Liver Specialists of Texas: Procedures We Perform: Colonoscopy
As a Hepatologist (liver specialist) and Gastroenterologist, Dr. Galati is trained to perform a wide range of procedures.
Colonoscopy is an endoscopic procedure that enables a physician to examine the inner lining of your colon (large intestine) for abnormalities by inserting a flexible tube, approximately as thick as your finger, into your anus and slowly advancing it into the rectum and colon. Colonoscopy is indicated for a large number of problems that commonly include, but are not limited to chronic abdominal pain, screening for colon cancer, diarrhea, weight loss, colitis, blood in the stool, a prior abnormal barium enema, constipation, a personal history of colonic polyps, or a family history of colon cancer.
As of 2019, it is recommended that screening for colon cancer starts at age 45, not the previously recommended 50 years old. Remember, screening is designed for those individuals that are free of symptoms. If you have symptoms, you still need further investigations, but this would considered more of a diagnostic procedure.
Prior to performing colonoscopy, the colon needs thorough cleansing so that there can be unobstructed view of the entire colon. Depending of the bowel preparation selected for you, you will need to be placed on clear liquids for one to two days prior to the procedure. This will increase the effectiveness of the bowel preparation. Similar to other procedures we perform, you will need to remain NPO after midnight. In most cases, you will be instructed not take your morning medications. Diabetic patients will need to receive special instructions on their insulin dosing prior to the procedure.
It is very important that the instructions for the bowel preparation are followed exactly as printed. If you have questions, ask our staff immediately. Here is a video of what a poor bowel preparation lookes like.
Upon arrival to the outpatient and patient registration areas, you will be taken to the “pre-op” area, where you’ll be greeted by a nurse, who will review your medical history, medications, and questions you may have prior the procedure. The nurse will also review the informed consent for the procedure you will need to sign. Because anesthesia will be used, a small intravenous catheter will be placed.
You will be moved on stretcher to the procedure room, where you will continue to be monitored. Your blood pressure, heart rate, oxygen saturation, and respiratory status will be monitored continuously. Dr. Galati will be working side by side with a Nurse Anesthetist will administer anesthesia, consisting of propofol. This medication has a quick onset of action, and patients wake up much quicker when the procedure is completed. If you have a prior allergy to these medications, other similar medications will be substituted.
Before beginning the colonoscopy, the nursing staff will properly position you on your left side. Dr. Galati will start giving you an appropriate amount of intravenous medication for sedation and comfort. A digital exam to will be performed to check for anorectal pathology and prostate abnormalities in men. Following this, a liberally lubricated instrument is pressed into the anal canal until the sphincter relaxes. Once the rectum is entered the colonoscope is advanced toward the lumen by angling and rotating the tip by using the horizontal and vertical controls and applying torque to the shaft of the scope. By applying a variety of maneuvers with the help of the nursing staff, experienced endoscopists are able to advance the scope from the rectum to the cecum in approximately 90-95% of procedures. It is also possible to extend the examination through the ileocecal valve and examine the distal terminal ileum in many cases.
The procedure lasts between 15-20 minutes. Following the procedure the patient is observed while the effects of analgesia and sedation resolve.
During the procedure, in addition to visualizing the entire length of the colon, abnormal areas of the mucosa can be biopsies. Polyps, which are abnormal growths in the colon, can be removed and sent to the lab for analysis. It is generally accepted that these polyps have the potential to transform into colon cancer. They can occur in several locations in the gastrointestinal tract but are most common in the colon. They vary in size from less than a quarter of an inch to several inches in diameter. They look like small bumps growing from the lining of the bowel and protruding into the lumen (bowel cavity). They sometimes grow on a “stalk” and look like mushrooms. Many patients have several polyps scattered in different parts of the colon. Other abnormal areas of the colon can be biopsied directly through the scope and sent for laboratory analysis. Area of bleeding, if present, can also be controlled by using additional instruments that can be inserted through the instrument and used under direct visualization.
The most serious complication of diagnostic colonoscopy is perforation (tear of the bowel) which has been reported in 0.14-0.25% of cases. Perforations may be caused by pressure exerted at the instrument tip or by a loop formed along the shaft of the instrument, or by a rupture of a diverticulum. Bleeding during colonoscopy, even after biopsy, is extremely rare, but has been reported after polyp removal in 0.7-2.5% of cases. Other more common, but usually less serious complications include medication reactions, bacteremia, and post-colonoscopy distention (excessive air in the bowel). Deaths as a result of colonoscopy are reported in less than 0.02% of reported large series.