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What is a Colonoscopy?

A colonoscopy is a procedure used most commonly to screen for colon cancer and/or to identify and correct bleeding problems. Colonoscopy is also used to evaluate persistent diarrhea, abdominal pain, and change in bowel habits. The colonoscope is a long thin flexible tube. At the tip is a video camera which projects images of the colon onto a large monitor.The colonoscope also has tiny channels in the tube for flushing water, for inflating and deflating the colon, and for passing small instruments during the procedure.

Colonoscopy is usually an outpatient procedure that the Gastroenterologist performs at an endoscopy center. During a colonoscopy, the Gastroenterologist might perform any number of tasks depending on findings. These include: taking photos to document findings, sampling tissue to submit to the lab for biopsies, removing precancerous polyps, dilating areas of narrowing, or performing cautery or applying clips to stop bleeding.

The Gastroenterologist will inject intravenous (IV) sedation to keep you drowsy and comfortable during the entire procedure.

Uses of Colonoscopy

Colonoscopy is an important way to check for colon cancer and to remove polyps, (abnormal growths on the inside lining of the colon). Polyps vary in size and shape and they usually cause no symptoms. A physician is unable to predict whether a polyp is malignant or premalignant by visual appearance. Since most cancers of the colon start out as benign polyps years before cancer develops, the best strategy for colon cancer prevention is to perform periodic colonoscopy to find and remove polyps. The technique of removing polyps via colonoscopy is called polypectomy.

The Gastroenterologist can limit insertion to the lower part of the large intestine (rectum, sigmoid, and descending colon). This limited insertion is called flexible sigmoidoscopy. Alternatively, the GI physician could advance the scope through and beyond the colon and into the last part of the small intestine called the terminal ileum. The length of colon/small intestine to examine depends on the reason for performing the procedure.

How do I prepare for my colonoscopy?

The office will provide you with detailed instructions about how to prepare for colonoscopy, with details how to thoroughly clean out the colon. This clean-out tends to be somewhat tedious and unpleasant, but most patients tolerate this without major problem. The success of colonoscopy will depend on how well the bowel is cleaned out. A colon with residual stool can’t be optimally inspected.

Various methods can be used to help cleanse the bowel, and your doctor will recommend what he or she prefers in your specific case. A clear liquid diet is taken for part or all day prior to the colonoscopy. Most typically, the patient will drink a liquid preparation that will stimulate bowel movements beginning the evening prior to the procedure.The prep is typically “split” into different portions to keep it more tolerable to take AND to better clean out the upper end (right side) of colon. Better view of the right side of the colon is crucial because flatter more subtle polyps commonly develop there. Whichever clean-out methods are recommended for you, be sure to follow instructions as directed.

Follow Directions

The colonoscopy prep reduces high roughage foods (nuts, seeds etc.) for a few days before the exam. Carefully review instructions about what to eat or drink the day before your colonoscopy, and what time to stop all food and fluid intake. You should receive specific instructions about what medications to continue, stop or modify prior to and through the day of the procedure. This is especially important for patients taking blood thinners, diabetic medication, and blood pressure medications. Colonoscopy is usually done at an outpatient endoscopy/surgery center or sometimes at the outpatient section of a hospital. You’ll get specific instructions where to go and when to arrive. After registering and presenting insurance information and (if needed) insurance pre-authorization forms, you will sign a form that verifies that you consent to having the procedure and that you understand what is involved. If there is anything that is not clear, be sure to ask for more information and clarification.

How is the colonoscopy performed?

First, you will change into a patient gown. Don’t wear makeup or bring unnecessary jewelry to the endoscopy center. During the procedure, we emphasize patient safety and comfort. A nurse or anesthesiologist will insert an intravenous line, or IV, and will administer medication to make you very sleepy (and generally unaware of the procedure).There are generally two sedation options, moderate sedation and deep sedation. Deep sedation with Propofol requires the presence of an Anesthesia professional. We will discuss with you these sedation options prior to the procedure Occasional patients prefer to receive NO sedation. Once you are adequately sedated, your doctor will first do a digital rectal exam with a gloved, lubricated finger followed by insertion of the lubricated colonoscope. As the physician advances the scope and distends the colon with air or CO2 to open-up the colon for scope passage, you might experience a sensation of cramping or urgency, depending on the level of sedation achieved.

Generally, there is little or no discomfort. The physician can pause the colonoscopy to administer additional sedation, in the event of patient discomfort or intolerance. The time needed for colonoscopy will vary, depending in part on what is found and what is done. On average, the procedure takes about 30 minutes. Afterwards, our nursing staff will monitor and care for you in a recovery area until the effects of the medication have worn off. At that time, your doctor will inform you about the results of your colonoscopy and provide any additional information you need to know. We will also provide you with instructions regarding how soon you can eat and drink, plus other guidelines for resuming your normal routine. Before you leave, we will give you a copy of the colonoscopy report with photos, and will forward a copy to your referring physician. We will send any tissue specimens removed during the colonoscopy to the lab for a pathologist to analyze.

After your Colonoscopy

You will need to arrange for someone to drive and take you home after the colonoscopy. Taxi, bus and ride share is NOT typically allowed when sedation has been provided. You can resume a normal diet and your normal medication after you leave the unit. Sometimes, after colon polyp removal, your physician might request that you delay restarting blood thinners for a specified time, to prevent bleeding. You can usually resume normal or light activity for the remainder of the day of the exam, and you can drive the day after the exam. There are no restrictions on driving or activity the day after the exam. Occasionally, minor problems may persist, such as bloating, gas or mild cramping, which should disappear in 24 hours or less.

What are the risks of a colonoscopy procedure?

Although colonoscopy is a safe procedure, complications can occur. These include: perforation or puncture of the colon walls which could require surgical repair, missing some colon lesions (abnormalities), and bleeding after a biopsy or removal of a polyp. If bleeding is serious, it might require a blood transfusion or reinsertion of the colonoscope to control the bleeding. Be sure to talk with your doctor if you have any questions or concerns.

What are my alternatives to this procedure?

Although a colonoscopy is considered to be the “gold standard” to diagnose colon cancer and to diagnose and remove precancerous polyps, some patents prefer other, less invasive options. It is ALWAYS better to do SOME kind of screening rather than NOTHING, since colon cancer is the second most common cause of cancer death. Two kinds of fecal tests are available for screening. One, for detection of occult (hidden) blood is called a FIT test, and must be done yearly to have much value. Another for detection of both occult blood and cancer genetic material is called Cologuard®. Another option is a CT scan of the colon, often referred to as ‘virtual colonoscopy’ or CT colonography. The last alternative is a sigmoidoscopy, which is essentially an abbreviated colonoscopy in that the physician examines just the lower ¼ to 1/3 of the colon with a shorter scope. This procedure is best for those with low risk for colon cancer, namely those with no family history and no previous polyps. A video capsule exam is being developed but is still investigational and not covered by insurance, nor do we believe yet that it is a good alternative. Note that any positive alternative test MUST be followed by a colonoscopy. All the alternative screening tests to colonoscopy can miss polyps or cancer (false negatives) or can return positive when nothing turns out to be wrong (false positives). Consult with your Gastroenterologist if you have questions about the accuracy of any of these diagnostic tests.

What about insurance coverage?

Medicare and almost ALL private insurance including HMOs covers colonoscopy for screening with no copay or deductible. Follow-up exams after polyp removal usually do have some copay or deductible. Fecal blood tests are usually covered, Cologuard sometimes; CAT scan colonography has very limited coverage. Video colon capsule testing is not yet covered.

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