ABDOMINAL DRAINAGE.--Drainage of the peritoneum is accomplished by means of the glass drainage-tube (Fig. 202), or by capillary drainage with gauze. The peritoneum may be drained through the abdominal incision or through the vagina. On account of the difficulty of keeping the vagina sterile, drainage through the abdominal incision is the safer method. Vaginal drainage is preferred when the operation is performed through the vagina and no abdominal incision is made, as in the operation of vaginal hysterectomy. [Illustration: FIG. 202.--Glass drainage-tube.] The glass drainage-tubes should be of various lengths--5 to 7 inches. The outer diameter should be about ⅜ or ½ inch. The lower portion of the tube is perforated with small holes over a distance of about 1½ inches. Around the upper part or neck of the tube, which protrudes from the abdomen, is placed a square of rubber dam, such as is used by dentists, about 8 by 8 inches in size. The tube passes through a hole in the center of the rubber. The tube and the rubber dam may be sterilized by boiling. The tube is usually placed in the lower angle of the abdominal incision, and the abdominal dressing is split so that it may be placed around the tube. The bandage is applied so that the four upper tails pass above the tube and the two lower tails pass below it. The opening of the tube and the rubber dam are outside of the bandage. When the dressing and bandage have been applied, the opening of the tube is plugged with sterile absorbent cotton, and a handful of cotton is placed in the dam, which is then folded over and pinned. A sterile towel is placed over the dam. Some operators insert a cord of cotton or a few narrow strips of gauze to the bottom of the tube, in order to maintain a continuous capillary drain. Cleansing or emptying the drainage-tube is a procedure which should be very carefully attended to. Strict asepsis should be observed in all the manipulations. For the first few hours the general peritoneum is exposed to danger of infection every time the tube is opened. After the first twenty-four hours, though the danger of general peritoneal infection is remote or absent, yet there is always danger of local infection of the tube-tract. Such local infection may result in a persistent sinus or other complication. A ligature near to or in contact with the tube may become infected, and the sinus will remain open until the ligature is discharged. The tube may be cleaned by any careful nurse. The bedclothes should be drawn down to the pubis and the clothing should be drawn up, so that the abdomen is exposed. Sterile towels should be placed about the rubber dam. The hands of the nurse should be sterilized. The dam should be opened, the cotton should be removed, and the orifice of the tube exposed. The tube should be emptied with the long-nozzled syringe (Fig. 203), or with some other easily sterilized apparatus by which the fluid may be withdrawn.