This site is intended only for the use of Canadian Healthcare Professionals

Choose language:

Open Menu

Enteral Nutrition Intolerance - Part 2 (2019)

Podcast Banner

Hello and welcome to Clinical Nutrition Notes – a podcast where we speak with guest experts and opinion leaders about the art and science of clinical nutrition – brought to you by Nestlé Health Science Canada. This podcast is intended for health care professionals, for education purposes.

I am your host, Bethany Hopkins, Medical Affairs Manager with Nestle Health Science.

Today we will be talking with Anton Emmanuel M.D. about approaches to managing enteral nutrition intolerance. Dr. Emmanuel is an academic neuro-gastroenterologist at University College London and consultant gastroenterologist at University College Hospital and the National Hospital for Neurology and Neurosurgery at Queen Square. His clinical work encompasses being director of the G.I. physiology unit at University College Hospital as well as providing a gastroenterology service at Queen Square. Dr. Emmanuel's research includes basic gut neurophysiology and the study of the pathophysiology and management of gastrointestinal disorders of the upper and lower gut in neurological disease and functional conditions. He is the editor of the journal Frontline Gastroenterology.

Hopkins: Thank you for joining us Dr. Emmanuel. As a neuro-gastroenterologist you're involved in the management of many individuals receiving enteral nutrition. In our last conversation we began exploring enteral nutrition intolerance from its prevalence, the many G.I. symptoms patients are experiencing and how they present, to what clinicians should be thinking about when they're assessing these individuals.

Today we'll continue to explore this concept of enteral nutrition intolerance and G.I. symptoms but this time focusing on the management considerations for clinicians when they're working with these patients. So, I'd like you to begin with the upper-G.I. symptoms that patients may experience, and what are some of the management considerations that we should be thinking about.

Emmanuel: Thank you. So, yes, I think if we're talking about the upper-G.I. symptoms we'd sort of begin to lump in those patients who have either nausea/vomiting, or reflux symptoms, or early satiety after feed, or even those with abdominal discomfort. And we'd start looking at those, and the first thing I guess we'd all do as clinicians is to think about looking at the rate of, and the style of feeding we're giving. Should we carry on with infusion feeding, or should we think about bolus feeding? We should think about the time of feeding, sometimes we need to change the feed timing if the vomiting/diarrhea we mentioned last time suggests that actually that's a critical part of this, the feeding events are very much related to the vomiting episodes. Then sometimes we need to avoid that, to avoid the symptom triggers that are there. Sometimes patients say, “look the diary showed us that it happened after my exertional, my gym session,” and then we need to work around that.

Then, as I say, the other thing – it's really quite a big consideration and we're very invested in in my unit in London – is the idea of considering bolus feeding where possible. We can talk about what that means maybe, but that's quite an interesting issue. I think some of us have very set ideas, and I guess if I could summarize my perspective to be that I am open to the idea as an extra bit of the armamentarium rather than saying it's what everyone must do. But it's another option for change as we go through. Sometimes we say reduce feed volume and talk about making a different concentration of feed. Sometimes we reduce the size of water flushes as a way of trying to reduce the impact of this. Some of this may seem obvious to some of the listeners but actually for some of us, it's worth it, remembering these little things that may make a small difference.

Occasionally it's possible to suggest to the GP or similar the family doctor, changes of medication. It's not uncommon for patients to be taking anticholinergic drugs – which they don't need though given them after hospital admission – and they've just carried on being prescribed, and actually discontinuing the unnecessary antihistamine or the bladder medication can have a profound effect on reducing the burden on the patient. Or switching anti-Parkinsonian medication – a lot of patients who are taking these drugs have a side effect of making their bowel move slower and their whole gut move slower. Making sure the patient is in a good position, at least 45 degrees if possible, when they're fed or more upright, ensure the feed timings don't reduce the efficacy of other medications, especially the PPIs – the proton pump inhibitors. We know that if we are taking those drugs it's best taken on an empty stomach, and if somebody's having a very long continuous feed then the effect of those drugs is lost, and then their ability to reduce secretion and reduce vomiting is wasted. So, we have to train the patients to time their drug in those quiet moments.

So, there’s those first-line type things, and then there’s the second-line approaches which are to, we would say in very specific conditions if somebody has a lot of intolerances in their history we would think about talking about soy formulas where we suspect or know there are intolerances. If we have a patient who we’ve suspected from our assessment had a problem with gastric emptying and gastroparesis we would be very keen to start them on a whey-based peptide feed because we believe that makes a big difference to the kind of speed of digestion and their ability to get through the stomach more quickly. And then we move onto third-line options, which are the much more radical ones, which involve the wider team which is to consider other forms of say jejunal feeding or the like. So, there’s a lot of meat on that bone I’ve just mentioned there, and maybe we want to discuss some of that a bit more.

Hopkins: One of the questions I have for you when you’re talking about sort of those first-line options and you mentioned bolus feeding, and I know there’s lots of different definitions of what bolus feeding is or intermittent feeding. What do you mean by bolus feeding?

Emmanuel: You're absolutely right to pick me up because it's a term which is often used as a dichotomous – bolus versus continuous. And from my perspective bolus itself has got a spectrum to it. There's bolus feeding where you just give 50 mL boluses every so often, and then there's a feed where you put in 200, 250, 300 mL over a short infusion period, more like a meal as it were. And I think we would consider that there isn't enough data out there to say one is better than the other in any particular circumstance. But as I inferred, it's part of that kind of having a spectrum of things in our wardrobe which allows us to say, Ah, here's an option for us to think about because this is not working other ways. I think all I would say is that we mustn't, I would suggest, be too wedded to the idea that a continuous pump tube feed is the only option. It may be difficult to get the family and carers trained to safely use bolus feeding of whatever sort. But it's worth thinking about in certain cases.

Hopkins: I think in some cases perhaps patients and family members might like the flexibility of that as well, as opposed to using a pump. So, it's a little bit of trial and error isn't it, to sort of see what's going to work and what is the right rate in timing. Are there times when clinicians should avoid feeding, overnight for instance?

Emmanuel: This may seem a bit like heresy what I'm about to say now, but I offer it up as a bit of physiology. We know that in healthy individuals and in patients, that at night time you have the slowest and most reduced amount of contraction through the gut. So, your small bowel and your colon go to sleep when you go to sleep. And the idea of putting strain on that system by feeding it for most patients isn't an issue. But, there will be some patients who are super sensitive to that, so, their gut is dormant, and it suddenly having to do digestive work, and it can cause them to be restless or have discomfort. And we tend to think oh well, it is maybe some of them may just be, it's actually due to the fact that their gut is sensitive, it's not them being overly complaining, it's actually a sensitive gut. So, I think it's worth considering and again comes back to that idea of getting a diary or getting a patient to give you a bit more detailed history. We tend to take a history in a very sort of yes/no formula, and maybe the best way is to let patients make the observations themselves and say they're so…yeah, we are very keen on the idea of thinking about if we can avoid feeding overnight or when the bowel is at rest, that would be a good thing.

Hopkins: I know you have a lot of experience from your practice. Are there any case examples that really stand out for you as an illustration of how you've used nutrition and it's made a significant difference?

Emmanuel: So, I have quite a few patients with neurological disease who I look after who need feeding because of their swallow mechanism being unsafe. And in those patients, part of their neurological disease – I’m talking about things like motor neuron disease, Parkinson's disease, multiple sclerosis, when they have upper esophageal involvement, some of the patients I look after with severe strokes – part of their problem is not just the swallowing mechanism, the same insult, the same neurological injury which occurred to cause their swallowing problems also causes gastric emptying problems and therefore the rate of emptying of the stomach is a real issue, and the rate of digestion is a real issue.

And so, using a feed based on something other than the normal casein-based feeds for us is quite a desirable thing because we feel that the data is strong enough to say – look, in this situation where there is this problem of backing up and it's not responding to positional change or identifying changes in their diary, those are the patients where we are very keen to then move on to a whey-based feed. Because for us that makes a big difference in getting patients who otherwise would be thinking about moving onto jejunostomy feeds, so much more invasive things, or drugs even. I can think of about literally every month a situation where I'm with the dilemma of should I be changing a patient’s anti-emetic, giving them a prokinetic drug with its variability of effect and uncertain side effect? Should I be doing that versus switching them to a feed? And sometimes it's a bit more easy and often more successful to switch their feed regime than it is to make radical changes to their drug regime which they don't tolerate, should have a knock on effect on their bladder, or their spasms, or their mobility.

So, I think the reality is that very few tube patients are the neat, nice ones that we see on the posters. They often have more complex –should we say dirty – needs in there, and drugs are very powerful ways of making something dirty even dirtier. They are very powerful ways of making something simpler, but they have side effects, and if I can do something which manipulates people's outcomes without necessarily running the risk of changing their side effects, I will tend to think about that first. So, that's a very generic answer to a very specific question about patient groups, but that's one thing. The other group in particular is the diabetics…patients who have diabetes because even if they don’t have insulin dependent diabetes even type 2 diabetes these patients get gastroparesis, and that can be a real significant factor.

Hopkins: When you think about nutrition, I think of it as a low-tech solution and a low-risk alternative to, you know, use of medications in some individuals that can have a significant impact on managing some of these symptoms. So, thank you. Before we finish I'd just like to talk for a moment or have you talk for a moment about lower-G.I. symptoms that can be problematic for individuals and what you suggest for management of those.

Emmanuel: So, I think one of the first considerations for people who have a kind of constipated-type presentation is whether we need to think about fibre-based feeds. And if we recall the discussion we had last time, if patients have a slow transit type problem – just to recap, that means that infrequent urge to go and the hard stools – if they have that problem then giving them a higher-fibre diet is not particularly helpful. We know that high fibre in slow transit makes emptying worse in fact so, but the other patients who have the more normal transit problems. Then those ones in whom a higher-fibre diet will generally do well, and that's a pretty well-described observation. So, it's worth making that, that distinction between slow transit versus evacuation disorder and the ones that have a mix problem, they'll do well with a fibre diet as well. So that's the first consideration. And if you can’t change the fibre formula, just adding fibre to the formula may be another option that we find very beneficial, remembering that for the average female patient we have they need about 25 grams of fibre a day and the average male patient needs about 35 grams of fibre a day. So, if we factor those numbers in, that's a worthy consideration for the ones with non-slow transit, just emphasize that.

Again, I don't want to seem like I'm harping on about this, but we've had a very beneficial effect in some patients by that whole thing about increasing the rate of digestion when we switch them to a whey-based formula. We can see quite a few patients who've gone from a constipated phenotype to a more normal emptying. And sometimes we've had patients, I can think the one I've just saw last week, who said, “you know, I didn't know I was constipated despite all the questions, but I'm definitely emptying more completely when I go now, Doc.” That's not an unusual report. So that's something we've been aware of. And, of course there's a lot of attention in the non-fed community about low FODMAPs foods, and there is a bit of awareness that’s needed about the kind of fibre we're using around these fermentable and osmotically rich fibres.

For the patients with diarrhea, to focus on that for a second, we often just do a management strategy almost as a test. So we often suggest a trial reduction or cessation of feed to see whether there is this relationship because sometimes it's a relationship people think back to that liquid in/liquid out phenomena, but actually when they observe it they find that they're still getting diarrhea despite the feed, and that's quite a helpful observation for us because those are the ones in whom we think well they will need an anti-diarrheal drug because they have something wrong with their gut, or they may have small intestinal bacterial overgrowth, or they may need something additional to consider, or they may have an overflow problem. So that's the group in whom we'd say look the trial of cessation of feeding or reducing the rate can be quite helpful. And again, we occasionally try a peptide-type feed to reduce the osmolarity of the formula because that can be a factor for some patients with diarrhea.

So, what I would like to suggest is that there isn't a single magic bullet which sorts everything out. There isn't a single magic question that we can ask which will open the door. It's about having, from my perspective, it's like going to a restaurant having a menu where you open up and say right, here are the things I could have and today, I will just have an appetizer, or I'll just have a main course, and of the main courses I’ll have a… It's about having that options rather than say you must first have a main course then have dessert then have coffee. It doesn't work like that. From our perspective it's more about having a range of therapies.

Hopkins: I love that analogy. One last question before we close, as you were talking about fibre I started to think about water because I often think about fluid and fibre together. So, if you are increasing the fibre content in someone's diet through enteral formula or managing someone with diarrhea, that would be a consideration as well that people would need to be thinking about?

Emmanuel: You're absolutely right, yes, I glossed over that and thank you. We'd need to make sure that that fibre has something to work with. Fibre has two effects: a chemical effect on the gut bacteria and a physical effect of stretching the bowel out and that latter one needs the water. And the interesting thing is that for most of us at 10 to 15 grams of fiber a day the chemical effect is maxed out. Hence the reason why slow transit patients don't get any additional benefit. So, the physical effect, you need to maximize that by making sure there's adequate water on board to create that distension of the bowel and therefore the prokinetic effect of the fibre.

Hopkins: Thank you for sharing your perspective on the management of these various G.I. intolerance symptoms. This is a relatively common phenomena as you'd mentioned in tube fed individuals and one that can have a significant impact on patient’s, caregivers, and poses a real dilemma for clinicians. So, the management strategies that you shared today I believe will be a valuable tool in the tool box for clinicians when they do face these challenging predicaments. So, thank you Dr. Emmanuel for joining us, and thank you to our listeners.

(musical interlude)

CLOSING: This concludes this episode of our Clinical Nutrition Notes podcast.

To listen to more podcasts or to subscribe to Clinical Nutrition Notes, visit our website at

For the Nestlé Health Science podcast team, I'm Bethany Hopkins.