Colonoscopy Specialist

Blair S. Lewis, MD, PC -  - Gastroenterologist

Blair S. Lewis, MD, PC

Gastroenterologist located in Upper East Side, New York, NY

At his Upper East Side Manhattan practice, Dr. Lewis helps New York City patients understand the causes of bowel symptoms, using state-of-the-art colonoscopy procedures designed to look for signs of colon cancer, inflammatory bowel disease and other diseases that affect the colon, or large intestine.

Colonoscopy Q & A

What happens during a colonoscopy?

During a colonoscopy, you'll lie on your back and a sedative will be provided to help you sleep during the procedure. Once the sedative takes affect, an inert gas will be pumped into your colon to help gently expand it so it can be visualized better. A long, thin, flexible tube called a colonoscope will be inserted through your rectum and into your colon. A tiny camera located on the scope will take video of the inside of your colon and transmit it to a monitor for viewing. If a polyp or other unusual area is identified, special instruments will be used to remove the polyp or take a small sample of tissue (a biopsy) for further evaluation in a lab. Most colonoscopies take about 30 minutes to perform.

How will I feel afterward?

Once the colonoscopy is finished, you'll be moved to a recovery area for a brief period of time to allow the sedation to wear off. Although most of the air used to expand the colon will be removed during the procedure, you may feel some bloating until the remaining air is expelled. You'll be able to leave about 30 minutes after your colonoscopy, and you won't have any dietary restrictions. However, because of the sedation, you'll have to have someone drive you home. You'll also need to avoid alcohol for eight hours following your procedure.

What do I need to do to prepare for a colonoscopy?

The day before your procedure, you'll need to drink a liquid or take some pills to clear your bowels. Once you begin your preparation, you'll want to plan on staying home near your bathroom. Your diet will also be restricted to clear fluids during your “prep” period to ensure your colon stays clear so the lining is easily visible. You will not need to have an enema.

Understanding Colonoscopy

Your primary physician has determined that colonoscopy is necessary for further evaluation or treatment of your condition. This brochure has been prepared to help you understand the procedure. It includes answers to questions patients most frequently ask. Please read it carefully. If you have additional questions, please feel free to call our office. To paraphrase a New York retailer, a well-informed patient is our best customer. We strive to provide individual care in a non-rushed, but efficient manner. We have great respect for our patients and make colonoscopy a “non-event.” There is nothing embarrassing about colonoscopy and its proper performance can have a dramatic effect on your life.

What is the colon?

The colon, also called the large intestine, is a six-foot long organ that works to absorb water from the intestinal tract and help store and then deliver bowel movements. Ingested food first traverses the stomach where it is solubilized. Liquefied food then moves to the small intestine and this portion of the intestinal tract acts to absorb nutrients. Fluids then proceed to the colon where stool is solidified as water is absorbed. The beginning of the colon is located in the right lower portion of the abdomen. It comes up the right side and crosses the abdomen under the diaphragm and then drops down the left side of the abdomen into the pelvis and the rectum.

What is colonoscopy?

During colonoscopy, a flexible instrument is inserted into the rectum and is advanced throughout the colon. The patient is lying on their left side during the exam. The instrument has a video camera built into its tip and the image of the lining of the colon is projected to a television screen. The instrument is the diameter of an index finger. Dr. Lewis uses state-of-the-art equipment and presently uses high definition endoscopes. The procedure generally takes 20-30 minutes to perform. Occasionally procedures take longer especially if polyps are encountered. During colonoscopy, biopsies can be obtained from anything abnormal and polyps can be removed. This is all done during the same exam.

What diseases can be detected by colonoscopy?

The colon is the site of the second most common cancer killer in America. The small intestine is an unusual site for cancer. Most colon cancer begins in benign growths called polyps. These bits of tissue can grow over years and then degenerate into cancer. Most polyps are easily removed during colonoscopy, thus reducing the future risk of cancer.

Other diseases that affect the colon include infections or chronic inflammatory illnesses that produce diarrhea, broken blood vessels that can cause bleeding and diverticular disease that in a minority of patients can lead to pain, infection or bleeding. Hemorrhoids can also be seen and assessed during colonoscopy, though surgical treatment requires the intervention of a proctologist and thus is not performed during colonoscopy.

What are other examinations of the colon?

Another way to examine part of the colon is sigmoidoscopy. In this exam, a shorter instrument examines the bottom most portion of the colon called the sigmoid and that is how the exam got its name. This exam requires a less extensive preparation and patients are not usually sedated for the exam.

A newer exam is virtual colonoscopy. In this exam, the same preparation for standard colonoscopy is required. A patient has a small tube inserted in the rectum and air is instilled. A CAT scan is then performed. The pictures obtained can be similar to pictures at colonoscopy. This exam does not allow biopsying of tissue. Polyps cannot be removed and if they are found, standard colonoscopy is required.

Is colonoscopy painful?

Colonoscopy is usually well tolerated and rarely causes pain. The lining of the colon can only sense distention. Unlike the nerves in your hand, there are no nerve endings in the colon that can sense temperature, touch, or pain. Air is instilled during colonoscopy to distend the bowel and allow adequate examination. This can produce the sensation of abdominal pressure. The air is removed prior to the completion of the exam. Patients are sedated prior to starting the exam. An anesthesiologist will administer sedation. The typical drug is propofol. There is no standard dose of sedation and the amounts given are individualized. More medication can always be given during the exam should you become uncomfortable. The medication can produce amnesia and you may not remember the exam.

What preparation is required?

The colon must be completely clean for the procedure to be accurate and complete. A liquid diet for part of the day prior to the exam is required followed by an oral purgative that cleanses the colon. Enemas are not necessary. The office will provide you with detailed instructions for the preparation in separate literature. The preparation will vary according to your medical history and the timing of your exam.

What should I do about my current medications?

Most medications may be continued, but some medications can interfere with the preparation or the examination. Blood thinners, insulin and iron products are examples of such medications. You should notify the office of all medications that you take as well as any medication allergies you have. You should alert the office if you require antibiotics prior to undergoing dental procedures, since you may need antibiotics prior to colonoscopy as well.

What happens after colonoscopy?

You will rest following the completion of the exam. Generally, patients are able to leave the office 20 to 30 minutes after the exam. You will be able to leave under your own power. You will be able to eat immediately after the exam and food will help you eliminate any remaining effects of the sedation medications. There will not be any dietary restrictions. You cannot drive a car for 8 hours or drink alcohol for 8 hours after the examination.

Will I find out the results of the exam?

Dr. Lewis will meet with you after the exam and results will be provided immediately. Results of any tissue sent for pathologic evaluation are usually available after 3 business days. Our office will call you in several days to make sure you are well and provide the opportunity to ask any remaining questions. A full written report will be sent to your physician.

What are the possible complications of colonoscopy?

Colonoscopy and polypectomy are extremely safe. Possible complications include bleeding from a polypectomy site and perforation of the colon wall. Bleeding is usually minor and stops on its’ own or can be controlled through the colonoscope. Only rarely are blood transfusions or surgery required. Perforation is extremely uncommon during a normal exam and when it does rarely happen, it is usually associated with attempts to remove large polyps or tumors. Perforation requires immediate surgery.

Although complications after colonoscopy are uncommon, it is important that you recognize early signs of any possible complication. Notify the office if you have severe abdominal pain, fever and chills, or rectal bleeding of more than one-half cup. Bleeding can occur several days after polypectomy.

How are instruments cleaned?

There are specific federal guidelines for cleaning endoscopic equipment. The endoscopy center closely adheres to all of these guidelines. All equipment is manually scrubbed and then placed in an automatic disinfection unit. All instruments are tracked and spot-checked for contamination.

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The Complex Colon

Occasionally, individuals will have incomplete exams when they go for screening colonoscopy. The entire colon is not traversed and examined. This can occur due to the presence of severe diverticular disease, adhesions from previous surgery or congenital malformations such as situs inversus. Dr. Lewis specializes in the difficult colonoscopy and is able to reach the beginning of the colon, the cecum, in more than 99% of exams. He has a variety of instruments available that are longer, thinner or have the right stiffness to allow a complete exam. Many patients are referred to him after incomplete colonoscopies performed elsewhere and he completes their exam in virtually every case.

Major Insurance Providers Accepted

If you have any questions, please contact our office.

Blue Cross Blue Shield
Empire Blue Cross Blue Shield
Horizon Blue Cross Blue Shield of New Jersey
Horizon NJ Health
Multiplan PHCS
Multiplan, Inc.
Oscar Health Insurance Co.
Oxford (UnitedHealthcare)
Oxford Health Plans