Flexible sigmoidoscopy is a technique used to inspect the lower half of the colon, the rectum and the upper part of the anus.
Flexible sigmoidoscopy may be used as part of the investigation of rectal bleeding, to inspect the colon when only the bottom half needs to be inspected and as part of the screening program to prevent colon and rectal cancer.
Flexible sigmoidoscopy is a low risk procedure which requires the minimum of preparation. It is peformed on a daycase basis in most hospitals although is some clinics it is offered an out patient appointment (no bed required).
Prior to flexible sigmoidoscopy the lower bowel and recutum must be clean. This can be achieved either by using and enema or by in some hospitals by giving a full bowel prep. The enema is much more straight foreward but in some cases may not completely clear the lower bowel.
The investigation is performed under light sedation using Entonox. Entonox is a gas which is administered through a mouth piece attatched to a valve like a SCUBA valve. When you breath in the gas is released adn it stops as soon as you stop sucking. It is very easy to use and gives excellent pain relief without causeing too much sedation. Entonox wares off very quickly and so you have to breath it all of the time for it to be effective. Once the investigation is complete the effect of the gas will have completely worn off within 15 minutes.
The investigation is unertaken with the patient lying on their left hand side. The telesope is introduced via the anus and a small amount of air is introduced into the rectum. The instrument is then manipulated through the bowel until the desired level of insertion is achieved. The instrument is then removed and any biopsies required taken or polyps removed.
At the end of the procedure the air is removed from the bowel and the telescope taken out.
If flexible sigmoidoscopy is being undertaken for bright red rectal bleeding it may be possible to cauterise any small haemorrhoids or treat them by applying Barrons bands.