Pelvic abscesses

Pus in the pelvis is nearly as dangerous and difficult to manage as pus under the diaphragm. You will see several kinds of pelvic abscess which need managing in different ways:

(1) Following infection of the female genital tract which can be any of the varieties of pelvic inflammatory disease (PID) described in the next section. Those following a septic abortion or puerperal sepsis may be caused by anaerobes, and so are particularly serious and likely to spread. The patient may be very ill; you may have difficulty finding pus, and knowing when and how to drain it. The danger is that pus may build up as a mass above her pelvis, and spread upwards into her peritoneal cavity, perhaps fatally, instead of discharging spontaneously and harmlessly into her rectum. Drain this type of pelvic abscess early, as soon as pus has formed, and don't ''sit on it'.

(2) Following appendicitis. You can treat pelvic abscesses of this type non-operatively with much more safety, as in Section 12.2.

(3) Following generalized peritonitis, such as that caused by a perforated peptic (11.2), or a typhoid ulcer (31.8). If a patient makes good progress from the disease which caused his abscess, the pus in his pelvis is unlikely to kill him.

A pelvic abscess can grow quite large without making a patient very ill, or causing very obvious signs, so that, unless you do frequent rectal or vaginal examinations, you can easily miss one. You will need experience and a sensitive finger. One danger is that a pelvic abscess may obstruct the gut (10.13). Drain a man's abscess rectally, and, if possible, a woman's vaginally. This is easier then doing a laparotomy. If coils of gut lie between the pus and her posterior fornix, it will be more difficult to diagnose, and you will have to drain it suprapubically. Sometimes, an abscess drains into the rectum spontaneously, but incising it speeds recovery.

Fig. 6-7 DRAINING PELVIC PUS. A, if you drain pus vaginally, do so with particular care, or you may penetrate coils of gut. B, occasionally, pus presents above the inguinal ligament and has to be drained like this.

PELVIC ABSCESSES This follows from Section 6.3 on abdominal abscesses.

DIAGNOSIS. PID is the commonest cause. Watch also for the formation of a pelvic abscess when a patient is recovering from appendicitis (12.1), peritonitis, or an infected Caesarean section (6.8); watch for fever and the passage of frequent stools (''diarrhoea'), with tenesmus and mucus. Feel for: (1) A boggy, tender mass above a man's prostate filling his rectovesical pouch, or a soft bulging swelling in a woman's pouch of Douglas. Sometimes, the mass is almost visible at her vulva. You will not find fluctuation. (2) Tenderness and occasionally an ill-defined mass suprapubically. If you suspect a pelvic abscess in a woman, put one finger into her rectum and another into her vagina. Normally, they should almost touch. If she has an abscess, you will feel it between your fingers.

You can confuse a pelvic abscess bulging into the pouch of Douglas with: (1) A chronic ectopic pregnancy (haematocoele, 16.7). (2) An ovarian cyst (20.7). Some suspected cysts turn out to be post inflammatory collections of fluid (post-inflammatory pelvic pseudocysts).

If there are no signs that the infection is spreading upwards into the peritoneal cavity, operation is not urgent. Give antibiotics as for peritonitis (2.9, 6.2). Carefully monitor the patient's temperature and the mass, and drain the abscess as soon as it is ripe. If you doubt whether it is ''ripe' for drainage or not, wait.

CAUTION ! An abscess which is enlarging suprapubically needs draining urgently.

VAGINAL DRAINAGE [s7]OF A PELVIC ABSCESS (posterior colpotomy) INDICATIONS. A pelvic abscess which extends into the pouch of Douglas.

ANAESTHESIA. (1) General anaesthesia. (2) Ketamine (A 8.1).

PREPARATION. Put her into the lithotomy position and catheterize her bladder. Do a vaginal examination to confirm the diagnosis.

INCISION. Expose the vaginal wall of her posterior fornix (which should be bulging) with a short broad speculum. Ask an assistant to depress her vaginal wall with a Sims speculum, while you raise the posterior lip of her cervix with a vulsellum. Push a large needle into the swelling in the midline and aspirate:

If you aspirate pus, this confirms a pelvic abscess, so proceed as below.

If you aspirate aspirate a pale yellow fluid, you are probably draining a post-inflammatory pseudocyst, so also proceed as below.

If you aspirate blood, either you have punctured a blood vessel (which should not happen if the needle is in the midline; the blood will clot), or she has a haematocoele due to a chronic ectopic pregnancy (if so the blood will not clot), for which you must do a laparotomy (16.7).

If you find an abscess or a post-inflammatory cyst, make a 2[nd]3 cm transverse incision in her vaginal wall in the place where you found pus. Push in a haemostat; pus or fluid should flow. Open the forceps and pull them back to enlarge the opening. Explore the abscess with your finger; feel for loculations in the abscess cavity and gently open them. Insert a large drain and suture it to her perineum or labia. Leave it in for a few days and continue antibiotics. Pus may discharge for up to 2 weeks.

CAUTION ! (1) If pus is pointing laterally, drain it as close to the midline as you can, to avoid injuring her ureters (20-9). (2) Don't push too deeply into the abscess with the haemostat, or its roof may give way and spread the pus into her peritoneal cavity; or you may damage a loop of gut. Be safe, and gently insert your finger through an adequate incision. (2) The effect should be spectacular, and she should improve markedly in a few days. If she does not improve, she has more pus somewhere, and probably needs a laparotomy.

RECTAL DRAINAGE [s7]OF A PELVIC ABSCESS Take the patient to the theatre and anaesthetize him. Put him into the lithotomy position. While his abdomen is relaxed, palpate it gently. Then examine him bimanually with one finger in his rectum, and your other hand on his abdomen. If you can ballot the mass, needling is unnecessary [md]drain it immediately.

To needle it, take a three-ringed 10 ml syringe, as used for injecting piles, and fix a 1 mm needle to it. Place the tip of your gloved right index finger over the place in the anterior wall of his rectum where you feel pus. Slide the point of the needle up alongside your finger, then push it through the wall of his rectum for about 2 cm. Aspirate. If no pus comes, inject a few ml of saline, and aspirate again. The needle may be blocked.

If you aspirate pus, or are sure that his abscess is ripe, drain it. Either push the tip of your index finger into it[md]pus will burst out. Or take a long curved haemostat, and with your index finger again acting as a guide, push its tip through the anterior wall of his rectum into the abscess. Enlarge the hole by opening and closing the jaws a few times.

CAUTION ! (1) Opening an abscess before it is properly formed is useless and dangerous. (2) Don't use any sharp instrument to penetrate the rectal wall, it may bleed seriously.

SUPRAPUBIC DRAINAGE [s7]OF A PELVIC ABSCESS This is sometimes needed in women (it is almost never necessary in men), particularly after an abortion or a Caesarean section when you can feel a mass suprapubically but not vaginally. Fortunately, you can usually drain an abscess from below, which is easier and safer. Rarely, if more pus collects after vaginal drainage, you may need to drain it suprapubically.

If she is distended and tender, and there is induration behind and above her pubis, especially if she is also severely toxaemic, drain the pus suprapubically.

Catheterize her bladder to make sure it is empty. Make a 10 cm midline incision immediately above her pubis. Incise her linea alba and her peritoneum. If you enter her general abdominal cavity (which you can usually avoid doing), inspect it first, then pack off her upper abdomen with some large moist abdominal packs. Gently feel for the abscess. Look for pus, for loops of gut stuck down in her pelvis, and for oedematous or congested tissues. Insert a self-retaining retractor. Use a ''swab on a stick' to gently mobilize adherent loops of gut, until you have found the pus.

CAUTION ! (1) Don't lower her head to improve exposure; this may spread the infection. (2) Keep manipulation to a minimum. (3) When you have found pus, do nothing more than is necessary to ensure adequate drainage. Don't break down the outer walls of the abscess cavity, but do break down any loculi. Distinguishing between them may be difficult.

Culture the pus and insert a drain. Remove all the packs; suture her abdominal muscles securely, but do not close her skin immediately (9.8).

DIFFICULTIES [s7]WITH PELVIC ABSCESSES If a patient has COLICKY PAIN, VOMITING, AND ABDOMINAL DISTENSION, his small or his large gut is obstructed. Try to treat him non-operatively, with nasogastric suction and intravenous fluids (9.9, 10.13, A 15.5). Draining his abscess will usually cure the obstruction. If it does not, you may have to relieve it operatively (10.12).

Fig. 6-8 CAUTION! PID AND HIV. The organisms responsible for PID may be: 1, sexually transmitted (gonococci, mycoplasma, or chlamydia). 2, The normal flora of the patient's gut and vagina (coliforms, anaerobes, and, rarely, actinomyces). Both partners are potentially in danger of HIV, see Chapter 28a. With the kind permission of the Daily Telegraph.