Definition:—This condition is one in which air has found its way into the pleural cavity. It is seldom, however, that air is found in the plural sac without an effusion of serum or without the presence of pus, or both. These conditions, to be correctly expressed, are known as sero or hydro-pneumothorax, or pyo-pneumothorax. It may follow ulcerative processes which result from severe inflammation, or it may occur as the result of common injury, as puncture of the chest wall or compound fracture of the ribs.

Symptomatology:—The condition usually occurs with suddenness, with pronounced difficulty of breathing, resulting from oppression of the lungs, acute, unbearable pain in the side and quickly developing cyanosis. It is possible for the air to enter the pleural cavity so rapidly, through even a small opening, as to expel the air from one lung completely, causing collapse, profound shock and perhaps sudden death. Usually the progress is not sufficiently rapid to induce such immediately serious symptoms. The aspiration becomes progressively shorter, as if there were a great weight upon the chest, the pulse becomes very fast, small and easily compressible, feeble and thready. While there is usually an increase of fever it often happens that the temperature becomes subnormal, falling to 97° or even 96.5° F. Upon percussion, instead of the dulness of effusion, there is a marked tympanic sound present over the entire distended area. If a fluid is present and the patient is raised into a sitting posture, dulness will be observed, from below upward, in proportion to the quantity of the fluid. The sounds present in a normal condition over the region of the liver, heart or spleen are positively altered by the presence of air, which displaces these organs to a certain extent.

Prognosis:—The condition is always serious and apt to be fatal when following other protracted disease.

Treatment:—For immediate relief, if the diagnosis is positive, the air above any fluid that may be present should be evacuated through a hypodermic needle of small caliber. It will escape with sufficient rapidity, as sudden evacuation could readily be serious. The fluid may be drawn off by aspiration. Other conditions should be treated symptomatically. The indications must be met promptly, and any tendency to collapse or sudden prostration, should be treated with active hypodermic stimulation.

The Eclectic Practice of Medicine with especial reference to The Treatment of Disease, 1910, was written by Finley Ellingwood, M.D.