General and Colorectal

CASE 13: abDominal DiStenSion anD pain

history

A 70-year-old man has been sent to the emergency department from a nursing home, complaining of intermittent sharp abdominal pain. He has not opened his bowels for 5 days. He suffered a major stroke in the past and requires constant nursing care. He has a history of chronic constipation. Previous medical history includes chronic obstructive airways disease for which he is on regular inhalers. He is allergic to penicillin and is an ex-smoker.

examination

His blood pressure is 110/74 mmHg and the pulse rate is 112/min. His temperature is 37.8°C. There is gross abdominal distension with tenderness, most marked on the left-hand side. The abdomen is resonant to percussion and digital rectal examination reveals an empty rectum. There is a soft systolic murmur and mild scattered inspiratory wheeze on auscultation of the chest.

INVESTIGATIONS

an x-ray of the abdomen is performed and is shown in Figure 13.1.

Figure 13.1 plain x-ray of the abdomen.

Questions

•What does the abdominal x-ray show?

•What other radiological investigation could be employed if the diagnosis was in doubt?

•How should the patient be managed?

•What is the explanation for the pathology?

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100 Cases in Surgery

ANSWER 13

The x-ray shows a sigmoid volvulus. The sigmoid colon is grossly dilated and has an inverted U-tube shape. The involved bowel wall is usually oedematous and can form a dense central white line on the radiograph. On either side, the dilated loops of apposed bowel give the characteristic ‘coffee bean’ sign. X-ray appearances are diagnostic in 70 per cent of patients.

If there is doubt about the diagnosis, a water-soluble contrast may be helpful in showing a classical ‘bird’s beak’ appearance representing the tapered lumen of the colon.

!Treatment of sigmoid volvulus

•Keep patient nil by mouth

•intravenous access and fluids

•Fluid balance monitoring

•routine bloods and crossmatch

•erect chest x-ray/abdominal x-ray

•Decompression with rigid sigmoidoscopy and insertion of a flatus tube once the diagnosis is confirmed on abdominal x-ray

The flatus tube is left in situ for approximately 48 h and is often only a temporary measure. Colonoscopy can be used to decompress the bowel and may resolve the volvulus. Urgent laparotomy will be required if decompression is not possible or in cases of suspected gangrene/ perforation (fever, leucocytosis, peritonism, free air under the diaphragm on erect chest radiography). The patient’s fitness for surgery, prognosis and quality of life should be considered before proceeding to laparotomy. It may be appropriate to use only conservative treatments in some patients.

Sigmoid volvulus is predisposed to by a long, narrow mesocolon and chronic constipation. The rotation of the gut can lead to obstruction and intestinal ischaemia. The sigmoid is the commonest part of the colon for this to occur, although the caecum and splenic flexure are other potential sites.

KEY POINT

•in the presence of peritonitis or pneumoperitoneum, the patient should be considered for urgent laparotomy.

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General and Colorectal

CASE 14: anal pain

history

A 32-year-old man presents to the colorectal outpatient clinic with an 8-week history of pain on defaecation. The pain is around the anus and typically lasts an hour after passing stool. He normally suffers with constipation but this has now worsened as he is reluctant to pass motion because of the pain. He intermittently notices a small amount of fresh blood on the tissue paper after wiping himself. He has no family history of inflammatory bowel disease or colorectal cancer. He is otherwise well and takes no regular medications.

examination

The patient appears well with no evidence of pallor, jaundice or lymphadenopathy. Abdominal examination is unremarkable. Examination of the anus reveals a small linear defect in the skin at the 6 o’clock position. Rectal examination could not be performed as it caused too much discomfort for the patient.

Questions

•What is the most likely diagnosis?

•What are the typical findings on examination?

•What are the differential diagnoses?

•What treatment would you recommend?

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100 Cases in Surgery

ANSWER 14

The most likely diagnosis is an anal fissure – this refers to a longitudinal tear in the anoderm within the distal one-third of the anal canal. Examination typically reveals a linear tear in the midline and posteriorly. Anterior fissures are more common in female patients. Chronic fissures are associated with skin tags, and the exposed fibres of the internal sphincter may be visible at their base. Anal fissures are common in patients with Crohn’s disease and ulcerative colitis.

!Differential diagnoses

•perianal haematoma

•anorectal abscess

•anorectal carcinoma

•anal warts

•anal herpes

More than half of acute fissures will heal with conservative treatment. This should include the use of laxatives, high dietary fibre, fruit and plenty of fluids to ensure the stool is soft. Topical local anaesthetic (e.g. lidocaine) can be used for pain relief. Non-healing fissures may respond to the use of topical 0.2 per cent glyceryltrinitrate ointment. This ointment can cause headaches and dizziness, so is not suitable for all patients. Direct injection of botulinum toxin into the anal sphincter helps relieve spasm and promotes healing. Lateral sphincterotomy is used less frequently now as it is associated with a small risk of incontinence.

KEY POINT

•laxatives, high dietary fibre, fruit and plenty of fluids are effective conservative treatments for anal fissures.

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