A colonoscopy procedure fails and aborts when the physician cannot advance the endoscopy tube to the juncture of the colon and small bowel. A number of events can complicate the procedure and cause this colorectal screening tool to be aborted.
Inadequate Bowel Preparation
When the physician performing the colonoscopy is unable to view the walls of the colon with the endoscopy tube, the value of the procedure is compromised resulting in the need to abort the colonoscopy. Mucous or stool remaining in the bowel are the most common reasons this can happen. Medication and enema preparation to prepare for the procedure relies on patient instruction and how well the patient actually follows and performs the bowel cleansing regimen with the prescribed agents.
Medication Reaction
Bowel cleansing medication given to patients orally prior to the procedure along with sedatives administered to patients prior to the colonoscopy can cause possible adverse reactions such as nausea and vomiting. These side effects along with bloating and rectal irritation also produced from the medication can cause the procedure to be aborted.
Perforation Risk
Another reason for aborting colonoscopy is bowel tears that occur as the physician performs the procedure. This is an extremely rare circumstance, but when it occurs the colonoscopy is aborted and the colon must be surgically repaired.
Procedure Intolerance
To be successful, patients must lie on their sides for some 30 to 40 minutes and undergo mild to unpleasant manipulation as the physician advances the endoscope in the bowel. Some patients will not tolerate the process long enough to complete the procedure and consequently the colonoscopy is aborted.
Equipment Issue
Occasionally, the endoscopy tube and/or visualizing equipment may be faulty and the procedure must be aborted.
Medical History
A patient who has undergone prior abdominal surgery or prior pelvic surgery may have previously undetected adhesions or changes within the colon that causes the endoscopy tube to be unable to advance through the bowel. Also, a history of diverticular disease within the past 10 years can cause the colonoscopy to be abandoned.
Colonoscopy Setting
According to the journal "Gastroenterology," colonoscopies performed in a private physician's office are more likely to fail than those procedures performed in an academic hospital. Findings indicate the volume of colonoscopies scheduled may at times exceed hospital procedure room availability and consequently, procedures are performed in the private office. There is no standard, however, for administering sedatives in office-performed colonoscopies; inadequate sedation may lead to discomfort during the procedure and therefore, a greater rate of abortion.
References
- "Gastroenterology": Factors Associated with Incomplete Colonoscopy; Hemant A. Shah et al; June 2007
- "Endoscopy": Colonoscopy Perforation Rate, Mechanisms and Outcome; V. Panteris; November 2009
