Volvulus of the small gut

In the industrial world volvulus of the small gut is rare, except in babies and small children, but in much of the developing world it is seen at all ages, particularly in young men. The small gut rotates on its mesentery, or on a band 5[nd]10 cm from the ileo-caecal valve, which tethers it to the posterior abdominal wall. As it rotates it traps large volumes of blood and fluid. Most of the small gut may rotate, apart from its top and bottom ends, or only a smaller part. Sometimes, an adhesion to a loop of small gut starts the twist, or the patient may have a primary sigmoid volvulus, and loops of his small gut may twist around this (10-17).

Volvulus of the small gut is a sudden deadly illness in which the symptoms of acute obstruction rapidly become those of strangulation. As his mesenteric vessels occlude, and his gut strangulates, he has a sudden severe diffuse abdominal pain and vomits copiously. A typical history is of sudden abdominal colic, distension and vomiting, coming on after a large evening meal. Early on, he looks ill and has a fast pulse and a low blood pressure[md]his abdomen may be fairly relaxed and not particularly tender at this stage. You may feel an ill-defined mass, but high pitched bowel sounds and a few loops with a fluid level may be the only signs of a dangerous volvulus. A notable feature is the speed with which his abdomen distends. He is in severe pain, and is always shocked. Later, his abdominal muscles become rigid. If his strangulation is not relieved, his gut eventually becomes gangrenous. You will also see: (1) Mild cases with a typical history, but no signs other than mild abdominal distension, who recover spontaneously. (2) Cases which progress slowly and which are difficult to distinguish from other forms of ileal obstruction.

In theory, treatment is easy[md]untwist his gut. One of your difficulties will be to make the diagnosis, when all you see at laparotomy are distended loops of small gut. Manipulating them is dangerous, whether or not they are strangulated. If a loop ruptures, he will be lucky to survive the flooding of his abdomen that results. He has about a 30% chance of death, but if he lives his volvulus will not recur.

Fig. 10-13 VOLVULUS OF THE SMALL GUT is a sudden deadly illness in which the symptoms of obstruction progress rapidly to those of strangulation. Kindly contributed by Gerald Hankins.

VOLVULUS OF THE SMALL GUT For the general method for gut obstruction see Sections 10.1 and 10.3. Resuscitate the patient vigorously.

X-RAYS show distended small gut, sometimes with a regular horizontal step-ladder pattern, and many fluid levels in the erect film.

CAUTION ! When a strangulated closed loop is distended with blood, there may be no fluid levels, so that the X-rays look normal.

INCISION. Make a midline or a right paramedian incision. You will find purple, congested, haemorrhagic, distended small gut full of food and fluid. A collapsed caecum shows that the obstruction is in his small gut.

Try to reach the base of his mesentery. Approach this by first putting your hand down into his pelvis, and then up along the posterior border of his abdominal wall. Usually, the whole of his small gut is twisted, except the first few centimetres of his jejunum and his terminal ileum. Rotate the whole mass until his volvulus is undone. If you find a band near his ileo-caecal valve, dividing it may help you to reduce the volvulus.

Deliver his gut, untwist it, pack it with moist towels, and decompress it. Do this before you assess its viability. Push fluid proximally (10-9), or distally into his caecum through his ileo-caecal valve. This will probably be more satisfactory than doing an enterotomy and using Savage's decompressor. If you decide to use one, do so through an incision in healthy gut distal to the point of torsion.

If you have difficulty untwisting his gut before you decompress it, decompress it first. Introduce the decompressor into a distended loop through a single or double purse string suture, and decompress it proximally and distally.

If his gut is viable (usual), leave it. If it is not viable, resect and anastomose it (9.3). If you are not sure if his gut is viable or not, assess it as in Fig. 9-8. Wait for at least 10 minutes before you decide that it is gangrenous.

If the gangrenous section ends above his ileo-caecal valve, resect it and do an end-to-end anastomosis

If his gut is gangrenous down to his caecum (unusual), do an ileo[nd]colic anastomosis.

CAUTION ! Be sure to select healthy gut for the anastomosis, with obviously visible pulsations in the vessels that supply it[md]a serious and sometimes fatal complication is a fistula due to necrosis of the gut at the site of the anastomosis.

Continue nasogastric suction and intravenous fluids postoperatively. He may need blood.