- 15% colorectal cancers present with obstruction
- Most patients are over 70 years old
- Risk of obstruction greatest with left sided lesions
- Usually present at a more advanced stage
- 25% have distant metastases at presentation
- Perforation can occur at site of tumour or in a dilated caecum
Clinical presentation
- Caecal tumours present with small bowel obstruction
- Colicky central abdominal pain
- Early vomiting
- Late absolute constipation
- Variable extent of distension
- Left sided tumours present with large bowel obstruction
- Change in bowel habit
- Absolute constipation
- Abdominal distension
- Late vomiting
Investigation
- Plain supine abdominal x-ray will show dilated large bowel
- Small bowel may also be dilated depending on competence of ileocaecal valve
- Added value of erect film debatable
- If doubt over diagnosis or site of obstruction consider a water soluble contrast enema
Management
- All patients require
- Adequate resuscitation
- Prophylactic antibiotics
- Consenting and marking for potential stoma formation
- At operation
- Full laparotomy should be performed
- Liver should be palpated for metastases
- Colon should be inspected for synchronous tumours
- Appropriate operations include
- Right sided lesions – right hemicolectomy
- Transverse colonic lesion – extended right hemicolectomy
- Left sided lesions – various options
Three-staged procedure
- Defunctioning colostomy
- Resection and anastomosis
- Closure of colostomy
Two-staged procedure
- Hartmann’s procedure
- Closure of colostomy
One-stage procedure
- Resection, on-table lavage and primary anastomosis
- Three stage procedure will involve 3 operations!
- Associated with prolonged total hospital stay
- Transverse loop colostomy can be difficult to manage
- With two-staged procedure only 60% of stomas are ever reversed
- With one-stage procedure stoma is avoided
- Anastomotic leak rate of less than 4% have been reported
- Irrespective of option total perioperative mortality is about 10%
Bibliography
Carty N J, Ravichandram D.
The management of malignant large bowel obstruction. In:
Johnson C D Taylor I eds. Recent
advances in Surgery 19. Churchill Livingstone, London 1996: 1 -18.
Deans G T, Krukowski Z H, Irwin S T. Malignant obstruction
of the left colon. Br J Surg 1994: 81:
1270 - 1276.
Lopez-Kostner F, Hool G R,
Lavery I C. Management and causes of acute large bowel
obstruction. Surg Clin N Am 1997; 77: 1265-1587. |