Diagnostic and therapeutic colonoscopy represents one of the mandatory skillsets of
gastroenterology (GI) training. This is typically done in a step-up fashion of learning
basic (e.g., colonic navigation, prevention of looping), intermediate (e.g., forceps
biopsy, basic polypectomy), and advanced techniques (e.g., large polyp resection).1
At any point during the training process, complications can develop, and colonic perforation
still stands as the most disruptive complication for patients, families, and healthcare
professionals, with reported mortality rates of up to 5%.2 While feared by trainees,
colonoscopy perforations are rare and may not even occur during a 3-year GI fellowship.
Several studies have shown that the risk of perforation is 1:1,400 for diagnostic
and 1:1,000 for therapeutic colonoscopy.2 Therefore, a trainee who performs 400–500
colonoscopies has approximately 1:2 to 1:3 odds of encountering a colonic perforation
during training. These estimates may be higher in trainees exposed to endoscopic mucosal
resection (EMR) or submusosal dissection (ESD), which carry perforation risk of 1%
and 5%, respectively.2
Limited endoscopic experience is a risk factor for colonoscopy perforation. Compared
with GI physicians, colonoscopy performed by GI trainees or surgeons carries a higher
risk of perforation.3,4 In early stages of training, this may be associated with mechanical
damage (e.g., retroflexion in a small rectum, fixed angulation, excessive looping)
or air insufflation. Later during fellowship, perforations are more likely to be caused
by therapeutic interventions. Removal of difficult polyps (e.g., large polyps, cecal
location) is associated with higher risk of perforation. During the first years in
practice, gastroenterologists should be cautious and ask the opinion of a more experienced
endoscopist before starting a possibly complex polypectomy. Selecting which polyps
are removable and recognizing personal technique limitations are skills that every
competent gastroenterologist should develop to reduce colonoscopy complications and
assure complete polyp resection.
Colonic perforations caused by mechanical injury are typically large and can be detected
during the procedure. In contrast, perforations caused by endoscopic interventions
are smaller in size and more frequently have a delayed presentation. When a perforation
is found during the procedure, the first rule is not to panic. The gastroenterologist
in charge should decide whether conservative, endoscopic, or surgical management is
preferred. Calling a surgeon, an advanced endoscopist, and a senior gastroenterologist
into the endoscopy suite as quickly as possible helps to make a multidisciplinary
decision based on local expertise. In the last 20 years, there has been increasing
experience with the use of different devices for endoscopic closure of colonic perforations.
This ranges from the simple use of through-the-scope clips to more complicated methods,
such as over-the-scope clips, endoscopic suturing, colonic stents, or glue.5 While
these techniques are usually learned during advanced endoscopy training, any GI fellow
should be familiar with the use of at least through-the-scope clips for perforation
closure. Surgery should be avoided if possible, as this is associated with increased
mortality, prolonged hospital stay, and postoperative morbidities.6
Fellows may encounter consults or patient calls for abdominal pain following a colonoscopy.
This requires immediate clinical evaluation to rule out delayed perforation. In the
presence of diffuse peritoneal signs or hemodynamic instability, surgery is typically
indicated. If the pain is localized and the patient is stable, an upright X-ray or
cross-sectional imaging must be obtained. If free air is not the cause, the pain could
be explained by postpolypectomy coagulation syndrome or other reasons, and it likely
can be managed conservatively. The presence of free air on imaging typically leads
to surgery, but conservative management should be considered in select cases. Sometimes
free air can be detected on imaging following EMR or ESD in the absence of true perforation.7
In these situations, pain may be transient or completely absent, and conservative
management is preferred.
Operator stress and burnout can follow a colonoscopy perforation.8 GI fellows are
less used to morbid complications than trainees in surgical specialties, despite the
mandatory training in internal medicine. For any fellow who encounters this complication,
sharing the experience with other fellows, experienced faculties, mentors, or the
program director can be helpful to reduce stress and to learn from others’ experiences
with colonoscopy perforation. Fellows should present this complication in a morbidity
and mortality conference to enrich the education of other fellows who may not encounter
this during training. A discussion should be focused on the mechanism of the perforation,
precipitating factors, treatment options, and future preventive strategies.