348 ' LUNGS AND PLEURA. 



apt to suffer from pneumonia produced by foreign bodies. The lung may 

 be penetrated either by some sharp object making its way forwards from 

 the rumen or recticulum or by liquid or solid material passing into the 

 trachea. . These are two common methods by which this form of pneu- 

 monia is produced. 



PNEUMONIA DUE TO THE MIGRATION OF FOREIGN BODIES FROM 

 THE RETICULUM. 



Causation. The conditions under which food is swallowed by rumi- 

 nants after preliminary mastication permit indigestible objects, such as 

 stones, fragments of wood, nails, needles, bits of iron wire, etc., to enter 

 the rumen, whence they reach the reticulum in consequence of peristaltic 

 movements. Sharp, perforating objects, like needles or fragments of iron 

 wire, penetrate the walls of the gastric compartments, and, impelled by 

 the movements of these organs, pass through the intervening tissues, 

 usually in the direction of the heart. Under conditions which cannot 

 precisely be defined, these foreign bodies make their way tow^ards the 

 pleural cavity (usually the right, in consequence of the situation of the 

 reticulum), traverse the diaphragm, and directly penetrate the base of 

 the lung. 



As the migrating object is usually infected, its passage through the 

 diaphragm always produces a localised patch of diaphragmatic pleurisy. 

 Although possible, it is only rarely that the pleural sac becomes generally 

 infected, or that rapidly fatal septic pleurisy is set up. Usually the 

 localised pleurisy causes the base of the lung to become adherent to 

 the anterior surface of the diaphragm. The foreign body continuing 

 its movements, passes into the lung, and there sets up pneumonia. 



Symptoms. When the practitioner is first consulted he often finds 

 only indications of the crisis period of a localised pneumonia at the base 

 of the affected lung. The symptoms include fever, accelerated breathing, 

 moaning, loss of appetite, cough without discharge, dulness over the base 

 of the lung on percussion, disappearance of the respiratory murmur in 

 the dull area, souffle opposite the inferior bronchi, and normal or juvenile 

 respiration towards the front, i.e., in the anterior lobe, and sometimes 

 in the cardiac lobe. 



The temptation under such circumstances is to deliver a diagnosis 

 of simple pneumonia with prognosis of probable recovery. It should be 

 remembered, however, that in all cases of basilar pneumonia without 

 affection of the anterior lobes there is a considerable chance of the con- 

 dition being due to the presence of a foreign body. On more careful 

 examination it is found that the intercostal spaces opposite the affected 

 region are very sensitive, and that the circle of the hypochondrium is 



