Obstruction by bands and adhesions

Bands and adhesions sometimes form outside a patient's gut and obstruct it. They are the result of some focus of infection being slowly converted into fibrous tissue, and can follow: (1) A previous abdominal operation, which may be followed by obstruction soon afterwards, as in Section 10.13, or later, as described below. You can reduce the probability of this happening by pulling his omentum down over his gut, and particularly the site of an anastomosis, before you close his abdomen after a laparotomy. This will reduce the chances of his gut sticking to his abdominal wall. (2) Abdominal sepsis of any kind, such as local or general peritonitis, an appendix abscess, a perforated peptic ulcer and especially PID (6.6). In communities where there is much PID, obstruction due to adhesions is common, and is apt to recur, so that a woman who has had one attack is likely to have another. (3) A congenital anomaly[md]congenital bands are unusual.

If a loop of gut has stuck to the parietal peritoneum at the site of an old scar, you can usually free it without too much difficulty, but even this can be dangerous because you can easily damage it. If PID has caused massive adhesions that have stuck loops of her gut firmly into her pelvis, releasing them may be very difficult. As you will soon learn, freeing them is an art.

Obstruction due to adhesions is less likely to strangulate than some other kinds of obstruction, and is more likely to be subacute, self-limiting, and recurrent, so you may be able to treat it non-operatively[md]if you are sure of the diagnosis!

Fig. 10-11 SEPARATING ADHESIONS. The great danger is that you may perforate the patient's gut: A, on entering his abdomen. B, on cutting adhesions between two loops of gut. C, when freeing adhesions between his gut and his abdominal wall, or (not shown) when closing his abdomen in the presence of obstructed gut. D, the safest way to separate adhesions is to use the ''push and spread technique' (4-8; preferably use Metzenbaum's or McIndoe's scissors, which are not so blunt as those shown here).

BANDS AND ADHESIONS [s8]OBSTRUCTING THE GUT For the general method for gut obstruction see Sections 10.1. and 10.3. For non-operative treatment, see Section 10.5. See also PID in Section 6.6.

INCISION. Open the patient's abdomen with great care. Always dissect under direct vision: so get good exposure, and keep the field dry. Don't use diathermy close to the gut wall: it too easily causes necrosis.

If he has had a previous paramedian incision, reopen his abdomen through it, unless this is difficult. Start above or below it in an area which is free of adhesions. Put a finger into the incision and explore the deep surface of the old scar. Work slowly with a sharp scalpel and detach the adherent gut from under it.

If he had a transverse or oblique incision previously, make a median or paramedian one now.

If he had a vertical midline incision, reopen that instead of making a parallel paramedian incision, because the intervening skin may necrose. Start in normal skin at one end where, hopefully, there will be no adhesions.

If you have to enter his abdomen through the site of multiple adhesions, dissect them away with the utmost care and patience.

If his gut has completely stuck to his abdominal wall, be prepared to excise a piece of the adherent peritoneum when necessary, rather than damage his gut.

FREEING THE ADHESIONS. Look for the site of the obstruction, which may be a band with a knuckle or loop of gut caught under it. This has a 95% chance of being in his small gut and a 75% chance of being in his ileum. Use the ''push and spread technique' with blunt tipped Metzenbaum's or McIndoe's scissors (D, 10-11 and B, 4-8). Use the outer sides of the blades to spread the tissues. If you work carefully, you can define tissues when they are matted together, by opening up tissue planes, and without injuring anything. You will see what is gut, and what is an adhesion, and will be able to cut in greater safety. Work away at one site and then at another until the adherent loops unravel.

Alternatively, use the ''pinching technique'. Pinch your index finger and thumb together between two loops of adherent gut.

Gentle traction will help you to dissect the loops of his gut free from one another. Grip them firmly with moist gauze, and release it periodically, to help you to identify what you are cutting, and to control bleeding.

When you have divided a band, you will want to know if the trapped gut is viable or not[md]do this using the criteria in Section 9.3 and Fig. 9-8.

If you can squeeze gut contents past a kink in the gut, you can probably leave it safely. Don't try to cut every adhesion you see. Freeing them can go on indefinitely, and can be dangerous. If there are adhesions between loops which are not causing obstruction, leave them.

CAUTION ! Work slowly and carefully. Making a hole in the gut wall increases greatly the postoperative morbidity, especially the risk of a fistula (9.14).

DIFFICULTIES [s7]WITH INTESTINAL ADHESIONS If BLEEDING OBSTRUCTS YOUR WORK, apply gentle pressure with a warm moist pack. Leave it alone for a few minutes, and dissect somewhere else.

If you STRIP UP THE SEROSA WITH SOME OF THE MUSCLE layer, leave it. But, if you open his gut, close it carefully in two layers. If the edges of the defect are ragged, trim them neatly, so that you only use full-thickness gut for closure[md]make sure that there is no obstruction distal to the point of repair! If there is, a fistula is sure to form.

If COILS OF GUT ARE FIRMLY STUCK down in the pelvis, try to carefully pinch them off the pelvic wall. If you fail, bypass them with an entero-enterostomy (29-8). This is a safe way out of a difficult problem, provided that a long length of small gut is not bypassed. Choose an easily accessible loop of gut proximal to the obstruction, and anastomose it side-to-side with a collapsed loop distally. Some of the absorptive surface of the patient's gut will be lost, but you will have saved her life (she is usually female). If necessary, another operation can be done later when she is in better condition. This is a common and difficult gynaecological problem.