Endoscopy
Sometimes it is necessary to undertake an endoscopy (“camera test”) of the bowel in order to have a better understanding of the cause of your symptoms, or to help with operative planning. I undertake endoscopic assessment of the lower bowel, including colonoscopy, sigmoidoscopy and pouchoscopy, here in Worcestershire.
Colonoscopy
This is a complete assessment of the colon and rectum. At the time of the procedure it is sometimes possible to assess the last part of the small bowel. During the procedure, if any small polyps are found it is often possible to remove these at the same time. If there are a larger number of polyps, or polyps of a large size, then it may be necessary to return for a repeat procedure where enough time can be made available to remove these. Any samples taken during the procedure are sent to a pathologist for further assessment.
Flexible sigmoidoscopy
This is more limited assessment of the large bowel. It aims to assess the rectum and the lower half of the colon along the left side of the abdomen. It can normally be performed following the administration of an enema upon arrival to the endoscopy department. If polyps are identified you will require a colonoscopy at a later date to ensure there are not any further polyps in the parts of the colon not viewed in this test.
Pouchoscopy
This procedure allows for assessment of the ileal pouch in those patients who have had a pouch anal anastomosis or a continent ileostomy (Kock pouch) fashioned. Those patients with an ileoanal pouch normally require an enema on arrival in the endoscopy department, while those with a continent ileostomy can intubate the pouch and wash it out with water. The procedure can normally be performed without the need for intravenous sedation or pain relief. At the time of the procedure small biopsies are routinely taken for assessment by a pathologist.
Before and after your procedure
Before a colonoscopy, sigmoidoscopy or pouchoscopy can be performed, it is necessary to clear the bowel. This is to ensure that a good view of the bowel can be achieved. This may involve having to take some strong laxatives the day before the procedure (a must for colonoscopy), or for sigmoidoscopy and pouchoscopy, having an enema once you have been admitted to the endoscopy department. Sometimes, even for sigmoidoscopy, laxatives are given the day before.
When you come in for your procedure, you may choose to have sedation. This is normally given intra-venously and can make the procedure more comfortable. However, if you choose to have this, you cannot drive a car or sign legal documents for 24 hours following the procedure. An alternative is entonox (“gas and air”) which can be used during the procedure, but wears off very quickly. There are no restrictions after the procedure if you choose to have this. Some patients choose to have no sedation or entonox for their procedure, and this is more common if you are having a sigmoidoscopy or pouchoscopy.
Most patients remain in the endosocpy department for between 30 minutes and an hour after their procedure. If you have had sedation, a responsible adult will need to come and collect you. If you have not had sedation or have only had entonox, then you can leave the department on your own.
It is not uncommon to experience some abdominal discomfort or cramping after the procedure. This normally wears off within a few hours, but occasionally may persist for a couple of days.
If any polyps have been removed or biopsies taken then you may notice a small amount of blood when you go to the toilet. This should not exceed more than a couple of egg cupfuls. If a “dye spray” has been performed, then your stool may appear blue for a couple of days as the residual dye is cleared from the bowel.
Risk of the procedure
Unfortunately, all procedures carry risks of complications. Whilst these risks are normally small, it is important to be aware of what can go wrong.
The risks associated with endoscopy procedures include perforation, which occurs in less than 1 in 1000 procedures. This may be noticed at the time of the procedure, but sometimes occurs as a delayed complication up to a few days afterwards. If a perforation is noticed at the time of the procedure then you will be admitted to hospital for a period of observation and antibiotics. Management of this may require an operation, but this is not always needed. When a perforation occurs as a delayed complication, then this normally causes a sudden-onset severe abdominal pain. Should you experience this, then you should seek medical attention.
There is also a risk of bleeding, which is more common if larger polyps are removed or if you a taking any blood thinners (anticoagulants, eg warfarin or rivaroxaban). Bleeding will often stop without the need for major intervention, but it is often necessary to be admitted to hospital for observation.
Sometimes, abnormalities in the bowel can be missed at the time of the endoscopy. This is more likely if the laxatives or enema did not clear the bowel particularly well. Even in a clean-looking bowel, abnormalities may be tucked behind a fold in the bowel and therefore missed. Whilst the likelihood of this is small, if the bowel was not particularly clean then a repeat procedure with additional or different laxatives may be required.
Sometimes, when intravenous sedation is given, this may have more of an effect than expected and lead to the patient becoming over-sedated. If this occurs, drugs can be given to reverse the effects of the sedative. It is uncommon to have to do this.