Colonoscopy

What is colonoscopy?

Colonoscopy is a commonly performed procedure used to examine the colon and rectum. Colonoscopy can detect inflamed tissue (Crohn’s Disease or Ulcerative colitis), ulcers, and polyps. The procedure is used to look for early signs of colorectal cancer and can help doctors diagnose unexplained changes in bowel habit, abdominal pain, bleeding from the anus, and weight loss. It is a safe procedure and forms the basis of most form of screening programmes bowel cancer. Most of the risk associated with colonoscopy relates to the removal of benign growths termed polyps, which have the potential overtime to progress to colon cancer.

What are the colon and rectum?

The colon and rectum are the two main parts of the large intestine. Although the colon is only one part of the large intestine, because most of the large intestine consists of colon, the two terms are often used interchangeably. The large intestine is also sometimes called the large bowel. It is approximately 1.5 m in length About 1.5 litres of digestive waste (mainly water & fibre) enters the colon from the small intestine as a semisolid over a 24-hour period. As waste moves toward the anus, the colon removes water and forms stool. Only about 100 mls of water is passes in the stool per day under normal conditions. The rectum is about 15 cm long and connects the colon to the anus. Stool leaves the body through the anus. Muscles and nerves in the rectum and anus control bowel movements.

Is it a painful procedure?

Colonoscopy can be uncomfortable at times and sedation tends to be given routinely to patients undergoing colonoscopy. It is not uncommon for patients to decline sedation and tolerate the procedure very well. As tolerance is so variable, it is important to let the endoscopist and nursing team know if you are experiencing discomfort during the procedure. Discomfort usually relates to stretching of the bowel wall and is very transient. Often the endoscopist is aware of the potential for discomfort due to “looping” of the colonoscopy. Experienced colonoscopies can minimize this “looping” leading to a relatively painless procedure. However at times “looping” still occurs and more sedation can be given.