Perforation injuries during this procedure result in a hole in the bowel. On average, this occurs in 1 in 1700 procedures. If procedures are performed during the colonoscopy to treat any problems, or if you already have significant colon or rectal disease, this risk is increased. For example, if a polyp is removed, the rate of perforation complications is about 1 in 700-800 procedures.
The size, location and seriousness of the hole can vary, and each perforation has different treatment options. Small perforations often seal themselves off, so they may only require a few days in the hospital with close observation. More serious injuries may require a surgery and possible repair or removal of the damaged area. Rarely a colostomy bag may need to be placed temporarily or permanently after the damaged bowel is removed. Loss of life is also a possible complication of serious perforations, however this is rare.