252 Nouveau Dict. Méd., vol. xxviii.

Hæmothorax.

DEFINITION.—Accumulation of blood in the thoracic cavity unconnected with inflammation of the pleuræ.

ETIOLOGY.—Hæmothorax may be caused by traumatic injuries, by the bursting of an aneurism, from ulceration through the walls of the aorta of the vena cava, or from the veins of the pleura. It may be caused by laceration of the intercostal arteries in penetrating wounds. In very rare cases a profuse bleeding takes place in caseous pneumonia or in gangrene of the lungs, and bursts into the pleural cavity (Fraentzel). Cancer of the lung or pleura may, by pressure, produce absorption and destruction of the walls of the blood-vessels, and cause discharge of their contents into the pleural cavity. Sir Thomas Watson253 reports a case where enormous hæmothorax caused enlargement of the left side, pushing the heart to the right of the sternum from caries of two ribs with ulceration through an intercostal artery. The blood never escapes from the lung into the pleura when there is considerable pulmonary apoplexy.

253 Practice of Medicine, vol. ii.

PATHOLOGICAL ANATOMY.—Blood is found coagulated to a greater or less degree in the pleural cavity, and the lesion producing the hæmothorax can generally be found; the remains of blood may be found even after it has been some time effused. If the hemorrhage does not prove fatal, it may all be absorbed, or it may by its presence cause local inflammation of the pleural membrane.

SYMPTOMS.—The symptoms are those of perforation into the chest—sudden intense pain on the diseased side, with internal hemorrhage, great pallor, feeble circulation, cold extremities, and syncope. Patients often die in a few minutes. If the hemorrhage is moderate in quantity, they revive and the circulation returns, but they complain of feelings of suffocation and oppression. Slowly the general strength returns and the patient recovers.

SEQUELÆ.—Most modern surgeons admit that serious hemorrhages into the pleura come from the thoracic walls, or from the blood-vessels in the neighborhood of the hilum, or from those which accompany the bronchial diseases of the second or third order. Hæmothorax is always consecutive to some primary lesion. Where it is caused by penetrating wounds or by the bursting of blood-vessels in the lungs, air enters the cavity and becomes mixed with the blood, producing a complication in the form of hæmato-pneumothorax. This frequently gives rise to pyo-pneumothorax with a collection of purulent and ichorous fluid.

DIAGNOSIS.—The previous history of the case, together with the characteristic symptoms we have mentioned, enables us to diagnose hæmothorax from pneumothorax, which commences in a similar way. The only other condition likely to be confounded with it is effusion in pleurisy, the physical signs of which are somewhat the same. If the blood remains uncoagulated we shall have absence of vesicular murmur, with dulness on percussion, absence of fremitus, and no friction sound. The introduction of a fine hypodermic needle enables us to be certain of the nature of the fluid.

The PROGNOSIS is always serious. If the cause of the hemorrhage is the bursting of an aneurism, death supervenes in a short time. Hæmothorax, when caused by penetrating wounds, unless they produce hemorrhage, is not necessarily serious. The blood may entirely disappear in a few weeks. Entrance of air with the blood renders the prognosis more serious. Secondary pleurisy is not ordinarily severe unless pus forms.