Okay, everyone. Welcome back. Now we're going to build off of some of the lessons we learned this morning. We're going to move to discussions around quality at the patient and unit levels. So to start off our next set of lectures, we're going to welcome back Dr. Jason Dominance to address optimizing bowel preparation in your endoscopy unit. So Jason, the floor is yours. Thank you, Doctors Deloy and Chimpe for inviting me today. You know, we can't do high quality colonoscopy if we can't see the bowel mucosa. So over the next 20 minutes, I'm going to give you some tips on how we can optimize colonoscopy bowel preparation. I have no disclosures. During the talk today, I'm going to review some of the barriers to adequate bowel preparation and then describe approaches to optimizing bowel prep. I will encourage you to adopt either split-dose or same-day bowel preps. And finally, I'll review some bowel prep quality scoring options. We've come a long way in how we prep the bowel over the years, but there are still days when we see something like this when we start our colonoscopy, and we obviously want to avoid this situation. It's bad for the patient to have to come back for another procedure, and it's bad for the physicians and other staff members. It's important to keep in mind that bowel preparation includes not only the laxative, but also the timing of the laxative and dietary changes, medication adjustments such as insulin, the mental and physical preparation of the patient, such as what to expect, and some people will prescribe Vaseline to apply to the anus to reduce irritation. There's also the logistical preparation, having an escort who to call with questions during the bowel preparation. If any of these break down, then the bowel prep may not be adequate. There are many consequences of an inadequate bowel preparation, including a prolonged procedure time, decreased sequel intubation rates, the need to repeat the colonoscopy, which of course introduces extra risk and cost for the patient and decreases the overall experience for the patient and provider alike, and of course, it reduces the chance of detecting adenomas and other pathology during that colonoscopy. You know, it just makes sense, and we know from prior studies that the better the prep, the more polyps you'll find. This study shows that we tend to miss lesions that are under a centimeter in size, but it's still possible to miss larger lesions when bowel prep is less than adequate. We know even with a perfect bowel preparation, we can miss pathology, but the bowel prep certainly can make a difference. Risk factors for a poor bowel preparation are listed on the slide, including older age, male sex, higher BMI, inpatients, polypharmacy, variety of medications such as tricyclic antidepressants and narcotics, and various comorbidities like diabetes, neurologic conditions such as stroke or spinal cord injury, and prior surgical resection. You would think that a patient who's had a partial colectomy would be easier to prep, but in fact, those patients are more likely to have inadequate bowel preparation, likely due to altered innervation of the colon. You'd think after all the years that we've been doing colonoscopy, we'd have a standardized process for this that's used across all facilities, but this is far from the case. In this study of ASG ERP sites, they found that about 20 percent of sites were still using single-dose bowel preps, and there was wide variation in dietary instructions and in medication instructions, including instructions to stop aspirin before colonoscopy, which really should not be done at this time. With regard to patient education, there's been a lot of studies looking at how best to do this, and I think it really helps to standardize your process as much as possible. You should have written materials. Having videos available can also be helpful. There's mixed literature on the role of videos, but some do show benefits. You can outsource education. You can use texting apps, smartphone apps, robocalls to help remind people about their bowel preps. I think we really don't have the ideal patient education process nailed down at this time. So what is the best bowel preparation? Well, we have many purgative options. This slide just outlines some of the major categories. Of course, we have the isoosmotic full-volume preps with four liters of PEG electrolyte solutions like Colite or Golightly. There's the isoosmotic low-volume preps like Muviprep, which is two liters of PEG with ascorbic acid. There's the hyperosmotic low-volume preps like SuPrep, Propopic, Clenpic, SuTab, and OsmoPrep. And then there are over-the-counter products that are used for bowel preparation, including Magsitrate and Miralax. If you want to review the various bowel preparation options in more detail, there's a nice paper from the ASGE, one of our guidelines published in 2015 by Saltzman et al., that outlines each of the available options at that time, their composition, the dosing, whether or not they're FDA-approved, cost, and other details. So take a look at that document for more details than I can provide at this time. We've come to learn that probably the most important aspect of bowel preparation quality is the timing of the administration of the bowel prep. This study looked at the hours between the last dose of bowel prep and the start of colonoscopy, with the shortest interval being eight hours. And they used what's called the Ottawa bowel prep scale. The Ottawa scale has lower numbers for better quality preps. It's different than the Boston score that you may be familiar with. So what you see is that the best scores are obtained when the bowel prep was administered eight hours before colonoscopy, and then the scores get worse as the number of hours increases. This recognition of the importance of timing led to the development of split-dose bowel preps. In a split-dose prep, part of the purgative is taken the evening prior to colonoscopy, usually about half. The second dose ideally starts four to six hours before colonoscopy, and should be completed at least two hours before the procedure time, based on NPO requirements for sedation. This type of prep has demonstrated superiority over day-prior preparation. In a meta-analysis of many studies comparing split-dose PEG to day-prior full-dose PEG, they found that split-dose was associated with much more likelihood of having an adequate bowel prep. The odds ratio was 3.7. Patients were also less likely to discontinue the prep, more willing to repeat the prep, and had less nausea. So not only does it do a better job of cleaning the colon, but patients prefer it. When you look at adenoma detection for day-prior versus split-dose bowel preparation, we see in these four studies of over 1,200 patients that there was a significant benefit favoring split-dose prep. You can see here that the relative risk or risk ratio was increased by 26%. Now, how about low-volume split-dose preps compared to high-volume split-dose preps, for example, 4 liters versus 2 liters? You can see on this slide that there are many, many studies. The upper segment of the slide is looking at low-volume PEG studies, and there's about 6,000 patients in those studies, and you can see that there is no difference. The risk ratio is 0.99. No difference between those two options, between low-volume and high-volume. And then in the lower part of the slide, they're looking at lower-volume non-PEG bowel preparations compared to high-volume, and here the risk ratio is 1.0. So again, no difference. So as long as you're splitting the prep, it didn't matter if it was low-volume or high-volume. I think there's a caveat to most of these studies in that they tend to choose relatively healthy patients to be in these studies. They tend to exclude people who might be at higher risk for having inadequate bowel preparation in many of these studies. Given all the high-quality evidence we have supporting split-dose bowel prep, why isn't this universally adopted? Well, one argument brought forth is that patients are unwilling to get up early in the morning for that second dose. Actually, surveys show that the vast majority of patients are willing to get up early in the morning, and I think if we appropriately educate patients about the importance and the benefits of split-dosing, that most will agree to do this. Some patients are worried that taking a dose in the morning and then getting in a car and driving sometimes hours to the end of the appointment will mean that they'll have a risk of having incontinence or urgency while they're en route, and I understand this concern. There are actually studies that have looked at this and found no difference between patients undergoing split-dose versus night prior dosing. The other argument brought forward is that some anesthesiologists want to have six or even eight hours of NPO status before doing colonoscopy. This is something that we need to work on educating the anesthesiologists about. If you look at their guidelines, the American Society for Anesthesiology says that clear liquids should have a minimum fasting period of two hours, and the last time I looked, the bowel preparations are a clear liquid. Some anesthesiologists are concerned about aspiration of this solution because it may cause a significant aspiration pneumonia because it could be hyperosmotic. In a study from Doug Rex's group, they looked at the mean residual gastric volume after split-dose preps versus evening prior preps, and as you see in the lower half of the slide, the mean residual gastric volume was no different between split-dose prep or evening prior prep. What they did was they did EGD and aspirated out all the liquid that they could find in the stomach. Liquids empty from the stomach quite quickly in the vast majority of patients. There are always exceptions, but the vast majority of patients empty extremely quickly, so this should not be a barrier to split-dose preps. Another option to consider is same-day bowel preparation, especially for afternoon cases. Given what I told you about the importance of the timing, could you not drink the full four liters, for example, of Colite or Golightly at six in the morning and finish it several hours before an afternoon case? There are studies that have looked at this, and one of the advantages is that patients are less likely to lose sleep or have bloating compared to the evening doses or split-dose schedule, and there's less interference with their work schedule. They just have to get up early in the morning, start drinking the bowel prep. The day prior can be a relatively normal day. In this study, you see in red patients who had four liters of PEG the night before, and in yellow, four liters of PEG on the morning of, and again, using the Ottawa score, they see that the percentage of patients with a good score is much higher when the prep was administered in the morning for afternoon colonoscopies. If you look at this meta-analysis of about 1,600 patients undergoing either same-day prep versus split-dose prep, we see no difference in adenoma detection rates. So they're equivalent for adenoma detection rates. From my perspective, this means it becomes a patient preference issue. If patients would rather drink the whole thing in the morning and not have to worry about feeling like they're going to have diarrhea when they're trying to sleep, this is a nice option. Let's move on to dietary restriction. Is it necessary to put people on a clear liquid diet for the day before a colonoscopy? Well, there are studies that have allowed low-residue diets for breakfast and lunch, and some studies even dinner, and they found no difference in prep quality when compared to a clear liquid diet. This improves the tolerability of the bowel preparation, and patients are more willing to repeat the prep for future colonoscopies, which is important, as many of our patients require surveillance down the road or repeat screening in several years. The U.S. Multi-Society Task Force says if you're using a split dose, you can allow a low-residue diet or full liquids until the evening prior to colonoscopy. This meta-analysis shows the results of many studies, about 3,000 patients, and you can see that the overall study has no significant difference, maybe a slight benefit toward a low-residue diet. And don't forget that even when the bowel prep is less than optimal, we do have the water jets on our scopes that can help us clean the bowel during the colonoscopy. So I wanted to review the U.S. Multi-Society Task Force recommendations. These were published by Johnson et al. in 2015, and I'll just go through these quickly, but I strongly urge you to read the Johnson paper, at least scan through it to see the key points that apply to you and your practice. So first of all, the choice of prep should be individualized. Split dose preps offer a high quality of bowel cleansing, and so the USMSTF recommends either split dose or same-day prep, as I discussed. The last dose should begin four to six hours prior to the start time and finish no less than two hours prior to colonoscopy. A low-residue or full liquid diet on the day prior to colonoscopy is recommended. And in healthy, non-constipated individuals, four liters of PEG produces a quality of bowel preparation that is not superior to lower-volume PEG formulations. We don't really know if the low volumes work as well in those higher-risk groups. Use caution with over-the-counter regimens, especially when prescribing bowel preparation for patients with chronic kidney disease. You should avoid sodium phosphate preps in the elderly or in suspected IBD or in children less than 12. While routine use of adjunctive agents is not recommended, it should be considered in patients at risk for inadequate bowel preparation. In patients who have had bariatric surgery, use of a low-volume prep or extended time to ingest the prep can be helpful. For pregnant women, use tap water enemas for sigmoidoscopy. We generally avoid colonoscopy in pregnant women. And then provide oral and written instructions to the patient, ideally in their primary language. If the bowel prep is inadequate in the rectal sigmoid, you should abort and try additional prep. Sometimes this can be done in the procedure unit. If the patient hasn't been sedated too much, you can put them over recovery, give them additional bowel prep, and maybe bring them back to the procedure room later in the day to avoid another trip to the endoscopy unit. You lose out on some patients who go home and decide never to come back, and we all worry about missing pathology. If the bowel prep is inadequate, you can also attempt large-volume enemas. Some places will give bowel preparation through the scope or give additional oral cathartics, as I talked about. In the end, if you don't have an adequate bowel preparation, then you should repeat the colonoscopy within one year and typically prescribe a more aggressive bowel prep unless the patient was not adherent with the initial bowel prep. If the bowel preparation is adequate and complete, then you should follow the surveillance guidelines. And overall, physicians should assure that appropriate support and process measures are in place to assure that their patients get adequate bowel preparation. So if you're finding inadequate bowel prep on a lot of your patients, you need to take a step back and look at what are you prescribing, how are you educating the patients, figure out what you can do to make the process better. The U.S. Multisociety Task Force recommends that the frequency with which bowel preparation is adequate to allow the use of recommended surveillance or screening intervals be measured, and that you should have at least 85% of your patients, that is your outpatients, having an adequate bowel preparation. The greeting of the bowel prep should only be done after you've done all your cleaning of the debris. So after you've done your washing and suctioning, that's when you score the bowel prep. It doesn't matter if it's suboptimal before you washed, all that matters is how it looks at the end of the day. I mean, you can document how it looked when you started, but really when you're looking at your overall adequacy, it's how does it look when you're done with your procedure. And you should routinely measure that, as I said, and if it's not 85% adequate on a per physician basis, then something needs to be done. Adequacy is now defined as a bowel prep that is good enough that the physician is comfortable recommending the standard screening or surveillance interval. We no longer use the definition of confidence that polyps over five millimeters in size were not obscured. And I strongly suggest that we use the Boston bowel prep scale for our scoring. It's the best validated scoring system. I'll also talk about the Orontix scale, although this has not really been validated. Here you see the definitions of the Boston bowel prep scoring. It's a score of zero to three for each of three segments of the bowel. And you can see the definitions here of how much stool is visible in each of those segments. This slide has the link to a free training video. You assign a score for each of the three segments, right, transverse, and left colon. So the best score possible is nine. When the Boston score is at least two in each of the three segments, then we should feel confident that we have an adequate bowel preparation. In a really nice study by Clark and Lane, they found that when the segment score was two, the miss rate for adenomas over five millimeters in size was only 5%, whereas the segment score of one had a 16% miss rate. So if you see a score of at least two in each of the three segments, you should feel confident that the bowel prep was adequate. Here we see the Orontix scoring system, which a lot of people use. It's poor, fair, good, or excellent. Unfortunately, this system has really never been validated, and I don't think really people know exactly how to apply this. It's very subjective. Let's wrap up with the Multi-Society Task Force recommendations on bowel prep scoring. They emphasize that scoring should be done after all cleaning is completed, and you should routinely be assessing the adequacy of the bowel prep. And again, if you're not seeing 85% adequacy on a per physician basis, then you should be doing something to try to improve those rates. Finally, our take-home points. First and foremost, use a split-dose bowel prep. For afternoon cases, use of a same-day bowel preparation can be quite helpful. It gets high-quality exams, and patients often prefer that. Patients often prefer to eat, and evidence shows that you can liberalize the diet on the day prior to colonoscopy and allow a low-residue diet as long as you're using a split-dose bowel prep. We should be grading the bowel preparation, ideally with a validated scoring system for each colonoscopy, and then the practice should monitor bowel prep adequacy on a per physician basis. If you're not seeing at least 85% adequate, then you should be implementing quality improvement processes and monitor the effects of that change. And finally, I've got a couple of key references for you, the Multisite Task Force and the ASGE guidelines on bowel prep. Thanks for your attention. We can discuss any questions or comments during the roundtable.

bowel preparation

colonoscopies

split-dose bowel preps

inadequate bowel preparation

isoosmotic full-volume preps

patient education