APRECIACIÓN DEL CONSULTOR

diverticular abscess, which points and ruptures into it, establishing a fistula. The most common is a colovesical fistula. These result in recurrent lower urinary tract

infections. Pneumaturia and faecaluria may occur. Colovaginal fistula is very debilitating and necessitates urgent correction. A paracolic abscess may rupture laterally through the parietes presenting as a left groin abscess (if on the right, consider an underlying appendicitis). If this discharges, a colocutaneous fistula arises.

Coloenteric fistulae may cause diarrhoea.

Investigation

Diverticula can be seen on flexible sigmoidoscopy and colonoscopy. These examinations should not be carried out if acutely inflamed distal colon is suspected as perforation of the bowel may result. A CT scan will demonstrate diverticulosis and any associated acute

complication. Diverticular disease is best diagnosed by barium enema 6 weeks following the resolution of symptoms.

Treatment

Acute diverticulitis or a diverticular mass requires a broad-spectrum cephalosporin combined with metronidazole. Should symptoms or a mass persist it is worth continuing metronidazole for some weeks. During resolution of the acute phase the patient is allowed a soft diet. A high-fibre diet is instigated when the inflammation has settled. If simple dietary measures do not prevent constipation, additional fibre supplements may be prescribed. Antispasmodics may relieve cramping pains, but may slow colonic transit time, and should be avoided.

Surgery

Diverticulitis is a common cause of an acute abdomen. If there is peritonitis, a laparotomy must be performed. The usual operation is a Hartmann’s procedure, involving excision of the affected colon (usually the sigmoid), and fashioning of a left iliac fossa end colostomy. The distal end is either oversewn and fixed to the side of the pelvis, or brought to the abdominal skin as a mucous fistula, considerably facilitating the reversal of the end colostomy at a later date. This operation is applied to most acute conditions of the left colon presenting with either peritonitis or obstruction. It has been shown that excision of diseased sigmoid carries a better prognosis, compared with drainage and proximal loop colostomy, and left colonic anastomoses have high leak rates if performed in obstructed bowel or if there is peritonitis. Whilst Hartmann’s procedure certainly retains an important role in emergency surgery, sigmoid resection with a primary colonic anastomosis can be safely performed following peroperative (on table) colonic lavage in experienced hands.

Elective resection may be performed for chronic symptoms resulting from diverticulosis, usually pain or recurrent bleeding. A sigmoid colectomy with primary anastomosis is usually sufficient.

Further reading

Elliott TB, Yego S. Five-year audit of the acute complications of diverticular disease. British

Journal of Surgery, 1997; 84:535–539.

Golligher J. Diverticulosis and diverticulitis of the colon. In: Surgery of the Anus, Rectum and

Colon, 5th Edn. London: Baillière Tindall, 1984.

Morgan PG, Hyland JMP. Management of diverticular disease. Current Practice in Surgery, 1994;

6: 102–107.

Rotherberger DA, Wiltz O. Surgery for complicated diverticulitis. Surgical Clinics of North

America, 1993; 73:975–992.

Schoetz DJ. Changing concepts in diverticular disease. Diseases of the Colon and Rectum, 1983;

26:12–18.

Related topics of interest

Intestinal obstruction (p. 190); Lower gastrointestinal haemorrhage (p. 207).

ENDOSCOPY

Nick Lagattolla

Endoscopy is the visualization of the luminal surface of hollow viscera. A large number of organs can be inspected. The need for exploratory operations has thus diminished and diagnostic potential is greatly enhanced. Techniques have become widely available to visualize coelomic cavities and even fascial compartments, and these will be mentioned.

Gastroscopy

Gastroscopy (oesophagogastroduodenoscopy) allows visualization of the oesophagus, stomach and duodenum under light sedation. The patient is placed in the left lateral position, head on a pillow, and the neck slightly flexed. The throat is sprayed with lignocaine, and either diazemuls or midazolam may be used for sedation, though often none is required. The gastroscope is manoeuvred into the pharynx, and the patient is asked to swallow, while the endoscope is gently inserted into the oesophagus. The endoscope has channels that allow for biopsies, suction, flushing. Air is blown through the endoscope to distend the gastrointestinal lumen in order to pass the endoscope under a clear field of view.

Gastroscopy is used for diagnostic purposes, for example, to localize the source of upper gastrointestinal bleeding or in the investigation of dyspepsia. It may also be therapeutic. Bleeding gastric or duodenal ulcers may be injected with a solution of adrenaline which may reduce the incidence of rebleeding. Oesophageal strictures maybe dilated after introduction of a guidewire past the stricture. Similarly, pyloric stenosis may be dilated. Malignant strictures of the oesophagus may be palliatively treated by laser via the endoscope.

Colonoscopy

This allows the full length of the colon to be examined under sedation. The bowel must be prepared prior to colonoscopy. It may be used for a great number of purposes: to confirm and assess the extent of colitis; to biopsy lesions identified on barium enema; to snare polyps and retrieve them for histology; regularly to followup colitics to check for malignant or dysplastic changes; to differentiate acute colonic pseudo-obstruction from

organic causes of obstruction and to deflate the colon; to identify angiodysplasias in the colonic mucosa (a source of bleeding) and to treat them.

Proctosigmoidoscopy

In the general surgical outpatient department, proctoscopy and rigid sigmoidoscopy are invaluable. Proctoscopy examines the anus and the distal folds of rectal mucosa, and sigmoidoscopy is used to visualize the rectum. In the presence of an acute anal condition such as thrombosed haemorrhoids, fissure-in-ano or anorectal abscess, proctoscopy and sigmoidoscopy should not be performed. The anal canal will almost certainly be in spasm, and the procedure will be exceptionally painful, if not impossible.

On proctoscopy, first-degree (bleeding) haemorrhoids can be injected with 3% phenol to good effect, and second-degree (prolapsing) haemorrhoids can be banded. Sigmoidoscopy will identify proctitis and biopsies can be taken. Polyps and rectal carcinomas may be seen and biopsied. Flexible sigmoidoscopy enables a view through to the sigmoid colon, and this can be performed in the outpatient setting.

Endoscopic retrograde cholangiopancreatography (ERCP)

ERCP is performed using a side-viewing gastroduodenoscope. The ampulla of Vater is identified and cannulated. Contrast is injected and radiographs outlining both the biliary tree and pancreatic duct are obtained. Biliary strictures and bile duct calculi can be identified. Chronic pancreatitis results in characteristic pancreatic duct strictures with intervening dilated segments. Brushings and biopsies of neoplastic obstructions of the common bile duct or ampulla may be obtained for diagnostic purposes. ERCP also has important therapeutic roles. The sphincter of Oddi can be incised (sphincterotomy) to extract biliary calculi thus relieving obstructive jaundice. Stents can be inserted to bypass structures or obstructing calculi. The combination of ERCP followed by laparoscopic cholecystectomy has almost replaced the operation of open cholecystectomy, intraoperative cholangiography and exploration of the common bile duct. ERCP may be complicated by acute pancreatitis or (rarely) haemorrhage following a sphincterotomy.

Intraoperative endoscopy