Surgery of the Large Intestine

What is your diagnostic approach to the large intestine?

Physical exam (rectal), radiographs and ultrasound, thoracic met check, colonoscopy, biopsy, baseline bloodwork

What are the surgical considerations for the large intestine?

Slower healing, poorer vascular supply, high bacterial content, lag phase is longer

What organ has collagen lysis > synthesis initially in the healing phase?

Large intestine

What suture material should you use on the large intestine?

PDS

What should you avoid before large intestine surgery and why?

Enemas because it is harder to deal with soupy feces than chunks

How can you clean out the colon?

48 hour fast, laxatives, multiple enemas

What are vesa recta?

Small vessels that are on the large intestine

T/F the majority of colonic masses are malignant?

True

What are the common colonic masses?

Adenocarcinoma

Leiomyoma, leiomyosarcoma

Lymphoma

What is the most common colonic mass?

Adenocarcinoma

What colonic mass is not surgical?

Lymphoma

What is the margin for colonic mass removal?

3-8 cm

What do you ligate when resecting the large intestine?

vasa recta individually

What causes megacolon?

End stage obstipation

Hypomotility causing permanent dilation

What is obstipation?

Severe constipation where you cannot pass stool

What is constipation?

Abnormally delayed or infrequent passage of dry, hard feces

What is another name for acquired megacolon

Hypertrophic megacolon

What causes colonic inertia?

Prolonged distention

Neurologic trauma

Congenital dysfunction

Endocrine disease

Idiopathic

What causes outlet obstruction?

Pelvic fracture malunion

Stricture

Neoplasia

Anal atresia or stricture

What are mechanical causes of megacolon?

Any form of outlet obstruction

T/F megacolon caused by a mechanical reason is reversible if removed early?

True

What are some functional causes of megacolon?

Spinal cord disease

Pelvic nerve injury

Dysautonomia

Manx cats

What is the most common cause of megacolon?

Idiopathic

What is the signalment for idiopathic megacolon?

Middle-aged and older cats

What is seen on the history of idiopathic megacolon?

Constipation/obstipation, depression, anorexia, tenesmus, weakness, vomiting/weight loss

What is the physical exam of idiopathic megacolon look like?

Lean body condition

Poor hair coat

Dehydration

Palpably distended colon

Rectal exam: hard feces at pelvic inlet

How do you diagnose idiopathic megacolon?

Abdominal radiograph

CBC/Chem

Eliminate underlying causes

What should you do for a first episode megacolon?

Manually remove feces

Administer laxatives

Prokinetic drugs

Ensure access to liter

Modify diet

What should you do for repeated episodes of idiopathic megacolon?

Perform subtotal colectomy

What do you do if there is constipation after colectomy to treat idiopathic megacolon?

Repeat clinical evaluation

Reinstitute medical therapy

Repeat subtotal colectomy with or without excision of the ileocecal valve

When should you go to surgical management for idiopathic megacolon?

When medical management fails

What is the problem with removing ileocecal valve to treat idiopathic megacolon?

It usually leads to diarrhea

What are the postop complications of idiopathic megacolon?

Leakage/dehiscence

Peritonitis

Stricture

Abscess

Persistent diarrhea

Recurrence

What are the clinical signs of large intestine disease?

Large bowel diarrhea, obstipation/constipation, tenesmus, hematochezia, anorexia, vomiting

What does large bowel diarrhea look like?

Mucoid and frequent