Introduction
- Resection of 90-95% of the colon followed by anastomosis comprises subtotal colectomy.
Uses
- In the treatment of constipation/obstipation caused by megacolon
. - Causes of megacolon in cats include:
- Congenital lesions.
- Neurological dysfunction or injury.
- Prolonged distension.
- Idiopathic.
- Outlet obstruction (eg pelvic canal narrowing due to fracture malunion; stricture; neoplasia).
- Behavioral.
- Most cases in cats are either idiopathic or arise due to pelvic fracture or sacroiliac luxation that has caused pelvic canal narrowing.
Advantages
- Provides a surgical solution to an often intractable and recurring problem that may prompt owners to request euthanasia.
Disadvantages
- Once more than 70% of the colon is resected loose feces/diarrhea result, though these symptoms commonly abate after a period of 1-2 months. Fecal consistency usually becomes acceptable, although the cat may defecate more often than normal.
Requirements
Materials required
Minimum equipment
Ideal equipment
- Suction.
Minimum consumables
- Polydioxanone or polyglyconate suture material is recommended (3/0 and 4/0).
- Laparotomy sponges/towels.
Preparation
- 15 minutes.
Preoperative enemas are unnecessary - it is difficult to remove all material and the fecal slurry produced may make intraoperative contamination more (not less) likely. - Cats with severe and chronic obstipation may be dehydrated, toxic and have electrolyte disturbances from vomiting. They should be assessed and stabilized preoperatively.
- Preoperative antibiotics
should also be administered; drugs should be effective against the aerobic and anaerobic species encountered in the colon.
Sequelae
Complications
- Stricture: if excessive inversion or eversion suture techniques are used. Uncommon with appositional closure.
- Incontinence: rare.
- Diarrhea: sometimes due to small intestinal bacterial overgrowth.
Note that loose feces are expected for several weeks postoperatively, until the small intestinal absorptive capacity increases to cope with the shortened colon. Ensure owners are made aware of the fact that loose and frequent feces can persist for up to 6 weeks postoperatively. Most cats then regain a much more normal fecal consistency, although frequency of defecation may remain elevated. - Constipation
may occasionally recur. - If problems arise specific diets are available which will assist in modifying fecal consistency.
Prognosis
- Generally good to excellent.
Reasons for treatment failure
- Insufficient removal of colon may result in persistent constipation.
Sources
Publications
- De Haan J J et al (1992) Surgical correction of megacolon in cats. Feline Practice 20, 6.




