Increasing embarrassment of the heart’s action, which is not caused by the collection of blood, may be due to pyopericardium. So soon as the physical signs indicate gradual enlargement of the cardiac area the exploring needle should be used. A traumatic pericarditis may simply require aspiration of the pericardium, whereas the presence of pus in the pericardial cavity will not only necessitate aspiration, but occasionally open incision, with or without drainage. The appropriate manner of affecting these procedures will be found more fully discussed in the section on the Heart.
INJURIES TO THE THORACIC VISCERA.
In general, and without regard to the nature of the accident, injuries to the thoracic viscera include wounds of the pleura, the lung, the diaphragm, the various large and small vessels, the pericardium, the heart, the thoracic duct, and the nerves.
Wounds of the Pleura.
—Injuries to the pleura, including rupture, are produced by severe blows which do not inflict fractures, although these are rare in the absence of such injuries. They are usually not accompanied by external markings, but are indicated rather by dyspnea and cough, with involuntary limitation of respiratory motions and by the physical signs of escape of blood (hemothorax) or air (pneumothorax), or by some crepitation at the site of fracture, which may be recognized with the stethoscope. In many instances lacerations of the pleura are accompanied by more or less injury to the lung, perhaps with perforation of air cells or small bronchi and the inevitable pneumohemothorax. With a wound situated near the twelfth rib the lung, which extends normally only to the tenth, may escape injury. A small wound of the pleura is of little consequence. By itself it is of serious import only as it is accompanied by more serious disturbances of the lung which it envelops, or the heart which it contains.
When air passes freely to and fro through the opening in the chest wall, without expectoration of froth or bloody mucus, it may be assumed that the lung itself has not been injured. To this condition the name traumapnea has been given.
Uncomplicated cases of pneumothorax usually take care of themselves, the air being gradually absorbed by the bloodvessels. In certain cases this air may be withdrawn by the aspirator. A small amount of blood within the pleural cavity is usually absorbed. An amount sufficient to embarrass respiration should be withdrawn either with the aspirator or by incision. For the latter purpose the wound may be utilized when properly situated.
Wounds of the Lung.
—Wounds of the lung are made immediately dangerous by injury to its bloodvessels or are given a serious aspect by the possibilities of various forms of infection, including septic pneumonia. In serious cases this may proceed to abscess formation or gangrene. Should either of these be sufficiently localized no surgical procedure directed to evacuation or to excision or removal of the gangrenous tissue can be more dangerous than the condition left to itself. The surgeon may, therefore, be impelled to perform a pneumotomy or a pneumectomy.
When the lung tends to protrude or prolapse through an external injury the condition is referred to as pneumocele, or sometimes as hernia or prolapse of the lung. This is rare, and occurs usually in connection with punctures or stab wounds placed anteriorly and generally low. The lung may be entangled, after having been forced out by violent coughing, and the external portion has been known to be strangulated in such a way as to slough off. Should this occur the mass may be permitted to slough, or it may be removed by cautery or by ligature, the wound being left to heal by granulation. In rare instances the pneumocele has been covered by the parietal pleura, as is abdominal hernia by parietal peritoneum.