From the Guidelines
Colonoscopy is generally safe, but it does carry some potential side effects and risks, including bleeding, perforation, and adverse reactions to sedation, with rates of serious bleeding events and perforations reported as 14.6 and 3.1 per 10,000 colonoscopies, respectively, as noted in a 2021 study 1.
Potential Side Effects and Risks
The potential side effects and risks associated with a colonoscopy procedure include:
- Common side effects: bloating, gas, mild cramping, and discomfort for a few hours after the procedure
- More serious but rare risks:
- Bleeding (especially if polyps are removed)
- Perforation (a tear in the colon wall) occurring in about 1 in 1,000 to 1 in 10,000 cases
- Adverse reaction to sedation
- Infection
- Missed lesions
Risk Factors
The risk of perforation increases with:
- Age
- Presence of diverticular disease
- Therapeutic interventions like polyp removal Bleeding typically occurs in 1-2% of cases where polyps are removed and usually stops on its own but occasionally requires treatment, as reported in a 2021 study 1.
Sedation Risks
Sedation risks include:
- Respiratory depression
- Allergic reactions
- Cardiovascular complications, though these are uncommon with modern monitoring
Patient Education
Patients should be educated about the range of possible post-procedure adverse events and associated symptoms, and instructed to contact their healthcare provider or seek emergency care if they develop severe abdominal pain, fever, significant bleeding, or other worrisome symptoms after the procedure, as recommended in a 2021 study 1.
Monitoring and Follow-up
Endoscopy units may consider adopting a process for systematic monitoring of delayed adverse events, such as scheduled phone calls, and monitoring of administrative data regarding post-procedure bleeding and perforation events, hospital readmission or emergency department visits, patient deaths, and interval CRC events, as suggested in a 2021 study 1.
From the Research
Potential Side Effects and Risks of Colonoscopy
The potential side effects and risks associated with a colonoscopy procedure include:
- Colonic perforation, which can lead to high morbidity and substantial mortality 2
- Bleeding, which can occur during or after the procedure 3, 4
- Adverse consequences of sedation, which can be a limitation of the procedure 5
- Inability to detect all colonic polyps, which can be a limitation of the procedure 5
- Serious complications, such as perforation or bleeding, which can be increased in certain patients 6
Patient-Based and Periprocedural Factors
Patient-based and periprocedural factors that may limit colonoscopy as a screening modality include:
- Patient perception and non-adherence to recommended testing 5
- Risk of complications, such as perforation or bleeding, which can be increased in certain patients 6, 3
- Use of antiplatelet agents and anticoagulants, which can increase the risk of bleeding during or after the procedure 4
Intraprocedural Factors
Intraprocedural factors that may limit colonoscopy as a screening modality include: