DIAGNOSTIC SYMPTOMS OF THORACIC INJURIES. 
225 
cotton-wool plug. The emphysema in the neighbourhood of chest 
wounds is usually of little importance. 
(2) Hsemothorax, or the presence of blood in the pleural sac, arises 
either from rupture of vessels (intercostal) in the wall of the thorax, 
or from injury of the lung or heart. Large quantities of blood in the 
thorax may certainly produce sudden death by compressing the lungs 
and inducing suffocation; but even a small quantity is dangerous, 
because organisms may reach it either through the chest wall or lung, 
and produce septic pleurisy. The simultaneous existence of hsemothorax 
and pneumothorax accordingly render prognosis doubly grave. 
(8) Pleurisy results from the injury, and from the wound becoming 
infected. It may thus arise either from the external or the lung injury, 
and will evidently be favoured by foreign bodies remaining in the wound, 
and by difficulties in carrying out antisepsis. Pneumonia only results 
in cases where the lung is simultaneously injured, and occasionally 
happens in cases of complicated fracture of the ribs. Gadeac describes 
a case of pyothorax in the horse, which was treated by washing out the 
thorax. During the operation a glass tube about 4 inches in length and 
.JU inch in diameter slipped into the cavity. Seven ribs were resected, 
allowing the entire hand to be introduced and even the heait to be felt, 
near which the glass tube was found. It was removed and the wound 
healed. On subsequent post-mortem examination the affected half of 
the lung was found entirely adherent to the pleura costalis; the lung 
itself was healthy. 
Symptoms. In determining whether a penetrating wound of the chest 
exists, one must not immediately have recourse to probes, nor should 
one, under any circumstances, proceed to explore with uncleansed fingers. 
As perforation of the still uninjured pleura costalis may be pioduced 
with a probe, such examination may introduce infectious mateiials into 
the thoracic cavity where the wound has not been first carefully cleansed. 
The question must therefore be answered by first considering the other 
symptoms. One should make— 
* (1) An examination of the position and condition of the wound and of 
the body which has produced it, as well as the method of its pioduction. 
This may suffice to indicate whether the chest-wall has been 
penetrated. 
(2) The breathing must be watched. Dyspnoea may be the result of 
pneumothorax, hsemothorax, or pleurisy, and occasionally in slighter 
degree, of injury to the muscles of respiration. Septic pleuritis is 
associated with high fever. Percussion determines the existence both 
of pneumothorax and of hsemothorax, and allows of their being 
distinguished. 
(8) Blood-stained discharge from the nose or mouth generally points 
Q 
v.s. 
