CGRN - Certified Gastroenterology Registered Nurse Lower Endoscopy Procedures Questions and Answers

Question 1

A CGRN is reviewing a procedure report that describes the patient's colonoscopy preparation using the Boston Bowel Preparation Scale (BBPS). The scores are: Right colon=2, Transverse colon=1, Left colon=2. How should the nurse interpret this finding?

Accepted Answer

The total score of 5 indicates an inadequate preparation, requiring a shorter interval for repeat examination.

Answer

The Boston Bowel Preparation Scale (BBPS) scores each of three colon segments from 0 (unprepared) to 3 (excellent). A score of 1 in any segment indicates that portions of the mucosa could not be seen, rendering the overall preparation inadequate. A total score of 5 or less is considered poor, which is associated with a lower polyp detection rate and necessitates a repeat colonoscopy at a shorter interval than standard guidelines would otherwise suggest.

Question 2

A patient calls the gastroenterology unit 10 hours after a colonoscopy with polypectomy. The patient reports a sudden onset of severe, constant abdominal pain, a fever of 101.2°F (38.4°C), and states their abdomen feels "hard as a rock." The CGRN should recognize these signs as most indicative of which complication?

Accepted Answer

Bowel perforation

Answer

The combination of severe, constant abdominal pain, fever, and a rigid, board-like abdomen are classic signs of peritonitis, which is most commonly caused by a bowel perforation in this context. This is a medical emergency requiring immediate evaluation. Post-polypectomy syndrome can present with similar pain and fever but is a transmural burn without a frank perforation and typically does not cause profound abdominal rigidity. Delayed hemorrhage would present with rectal bleeding.

Question 3

During a colonoscopy, the endoscopist works to advance the scope to the beginning of the large intestine. Which of the following is considered the most definitive photographic evidence that cecal intubation has been achieved?

Accepted Answer

Identification of the appendiceal orifice

Answer

The appendiceal orifice and the ileocecal valve are the two definitive landmarks proving the cecum has been reached. Photographing the appendiceal orifice confirms that the entire colon has been examined. While entering the terminal ileum also confirms cecal intubation, the appendiceal orifice is a landmark within the cecum itself. The hepatic flexure is a landmark passed earlier in the procedure, and haustral folds are present throughout the colon.

Question 4

A CGRN is preparing a 70-year-old patient with a history of Stage 4 chronic kidney disease and congestive heart failure for a colonoscopy. Which type of bowel preparation regimen is absolutely contraindicated for this patient due to the risk of acute phosphate nephropathy and severe electrolyte shifts?

Accepted Answer

An oral sodium phosphate (OSP) based solution.

Answer

Oral sodium phosphate (OSP) preparations are absolutely contraindicated in patients with moderate to severe chronic kidney disease (Stage 3-5), heart failure, or liver disease. They can cause significant fluid shifts and electrolyte disturbances, including hyperphosphatemia, which can lead to acute phosphate nephropathy and worsening renal failure. Polyethylene glycol (PEG) based solutions are the safest alternative as they are iso-osmotic and not absorbed systemically.

Question 5

What is the primary advantage of using carbon dioxide (CO2) for insufflation during a colonoscopy as compared to using ambient room air?

Accepted Answer

It reduces post-procedure abdominal pain and bloating.

Answer

Carbon dioxide is absorbed from the colon into the bloodstream approximately 150 times faster than the nitrogen in room air. This rapid absorption and subsequent exhalation via the lungs leads to less residual gas in the bowel, which significantly reduces post-procedure abdominal pain, cramping, bloating, and discomfort for the patient. Visualization is comparable, and CO2 requires additional equipment, making it more expensive than room air.

CGRN - Certified Gastroenterology Registered Nurse Practice Test

CGRN - Certified Gastroenterology Registered Nurse Practice Test

CGRN - Certified Gastroenterology Registered Nurse Lower Endoscopy Procedures Questions and Answers