LUNG, in anatomy, the name of each of the pair of organs of respiration in man and other air-breathing animals, the corresponding organs in fishes being the branchiae or gills (see Respiratory System). The word in Old English was lungen; it appears in many Teutonic languages, cf. Ger. Lunge, Du. long, Swed. lunga; the Teutonic root from which these are derived meant “light,” and the lungs were so-called from their lightness. The word “lights” was formerly used as synonymous with “lungs,” but is now confined to the lungs of sheep, pigs or cattle; it is etymologically connected with “lung,” the pre-Teutonic root being seen in Sansk. laghu, Gr. ἐλαφρός.
Surgery of the Lung and Pleura.—When a person meets with a severe injury to the chest, as from a wheel passing over him, the ribs may be broken and driven into the lung. Air then entering into the pleural space, the lung collapses, and breathing becomes so difficult that death may ensue from asphyxia. Short of this, however, there is a cough with the spitting of frothy, blood-stained mucus or of bright red blood. All that can be done is to place the person on his back, slightly propped up by pillows, and to combat syncope by subcutaneous injections of ether and strychnia.
Empyema means the presence of an abscess between the lung and the chest wall, i.e. in the pleural space; it is the result of a septic inflammation of the pleura by the micro-organisms of pneumonia or of typhoid fever, or by some other germs. As the abscess increases in size, the lung is pushed towards the spine, and that side of the chest gives a dull note on percussion. If much fluid collects the heart may be pushed out of its place, and, the lung-space being taken up, respiration is embarrassed. Having made sure of the presence of an abscess by exploring with syringe and hollow needle, the surgeon opens and drains it. The drainage is made more effectual by removing an inch or so of one of the ribs, for, unless this is done, there is a risk of the rubber drainage tube being compressed as the ribs come closer together again.
The lung itself has sometimes to be operated on, as when it is the seat of an hydatid cyst, or when it contains an abscess cavity which cannot otherwise be drained, or when it becomes necessary to remove a foreign body the exact situation of which has been revealed by the X-rays. Portions of some of the ribs having been resected, the pleural cavity is opened, and if the lung has not already become glued to the chest-wall by inflammatory adhesions, it is stitched up to the chest-wall, and in a few days, when adhesions have taken place, an incision is safely made into the lung-tissue. See also Respiratory System. (E. O.*)