Transcript
Speaker: Welcome to Critical Matters, a sound podcast covering a broad range of topics related to the practice of intensive care medicine.
Speaker: Sound provides comprehensive critical care programs to hospitals across the country.
Speaker: To learn more about our programs and career opportunities, visit www.soundphysicians.com.
Speaker: And now your host, Dr. Sergio Zanotti.
Speaker: Every day in the ICU, we discuss issues related to the provision of enteral and parenteral nutrition in our patients.
Speaker: Proper nutrition to prevent or treat disease-related malnutrition in critically ill patients is a cornerstone of high-quality critical care.
Speaker: In today's podcast episode, we will discuss enteral nutrition in the ICU.
Speaker: Our guest is Dr. Leah Gramlich, a gastroenterologist and physician nutrition specialist based out of the Royal Alexandra Hospital in Alberta, Canada.
Speaker: She's a professor of medicine at the University of Alberta.
Speaker: She has held many leadership positions and is currently the provincial medical advisor for nutrition services in Alberta Health Services.
Speaker: Dr. Gramlich is the founding president of the Canadian Nutrition Society.
Speaker: She's a member of the board of directors of the American Society for Parenteral and Enteral Nutrition and is the chair of the Canadian Mild Nutrition Task Force.
Speaker: A prolific researcher, she has numerous publications, including a recent review article on enteral nutrition in hospitalized patients in the New England Journal of Medicine.
Speaker: We are grateful and privileged to have her on today.
Speaker: Leah, welcome to Critical Matters.
Speaker: Well, great to be here and thanks for having me, Sergio.
Speaker: Let's start with a simple question.
Speaker: Why should intensivists care about this topic?
Speaker: Nutrition is a
Speaker: important characteristic of the patient to address, particularly when they hit the ICU, whether it's because they're a post-op patient or they've developed worsening pneumonia on the floor and in our intensive care units around the world,
Speaker: There's an awareness that nutrition care should be provided, but there's also been lots of controversy about timing, dose, composition, so that it's a little bit confusing in the field and hard to know what's up-to-date information.
Speaker: Disease-related malnutrition in the ICU is something you talk about, obviously, in your review paper, and especially also in hospitalized patients.
Speaker: Could you just give us maybe a broad idea of the general incidence and impact on patient outcomes?
Speaker: It's a really good question and it is something that I'm passionate about.
Speaker: Over the past decade, we've been really trying to look at the prevalence and incidence of disease-related malnutrition in hospitalized patients.
Speaker: And we did a study called the Nutrition Care and Canadian Hospital Study, looked at over 1,000 Canadian patients in 20 centres.
Speaker: and up to one in two patients had evidence of malnutrition.
Speaker: And we used a robust tool called the Subjective Global Assessment that combines physical activity and historical findings.
Speaker: So in that study, 10% were severely malnourished and 33% were at risk for malnutrition.
Speaker: So that's in general hospitalized patients, that includes medical and surgical patients.
Speaker: In the ICU, because of the catabolism that accompanies acute critical illness, we know that substrates are being broken down and that these are often patients who aren't able to eat volitionally.
Speaker: In addition, nutrition care, once again, is a cornerstone of care of the critically ill patient.
Speaker: So there's an awareness of it.
Speaker: What about the impact on outcome?
Speaker: And so in our Nutrition Care in Canadian Hospitals study, as well as multiple studies around the world, the presence of malnutrition directly correlates with prolonged length of hospital stay, increased mortality rates, increased mortality rates,
Speaker: increase readmission rates and increase all cause complication rates.
Speaker: So malnutrition is prevalent.
Speaker: It impacts important outcomes for the patient and the health system.
Speaker: And we actually have strategies to address disease related malnutrition.
Speaker: Excellent.
Speaker: Is there a difference between medical nutrition therapy versus nutrition support?
Speaker: There is.
Speaker: So medical nutrition therapy is a big umbrella.
Speaker: That includes screening and assessing for malnutrition.
Speaker: So we're identifying those that are at risk.
Speaker: We typically use food first approaches to tailor meals.
Speaker: The use of oral nutrition supplements is considered in medical nutrition therapy, as is more specialized nutrition support like parenteral and enteral nutrition.
Speaker: So the concept of medical nutrition therapy is a broad concept that includes let's make sure we're optimizing oral intake with high caloric density products, but it also includes those methods of nutrition support, enteral and parenteral nutrition, which are used when a patient isn't able to eat adequate food by mouth.
Speaker: Could you define enteral nutrition versus parenteral nutrition?
Speaker: Entral nutrition is the provision of nutrients via a tube into the gastrointestinal tract.
Speaker: The tube may go through the nose, it may go through the mouth, and typically we use these tubes in patients who don't eat.
Speaker: It might be because they have an esophageal cancer.
Speaker: It might be because they have a duodenal outlet obstruction from acute severe pancreatitis.
Speaker: So we might use different tubes in different locations.
Speaker: Parenteral nutrition is the provision of nutrients via a vein, and it could be peripheral.
Speaker: So we're increasingly using peripheral parenteral nutrition in our ICUs as a safe start nutrition.
Speaker: It could be central parenteral nutrition, which allows you to deliver more energy protein-dense solutions that are in higher osmolality by a central vein, so it's easier to meet nutrient needs in small volumes of solutions.
Speaker: Could you share, Leah, with us general indications and contraindications for enteral nutrition?
Speaker: Yeah, great question.
Speaker: So enteral nutrition is indicated in patients who don't meet their needs with an oral diet.
Speaker: And we know that when patients first come to the hospital, particularly in the ICU, they're sick and they're not hungry oftentimes.
Speaker: So their oral dietary intake may be low.
Speaker: If it's less than 75% of what their estimated requirements are, and this persists for more than five days, we need to be thinking about the use of enteral nutrition.
Speaker: So enteral nutrition is indicated in patients who have an intact,
Speaker: but who aren't able to meet their requirements with oral nutrition of greater than 75% for more than five days.
Speaker: Let me intensify this.
Speaker: I've got a little smile on my face here, Sergio.
Speaker: We've got our cameras turned off.
Speaker: But there was a study done in about 2000 by Ville who looked at energy deficit in critically ill patients over a period of the first 10 days.
Speaker: And he had an inline indirect calorimeter.
Speaker: So these patients were ventilated and it constantly spit out what their measured resting energy expenditure was.
Speaker: And so they knew exactly what their calorie goals were.
Speaker: they were receiving.
Speaker: And once patients had an energy deficit of over 10,000 calories, so think a thousand calories a day for 10 days, there is a difference in mortality and outcome.
Speaker: And so that's in critically ill patients.
Speaker: And patients on the general medical and surgical wards, we're not as aggressive at ensuring feeding as we are in the ICU, but we should be thinking about
Speaker: and protein deficits and optimizing functional recovery and other outcomes.
Speaker: And this is a big issue with nutrition in the hospital.
Speaker: The fact that we just checked the box doesn't mean that we're doing the adequate nutrition support for that critically ill patient, correct?
Speaker: Correct.
Speaker: Absolutely.
Speaker: If we go to 10,000 feet, Sergio, and if we look at health system databases, there's a few publications out there that give us a sense for the prevalence of enteral nutrition.
Speaker: And in large health system databases, the prevalence of enteral nutrition in hospitalized patients is about 4%.
Speaker: So slightly less than one in 20 patients.
Speaker: In the ICU, enteral nutrition is used anywhere from in 60 to 80% of patients.
Speaker: So it's much more part of a standard of care in the ICU than it is on the general medical wards.
Speaker: And so that's why we've got a heightened interest in that unique setting.
Speaker: Could you talk a little bit more about some important studies in the field?
Speaker: The effort clinical trial is one that comes to mind in setting the stage for nutritional support.
Speaker: Right.
Speaker: So the EFFORT trial was published by Dr. Philip Schutz from Switzerland in 2019.
Speaker: This is truly my favorite study over the past decade.
Speaker: What Dr. Schutz and colleagues did is in hospitalized medical patients who had been screened.
Speaker: poor food intake.
Speaker: They were deemed at risk through a formal screening process.
Speaker: They took 2,000 patients and randomized them to standard care.
Speaker: Great, we know you're at nutrition risk.
Speaker: Let's make sure we're giving you your trace and that we're paying attention to your nutritional status versus that was the control group working with a nutritionist to take
Speaker: their dietary intake to optimize outcome.
Speaker: It's of note that in this study of 2,000 patients, 1,000 who got standard of care and 1,000 who got tailored nutrition intervention to provide increased energy and protein intake, being on enteral nutrition
Speaker: group ended up getting about 250 extra calories and about 15 extra grams of protein.
Speaker: So not that much, about as much as in a chocolate bar or a can of Ensure, for instance.
Speaker: And in that study, in contrast to the control group, there was a reduction in adverse events in that group of patients who got more calories, and there was a reduction in mortality.
Speaker: This reduction in adverse events correlated with a reduction in cost, and there are no increased side effects associated with the group that got more oral nutrition.
Speaker: Certain patients, think about it, out of 2,000 patients, about 11 ended up on enteral nutrition.
Speaker: So by using tailored approaches to optimize oral nutrition in hospitalized medical patients, we can improve intake and we can
Speaker: have an impact on outcome.
Speaker: For me, one of the most important findings that have me scratching my head on this study is that the provision of such a small amount of extra calories to obviate the deficit had a real impact on outcome.
Speaker: So a low number of calories has a positive and protein can have a positive impact on outcome.
Speaker: Are there any particular clinical trials that you really think are important for critically ill patients specifically?
Speaker: I think it's a really good question, and I hate to refer to this article, but the supplementary table, I did a lot of work on, and it's a supplementary table.
Speaker: But the interesting thing about the evidence in critical illness is that over the past 10 to 15 years, there have been a lot of very high-quality, well-designed, prospective, randomized controlled trials in the critically ill patient to help us understand timing,
Speaker: Do we start early?
Speaker: Do we start late?
Speaker: Dose?
Speaker: Do we feed full nutrition?
Speaker: What their estimated energy requirements are or measured energy requirements?
Speaker: Or do we actually use less than full feeding?
Speaker: Does it matter what phase of critical illness that the patient is in, does that influence the impact of feeding?
Speaker: And there have also been, so that's the timing, the dose of energy.
Speaker: What about the dose of protein has been looked at with the EFORT protein trial?
Speaker: And then there have been multiple randomized controlled trials looking at the use of antioxidants and micronutrient supplements.
Speaker: So a few of the more recent studies, and I think it really, it's not recent, that's what they said at the New England Journal, but in 2014, the Calories Study randomized 2,400 critically ill adult patients to receive either isocaloric, enteral, or parenteral nutrition within three days after ICU admission.
Speaker: And when they were fed isocalorically, there was no difference
Speaker: This is the first time we could say with certainty based on a randomized controlled trial that PN is not inferior nor is EN superior to parenteral nutrition in acute critical illness when they're provided in an isocaloric manner.
Speaker: More recently, the Nutritrea 2 trial randomized 2,400 patients with shock and mechanical ventilation to get isocaloric enteral or parenteral nutrition within 24 hours, and they set a target goal of 20 to 25 calories per kilo.
Speaker: Although there was no difference in 30-day mortality between the groups, so there was equivalence,
Speaker: In the early high-dose EN group, for enteral nutrition, there were more digestive complications.
Speaker: And I'm sure your intensivists listening to this would say, right, they get diarrhea, they get high rates of vomiting.
Speaker: And so once again, this led us to identify that higher-dose nutrition early
Speaker: when we're shooting for the target goal, which is easy to get with parenteral nutrition because we're not dealing with features of intolerance and inability to advance goal rates, in patients who are acutely critically ill, the most telling recent finding is that feeding patients goal rates are
Speaker: of their energy and protein targets in that first phase of acute physical critical illness seems to be associated with harm.
Speaker: And it's not associated with increased benefit.
Speaker: And that's independent of route of delivery, whether it's enteral or parenteral.
Speaker: And I'm going to stop right there, Sergio, because that's a lot of words.
Speaker: And I want to know if you've heard the words and understand what I'm saying.
Speaker: Yes, and this is an important concept because a lot of intensivists have grown under the impression that early is always better, that more is better than less, and
Speaker: and that enteral is superior to parenteral because they fear infectious complications, but they're not really looking at outcomes or other measures.
Speaker: So a lot of those are dogmas that the evidence might not support these days.
Speaker: And my understanding is that very similar to the conversation on mechanical ventilation, perhaps the mode of delivery is not as important as the goals that you achieve.
Speaker: and the nutritional support.
Speaker: And also there is no need to start immediately at a very high dose that might actually not provide any benefit and could harm.
Speaker: Is that correct?
Speaker: You hit it out of the park.
Speaker: You've got it.
Speaker: And let me tell you about the recent Nutritrea 3 study in which over 3,000 patients in shock were receiving mechanical ventilation and they were randomly assigned to get
Speaker: right now high dose nutrition which was 25 calories per kilo and one to 1.3 grams protein per kilo versus six calories per kilo and 0.2 to 0.4 grams of protein during the first week so that's seven days of therapy and this trial showed harm in the high dose group with a longer ICU stay and more complications and so once again
Speaker: maybe the biologic priority for that individual who's acutely critically ill is not nutrient metabolism.
Speaker: So hitting them fast and hard with full-dose therapy is not beneficial.
Speaker: The other finding more recently in the EFFORT protein trial, and there have been a few protein trials, is more protein better?
Speaker: And so Darren Hyland was lead author of this innovative clinical trial design that looked at centers that were prescribing more than 2.5 grams protein, 2 to 2.5 grams protein per kilo, compared to those less than 1%.
Speaker: 1.5 grams per kilo.
Speaker: And the group that got higher protein, it was actually closer to 1.5 grams per kilo.
Speaker: But the group that got high protein, they weren't getting 2 or 2.5 grams protein per kilo, but 1.5 grams per kilo.
Speaker: There was a higher likelihood of requiring CRRT and developing acute kidney injury.
Speaker: So not only was high protein provision not associated with any benefits such as reduction in length of stay or complications or reduction in ventilation requirement.
Speaker: It was associated with requirement for increased dialysis and acute kidney injury.
Speaker: So we really need to be thinking what is the host's capacity for metabolism and maybe acute critical illness isn't the right time.
Speaker: The trick is when does acute critical illness end?
Speaker: How do you know when that point is where you need to say, okay, right now I need to fill the gap because there's been a lot of catabolism with a lot of loss of nutrient substrate like muscle, lean tissue.
Speaker: And so that's the subject of investigation.
Speaker: Another unknown topic is what about when patients transition out of the ICU?
Speaker: Yeah.
Speaker: You might ask about other patient populations because patients come into the ICU from medical wards, surgical wards, and then they go out.
Speaker: The evidence is less robust.
Speaker: People aren't studying enteral versus parenteral in medical or surgical wards, and that's why that study from Schutz looking at nutrition care and provision of oral therapy was so relevant.
Speaker: larger studies in medicine and surgery.
Speaker: And for instance, in a study of a thousand hospitalized patients with various conditions, mostly medical patients, one in five had food intake below 70% of estimated requirements for a long period of time.
Speaker: So those are patients who might be candidates for enteral nutrition.
Speaker: And in this cohort, low food intake was increased with the increased risk of infection.
Speaker: In medical patients who had malnutrition, who got enteral nutrition, they actually had a lower incidence of complications than those who did not receive enteral nutrition.
Speaker: Similarly, in surgical patients, earlier provision seems to be helpful.
Speaker: And my guess is that in ICU,
Speaker: But in the complex medical and surgical patients, it's easy for a week to pass by dealing with their new enterocutaneous fistula or their evolving pneumonia and letting nutrition go to the back burner.
Speaker: I think we need to be looking much more closely at these complex medical and surgical patients who have persistently low food intake and risk for complications from malnutrition.
Speaker: And I think this all speaks to really having a much more individualized approach to our patients and trying to not throw all our critically ill patients into one category, one size fits all in terms of nutrition.
Speaker: I think teams are very good at checking the box.
Speaker: But part of why I wanted to talk about this topic is because I believe that we should go deeper for each patient and really try to understand what are the nutritional needs and the best timing based on what we know for this individual patient and not just say, well, all patients in my ICU get started on what we call very commonly trickle feeds on day one and things along those lines.
Speaker: Well, you think about it, trickle feeds, let's say it's 20 mils an hour.
Speaker: For 24 hours, that's 480 mils.
Speaker: We typically use a 1.5 calorie per cc product, so that's 750 calories.
Speaker: In the individual who weighs 70 kilos, let's say the requirements are 25 calories per kilo or 1,700 calories.
Speaker: That's about 50% of requirements.
Speaker: And we know that feeding full rates the first day, if you advance it, it's better.
Speaker: Having it prolonged, low delivery is not advantageous.
Speaker: So you're making good points.
Speaker: Let's shift gears to a little more of a practical aspect, which is the pathway for initiation of nutritional enteral nutrition in critically ill patients.
Speaker: And could we start with the timing?
Speaker: You mentioned a little bit about it, but just to recap and emphasize, how should we think about timing?
Speaker: Yeah.
Speaker: Right.
Speaker: So all patients admitted to hospital based on JCO guidelines, the American Academy of Dietetics, and other august bodies across the world have said all patients admitted to hospital shall be screened for malnutrition.
Speaker: And our electronic health records support this.
Speaker: You need an empowered nutrition service so that dietitians aren't seeing everyone.
Speaker: We want to save that skill workforce to see those at the highest risk.
Speaker: So we need health systems, nurses, unit clerks, patients themselves undertaking screening to identify those at risk.
Speaker: In our ICUs, all patients undergo typically a nutrition risk screen and an assessment prior to implementation of a nutrition care plan.
Speaker: And so assessment, we use the Canadian Nutrition Screening Tool in Canada.
Speaker: Two simple questions that all of you should be able to remember.
Speaker: You have to answer yes to both of these questions to screen positive.
Speaker: Have you lost weight without trying?
Speaker: And are you eating less than normal over the past two weeks?
Speaker: You answer yes to both of those questions.
Speaker: You screen positive for malnutrition and should be seen by a dietician to tailor interventions to meet your needs.
Speaker: The role of the ICU dietitian is different, and there is evidence to suggest that the FTE amount of dietitian you have in your ICU correlates with nutrition care and outcome.
Speaker: And so the dietitian clearly has a role in the intensive care unit to undertake initial screening and to...
Speaker: work with the team to ensure nutrition support is initiated.
Speaker: And so clearly enteral nutrition is the preferred route compared to parenteral nutrition.
Speaker: But if people don't tolerate it or you can't advance it, you shouldn't be thinking that parenteral nutrition is the poor cousin.
Speaker: It's not associated with poor outcome or, or, uh,
Speaker: less tolerance and it should be used.
Speaker: So the role of the dietician is to work as part of the multidisciplinary team to tailor the nutrition care, to be aware of the evidence-based guidelines that currently suggest that within ICU patient central nutrition should be initiated within 24 to 48 hours.
Speaker: And there's some difference between the European and the North American guidelines.
Speaker: And the goals are
Speaker: The American guidelines say 12 to 25 calories per day, and the Europeans say in the first three days, you don't want to exceed 70% of what their stated goal is, and you accelerate it after that.
Speaker: And goals for protein provision are typically about 1.3 grams kilo per day.
Speaker: So the dietician should be on top of that.
Speaker: In our ICUs, we have our dieticians using special assessment techniques like body composition.
Speaker: or they're using indirect calorimetry to measure energy expenditure.
Speaker: So we have a better handle on what exactly the targets for a given patient are.
Speaker: And so my expectation of our dietitians, and we work in multidisciplinary teams and have nutrition support teams in addition to our ICU teams, is to foster best nutrition care,
Speaker: be up to date on the evidence-based guidelines and to be aware of the patient's evolving status so that we can respond appropriately with appropriate nutrition care.
Speaker: And the dose for nutritional support usually comes in the ICU from our collaboration with our nutrition specialist.
Speaker: But could you give us kind of an overview of where we stand today based on evidence and
Speaker: Right, and so I kind of alluded to it.
Speaker: And so,
Speaker: For all of you, because intensivists often come from another realm, they might be surgeons or they might be respirologists, but a good starting point to know what people's nutrient requirements are.
Speaker: You, Sergio, sitting there, me sitting here, 25 calories per kilo is a reasonable guess.
Speaker: Listen, if I compare it to indirect calorimetry, I might be off.
Speaker: particularly if the patient is critically ill.
Speaker: But remember, that's a target for maintenance in the ICU, 20 to 25 calories.
Speaker: Early and critical illness because of the evidence for harmful feeding and because of features that patients have of feeding intolerance, such as hypertriglyceridemia, a BFM,
Speaker: that's rising out of proportion to creatinine, or challenging glycemic control.
Speaker: These are all features of metabolic intolerance.
Speaker: Your body's saying, wait, I can't handle those substrates.
Speaker: So the goal is 25 calories per kilo.
Speaker: That's challenging in the patient with obesity, where we often use a modified weight as opposed to their actual weight.
Speaker: We can base their energy provision on
Speaker: what their weight would be if their BMI was 25.
Speaker: So it's essentially a height-driven equation.
Speaker: And so the obese individual warrants special consideration, and we tend to underfeed in obesity.
Speaker: So a goal of 20 to 25 calories per kilo after day 3 to 7 is appropriate in the ICU.
Speaker: And when the patient enters into the recovery mode and you're ready to transition them out to the ward and they're rehabilitating from their multi-system organ failure or their multi-trauma following that treatment,
Speaker: a collision, for instance, you want to ensure that they have the right substrates to foster an albolism, to improve recovery and ultimately their functional status upon survivorship.
Speaker: And so at that time, we can't hold back on energy and protein provision
Speaker: if that's what's deemed required.
Speaker: So in recovery, you may need 35 to 45 calories per kilo.
Speaker: And for rehabilitation, it may be even higher than that.
Speaker: And your protein requirements may go up.
Speaker: So it really depends on what phase of critical illness you're at.
Speaker: And we need to tailor the solutions to the patient.
Speaker: But a good starting point is 25 calories per kilo, 1.3 grams protein per kilo.
Speaker: In medical inpatients with multiple existing comorbidities, the guidelines suggest 27 to 30 calories per kilo and 1.2 to 1.5 grams per protein per kilo, maybe a little bit less in people with impaired renal function and a GFR less than 30.
Speaker: And in surgical patients, the guidelines typically suggest 25 to 30 calories per kilo, 1.5 grams protein per kilo.
Speaker: Excellent.
Speaker: Is there a difference in the mode of delivery in terms of bolus feeding versus continuous enteral feeding?
Speaker: Yeah, it's a really good question.
Speaker: And I do a lot of home enteral nutrition.
Speaker: I have 600 clients.
Speaker: And for patients who are at home, to be able to bolus, use a 60 ml syringe and use four syringes over 15 minutes to get essentially the equivalent of lunch in, 350 calories, that's convenient.
Speaker: It also more closely mimics our feeding pattern when you and I eat.
Speaker: We don't eat continuously throughout the day.
Speaker: We might have breakfast, lunch, supper,
Speaker: And so that more closely feeds it.
Speaker: We use continuous feeding to get patients up to a goal rate.
Speaker: And for instance, in the critically ill patient with compromised perfusion, think about the fact that in the fed state, 25% of the cardiac output goes to the GI tract.
Speaker: That might be one of the reasons that our critically ill patients don't tolerate it because they got to get blood flow growing to brain and to heart and to other critical organs like kidneys.
Speaker: And so using low rates of continuous enteral nutrition is advantageous.
Speaker: And
Speaker: Oftentimes, we want to see if patients get abdominal distension or have nausea and potentially vomiting to see as a symptom of tube feeding intolerance.
Speaker: But at the end of the day, convenience makes a difference, standards of practice, and when any ICUs and on wards,
Speaker: They'll have an enteral feeding manual, and that will specify what a standard of practice is for a given institution.
Speaker: And continuous feeding is a little bit more burdensome for the patient as we transition out.
Speaker: Bolus feeding is potentially desirable.
Speaker: This might be a good point for you to settle for once and all the gastric residual dilemma.
Speaker: I think every intensivist gets a call every day about this.
Speaker: Yeah.
Speaker: You know, leaders like Steve McClave, who's a gastroenterologist, a real enteral leader from Kentucky, you know, in his ICUs, they don't measure gastric residuals anymore.
Speaker: It's become a habit.
Speaker: And, you know, what do you put your upper limit up?
Speaker: So there is no evidence that measuring gastric residuals impacts outcome or feeding.
Speaker: It seems kind of counterintuitive because if you've had a critically ill patient who's just, you might be intubated, but they've just vomited up a liter, you'd be thinking, oh gosh, that would have been a big gastric residual.
Speaker: Maybe we should have had an NG tube in that patient.
Speaker: But there's no evidence that suggests that measuring gastric residuals and holding tube feeds on that basis makes a difference.
Speaker: And this is still something that, despite guidelines, is very difficult to change at the bedside.
Speaker: They're patterns of practice, exactly.
Speaker: Could you share with us how we should think about the route of enteral nutrition in terms of the different accesses that we should be using in the ICU?
Speaker: Yeah, good question or good comment.
Speaker: Nasal gastric access is the easiest to get.
Speaker: It can be achieved with bedside placement.
Speaker: We shouldn't be using the standard 24 French nasal gastric tubes that are used for suction or 20 French tubes for suction.
Speaker: Those are hard on the nasal septum and they're not meant for feeding.
Speaker: So we should be using small bore silastic feeding tubes for patients.
Speaker: In the ICU, there have been techniques developed for post-pyloric placement of tubes, and I tend to be quite pragmatic in my approach.
Speaker: If there's a patient who is on very high oxygen requirements with lots of pressure support ventilation,
Speaker: with high oxygen flow, I'm really concerned that aspiration in that individual might be a life-ending event.
Speaker: And so in that individual, intragastric feeding may be risky, and I might err on the side of feeding post-pylorically.
Speaker: In individuals who we know have poor gastric emptying, the diabetic who's got diabetic gastroparesis, a patient who's had a previous gastrogegenostomy and who has anatomic perturbation and they're not tolerating intragastric feeding, you might choose post-pyloric feeding.
Speaker: So the go-to should be intragastric feeding, but a small silastic, small-bore tube, 10 to 12 French,
Speaker: in patients who you have concerns about their ventilatory status or risk of poor gastric emptying, pursuing post-pyloric access makes sense.
Speaker: In the area of pancreatitis, you know, where we think, gee, if we feed post-pylorically, maybe we will minimize pancreatic stimulation and complications.
Speaker: That's been debunked.
Speaker: And so in the setting of pancreatitis, intragastric feeding is what is recommended.
Speaker: However, from a practical experience,
Speaker: Pancreatitis, particularly if it involves the head and the neck of the pancreas, can result in a gastric outlet obstruction or duodenal obstruction.
Speaker: So in that individual, post-pyloric feeding might be advantageous.
Speaker: An individual who has a requirement
Speaker: hasoenteric access for more than six weeks, you should be thinking about getting a more permanent access, whether it's a precutaneous endoscopic gastrostomy tube or a radiologic gastrostomy or a jejunostomy tube should be considered.
Speaker: Perfect.
Speaker: I wanted to talk about
Speaker: strategies to reduce harm and maximize the benefits of enteral and nutrition in our patients, looking at different categories.
Speaker: And we'd like to start with a metabolic, two issues that are frequent are proglycemia control and refeeding syndrome.
Speaker: Yeah.
Speaker: There's...
Speaker: Thanks to Gret Badenberg for having us all look at glycemic control.
Speaker: And we know it's hard to keep people less than six, but we know that glycemic control in critically ill patients is associated with enhanced outcome.
Speaker: And so I really like nice sugar.
Speaker: Blood sugars need to be between...
Speaker: eight to 10.
Speaker: I'm happy with a blood sugar less than 10 and using glycemic control protocols can be really helpful with this.
Speaker: And I think that needs to be done with the team, not advancing either enteral or parenteral nutrition.
Speaker: If you don't have glycemic control, blood sugars less than 10 makes a lot of sense.
Speaker: In my brain, this is linked to metabolic intolerance.
Speaker: we're increasingly recognizing both refeeding syndrome and refeeding hypophosphatemia, and there's been much more literature, although not a lot of prospective trials in this area.
Speaker: I'm a clinician at baseline, and if I see someone with a low phosphorus and a low potassium, let's say their phosphorus is 0.6 and their potassium is 3.2, we have to be thinking that these two...
Speaker: electrolytes, minerals are the main intracellular cations.
Speaker: And if their levels are low in the intravascular space, that means they are very depleted into intracellular space.
Speaker: And that when we feed carbohydrate and insulin levels go up,
Speaker: There's intracellular transition of phosphorus and potassium, which can result in critical arrhythmias, such as atrial fibrillation and the development of heart failure, which is the sine qua non of rheumatoid.
Speaker: of refeeding hypophosphatemia in that individual who at baseline has low phosphorus, low potassium, low mag.
Speaker: You're also thinking, could their selenium be low?
Speaker: Could their thiamine be low?
Speaker: You feed them expectantly and don't advance carbohydrate delivery until you've got a handle on micronutrient stability.
Speaker: Excellent.
Speaker: A topic in the GI kind of complications that is very relevant to the ICU is bowel ischemia or the fear of bowel ischemia.
Speaker: And when do we feed somebody on basal pressors?
Speaker: Could you comment on that?
Speaker: Yeah, absolutely.
Speaker: Nutritrea 1, 2, and 3, these three large prospective randomized control trials that really looked at patients who were in shock on pressors, uh,
Speaker: In the first decade of 2000, intensivists wanted to feed only enterally and parenteral nutrition was poison and we wanted to give full rates.
Speaker: And there is evidence that advancing to full rate enteral nutrition can precipitate.
Speaker: intestinal ischemia.
Speaker: Think about that cardiac output in the fed state.
Speaker: And so in Nutritrea 3, we know that you want to not push energy delivery and that in patients where we're pushing enteral feeding, we can increase potential for GI side effects.
Speaker: The American Society of Parenteral and Enteral Nutrition came out with a potential score to use, but there are no real hard and fast guidelines about what specific doses of pressors we need to be conscientious of.
Speaker: But if you've got a patient on high-dose pressors, then you should be thinking, is it risky to be advancing enteral feeding at this time?
Speaker: And potentially nausea, vomiting, diarrhea are important.
Speaker: features of GI ischemia.
Speaker: They're symptoms that allow us to think, well, this is not being tolerated.
Speaker: Just as a little aside, if we think of all the injury severity scores and critical illness, like Apache, for instance, it tells us about kidney function, cognitive function, but it doesn't give us any GI signals.
Speaker: The SOFA score includes some liver function tests, but no GI signals.
Speaker: Maybe...
Speaker: diarrhea is not included in the scores or high gastric residuals or vomiting but i don't think we actually identify gi organ function or dysfunction very well with our current injury severity scores in icu but that if we use common sense maybe intolerance of enteral nutrition in someone who's hypotensive on lots of pressors should be a
Speaker: a red flag that we might be precipitating ischemia.
Speaker: Excellent.
Speaker: You did mention aspiration risk and aspiration pneumonia is a concern we have obviously in the ICU.
Speaker: Any strategies to minimize this in addition to what you discussed?
Speaker: You know, it's pretty clear if you look at the evidence that aspiration pneumonia, the vast majority of the time is not related to enteral feeding, but it's related to aspiration of oral secretions.
Speaker: And so, you know, appropriate trait care in patients who do have poor gastric emptying.
Speaker: And they may have high gastric residuals if you measure them.
Speaker: And so think of the person in ICU who would have poor gastric emptying.
Speaker: Typically, that's the diabetic.
Speaker: I'm not sure what it's like in your hospitals, but our prevalence of diabetes is
Speaker: in our hospitals now is about 14%.
Speaker: When I was in training in Boston 35 years ago, it was 4%.
Speaker: And so in certain parts of the US, I can imagine it's higher than that.
Speaker: Patients with poorly controlled diabetes and complications of diabetic gastroparesis are at that high risk.
Speaker: Patients who've had problems with gastric outlet obstruction.
Speaker: So those are the patients you want to look at for aspiration risk.
Speaker: and treat appropriately, appropriate suctioning and trait care is also relevant.
Speaker: I guess also being parsimonious.
Speaker: If you're running tube feeding at 100 an hour and they're vomiting, turn down the tube feeds.
Speaker: There is a lot of role for common sense.
Speaker: For sure.
Speaker: And finally, mechanical complications are not uncommon.
Speaker: What are your suggestions or recommendations for dealing with either clogged feeding tubes or tube displacement?
Speaker: Well, you know, the smaller tubes you're using, they are at risk for clogging.
Speaker: And a simple method is to flush the enteral tube after administration of medications in particular and during tube feeding.
Speaker: So using liquid medications, recognizing that these small silastic small bore tubes are
Speaker: are not meant for medication.
Speaker: So an ounce of prevention for clogged feeding tubes by using liquid medications and crushing medications.
Speaker: The other thing is some sites may be using these small bore tubes to check gastric residual volumes if that's still a standard of practice in your unit.
Speaker: And these tubes aren't meant to be used to check gastric residuals.
Speaker: So avoiding that would be good.
Speaker: Perfect.
Speaker: As we close, are there any pitfalls, common pitfalls that we should avoid?
Speaker: And what would be your final pearls of wisdom on the topic?
Speaker: You know what, we have learned a lot over the past decade.
Speaker: And it's important to acknowledge
Speaker: wealth of expertise that exists within the ICU field to conduct really timely, effective, randomized controlled trials.
Speaker: But isn't it interesting after all these RCTs, we're still uncertain because the patients confuse us.
Speaker: So the first common pitfall to avoid is to try to meet nutrient requirements immediately in the critically ill patient.
Speaker: It's been identified that that's associated with harm and that we need to let that acute phase of critical illness declare itself.
Speaker: It's the first few busy days in ICU.
Speaker: But by day three to seven, we should be thinking, do we need to be working more towards achieving
Speaker: energy requirements with their nutrition feeding.
Speaker: Don't be scared to use TPN.
Speaker: PN is not poison.
Speaker: And if there's someone who comes into your unit, it's the first to
Speaker: critical illness and at baseline their body mass index is 16 or 18, jump on the bandwagon, make the assumption that they are severely malnourished and they need nutrition, micronutrients and macronutrients.
Speaker: So tailor the care to the individual patient and the patient with obesity and
Speaker: Don't make the assumption that they are well-fed, that they can live off the fat of the land, because in the obese individual, they often have sarcopenia and not much to rely on.
Speaker: And it's really clear in our general studies of critically ill patients.
Speaker: We did one study where the obese individual with a BMI over 35 is getting on average 6 to 8 calories per kilo and 0.4 grams protein to 0.6 grams of protein.
Speaker: protein per kilo in the obese individual they're often the ones who are on the ventilator for the long time they're hard to rehabilitate so tailoring our therapy to particularly those at extremes of weight i think is relevant perfect leah as we close on the podcast we'd like to ask a couple questions that are unrelated to the clinical topic would that be okay sure
Speaker: The first question relates to books.
Speaker: Is there a book that has influenced you significantly or a book that you have gifted often to other people?
Speaker: Well, you know what, I'm a reader, I'm part of a book club, and I grew up across the street from the library, so I probably read 50 books a year.
Speaker: But one book that really stood out for me was called The Overstory.
Speaker: It was published in 2018 by a fellow named Richard Powers, who won the Pulitzer Prize for this work.
Speaker: And
Speaker: The Overstory is a story about trees.
Speaker: And this is the first time I had given trees a thought.
Speaker: And I think that it had me think about my environment more.
Speaker: So it was very compelling.
Speaker: It is a great read for anyone who wants to read.
Speaker: I agree.
Speaker: And when I read that book, the first thing that came to mind were the ants in Lord of the Rings.
Speaker: Yeah.
Speaker: So you read the book too.
Speaker: What did you think of it?
Speaker: Did it stand out in your mind?
Speaker: It did.
Speaker: And not only the story is captivating and it made me think about what's around me when I walk, but also such a creative approach, right?
Speaker: Highly recommended.
Speaker: So we will definitely link that in the show notes.
Speaker: The second question relates to changing your mind.
Speaker: Could you share with us something you changed your mind about over the last few years?
Speaker: Right.
Speaker: You know, from a personal perspective, and even building on the overstory with this link to nature, I'm getting on in my career.
Speaker: I'm 62, and I'm actually thinking about how do I go slow as opposed to fast?
Speaker: And so that's been an evolution.
Speaker: But in the area of nutrition, because we have really advanced nutrition support teams and we're linked across a health system, and I like to use my provincial role to affect change at a health system level, but at the same time focus on the individual patient.
Speaker: And so in our nutrition care practice, we're going to more...
Speaker: multi-chamber bag, what was previously known as pre-mix PN, and we're using a lot more peripheral parenteral nutrition.
Speaker: In fact, our intensivists during COVID used PPN as safe start nutrition.
Speaker: So PN in the ICU got a really bad rap for a couple decades, and mine was one of the only voices saying, wait, I take care of patients who live on TPN for decades in my intestinal failure practice.
Speaker: It is not poison.
Speaker: We need to be thinking about other things.
Speaker: So, for instance, with peripheral parenteral nutrition, which is easily provided by a peripheral access without risk of central thrombosis, two liters gives you 1,400 calories a day and 50 grams of protein.
Speaker: That's not bad.
Speaker: So I think that we're going to, in our health system, look at the use of pre-mix or multi-chamber bags in a more wide variety of patients simply because a multi-chamber bag PN is
Speaker: It's got a longer shelf stability.
Speaker: It's safe.
Speaker: It results in less infectious complications.
Speaker: So that's a change that we're looking at in our health system over the past few years, whereas previously we thought, oh my gosh, I've got to give you the perfect TPN recipe.
Speaker: We know that we're feeding enteral nutrition.
Speaker: We got a couple of products and we can give it to people and meet their electrolyte needs and macronutrient needs.
Speaker: I'm shifting my focus a little bit.
Speaker: patients that can benefit from a multi-chamber bag or pre-mix solution without the attendant time it takes with safety in mind and health system outcomes in mind.
Speaker: Perfect.
Speaker: And to close, is there a thought, could be a quote, a fact, or just a thought that you would like to share with all our listeners, something you want every intensivist to know?
Speaker: The short one is PN is not poison.
Speaker: And I would hope that most intensives know, but I presented my summation of this information to a group of gastroenterologists who I work with regularly and they're knowledgeable.
Speaker: They still hadn't caught up with the PN is not poison.
Speaker: There's a little bit of confusion in the literature.
Speaker: And I think that with the excellent research work that's been done over the past decade, what we do know is that
Speaker: Few days, the acute phase of critical illness, patients who are fed what their nutrient requirements are do not do as well.
Speaker: So it's not the type of nutrition they're getting.
Speaker: It's the dose in that acute phase when it's not the biologic priority of the patient to be undertaking nutrient metabolism.
Speaker: I believe this is a very important message because my feeling is that most intensivists still believe that PN should be avoided at all costs.
Speaker: No, that clearly is not true.
Speaker: Yeah, and I think we are doing a disservice to our patients in some instances and just understand also that what we should be focused on is individualizing PNs.
Speaker: the care for the needs of that patient and then figuring out, okay, which mode will allow me to deliver that at this time.
Speaker: Exactly.
Speaker: Well, Leah, I really want to thank you for sharing your time and your expertise with our listeners.
Speaker: Look forward to having you back on the podcast.
Speaker: And definitely for those who have not read the overstory, highly, highly recommend it.
Speaker: Thank you.
Speaker: Thank you very much.
Speaker: Good.
Speaker: Thank you for listening to Critical Matters, a sound podcast.
Speaker: Make sure to subscribe to Critical Matters on Apple or Google Podcasts and share with your network.
Speaker: Sounds transforming the way critical care is provided in hospitals across the country.
Speaker: To learn more, visit www.soundphysicians.com.
