SMALL BOWEL OBSTRUCTIONOutline the clinical presentation, causes and management of small bowel obstruction.

Clinical presentation:

The presenting symptoms are colicky abdominal pain, vomiting, absolute constipation and abdominal distension. The cause may be

1. In the lumen-tumour(e.g. leiomyoma), food bolus, gallstone.

2. In the wall-crohn's disease, radiation stricture

3. Outside the lumen-adhesions, volvulus, hernia, intussusception.

Common causes of small intestinal obstruction are irreducible hernias and adhesions.

Management:

The diagnosis is made from the history and clinical examination, which includes making a note of:

1. Hydration

2. Pulse

3. Blood pressure

4. Temperature

5. Mucous membranes

6. Abdominal scars

7. Hernia orifices

8. Distension

9. Presence of high-pitched bowel sounds

Any sign of tenderness or peritonism imply that the bowel may become ischaemic.

Investigations should include:

1. Full blood count-may demonstrate an elevated white count.

2. Renal function

3. Abdominal radiograph-may show small bowel dilatation, and air fluid levels.Treatment is by resuscitation with intravenous fluids, and monitoring of the pulse, blood pressure and urine output. A nasogastric tube is passed to prevent vomiting and decompress the bowel.

Urgent surgical intervention is required if the patient has a tender irreducible hernia or any signs of peritonism.

If the patient has had a previous operation adhesions are the likely cause and the patient is initially treated conservatively for 24hrs if they have no signs of peritonism. If the condition fails to resolve, a laparotomy is required.