Rectal prolapse

Occasionally, the rectum prolapses out of the anus. It may prolapse incompletely, so that only a pink fold of mucosa shows, or it may prolapse completely, so that the whole thickness of the rectal wall is turned inside out (procidentia), and may ulcerate. At the same time the patient's anal sphincter may stretch and become patulous, so that he is incontinent. At first his rectum only prolapses with defaecation, later it does so on minimal coughing and straining; finally it is outside all the time.

Although the rectum can prolapse at any age, it commonly does so in children between the ages of 3 and 5 (usually incompletely), and occasionally does so in the aged (usually completely). The reasons are not clear. Prolapse is more common in malnourished children, perhaps because of poor tone and wasting of the anal sphincter mechanism. Prolapse is also associated with diarrhoea. If a child's malnutrition is treated, his prolapse is usually cured also. A chronic cough, especially whooping cough, and worms, particularly Trichuris, may also play a part.

A child's rectal prolapse usually presents as his mother noticing that ''Something red appears at his anus after defaecation''. When she brings him to you, there is usually nothing to see. If there is, you can usually replace his rectum manually, but it is likely to return. If it remains prolapsed too long, it ulcerates. His prolapse will however correct itself as he grow older and his nutrition improves; some surgeons accept this, and don't usually do anything further. You can strap his buttocks as described below. If this does not prevent it recurring, you can usually cure him quite easily with Thiersch's operation. Pass a suture around his anus subcutaneously, tie it just tight enough to prevent his rectum prolapsing, and just loose enough to let him pass his stools. If you insert a non- absorbable suture, you will have to remove it later. Some surgeons also use gallows traction.

An adult's rectal prolapse is much more difficult to treat. Symptoms are due to the prolapse itself, and to a particular type of incontinence caused by difficulty in regulating bowel action. If you cannot refer him, Thiersch's operation, preferably using wire, quite often succeeds. If it does not, you can hitch his rectum to his sacrum, in an operation which is similar to the ventrisuspension of a prolapsed uterus (20.10), but is more difficult.

RECTAL PROLAPSE EXAMINATION. If a patient's prolapse is intermittent, he will give a history of ''something coming down'', but there will be nothing to see. If he is an adult, pass a proctoscope and ask him to strain down. His anal mucosa will prolapse into the hollow of the proctoscope, and extend beyond his anus as you withdraw it. If his prolapse is complete, the whole thickness of his rectum slides out all round, sometimes for several centimetres. When you do a rectal examination, his anal sphincter feels weak.

To find out if his prolapse is partial or complete, put you finger into his rectum, and feel the protruding ring of mucosa between your finger and thumb. If all you can feel is two layers of mucosa, it is incomplete; if you can feel more tissue than merely mucosa, it is complete.

If he is a child, distinguish a prolapse from a rectal polyp, or an intussusception. Examine him immediately after defaecation. Feel the outer aspect of the swelling, up to his anal orifice. In a prolape you cannot enter his anal canal at any point, but you can pass your finger between an intussusception, or a rectal polyp, and his anal wall.

If he is an adult, you will probably find that his prolapse is reduced when you examine him. Ask him to bear down to let you observe it. His anus may be large, and his sphincters abnormally lax. Assess their tone, because this is an important determinant of treatment and prognosis. Put your finger into his anus, and ask him to try to squeeze it. You may feel very little contraction. If it is very lax, he may allow you to put three or four fingers into it without discomfort.

CHILDREN [s7]WITH RECTAL PROLAPSE If a child has diarrhoea, treat it. If his nutrition is poor, treat that first. These are the common causes of prolapse, and treatng them usually cures him and avoids an operation.

MANUAL REPLACEMENT AND STRAPPING. Using a glove and KY jelly, replace his prolapse manually. You may have to squeeze it for 15 minutes to do so.

Strap his buttocks securely together with a large gauze pad up against his anus. If this method is to work, the strapping must be adequate, painless, and easily applied. Apply a large square to each buttock. Join these with a 2.5 cm transverse strip, so as to close his buttocks, and leave this strip on during defaecation. Afterwards, remove it, clean his buttocks, and replace it with a fresh strip. Ask his parents to repeat this after each bowel movement, and give them some vaseline gauze, plain gauze, and strapping, with which to do it. After a time, his rectum will stay up where it belongs. Strapping is often all that is necessary.

If, after three or four reductions his prolapse soon recurs after defaecation, leave it out. Try again 3 or 4 days later, when it may stay in. After a week or two it will probably stay in. If it is not controlled after several weeks, and he is fit enough, do a temporary Thiersch's operation using No. 2 chromic catgut. If he is not fit enough, wait longer. Alternatively, consider gallows traction.

CAUTION ! Too much trauma reducing a prolapse causes bleeding, which can be worse than leaving it outside covered by vaseline gauze.

GALLOWS TRACTION is controversial. Some surgeons don't use strapping and proceed immediately to gallows traction. Others consider it ineffective and messy. If you decide to use it, suspend him in the gallows position for a few days to two weeks (78.2). If this fails, consider a temporary Thiersch's operation.

ADULTS [s7]WITH RECTAL PROLAPSE If an adult has an incomplete prolapse and the tone of his sphincter is normal, or only slightly relaxed, you can treat him in much the same was as if he had large third degree piles (22.6). Insert a bivalve proctoscope, and use haemostats to catch catch his redundant mucosa at the 3, 7, and 11 o'clock positions. Use scissors to divide the prolapse into three main portions, like primary piles, with narrow bridges of skin and mucosa between them. Tie and excise the bunches of mucosa, as if they were piles. These ''piles' are broad-based, so apply a transfixion ligature before you excise them. Preserving satisfactory mucocutaneous bridges may be difficult, but if one or even two are cut, the result may still be satisfactory.

If he has an incomplete prolapse and his sphincter is grossly relaxed, treatment is difficult, so refer him. If you cannot refer him, he may possibly benefit from Thiersch's operation (see below).

If he has a complete prolapse, refer him. If you cannot refer him: (1) If his prolapse is [lt]15 cm and his sphincters are not too lax, try Thiersch's operation. (2) Otherwise, and if Thiersch's operation fails, try the operation described below for hitching up his rectum to his sacrum. If you can do a hysterectomy, you can do this, but it is not always successful.

Fig. 22-13 THIERSCH'S PROCEDURE. A, the child's prolapsed anus. B, make two cuts in his skin 2 cm from his anus. C, pass the suture material from 12 to 6 o'clock on the right hand side. D, now pass it round on the other side. E, tighten the suture material with your assistant's little finger in the child's anus. F, finally bury the sutures. From Goligher JC, ''Surgery of the Anus, Rectum and Colon', (4th edn 1980), Fig. 187 Bailli[gr]ere Tindall, with kind permission.

THIERSCH'S OPERATION [s7]FOR RECTAL PROLAPSE INDICATIONS. (1) Children in whom strapping and/or gallows traction have failed. (2) Elderly debilitated adults whose life has been made miserable by rectal prolapse, particularly if you are inexperienced in abdominal surgery.

ANAESTHESIA. (1) Ketamine for children (A 8.2). (2) General anaesthesia.

SURGERY. Put the patient into the lithotomy position and replace his prolapsed rectum (A, in Fig. 22-13). Put your finger in his anus and feel his sphincter. It may be so loose that you can hardly feel it. Prepare and drape him.

Make short incisions in the 6 o'clock and 12 o'clock positions 2 cm from his anus (B). Then, take a large curved round-bodied needle and thread it. For an adult use fine braided stainless 1 mm steel wire, or ''2' braided silk. For a child use ''1' or ''2' chromic catgut.

Put the needle into his skin in the 12 o'clock position 1 cm from his anus. Pass it subcutaneously round his anus 1 cm from it and out again at the 6 o'clock position (C). Pull the suture material through.

Put the needle back into the 6 o'clock hole from which it has just come. This time pass it round the other side of his anus and out at the 12 o'clock incision (D). Ask your assistant to put his little finger into the child's anus (E) (in an adult he should use his index). Tie the suture round his finger. Secure it with several knots, cut the ends 1 cm long and bury them. Close the two skin wounds with catgut.

CAUTION ! (1) You must be able to get the tip of your little finger into a child's anus and your whole finger into an adult's anus. Getting the tension of the suture material right is difficult. If it is too tight, it will interfere with defaecation, and cause faecal impaction, or the wire may cut out. If it is too loose, it will not cure his prolapse. (2) Don't forget to make sure that he can pass stools normally before discharge.

The major complications are breakage of the suture, and difficulty in passing even a soft stool, if the suture is too tight. Advise an adult to eat his traditional high-fibre diet.

Alternatively pass an ordinary tubular hypodermic needle round his anus from the 12 o'clock to the 6 o'clock positions, and vice versa. Pass the suture material through this, and tie it as above.

POSTOPERATIVELY, an adult is usually old, so leave his non-absorbable suture in.

STITCHING THE RECTUM TO THE SACRUM Expose the patient's pelvis through a lower midline incision, and pack away his gut. Mobilize his rectum down to his pelvic floor, laterally by incising his peritoneum, and posteriorly by finger dissection, keeping close to his rectal wall. If you don't there will be massive bleeding. Dissection is quite easy, because there is a bloodless plane between the rectum and the sacral fascia. Be careful not to go too far backwards, because there is a plexus of veins just anterior to the sacrum; if you damage this he may bleed severely. Bleeding gets worse with each attempt at ligation.

If you are unlucky and do injure this venous plexus, insert a gauze pack and wait 10 minutes. If bleeding continues, pack the area with ribbon gauze, leave the pack in place, and remove it under general anaesthesia after 48 hours. The prolapse may even be cured.

Divide the lateral ligaments (the sacrouterine ligaments in a woman, 20-17). These contain a few blood vessels, which may need transfixing.

Using non-absorbable ''0' or ''1' multifilament sutures, pull his rectum firmly upwards towards his sacral promontary, and place about 6 sutures between his pre-sacral fascia and the tissues around the back and sides of his rectum.

If you have an ''Ivalon sponge' or ''Marlex mesh', insert a broad strip of this between his rectum and his sacral periosteum.

CAUTION ! (1) Don't penetrate the wall of his rectum. (2) Be sure to put all the sutures in first and then tie them later. (3) Make sure his rectum is pulled up well out of the hollow of his sacrum.