What are the complications of colonoscopy (Colonoscopy)?

From the Guidelines

Colonoscopy complications can range from minor to severe, with the most significant risks being bleeding and perforation, which can occur in up to 0.24% and 0.06% of cases, respectively, and can be life-threatening if not promptly addressed 1. The most frequent complications of colonoscopy include:

• Bleeding, which typically happens after polyp removal and may occur immediately or up to two weeks post-procedure
• Perforation, a serious complication affecting approximately 1 in 1000 colonoscopies, requiring immediate surgical intervention if detected
• Post-colonoscopy abdominal pain and distension, common minor issues that usually resolve within 24 hours
• Infection, rare but possible, particularly in procedures involving interventions like polypectomy
• Medication-related complications, including adverse reactions to sedatives, causing respiratory depression or cardiovascular instability
• Missed lesions, a diagnostic complication, with up to 6% of significant lesions potentially overlooked
• Splenic injury, extremely rare but can occur from excessive traction
• Post-polypectomy electrocoagulation syndrome, presenting as localized abdominal pain without perforation
• Vasovagal reactions, which can occur during the procedure, causing hypotension and bradycardia It is essential to inform patients about these potential complications during the consent process, and prompt medical attention should be sought for severe abdominal pain, significant bleeding, fever, or other concerning symptoms following colonoscopy 1. The risk of complications increases with patient age and comorbidity and performance of polypectomy, with most adverse events occurring within 14 days of colonoscopy 1. Endoscopy units should 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 1.

From the Research

Complications of Colonoscopy

• The most common complications of colonoscopy include vomiting, epistaxis, loss of consciousness with head injury, abdominal pain, acute diarrhea, symptoms of choking, heart rhythm disturbances, dyspnea, fractures of limbs and hands, acute coronary syndrome, hypotension, hypertension, cerebral ischemia, severe blood glucose fluctuations, increased muscle contraction, and allergic reactions 2
• Perforation is a rare but devastating complication of colonoscopy, with an incidence ranging from 0.012 to 0.65% during diagnostic procedures and higher in therapeutic procedures 3
• Early diagnosis and management of perforation are crucial to decrease morbidity, and diagnostic imaging after colonoscopy can reveal extraintestinal air 3
• Colonoscopic management of early perforations may be feasible and avoid the morbidity of surgery, while patients who require surgery may be managed with laparoscopic or open surgical techniques 3
• Mechanical bowel preparation before endoscopy decreases fecal contamination after perforation, often obviating the need for ostomy creation 3
• Postcolonoscopic perforation and bleeding can be treated nonoperatively with nothing by mouth, intravenous fluids, and antibiotics, and repeat colonoscopy with injection of epinephrine, respectively 4
• Improving techniques to avoid post-procedural complications have also been developed, further maximizing the utility of colonoscopy 5

Prevention and Management

• Individualization of recommended procedures and increased supervision of patients undergoing bowel cleansing procedure can reduce the occurrence of complications and side effects 2
• Quality assurance, through the development of widely accepted quality metrics, has offered measurable improvements in colonoscopic yield 5
• Significant improvements have been demonstrated in colonoscopic technique, from the administration of preparation to the techniques employed during withdrawal of the colonoscope 5
• Patient care before, during, and after the procedure is crucial, including consent, sedation, and bowel preparation within the context of the evidence base 6