Injuries to the Mediastinum and Tho racic Vessels.—Rarely existing alone, these injuries often complicate injuries of the heart or lung, obscuring their symptoms and depressing the prognosis. When the great vessels are injured, im mediate and fatal haemorrhage results. Such later complications as aneurism and mediastinal abscess have been de scribed elsewhere.
Wounds of the thoracic duct, while they prove fatal through leakage of the chyle, are said to heal if the duct is not completely divided on account of the unusual elasticity of its walls.
Reports of 9 cases of wounds of the thoracic duct have been collected from literature. Personal case which occurred during a secondary operation for re moval of cancerous glands in the neck.
As a rule, the thoracic duct lies be yond the reach of operative injury. The most important anomaly from a surgical stand-point is an arching of the duet high up into the neck.
The treatment of injuries to the tho racic duct occurring during operation. may be summed up as follows:— "When working near the duct all visi ble lymphatics should be tied.
"If the duct itself is injured, suture is the ideal method." If this is impossible and the duct wounded seems to be the main branch, a provisional ligature should be applied and the wound tarn poned with gauze. If the leakage should become uncontrollable and threaten starvation, the provisional ligature should be tried. H. W. Cushing (Annals of Surg., June, '98).
III. Primary Complications. Hemorrhage.
—1. External hemorrhage. —This merits no extended notice. Ex ternal hmmorrhage, whether slight or profuse, may come from a visceral in jury, quite as internal hemorrhage may come from a parietal vessel.
2. Internal Hcemorrhage.—The blood may be effused into (a) the bronchi [causing hrernoptysis], (b) the pleura [hremothorax], (c) the pericardium [hmmopericardium], and (d) the medi astinum [hremomediastinum]. Any or all of these manifestations of bleeding may result from a single injury.
— The general symptoms of internal hmmorrhage are the symp toms of a rapid loss of blood plus those of the attendant shock, viz.: collapse, usually syncope, with ever-increasing anaemia and progressive weakening of the pulse, in spite of the most energetic stimulation. To this not ovcrdefinite clinical picture are added, when the haemorrhage is intrathoracic, certain characteristic physical signs. An lue moplysis is the most frequent, and the most notable evidence. It may be dis
tinguished from hrematemesis by the presence of riles in the bronchi of the affected lung (perhaps in both), the his tory of injury to the chest, and the light color of the blood as well as its admixt ure with air. Memothorax stands next in importance. It produces the same physical signs as pleurisy with effusion (which see), unless there is a simulta neous irruption of air into the pleural cavity, in which case the signs are those of pneumohnemothorax (see below). llainopericardium increases the area of cardiac dullness and interferes with the action of the heart quite as a serous peri carditis does. Finally hcemomediastinum produces physical signs similar to those of abscess (see illEniasTINum).
DIAGNOSIS.—The diagnosis is rarely doubtful. It may always be settled by paracentesis of the pericardium or pleura (see below). But the point of origin of the hmmorrhage may be diffi cult to determine. On this point a few fundamental rules may be laid down.
1. If there is hfemoptysis, there are usually more riles in the injured lung than in the sound one.
2. If there is luemothorax or pneumo hemothorax without luemoptysis, the lung is intact and the bleeding parietal usually.
3. IIremopericardium is no proof that the heart itself is wounded.
4. Never remain in doubt whether there is bleeding in the chest-wall. Be assured by actual inspection that there is no haemorrhage from an intercostal or an internal mammary artery, even en larging the flesh wound for that purpose; for death has occurred too often from such hemorrhage, which may perfectly well be controlled.
– The cause of the great loss of blood is in all cases the same. While clotting is retarded or entirely prevented by the incessant movements of the chest and the organs within it, the blood is actually sucked from the vessel by the aspiration of the intratho racic tension. The effect of this aspira Eon is of no great importance when the bleeding is into the pericardium or the mediastinum; but it plays an important role in pleural effusions, the tension of the normal lung and the size of the pleural cavity being such that the effu sion of blood within it may fill half the thorax before the tension is equalized, and having gone thus far it is liable to go still farther and compress the heart and the other lung.