the dilatation.
Symptoms.—The general symptoms present a wide range, depending upon the primary lesions and enfeeblement of vitality occasioned by them. The most characteristic symptom is the paroxysmal cough occurring in the morning, after a night's rest, to remove the accumulated secretion that has taken place. Change of position, when lying down, may bring on a paroxysm of coughing, by emptying the contents of a cavity into the tube above it.
The expectorated material is usually of a brownish or greenish color, mucopurulent in character, and disgustingly fetid. On standing, it separates into three layers,—an upper, which is brown and frothy; a middle, thin, sero-mucus; and a lower, consisting of granular debris. Examined microscopically, the sputum is found to contain pus cells, oil globules, fatty acid crystals, fragments of lung tissue, and various micro-organisms.
Dyspnea occurs after severe exertion, though respiration is but little disturbed when the patient is at rest. Hemorrhage seldom occurs, though at times the sputum may be streaked with blood.
Physical Signs.—The physical signs depend upon the size of the cavities, their location, superficial or deep, whether empty or filled with secretions, and also the condition of the lung tissue.
Auscultation reveals amphoric sounds where the cavity is large and empty. Mucous rales are heard over various portions of the chest.
Percussion.—After a fit of coughing the cavity is emptied, and percussion at this time gives a high-pitched tympanitic note; when the cavity is full, the percussion note is dull. Deep-seated cavities are not easily detected by percussion.
Diagnosis.—The diagnosis is not always easy, though the physical signs already mentioned should enable one to make but few mistakes. The cavities are to be differentiated from tubercular cavities; but if we keep in mind certain characteristics of each disease, there will be but little difficulty.
The cavity in bronchiectasis is nearly always located in the base of the lung, and the physical signs most prominent posteriorly; while in tuberculosis the cavities are usually found in the apex of the lung, and the physical signs are most prominent anteriorly. Sputum is foul, abundant, and devoid of tubercle bacilli in bronchiectasis. In tuberculosis, the sputum is often blood-streaked, is not so fetid, and is rich in tubercular bacilli. In bronchiectasis there is no fever, no sweating, and the patient is in better flesh. In tuberculosis, fever, night-sweats, and emaciation are characteristic. In one the history is that of bronchitis; in the other, that of tuberculosis.
Prognosis.—Unfavorable as to cure, though the patient may live for years.
Treatment.—The general health of the patient must be maintained, and the administration of the bitter tonics, the hypophosphites, iron, arsenic, and like remedies will form a part of the general treatment. A warm, equable climate is desirable, where the patient can be out of doors the most of the time.
Calcium sulphide will be indicated to counteract the suppurative processes which are continually present. Inhalations of eucalyptus, iodine, creosote, turpentine, carbolic, etc., will correct to some extent the fetid breath, and incidentally benefit the patient.