March is Colorectal Cancer awareness month. To help raise awareness of
this condition, we will be sharing guest blogs by gastroenterologist
Dennis J. Ahnen M.D., AGAF, FACG of Gastroenterology of the Rockies.
Colonoscopy: What to Expect and Tips for Your Procedure
A colonoscopy is central to the care plan for families with hereditary
colorectal cancer (CRC) syndromes. Colonoscopic screening is the major
means for prevention and early detection of CRC. The main goals of a screening
colonoscopy are the early detection of CRC while it is still curable or,
better yet, prevention of CRC by detection and removal of pre-cancerous
polyps. However, colonoscopies and colonoscopists are not equal, as there
is surprisingly high variability in the quality of a colonoscopy.
Achieving a high-quality colonoscopy requires a joint effort by the patient,
the endoscopist and the endoscopy unit. There is general agreement about
important metrics for a high-quality colonoscopy, which include elements
that occur before, during and after the procedure.
Prep is critical to identify and completely remove colonic polyps, as this
requires good visualization of the entire colonic mucosa. A high-quality
endoscopy suite is expected to have good to excellent quality preps for
more than 85% of all colonoscopies. There are numerous colonoscopy preps
available but, unfortunately, they all induce dramatic diarrhea.
The prep is generally considered the most unpleasant part of the exam.
Better cleansing is obtained by using a split dose prep (half the night
before, half the day of the procedure). Other pre-procedure quality metrics
include an appropriate indication for the colonoscopy and proper informed
consent for the procedure.
What should you expect pre-procedure?
- Diarrhea and sleep disturbance.
- Detailed information/instructions for the recommended prep including dietary
restrictions, a description of what you will likely experience and the
side-effects that can arise (dehydration, vomiting).
- To be offered the option of a split prep.
- To learn whether you need to change any of your medications/supplements
prior to the examination.
- Which type of sedation will be used and the need to arrange for transportation.
- You should be able to find out how much the procedure will cost and how
much of that you will be expected to pay.
Tips for pre-procedure
- Get the prep kit several days prior to your scheduled procedure and read
and follow the instructions carefully. You don’t want to have a
poor-quality examination or to have to do the prep more than once.
- Accept a split prep when offered or ask about it if it’s not offered.
- Preps vary substantially in volume, palatability, and cost. Ask about your options.
- Propofol anesthesia is preferred over conscious sedation with drugs like
fentanyl and versed by many endoscopists (and patients) but it must be
administered under the direction of an anesthesiologist. It doesn’t
improve the quality metrics of the examination and it can add $500-$2,000
to the overall cost of the procedure.
- The Affordable Care Act requires insurance companies to cover the cost
of screening colonoscopies without copays but if a polyp is found or if
the test is done to evaluate symptoms or as a second step after another
type of screening test, it may be classified as a diagnostic examination
and, depending on your insurance coverage, you may receive a substantial bill.
During the Procedure
The single most important component of a high-quality colonoscopy is a
performance by a high-quality colonoscopist; one with a low interval CRC
rate (ICR). Although it currently isn’t feasible to routinely measure
ICRs, another more easily measured metric, the adenoma detection rate
(ADR), strongly correlates with the ICR. The ADR is the percent of average-risk
patients undergoing a screening colonoscopy who are found to have one
or more colonic adenomas. This is arguably the single most important metric
of a high-quality colonoscopist; the minimal acceptable ADR is
≥ 25% (≥ 20% in women,
≥ 30% in men).
In general, higher ADRs are found in providers who have had more endoscopic
training and those that do more colonoscopies. As a group, gastroenterologists
and colorectal surgeons have more extensive training, do more colonoscopies
and have higher ADRs than internists or general surgeon colonoscopists
but there are certainly exceptions to this generalization. ADRs can be
improved through education and training.
Additional metrics of a high-quality colonoscopist are a high rate of examinations
that are complete to the cecum (>95% for screening exams with good
preps), an adequate amount of time examining the mucosa on the way back
from the cecum (average > 6 minutes) and a low complication rate (serious
complications <1/1,000 procedures).
What should you expect during the procedure?
- A colonoscopy done by a high-quality colonoscopist.
- The colonoscopist should be well-trained, perform enough colonoscopies
to maintain technical expertise (some suggest >200/year) and have an
ADR of over (preferably well over) 30%.
- A high-quality colonoscopist should know and be willing to provide you
with his/her training, colonoscopy volume and ADR.
- The colonoscopy should be complete to the cecum and adequate time should
be taken to carefully examine the colon.
Tips for during the procedure
- Colonoscopy is highly effective but it is not perfect. The miss rate for
CRCs is estimated to be 2-6% overall and even high-quality endoscopists
occasionally miss CRCs. The miss rate for precancerous polyps is higher.
- Colonoscopy is safe but serious complications such as perforations and
bleeding do occur rarely (<1/1000 procedures).
- Colonoscopy is expensive. In a highly publicized (and criticized) article,
the NY Times reported costs as high as $4,000-$8,500 in cities across
Quality metrics after completion of colonoscopy include the generation
of a high-quality endoscopy report and appropriate follow-up recommendations.
What should you expect post-procedure?
- To receive a copy of a high-quality endoscopy report. It should document
the indication for and extent of the exam, the quality of the prep, describe
all abnormalities found including the number, size, location and appearance
of any polyps and how they were removed; photo-documentation of important
findings is preferred.
- To receive instructions on the symptoms associated with serious post-colonoscopy
complications and information about who to contact for questions/concerns.
- To receive your pathology results and recommendations for follow-up.
Tips for post-procedure
- Inform your family about your colonoscopy findings. If you have a CRC or
an advanced polyp, it may have implications for the cancer risk in your
Contact Gastroenterology of the Rockies to Schedule an Appointment
If you’d like to learn more about prevention and screening for CRC
or wish to schedule an appointment for a colonoscopy, please call Gastroenterology
of the Rockies at 303-604-5000.