A colonoscopy is a safe and minimally invasive procedure, in which a trained physician uses a special instrument called a colonoscope to view the large intestine (also known as the colon) and rectum. Colonoscopies are used to screen for colon cancer and polyps, and to evaluate for inflammatory bowel disease and other diseases of the colon. The procedure is done on an outpatient basis, which allows patients to return home the same day as the exam.
The day before a colonoscopy, patients will need to stay on a clear liquid diet and drink a special laxative preparation to help empty the large intestine. Quick access to the bathroom is helpful during preparation, as the laxative preparation will lead to diarrhea. It is essential to follow the doctor’s instructions carefully, as a clean colon is essential during the colonoscopy.
On the day of the exam, sedation is administered intravenously by our anesthesia staff, so that the patient will be relaxed throughout the procedure. The patient will lie on their left-hand side on an exam table during the procedure, and a thin, flexible colonoscope is inserted into the anus and passed through the rectum and large intestine. Air is then introduced gradually so that the physician can easily view the lining of the colon. Images of the colon are projected onto a video monitor from a special camera at the end of the colonoscope. Polyps can be removed and biopsies of abnormal findings can be obtained during the colonoscopy. Polyps are usually benign, but they can be precancerous, so it is important to have them removed. Colonoscopies are typically very safe and take between twenty to forty-five minutes to perform. You should plan on spending approximately 2-3 hours at the center on the day of your procedure.
A colonoscopy can be performed to screen for colon cancer in individuals over the age of 45 to 50. Colonoscopy may even be performed at an earlier age if a patient has an early personal or family history of colon cancer or polyps. According to the American Cancer Society, colon cancer is the second leading cause of cancer-related death in the United States. The average adult has about a 1 in 20 chance of being diagnosed with colon cancer, although this varies widely, depending on individual risk factors. Even though colon cancer is on the rise in the US (an estimated 140,250 new cases in 2019), it is relatively treatable when caught early, which is why colon cancer screening is so important. It is estimated that increased awareness of and screening for colon cancer would save at least 30,000 lives each year. Colonoscopies may also be recommended by a doctor to diagnose the cause for symptoms such as rectal bleeding and chronic diarrhea.
It is often said that preparation is the hardest part of a colonoscopy. Your doctor will explain dietary restrictions and colonoscopy preparation prior to scheduling your colonoscopy. The following are some examples of colonoscopy preparations:
Although most medications can be taken as usual, it is important to let your doctor know all medications that you take, because it is possible that they may need to be stopped temporarily prior to your procedure. In particular, let your doctor know if you take aspirin, arthritis medications, anticoagulants (blood thinners such as Warfarin, Lovenox, Plavix, Eliquis, Xarelto, Brilinta, Pradaxa, Effient), medications for diabetes, or iron products. Allergies to any medications should also be mentioned before the exam.
As mentioned above, physicians can sometimes find polyps during the examination. Polyps are abnormal tissue growths that are often small, flat bumps, less than half an inch wide, but can vary in size from a tiny dot to several inches. Rarely, polyps can be malignant (cancerous). However, most polyps are benign (non-cancerous). A colonoscopy is the best way to detect polyps while they are small and removable. Colon polyps can develop into colon cancer, so removing them is an important way to prevent colorectal cancer.
There are a handful of ways that a physician will remove polyps. One method is called “snare polypectomy,” which uses a wire snare and is implemented to remove polyps. During a polypectomy, a doctor will advance a small wire loop through the colonoscope and remove the polyp. Occasionally, this is performed with an electrical current. Physicians will also use biopsy instruments to remove smaller polyps. None of these methods should cause the patient any pain or discomfort.
After the colonoscopy is completed, the patient will wake up within a few minutes. There will then be a period of time where the patient is monitored until most of the anesthesia has worn off, and then they can be discharged unless a physician instructs otherwise. The physician who performed the procedure will explain the results, and let the patient know if there were any biopsies performed. Biopsy results are usually available within one week. As anesthesia is administered as part of the examination, the patient will need to have someone drive them home and stay with them. Additionally, the stomach may feel cramped or bloated due to the introduction of additional air during the exam. These symptoms should disappear once the patient has passed gas. Patients may eat immediately after the procedure unless their doctor gives other instructions.
Complications during a colonoscopy or polypectomy are rare, however one possible complication is a perforation, or tear in the bowel wall. This could require surgery. Bleeding can also occur after a colonoscopy. Usually the bleeding is minor, but if you experience a large amount of rectal bleeding after your procedure, you must call your doctor immediately. Occasionally, patients may have an adverse reaction to the anesthesia, or complications due to existing heart or lung disease.
Colonoscopies are known for being very safe, but it is still essential to know the warning signs of possible complications. In the event of severe abdominal pain, fever, chills, or rectal bleeding, contact the center or physician immediately. It is possible for bleeding to occur several days after the procedure. Any concerns should be addressed as soon as possible in order to treat any early signs of issues as a direct result of the procedure.