The operation may be performed with a simple trocar and canula, round, about an eighth of an inch in diameter, and at least two inches in length. The point must be sharp, and it must be pushed in with considerable quickness, so as to penetrate, not merely push forwards, the pleura, which may be tough, and thicker than usual. Once the skin is pierced, the instrument must be directed obliquely upwards, so as to make the opening and position of the trocar dependent. When the trocar is withdrawn the fluid may be allowed to flow so long as it keeps in a full equable stream; whenever it becomes jerky and spasmodic, the canula should be removed before the sucking noise of air entering the chest is heard.
In more chronic cases, where the quantity of fluid is large, and especially if it is thick and curdy, the exhausting syringe of Mr. Bowditch is an improvement on the simple trocar and canula.
It consists of a powerful syringe, which fits accurately to the trocar with which the puncture is made. There is a stop-cock between the trocar and syringe, and another at right angles to the syringe. The trocar being introduced, it is held firmly in position by an assistant, by means of a strong cross handle; the first stop-cock is then opened, and the syringe worked slowly till it is filled with fluid through the trocar, the other delivery stop-cock being closed. The first is then closed, and the second opened; the syringe is then emptied through the second into a basin. By a repetition of this process, the fluid can be removed at pleasure, without any risk of the entrance of air.
Dieulafoy's aspirateur, which the author has now used in a very large number of cases, will be found the best method yet devised of safely removing the fluid in cases of serous effusion. But in severe cases of empyema the pus is sure to be reproduced in the great majority, and then a free incision, with strict antiseptic precautions, will be needed, and subsequent free drainage.
The author has used with great benefit silver tubes, like long narrow trachea-tubes, with broad shields, to insure free drain.
CHAPTER XI.
OPERATIONS ON ABDOMEN.
Paracentesis Abdominis.—To withdraw fluid from the abdominal cavity is an exceedingly simple operation in itself, though certain precautions are necessary to render it safe.