Practical Gastrointestinal Endoscopy

PATIENT CARE 27
Endoscopy databases should capture all such events, and allow
attribution options.
Complication rates
The problems of definition and data collection make it difficult to
quote meaningful global statistics about the risks of endoscopy.
Large surveys suggest that the chance of suffering a severe complication
(such as perforation or cardiopulmonary dysfunction)
after routine upper endoscopy is less than one in 500 cases. The
risks are higher in the elderly and acutely ill, and during therapeutic
and emergency procedures. Inexperience, oversedation
and overconfidence are important factors.
Specific events
• Hypoxia should be detected early by careful nursing surveillance
aided by pulse oximetry. Sometimes it is necessary only
to ask the patient to breathe more deeply, and to provide oxygen
supplementation. Reversal agents may be necessary.
• Pulmonary aspiration is probably commoner than recognized.
The risk is greater in patients with retained food residue (e.g.
achalasia, pyloric stenosis), and in those with active bleeding.
• Bleeding may occur—during and after endoscopy—from existing
lesions (e.g. varices), or due to endoscopic manipulation
(biopsy, polypectomy) or, occasionally, due to retching from a
Mallory–Weiss tear. The risk of bleeding is greater in patients
with coagulopathy, and in those taking anticoagulants and (possibly)
antiplatelet agents.
• Perforationis the most feared complication of upper endoscopy.
It is rare, but most commonly occurs in the neck, and is more
frequent in elderly patients, perhaps in the presence of a Zenker’s
diverticulum. The risk is minimized bygentle endoscope insertion
under direct vision. Perforation beyond the cricopharyngeus
is extremely unusual in patients who are not undergoing
therapeutic techniques such as stricture dilatation, polypectomy
or mucosal resection. Perforation at colonoscopy is discussed in
Chapter 7.
• Cardiac dysrhythmias are extremely rare, and require prompt
recognition and expert treatment.
• Intravenous (IV) site problems. Many patients have discomfort
at the site of their intravenous infusion; local thrombosis is not
unusual or dangerous, but evidence of spreading inflammation
should be treated promptly and seriously.
• Infection. Endoscopes (and accessories) are potential vehicles
for the transmission of infection from patient to patient (e.g. Helicobacter
pylori, salmonellas, hepatitis, mycobacteria). This risk
should be eliminatedby assiduous attention to detail in cleaning
and disinfection. Endoscopy can provoke bacteremia, especially