Annette Bisanz, MPH, RN
Advanced Practice Nurse
Nursing Administration
The University of Texas, M.D. Anderson Cancer Center
Hello. My name is Annette Bisanz and today we are going to talk about an overview of factors influencing bowel function.
Our objectives are that all participants will be able to discuss and teach others about the role of food, fiber, fluid, and medication in bowel management. Also you will be able to suggest how to relieve gas symptoms and discuss Ogilvie's Syndrome and how to treat it.
Patient teaching is the key to promoting bowel function.
Important ingredients for the bowel to function properly are food, fluid, fiber, and medication.
Let's start with food. The quantity of food affects GI transit. Whenever you eat a large meal, the food has a normal peristaltic pushdown in the gut to make room for the new food coming in. The frequency also affects GI transit, and so if you are eating small, frequent meals, you are not having the massive peristaltic pushdown that you would if you were eating a big meal. The types of food that affect each --the types of food that you eat affect each person differently. For example, if I gave each of you four prunes when you came in here this morning, and probably before the class was over, somebody might have to go and have a bowel movement, and others may have a bowel movement this evening, and some people it may not affect at all. So the types of food then does affect each person differently. There is a value to taking a food history and stooling pattern because then you can always look back and say, "Oh look, every time I eat this particular food, I have this reaction."
Let's talk about the role of fluid in bowel management. The daily requirements of fluid for the average adult is 2 quarts or 64 ounces. It seems that the temperature of the fluid does make a difference. You hear people say, "Every time I have my coffee in the morning, I am off to the restroom." Well, it does not seem to be necessarily the coffee, because people who drink hot tea, exactly the same thing happens. With cold fluid, it does not seem to have an effect on the GI tract one way or another. This is a clinical observation. The action of fluid with fiber is also important for you to understand. The amount of fluid that you take with fiber does influence the GI motility, and so if you drink more fluid, it will increase the GI motility, and if you drink less fluid, it will slow down the GI motility. Fluids with meals versus in between meals does have an effect. If you tend to be having constipation, I would recommend taking a lot of fluid with your meals. However, if you tend to have diarrhea, you may want to refrain from over-taking fluids. Don't take more than 8 ounces with your meals, and I think you will find that you will have less stooling after the meals.
Fiber is very important in bowel management. Daily requirements are 25 to 40 grams per day. The average American only gets about 10 grams. This is not enough. Nutritional versus medicinal fiber also needs to be considered. If a person is not taking enough fiber, what we want to do is make sure that we give it to them therapeutically through medicinal fiber. There are different types of fiber. There is soluble fiber which causes a fermentation process in the GI tract and helps to push stool down that way, and this is the result of taking certain fruits and vegetables. There is also bulk-forming fiber, and this is in the form of bran and cereals that we take, and wheat breads, and this is very important and serves a particular purpose in increasing or decreasing the GI motility.
So the effects of fiber, then, on the GI tract are replenishing the bacteria in the colon to increase water content in the stool, affecting the consistency of stool and helping it to remain soft. It also can increase fecal bulk. It increases or decreases transit time, and it can affect the intraluminary pressure and keep the villi within the colon very, very healthy.
Bulk-forming fibers tend to regulate the increase or decrease of GI transit, and when we are talking about that, medicinally, we are talking about Metamucil® or Citrucel®.
Note the contrasting ways of using fiber for constipation versus diarrhea or frequent stooling. For constipation, it is important to take one tablespoon of psyllium or Metamucil or one tablespoon of Citrucel®in eight ounces of water and immediately follow it with eight more ounces of water. If you have frequent stooling, it has been found that taking a smaller amount of fiber, like 3.4 grams of psyllium or Metamucil® in 2 ounces of water after a meal will form like a food bolus with the food and slow everything down. People are encouraged not to drink any fluid for one hour afterwards, and this will slow down the GI motility. This is very effective in our patients who have had GI surgery and have frequent stooling after a colorectal resection.
In your experience, do patients like to take fiber? Isn't it human nature to take the easy way out? And one of the things that is on the market right now is fiber capsules and caplets. And I have heard people say "Well gee, you know, I was taking the Metamucil® in powder form, and it was working very well, and I was taking it with 8 ounces of water, following it with 8 ounces of water, and then I switched to the fiber capsules. And it told me that I needed to take 5 capsules to equal the one tablespoon, but after I took it, I found I drank the same amount of water, but I found I became constipated." The reason is, when those capsules break down (or caplets), the fluid that you took in, perhaps, may be long gone, and then your fiber is going to cause the other phenomenon of slowing down the GI motility. So don't take the easy way out, please stick with your medicinal powdered fiber. It works in a very excellent way for your GI tract.
There is confusion in the marketplace. Advertisements really don't give the full story. You have probably seen the advertisement where Grandpa is chugging his Metamucil® and the grandson comes along and says "Oh Mommy doesn't chug hers, she just puts it into a glass of water and drinks it down slowly." Well the thing is, Mommy and Grandpa are not taking the same thing. Mommy's taking a soluble fiber and Grandpa is taking a bulk-forming fiber. And so patients need to know, what is the difference between the bulk-forming and the soluble? And when they are buying things over the counter, that they are getting what they need for their own health. Make sure the patient knows what is needed for their particular problem. Also compare gram dosages from one form to another. For example, if you buy a small container of Metamucil®, it used to be that there were 6.8 grams of fiber in one tablespoon of Metamucil®. And one of my patients went to Sam's and got a huge container. She thought she would get it in bulk and it would be less expensive. And she was taking the same amount, and unfortunately, she didn't know this, she didn't read the label, but there were only 3.4 grams of fiber in a tablespoon. It had more fillers in this packaging of Metamucil®. So be sure your patients read the labels. They need 3.4 grams if they are taking it to slow down their GI tract. They need 6.8 grams if they are taking it to speed up their GI tract. There have been some questions about wafers. Wafers are a good substitute if the patient has frequent stooling, and two of the wafers is equivalent to the 3.4 grams of Metamucil®, or they can take one teaspoon. There is no substitute for the methylcellulose or the Citrucel®. So the wafers are very handy. They are very helpful if you are out to lunch. You don't have to mix up your Metamucil®. You just take the two wafers and follow it by two ounces of water.
The effects of medication on the GI tract are important to know because many medications affect GI transit, so know the medications that your patient is taking that may cause constipation, and know the medications that may cause diarrhea.
I have listed here some medications that induce constipation. Some of the most serious culprits that do this are narcotics, and a lot of our patients are on pain medication, and narcotics will definitely constipate the patient. And as you increase on the amount of narcotic, the constipation level will increase. The other major one that patients are not usually aware of is Zofran®, which is an antiemetic, which is very constipating and patients need to be aware of that. Also, vincristine and vinblastine.
Opiates' effect on the GI tract are as follows: first of all, opiates slow down the GI motility and so that the amount to opiate increases -- as you increase on the opiate amount, the motility in the gut slows down even more; and then secondary to the slow motility, more fluid is removed from the colon, causing the stools to become hard.
So if your patient is on opiates, give the patient a stimulant laxative to counteract the lack of peristaltic pushdown in the gut and give your patient a stool softener. This would be like docusate sodium, and they can take up to 500 mg a day. Automatically titrate the amount of both stimulants and softeners as opiate doses are adjusted. Many times we combine the two drugs into one medication called Senokot-S® or Senna-S in the generic form, and they can take up to eight of those, twice a day. Above eight Senna-S, there is no pharmacologic advantage to add more. If the patient is not responding to the eight Senna-S, then add a drug like Miralax®. Some of our patients need it once a day and some need it twice a day.
Medications that induce diarrhea: of course, laxatives would. People that buy antacids over the counter with a magnesium base can get diarrhea from that. Calcium-based antacids will cause constipation. Antibiotics can cause diarrhea because they kill off the normal flora in the GI tract and cause the diarrhea. Metoclopramide or Reglan® is a prokinetic drug and it will speed up the GI motility, and you see the other drugs listed here that also cause diarrhea.
Anticancer agents associated with diarrhea are listed here, but this is not an all-inclusive list, but just to give you an idea how important it is to understand the medications that your patient is taking so that you can offset and help the patient in managing these side effects on the GI tract.
Other causes of diarrhea: a rapid increase of fiber will cause diarrhea. It will cause also bloating and cramping, because if the gut is not used to taking in a lot of fiber. If you go from 10 grams of fiber per day and think "Oh I'm gonna get on the wagon and I'm gonna take my 40 grams of fiber," it won't work. It will just backfire, and they will have all these symptoms of diarrhea and bloating and cramps. So if you are going to give fiber, introduce it gradually. Also, enteral nutrition can cause diarrhea, and it is important to discuss with the dietitian, if the patient has been introduced to enteral nutrition and they are having diarrhea, be sure to check to see if there is something that might be less hyperosmolar that would cause less diarrhea for the patient. Impactions can cause diarrhea, and a lot of people are not aware of that. Patients think that every time they have diarrhea, that is a sign they need to offset that with something like Imodium® or Lomotil®, but if the colon is full of stool, the patient can have diarrhea because the stool from the small bowel, which is liquid, can seep around the formed stool in the colon, and thus they are impacted but they are having diarrhea. Another thing is if a patient has a fistula into the GI tract, that can increase diarrhea, and alcoholism can also induce diarrhea.
Diseases causing diarrhea are inflammatory bowel diseases, endocrine tumors, AIDS, intestinal/viral infections, and there are many different types. And people who have advanced diabetes can have nocturnal diarrhea, and patients with celiac sprue.
Now let's talk about a normal amount of gas. If you ask anybody "What's normal? How many times should I leave gas a day?" They will say "Oh, it's not normal at all." Well, the literature states it is normal to leave gas 15 times a day. The reason it is not normal to them is it is not normal to leave it in public, so I tell people, "Just get away from people, just kind of step away, and relieve your gas, and come back with the group that you're with."
Okay, what are the gas-producing foods? Cantaloupes, honeydew melons, cucumbers, green peppers, asparagus, broccoli, cauliflower, onions.... I'm sure some of those are no surprise to you because we all experience that, along with beans, okay. But I think the thing that really surprises people is carbonated beverages. Look at the amount of carbonated beverages we consume in our society. No wonder we have a lot of gas. And so the other thing is chewing gum. A lot of people do not realize that when they chew gum, they swallow air. So if you really want to help your patients, advise them, "Cut down on your carbonated beverages, beer, highly spiced foods and chewing gum." And some of the other things I mentioned previously. This will help control the gas.
If they need additional help, simethicone is a drug that is used to change big gas bubbles into smaller gas bubbles and the patient is much more comfortable. A common one that the people talk about is Gas-X®. That is the brand name for simethicone. Then there is Beano®. Beano® is a different type of drug. This is an enzyme that is used to digest beans and other vegetables and fruits that cause gas. And this is a sign that they do not have the enzyme in their system to digest these things, and so the Beano® is very helpful. It is important to take it, though, with the first mouthful of food. The next thing is drinking a hot liquid and lying over two pillows on your abdomen. This literally will push the gas right out. And I have seen a lot of people get a tremendous amount of benefit from doing this simple thing. Sometimes if it is really bad, a temporary rectal tube can be placed and this is not something that is kept in for a long period of time, but a #26 to #30 Foley catheter can be instilled into the colon, maybe about 10 inches. Do not blow up the balloon because it is not -- we want to prevent necrosis of the rectal mucosa, so just tape the catheter to the buttocks and leave it in place for about four hours, and then pull it out for about four hours, and then you can replace it again. This can be very helpful also in removing gas.
The last thing I would like to talk to you about is Ogilvie's Syndrome. Another name for this is pseudo-obstruction. Pseudo-obstruction -- first of all, you might want to say, "Well what is pseudo-obstruction?" And this is an acute colonic pseudo-obstruction. It happens in the colon where air fills up in the large bowel and also in the small bowel and in the middle of the small and large bowel is the cecum. And if the cecum dilates more than 12 cm, it can perforate. So I want you to be very attuned to the fact that, if your patient is really distended, get an abdominal series or something to determine if this is air or if this is stool, because if it is air, it can be a real emergency. And patients have perforated and have had to go to surgery for this. The usual treatment is to put the patient NPO, nothing by mouth, and then to put in an NG tube to decompress the stomach. And then sometimes, what I would always recommend is getting a gastroenterologist involved in this situation, because the patient will then need to be monitored and have serial abdominal series to assess the cecal diameter to make sure that it is not increasing in size. And sometimes they need to go to endoscopy and have that air sucked out of their colon. And sometimes the medication neostigmine is used to reduce the air in the colon, but it does have cardiac side effects. So I just want you to be aware of that.
So in summary, you have learned the importance of titrating food, fluid, fiber and medication for good bowel management; how fiber can be used in either speeding up or slowing down the GI motility; medications that can affect the GI motility; and you have learned about causes of gas and how to treat it. Thank you for your attention.
Overview of Factors Influencing Bowel Function video
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