For inspection of the bowel alone, complications of colonoscopy are uncommon. Most surveys report complications in 1 in 1,000 examinations or less. Complications which can occur include an intolerance of the bowel preparation solution or reaction to sedatives used. Perforation (making a hole in the bowel) or major bleeding from the bowel is extremely rare but if it occurs, may require surgery.
When operations such as removal of polyps are carried out at the time of examination there is a slightly higher risk of perforation or bleeding from the site where the polyp has been removed.
Complications of sedation are uncommon and are usually avoided by administering oxygen during the procedure and monitoring oxygen levels in the blood. Rarely however, in patients with severe cardiac or chest disease serious sedation reactions can occur.
A number of rare side effects can occur with any endoscopic procedure. Death is a remote possibility with any interventional procedure. If you wish to have full details or rare complications discussed, you should indicate to your doctor before the procedure that you wish for all possible complications to be fully discussed.
Because of the risk of cancer, it is recommended that all polyps found at the time of colonoscopy be removed. However, it will not be possible to discuss the removal with you at the time of examination as you will be sedated. Therefore, if you agree to having removed any polyps found during the procedure, please sign the consent form. If you have any queries or reservations about this, please inform your doctor.
In the unlikely event of haemorrhage occurring, blood transfusion may be necessary.