We hope the following questions help you to get some preliminary answers. Of course, we are happy to talk to you and see you in the office. There is no replacement for a face to face discussion. That’s why we are here!
- What is gastroenterology?
- What is a gastroenterologist?
- What does a gastroenterologist do?
- What other organs do gastroenterologists deal with?
- What does it mean to be board certified?
- Why might I need a gastroenterologist?
- What type of anesthesia is used for procedures?
- Wait, isn’t propofol what Michael Jackson had?
- What is an EGD, or upper endoscopy?
- What are reasons people might need an EGD?
- What causes ulcers?
- What are GERD, reflux, and heartburn?
- What is eosinophilic esophagitis?
- How is an EGD useful in the diagnosis of diarrhea?
- What’s the deal with gluten?
- What is a colonoscopy?
- What are reasons people might need a colonoscopy?
- What are polyps?
- What are “flat polyps”?
- What is the likelihood of finding a polyp on my exam?
- What are adenomas, sessile serrated polyps, and hyperplastic polyps?
- What is colitis?
- What are the symptoms of colitis?
- What is diverticulitis?
- What is diverticulosis?
- What is the difference between diverticulosis and diverticulitis?
- Do I need to avoid seeds and nuts if I have diverticulosis?
- What is ischemic colitis?
- What is infectious colitis?
- What is ulcerative colitis?
- What is Crohn’s Disease?
- What is microscopic colitis?
- When am I due for colonoscopy?
- What is the difference between a “screening” and “diagnostic” exam?
- Do I need to hold my blood thinner before a procedure?
- What is a “clear liquid diet”?
- What does it mean to try to achieve “clear stools”?
- How close to the procedure can I eat or drink anything?
- What if I throw up drinking the prep?
- What if I can’t drink the whole prep or it doesn’t work?
- What if I had the test before and could not drink the whole thing?
- What if I had the test before and I wasn’t clean enough?
- If I am a small person, do I need to drink the same amount of prep?
- What if I don’t eat anything for several days before the test?
- What if I have the test, and I’m not clean enough?
- Are the preps safe?
- Can I take a preparation using just pills?
- What’s with all the prep questions??
- What if I have specific medical issues, such as diabetes, hypertension, or sleep apnea?
- Do you take credit cards?
- What kind of charges are to be expected?
- My insurance does not cover the bowel prep, even though they cover the colonoscopy. Why is that?
- Is there a consult or history and physical charge as well as the procedure?
- Where are the procedures done?
- Why do I need someone to get me if I feel I can walk, take the train, or take a cab?
- When can I resume normal activities after my procedure?
- Is it OK to have a colonoscopy while on my menstrual period?
- Do I need to take antibiotics if I take them for other procedures?
- How in the world did you get into this field?
- What about infection control during procedures?
Q: What is gastroenterology?A:
Gastroenterology is the medical specialty that deals with issues related to the digestive tract. It is frequently abbreviated “GI”. Even healthy people need periodic, if infrequent, input of a gastroenterologist to maintain their overall health.
Q: What is a gastroenterologist?A:
A gastroenterologist is a medical specialist that can help you with digestive issues and perform endoscopic examinations of your GI tract. Training consists of a four year undergraduate degree, four years of medical school, three years of internal medicine residency, plus several additional years of gastroenterology fellowship. Each level of training represents further subspecialization and expertise in a field.
Q: What does a gastroenterologist do?A:
A gastroenterologist can provide consultative services, manage digestive diseases in a long-term fashion, and performs procedures such as upper endoscopy and colonoscopy.
Q: What other organs do gastroenterologists deal with?A:
We frequently deal with disorders of the liver, gallbladder, pancreas, and various symptoms such as nausea, loss of appetite, and nutritional deficiencies.
Q: What does it mean to be board certified?A:
A board certified physician has demonstrated excellence in their field, as evaluated by a standard examination completed upon graduation from fellowship. An ongoing program of continuing medical education and re-examination is required to maintain board certification. This helps to ensure your physician is up to date in an ever-changing field.
Q: Why might I need a gastroenterologist?A:
You might seek out a gastroenterologist to address specific symptoms, or as a matter of routine. A gastroenterologist can help review your history, your symptoms, and physical findings to help point towards a diagnosis. You might need a gastroenterologist to manage a known diagnosis outside the expertise of your primary physician. Gastroenterologists perform upper endoscopy and colonoscopy as routine preventative services, to address specific symptoms, to confirm suspected diagnoses, and to evaluate progress when specific issues are found.
Q: What type of anesthesia is used for procedures?A:
At Endoscopy Center of the North Shore, all endoscopic procedures are performed with modified anesthesia care (MAC). Services are provided by Mobile Anesthesiologists of Chicago. Sedation can be provided by any number of drugs, but the most common is propofol. This is a safe and effective anesthetic when used appropriately. It is short acting, and does not cause the loss of memory and drowsiness you may have experienced in the past. See here for more http://zzzmd.com/patients/
Q: Wait, isn’t propofol what Michael Jackson had?A:
Yes, but when used in the appropriate setting this is an excellent medication. Outpatient endoscopic procedures are exactly the type of situation that this sedative was designed for. It was not designed for being used regularly, being able to sleep on demand, as a replacement for normal sleep, or in any type of unmonitored home situation. At Endoscopy Center of the North Shore, it is utilized only with one-on-one direct patient observation directly by your anesthesiologist.
Q: What is an EGD, or upper endoscopy?A:
An upper endoscopy (“EGD”, or esophagogastroduodenoscopy) is an examination through the mouth, down the esophagus, through the stomach, and into the duodenum. The duodenum is the first part of the small intestine, and is just past the stomach. Collectively, these parts are known as the “upper GI tract”. The procedure uses a thin, flexible scope. Biopsies can be obtained through the device. The patient is generally sedated for the procedure, and is completely unaware of the events. There is no preparation needed, other than fasting.
Q: What are reasons people might need an EGD?A:
An upper endoscopy can be performed to address specific throat issues (for example, those suspected to be related to reflux), heartburn, difficulty swallowing, atypical chest pain, abdominal pain, dyspepsia, bleeding or blood in the stool, anemia, and sometimes diarrhea.
Q: What causes ulcers?A:
It used to be felt that stress and diet caused ulcers. While these may play some role, most ulcers are due to either bacteria in the stomach (H. pylori) or aspirin-like medications (NSAID’s).
Q: What are GERD, reflux, and heartburn?A:
These are all related terms. Heartburn is the main symptom of acid reflux. Gastroesophageal reflux disease (GERD) is the technical name. Symptoms can vary beyond heartburn, and include throat discomfort (laryngopharyngeal reflux disease, or LPRD) or difficulty swallowing. Longstanding reflux can lead to strictures (narrowing of the esophagus) or Barrett’s esophagus (a precancerous condition).
Q: What is eosinophilic esophagitis?A:
Certain individuals develop an allergic reaction in the esophagus which can cause difficulty swallowing or present similarly to reflux. It used to be common only in young people, but the incidence has risen dramatically in the last decade.
Q: How is an EGD useful in the diagnosis of diarrhea?A:
The small bowel is where you do the majority of absorption of nutrients. We can approach the small bowel easily for a biopsy by performing an upper endoscopy. Celiac sprue, caused by an allergy to gluten, is a common cause of small bowel diarrhea.
Q: What’s the deal with gluten?A:
A lot of attention has been paid to gluten in the past few years, and with good reason. Antibody levels to gluten have risen over the past decades and so have symptoms. Some people are gluten sensitive without true allergy, but others can have a frank allergic issue (celiac disease) with many health implications.
Q: What is a colonoscopy?A:
A colonoscopy is a procedure using a flexible camera passed through the rectum and through the large intestine. The procedure is done as a matter of routine on even healthy people at specific ages and intervals. The patient is generally sedated, and completely unaware of the test. The difficult part of the test is taking the bowel preparation that is required for the physician to be able to see adequately.
Q: What are reasons people might need a colonoscopy?A:
People have colonoscopy as a matter of routine, to remove polyps that might be growing throughout the colon. Polyps are silent, and there is no other way to reliably diagnose and remove them. Polyps have the potential to grow into cancers. By removing the polyps, the risk of colon cancer is dramatically reduced. People also have colonoscopies to address specific medical issues such as anemia, blood in the stool, diarrhea, weight loss, abdominal pain, to follow up issues such as diverticulitis or ischemic bowel, or to evaluate certain radiographic abnormalities.
Q: What are polyps?A:
Polyps are benign growths that occur throughout the lining of the colon. These are the precursor lesions for colon cancer. Polyps are generally benign, and removing them prevents colon cancer from developing.
Q: What are “flat polyps”?A:
Flat polyps are typically harder to find, and therefore are thought of as higher risk. At Endoscopy Center of the North Shore, we utilize high definition cameras and video monitors. Being thorough in finding these lesions is one of the reasons we emphasize the bowel preparation to be as optimal as possible. We inspect all of the visualizable mucosa of the colon. When safe, we will retroflex the scope (turn the scope around to look behind folds) in the right colon, which is where flat polyps tend to occur. We also use narrow band imaging, which is a specific alternative light frequency which highlights flat polyps. All of these help us achieve a very high detection rate for this type of lesion, significantly higher than the national average.
Q: What is the likelihood of finding a polyp on my exam?A:
For men, the likelihood of finding a polyp is reported at 31% for routine exams with no identifiable risk factors. For women, it is approximately 20%. At Endoscopy Center of the North Shore, our results are higher than the national average based on published studies. This speaks to the diligence with which we examine the colon. Issues such as a prior history of polyp or a family history of colon cancer will significantly change the likelihood of having a polyp.
Q: What are adenomas, sessile serrated polyps, and hyperplastic polyps?A:
Adenomas are the type of polyps that have potential to grow into colon cancers. Sessile serrated polyps are “flat polyps” that may be more difficult to find. They may have some potential to become cancerous. Hyperplastic polyps, except in rare instances, are very low risk lesions and are generally thought to be a normal finding. Having had a hyperplastic polyp in the past generally does not put you in a high risk category. The exception is if they are larger, flat polyps in the right side of the colon. In that case, they are more like the sessile serrated polyps.
Q: What is colitis?A:
In its broadest sense, “colitis” simply means inflammation of the colon. This can encompass many causes. Diverticulitis is a form of colitis. Colitis can result from an infection, lack of blood flow, or an immune process such as ulcerative colitis or Crohn’s disease.
Q: What are the symptoms of colitis?A:
Colitis can present with pain, bleeding, weight loss, diarrhea, and other symptoms. The type of symptoms, the duration, and the severity offer important clues as to the cause.
Q: What is diverticulitis?A:
Diverticulitis is an acute condition that results when a diverticulum (a form of pocket or small herniation in the colon) strains to the point that it induces an inflammatory reaction. Bacteria entering the gut lining or even passing through the lining are part of the cause of inflammation. Treatment consists of bowel rest, antibiotics, and sometimes surgery.
Q: What is diverticulosis?A:
Diverticula are small pockets that form in the lining of the colon. The prevailing theory has been that excess pressure from a lack of fiber is the cause. This theory is a largely historical one based on the fact diverticular disease is more common in the West, and Westerners eat less fiber than the rest of the world. However, there are emerging theories that may refute this.
Q: What is the difference between diverticulosis and diverticulitis?A:
Diverticulosis is the underlying condition of having the “pockets” in the colon. Once they form, they are there all the time. Most people have them, actually, by a certain age, and don’t have symptoms. An attack of diverticulitis is an acute, temporary condition. If you have diverticular disease, you always have diverticulosis. You may or may not get diverticulitis and when it resolves, you are left with diverticulosis. The only way to get rid of diverticulosis is to have surgery.
Q: Do I need to avoid seeds and nuts if I have diverticulosis?A:
No. We used to recommend that, but better data over time suggest this is not helpful. In fact, people who consume nuts and seeds have less attacks of diverticulitis than those who don’t.
Q: What is ischemic colitis?A:
Sometimes a situation develops where there is not enough blood flow in the colon. This can be the result of low output of blood from the heart or from poor delivery of blood due to hardening of the arteries in the abdomen. Just as people have heart attacks or strokes due to low blood flow in critical arteries, a person can also have an attack of “ischemic bowel”. The good news is that unlike the other organs, the bowel usually recovers very well and very quickly.
Q: What is infectious colitis?A:
Any type of infection that attacks the colon can cause infectious colitis. Common entities include salmonella, E. coli, campylobacter, and many others. Many causes resolve on their own, like gastroenteritis. Specific organisms need specific treatment.
Q: What is ulcerative colitis?A:
Ulcerative colitis is an immune-mediated condition that results in an inflammatory process of the lining of the colon. It can present with bloody diarrhea, pain, and weight loss. Sometimes it runs in families. Treatment has many forms. Initial medical therapy consists of suppositories, enemas, or pills with a timed release profile to target the colon. Steroids are sometimes used to reverse disease, but this is never a long-term solution. More potent medications include immunomodulators. Still more potent medications exist that block key inflammatory mediators and help arrest disease. Although surgery is considered as the only “cure” it is a choice of last resort. Although you may hear stories from people who needed surgery, the vast majority of people do very well on medication alone.
Q: What is Crohn’s Disease?A:
Crohn’s disease is also an immune mediated inflammatory process. However, it can extend beyond the colon and it can penetrate through the gut lining. It can effect anywhere in the GI tract, but it has a predilection for the end of the small bowel where it meets the colon. It can also present with pain, diarrhea, weight loss, and bleeding. Treatment initially consists of pills with a timed release profile to target the end of the small bowel and colon, or to be dispersed throughout the GI tract. Steroids are sometimes used to reverse disease, but this is never a long-term solution. More potent medications include immunomodulators. Still more potent medications exist that block key inflammatory mediators and help arrest disease. Every step up in therapy brings greater likelihood of success but also carries unique risks. Surgery is a poor option but is sometimes necessary. Both gastroenterologists and surgeons do everything possible to avoid surgery.
Q: What is microscopic colitis?A:
There are indeed forms of colitis that are not obvious on endoscopy, but can be seen on biopsies of the colon. There are two types of microscopic colitis, collagenous colitis and lymphocytic colitis. In collagenous colitis, a normally thin band of connective tissue known as collagen becomes excessively thickened. This creates a barrier to absorption of water and the stools become looser. Lymphocytic colitis is characterized by an infiltration of specific immune cells (lymphocytes) that normally help fight off infection. This immune reaction results in diarrhea as well. These microscopic forms of colitis are only very loosely related to ulcerative colitis or Crohn’s, if at all.
Q: When am I due for colonoscopy?A:
Our office is happy to check for you if you had a previous examination. If you have a family history of colon cancer, we generally start routine screening at age 40. If you are of average risk, we start at age 50. African Americans generally start screening at age 45. If you have ever had a polyp (except for a hyperplastic polyp), the longest you should go between exams is five years. This might also be shorter, based on the exact type of polyps, adequacy of the exam, number of polyps, and other factors.
Q: What is the difference between a “screening” and “diagnostic” exam?A:
A screening exam refers to a colonoscopy being done with no specific symptoms but as a matter of routine, for example to check for polyps. A diagnostic exam is generally being done to evaluate specific issues such as blood in the stool, anemia, or diarrhea. Insurances can be fussy about paying for screening versus diagnostic examinations.
Q: Do I need to hold my blood thinner before a procedure?A:
The reason you need a blood thinner is the key to knowing how important it is to continue this through the colonoscopy period. The reason we like to hold blood thinners, is so that we can remove polyps with less risk of bleeding. However, if your doctor feels strongly you need to stay on your blood thinner, we can certainly proceed even while you are on it. You should discuss this with your primary care physician, but please let us know whether or not you are taking a blood thinner when you arrive for your procedure so we know how aggressively we can approach lesions like polyps.
Q: What is a “clear liquid diet”?A:
This refers to a diet that you can see most all of the way through. Examples would include apple juice, any of the sports drinks, lemonade, clear soup broth, and semisolids made out of clear liquids such as Jell-O, hard candies, and popsicles.
Q: What does it mean to try to achieve “clear stools”?A:
For colonoscopy, the bowel preparation is designed to evacuate the bowel of all solid material. The stool should be clear like water ideally. Sometimes it is yellow, and there can be small flecks of slight stool, and that is generally acceptable.
Q: How close to the procedure can I eat or drink anything?A:
You cannot eat anything solid for at least 8 hours prior to the procedure (for an EGD), and breakfast the day before a colonoscopy. You can have clear liquids (including the prep) up to 4 hours prior to the procedure. You can take an essential oral medication with a small sip of water up to 2 hours before the procedure. Nothing else, not even gum, is allowed before the procedure.
Q: What if I throw up drinking the prep?A:
Generally, we advise taking a break from drinking the prep and letting your stomach settle. You can reattempt to drink the rest of the prep later, or drink an alternative prep such as magnesium citrate. Magnesium citrate is available over-the-counter in a green bottle. If you know you have thrown up in the past, or have a sensitive stomach to this type of thing, we can arrange to give you an anti-nausea medicine if you let us know beforehand.
Q: What if I can’t drink the whole prep or it doesn’t work?A:
Ideally, you would drink the preparation in the time span advised. There is some flushing action related to the timing, so sipping it over a longer period of time may not be as effective. However, we certainly understand that this is difficult process. If you need to compromise and slow it down a little to make it more tolerable, that is usually acceptable. Just make sure you finish the whole thing well before your test. If you are drinking the prep and not getting clear, you should plan on also drinking a bottle of magnesium citrate. This is available over-the-counter in a green glass bottle. You should not have any clear liquids by mouth for four hours prior to the procedure, except if you need to take normal medications with a small sip of water. Do not take anything at all by mouth two hours prior to the procedure.
Q: What if I had the test before and could not drink the whole thing?A:
Let us know ahead of time, and we can review your history and results. There are almost always options available.
Q: What if I had the test before and I wasn’t clean enough?A:
We can design a special program for you, including a combination of preps, extra prep, and a two day prep. Let us know how we can help you.
Q: If I am a small person, do I need to drink the same amount of prep?A:
Unfortunately, yes. The colon is approximately the same size in all individuals, regardless of their body size. It stores about the same amount stool, and will require just as much cleansing.
Q: What if I don’t eat anything for several days before the test?A:
Unfortunately, you still make stool even when you don’t eat. In fact, it gets harder and more difficult to pass.
Q: What if I have the test, and I’m not clean enough?A:
Unfortunately, you will have to repeat the test. Sometimes be will have you drink extra preparation, and come back the next day to take advantage of the head start that you have. Sometimes we will ask that you reschedule on a different day with a different type of prep. In rare cases, if we feel that we have seen the majority of the colon but not all of it, we might reduce the usual follow-up interval to a shorter time span but not one in the immediate future.
Q: Are the preps safe?A:
Yes. There are some types of preparation which have side effects or potential risks. For the traditional preps, the risk is negligible. The main risk is absorption of extra salt, some electrolyte shifts while you are fasting, and dehydration. Keeping well hydrated with clear liquids is the key to avoiding issues. Preps containing phosphasoda are not used at our facility. Phosphasoda has been linked to kidney damage, and even though these are still available over-the-counter, manufacturers are required to label each package with a black box warning from the FDA. While these might have seemed “easier” in the past, it is just not worth the risk.
Q: Can I take a preparation using just pills?A:
No. These contain phosphasoda. See above.
Q: What’s with all the prep questions??A:
To have a successful examination, we need to be able to see as much of the surface area of the colon as possible. The likelihood of achieving a complete exam is directly proportional to how clean you are able to get the colon. Any residual stool reduces the likelihood of seeing all of the surfaces, and increases the chances that a polyp might be missed. This is an important exam, done usually many years apart, and we recognize that this is time intensive on your part. To be able to get the most out of it, you should try to achieve the most adequate preparation possible.
Q: What if I have specific medical issues, such as diabetes, hypertension, or sleep apnea?A:
For diabetics, we will try to schedule your procedure in the morning so you can stay as close to your usual routine as possible. If you are taking insulin, you should adjust this based on a sliding scale the day before while you on a clear liquid diet. Your primary physician can help. Do not take insulin the morning of your procedure, but bring it with you. Also bring your glucometer so we can check your sugar. You should take your antihypertensive medications in the morning with a little bit of water. Make sure this is at least two hours before your scheduled procedure time. Inform the anesthesiologist of all your medical issues, including sleep apnea. You do not need to bring your CPAP machine to the G.I. lab if you use one. If you have concerns beyond these guidelines, you should see your gastroenterologist in the office prior to your procedure to discuss an individualized approach to your health care.
Q: Do you take credit cards?A:
Yes, we do. We can take these over the phone, or swipe in person when you arrive.
Q: What kind of charges are to be expected?A:
It is difficult to predict exactly what kind of charges any individual might expect. A lot has to do with what is found, what tools are used to treat findings like polyps, how complex the overall interaction is, how much insurance covers, if the insurance has a contracted charge with us, and if your deductible is met. Sometimes there are scheduling fees and other charges that are not covered by insurance companies at all. In general, you will be billed separately through the medical practice, the endoscopy center, and the anesthesiologist. In general, the fees are much less in the office given the huge overhead in the hospital setting.
Q: My insurance does not cover the bowel prep, even though they cover the colonoscopy. Why is that?A:
Insurance carriers in Illinois are required by law to cover screening colonoscopy. They are not happy about that. Just recently, they stopped covering the prep by arguing that it is not part of the procedure. We are opposed to this for obvious reasons, and you should be too.
Q: Is there a consult or history and physical charge as well as the procedure?A:
Oftentimes, there is. A physician does not act as a technician, and should not perform an invasive procedure on you without a full history and physical, an assessment of the indications, and an analysis of the risks and benefits. Even if you were just “referred for a procedure” the doctor will still examine you and discuss things with you. Although it may not be obvious, you are under the physician’s care from the time you arrive till the time you are discharged. All of the staff caring for you work under your gastroenterologist’s supervision.
Q: Where are the procedures done?A:
Procedures can be done in our state-of-the-art office facility at the office, or at the hospital. Please make sure you are 100% clear on when and where to show up.
Q: Why do I need someone to get me if I feel I can walk, take the train, or take a cab?A:
Technically, you will be under the influence. This is a liability issue, even if it does not seem like a practical one. An adult you know personally must accompany you out of the G.I. lab and to your home, even if you live close enough to walk or are taking public transportation. Ideally, they will stay with you for the next 24 hours.
Q: When can I resume normal activities after my procedure?A:
You can eat whatever you feel up to when you leave the G.I. lab. There are a number of excellent local restaurants that are within walking distance of our office parking lot. Of course, someone must accompany you and be responsible for you. We advise no alcohol, no driving, no making important decisions, and no exercising until the next day. Take the day off, you have earned it!
Q: Is it OK to have a colonoscopy while on my menstrual period?A:
Yes it is. It is okay to use a tampon during the procedure as well.
Q: Do I need to take antibiotics if I take them for other procedures?A:
Keep in mind that your colon is naturally filled with trillions of bacteria every day, and you do not need to take an antibiotic to have a bowel movement. Your body has developed a very effective barrier via the lining of the colon. Passing a scope through the colon does not release any more bacteria into the bloodstream than pushing stool out. Therefore, antibiotics are not required even if you have joint replacements, need them for dental procedures, or most other usual indications. Although orthopedists commonly request we give antibiotics before hand, there is no literature to support this. If they insist, you should get your prescription directly from them. We will not prescribe it. If you have previously had endocarditis or significant heart valve issues, you should check with your cardiologist on whether or not antibiotics are needed prior to colonoscopy.
Q: How in the world did you get into this field?A:
For each physician, the answer would be different. Dr. Mehta, the Medical Director of Endoscopy Center of the North Shore, has a background in the visual sciences. Before becoming a doctor, he worked for PBS. He was a freelance artist while in college and also worked as a medical illustrator while in medical school. Gastroenterology helped to combine his interests in video and imagery with the desire to work with his hands using complex instruments to help people. Dr. Mehta also points to the strong mentorship he received at Rush Presbyterian St. Luke’s from the gastroenterologists who trained him. Ask him to tell you more!
Q: What about infection control during procedures?A:
The benefits of colonoscopy clearly outweigh all combined risks, or we would not do it. The risk of infections with these procedure is exceedingly low, even during colonoscopy where one would expect to find many bacteria. Remember, your gut is filled with trillions of bacteria at every moment. It is very well adapted to handling routine bacteria, even when biopsies are done or polyps are removed. Still, we take great care to ensure that the risk of infection is minimized.
Each and every scope is of course washed and disinfected in a standard commercial reprocessor. Each use and cleansing cycle is logged permanently, as well as information on whom the instrument was used, who cleaned it, and the standard protocol that was utilized. Cleansing solutions are tested for efficacy between each patient to ensure they are within specifications. Antimicrobial water and solution filters are changed regularly per manufacturer guidelines. We use all disposable accessories, like water bottles for irrigation, the buttons which control the scopes, and the valves through which we pass biopsy instruments. Our move to all-disposable accessories was made even before the local hospitals, and reflects a higher standard than anywhere else. The FDA has recently cautioned about this exact issue. Biopsy and polyp removal devices are totally disposable as well. Even with these protocols in place, we routinely check each scope for potential bacterial residue. We monitor for post-operative infection as part of our quality control policy, and to date have had no infections reported.
During procedures, everyone is gowned and gloved. Nothing touches you that has not been decontaminated or has an appropriate, latex-free barrier. All sheets are changed between patients, of course, and reprocessed by a medical laundry service. The carts are completely wiped down between patients with germicide.
So rest assured. Even though the scope is going into the most contaminated place in our worlds, it is as thoroughly cleansed and monitored as possible!