Colon and Rectal Surgery

Question 1

Give a basic description of the structure of the colon and rectum

Answer 1

Smooth muscle tube
Lined by epithelium
Enteric nerve supply

Question 2

Give a brief basic description of the function of the colon and rectum.

Answer 2

Fluid and electrolyte balance
Waste management
Continence

Question 3

What arteries does the superior mesenteric give off to supply the colon?

Answer 3

Middle colic artery
Right colic artery
Ileocolic artery

Question 4

What arteries does the inferior mesenteric give off to supply the colon?

Answer 4

Left colic artery
Sigmoid arteries
Superior haemorhoidal artery

Question 5

What is the name of the anastomosis between the superior and inferior mesenteric artery and what part of the colon does it exist?

Answer 5

Long anastomosis of Rolan

Splenic flexure

Question 6

How does the lymphatic supply of the colon lie in relation to the arterial supply?

Answer 6

Lymphatic supply follows the arterial supply

Question 7

What are the two anal sphincters and what role so they have in continence?

Answer 7

Internal anal sphincter = smooth muscle (controlled by the enteric nervous system)

External anal sphincter = skeletal muscle (controlled by you)

Question 8

Where does anorectal sensation come from and what role does the area play in discrimination?

Answer 8

Anorectal sensation comes from the distal portion of the rectum just before the anus.
It has the ability to discriminate between solids, liquids and gases so that you can pass wind without shitting yourself.

Question 9

What are the anal cushions?

Answer 9

The anal cushions are like vascular sacs that exist between the epithelium and muscle layers of the rectum.
These fill with blood and the sphincter muscles contract to seal off the anal canal.

Question 10

List some of the surgical problems of the colon and rectum.

Answer 10

Tumour - colorectal cancer

Inflammation - Ulcerative colitis, Crohn’s disease

Degeneration - Diverticular disease

Abnormal function - Constipation, incontenece, IBD

Gongenital - atresia, Hirschsprung’s disease

Question 11

What do patients complain of when presenting with colon and rectum problems?

Answer 11

• Change in bowel habit/ continence
• Bleeding
• Pain
• Non-Intestinal manifestations

Question 12

How should you proceed with someone presenting with real bleeding?

Answer 12

Rectal bleeding may be caused by colorectal cancer but investigation is not always required.

It is a very common problem:

• Of 2000 people
• 280-660 will get rectal bleeding at some point
• 14-30 will report to GP
• 1 will have bowel cancer

If patients have low risk features maybe watch and wait. (6 weeks)

Question 13

What are low risk features of rectal bleeding?

Answer 13

Transient symptoms (

Question 14

What are the high risk features of rectal bleeding?

Answer 14

Persistant change in bowel habit (>6 weeks)

Persistant rectal bleeding without anal symptoms

Right sided abdominal mass

Palpable rectal mass

Unexplained iron deficiency anaemia

Patients in whom there is clinical doubt

Question 15

What investigations can you carry out for rectal bleeding?

Answer 15

Colonoscopy (biopsy)

Flexible/rigid sigmoidoscopy +/- barium enema

CT colonoscopy

Question 16

What treatments are available for colorectal problems?

Answer 16

Medical vs. Surgical
Endoscoptic vs. invasive
Laparoscopy vs. laparotomy

Consider:

• Resection
• Restoration of continuity
• Preservation of function
• Fecal diversion

Question 17

What factors are important to ensure a successful bowel anastomosis?

Answer 17

Tension free
Well perfused
Well oxygenated
Clean surgical site
Acceptable systemic state

Question 18

What can some of the complications of surgery be?

Answer 18

Anaesthetic related
Bleeding
Sepsis
Venous thromboembolism
Anastomotic breakdown
Small bowel obstuction
Wound hernia