Become a Creator today!Start creating today - Share your story with the world!
Start for free
00:00:00
00:00:01
Enteral Nutrition in the ICU
1 Plays9 months ago
In this episode of, Dr. Sergio Zanotti explores the vital role of enteral nutrition in the ICU—a foundational element in the prevention and treatment of disease-related malnutrition among critically ill patients. He is joined by Dr. Leah Gramlich, a distinguished gastroenterologist and physician nutrition specialist from the Royal Alexandra Hospital in Alberta, Canada. Dr. Gramlich is a Professor of Medicine at the University of Alberta and the founding president of the Canadian Nutrition Society. She has also served on the Board of Directors for the American Society for Parenteral and Enteral Nutrition and chaired the Canadian Malnutrition Task Force, bringing deep expertise to this essential topic.
Additional resources:
Enteral Nutrition in Hospitalized Adults. Lead Gramlich, Peggi Guenter. New Engl J Med 2025: https://pubmed.ncbi.nlm.nih.gov/40239069/
Individualized nutritional support in medical inpatients at nutritional risk: a randomized clinical trial. The EFFORT Clinical Trial. Lancet 2019: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(18)32776-4/abstract
Low versus standard calorie and protein feeding in ventilated adults with shock: a randomised, controlled, multicentre, open-label, parallel-group trial (NUTRIREA-3). Lancet Respir Med 2023: https://pubmed.ncbi.nlm.nih.gov/36958363/
The effect of higher protein dosing in critically ill patients with high nutritional risk (EFFORT Protein): an international, multicentre, pragmatic, registry-based randomised trial. Lancet 2023: https://pubmed.ncbi.nlm.nih.gov/36708732/
Books mentioned in this episode:
The Overstory: A Novel. By Richard Powers: https://bit.ly/43Drra1
Recommended
Transcript
Introduction to Critical Matters Podcast
00:00:06
Speaker
Welcome to Critical Matters, a sound podcast covering a broad range of topics related to the practice of intensive care medicine.
00:00:14
Speaker
Sound provides comprehensive critical care programs to hospitals across the country.
00:00:19
Speaker
To learn more about our programs and career opportunities, visit www.soundphysicians.com.
Importance of Nutrition in Critical Care
00:00:26
Speaker
And now your host, Dr. Sergio Zanotti.
00:00:33
Speaker
Every day in the ICU, we discuss issues related to the provision of enteral and parenteral nutrition in our patients.
00:00:40
Speaker
Proper nutrition to prevent or treat disease-related malnutrition in critically ill patients is a cornerstone of high-quality critical care.
00:00:47
Speaker
In today's podcast episode, we will discuss enteral nutrition in the ICU.
Introduction to Dr. Leah Gramlich
00:00:53
Speaker
Our guest is Dr. Leah Gramlich, a gastroenterologist and physician nutrition specialist based out of the Royal Alexandra Hospital in Alberta, Canada.
00:01:01
Speaker
She's a professor of medicine at the University of Alberta.
00:01:05
Speaker
She has held many leadership positions and is currently the provincial medical advisor for nutrition services in Alberta Health Services.
00:01:13
Speaker
Dr. Gramlich is the founding president of the Canadian Nutrition Society.
00:01:17
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.
00:01:25
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.
00:01:35
Speaker
We are grateful and privileged to have her on today.
00:01:37
Speaker
Leah, welcome to Critical Matters.
00:01:40
Speaker
Well, great to be here and thanks for having me, Sergio.
Why Focus on Nutrition in ICU?
00:01:44
Speaker
Let's start with a simple question.
00:01:46
Speaker
Why should intensivists care about this topic?
00:01:51
Speaker
Nutrition is a
00:01:53
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,
00:02:08
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.
Impact of Disease-Related Malnutrition
00:02:26
Speaker
Disease-related malnutrition in the ICU is something you talk about, obviously, in your review paper, and especially also in hospitalized patients.
00:02:37
Speaker
Could you just give us maybe a broad idea of the general incidence and impact on patient outcomes?
00:02:45
Speaker
It's a really good question and it is something that I'm passionate about.
00:02:50
Speaker
Over the past decade, we've been really trying to look at the prevalence and incidence of disease-related malnutrition in hospitalized patients.
00:02:58
Speaker
And we did a study called the Nutrition Care and Canadian Hospital Study, looked at over 1,000 Canadian patients in 20 centres.
00:03:06
Speaker
and up to one in two patients had evidence of malnutrition.
00:03:11
Speaker
And we used a robust tool called the Subjective Global Assessment that combines physical activity and historical findings.
00:03:18
Speaker
So in that study, 10% were severely malnourished and 33% were at risk for malnutrition.
00:03:27
Speaker
So that's in general hospitalized patients, that includes medical and surgical patients.
00:03:33
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.
00:03:46
Speaker
In addition, nutrition care, once again, is a cornerstone of care of the critically ill patient.
00:03:52
Speaker
So there's an awareness of it.
00:03:55
Speaker
What about the impact on outcome?
00:03:57
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,
00:04:12
Speaker
increase readmission rates and increase all cause complication rates.
00:04:17
Speaker
So malnutrition is prevalent.
00:04:20
Speaker
It impacts important outcomes for the patient and the health system.
00:04:25
Speaker
And we actually have strategies to address disease related malnutrition.
00:04:31
Speaker
Excellent.
00:04:32
Speaker
Is there a difference between medical nutrition therapy versus nutrition support?
00:04:38
Speaker
There is.
00:04:38
Speaker
So medical nutrition therapy is a big umbrella.
00:04:41
Speaker
That includes screening and assessing for malnutrition.
00:04:45
Speaker
So we're identifying those that are at risk.
00:04:48
Speaker
We typically use food first approaches to tailor meals.
00:04:54
Speaker
The use of oral nutrition supplements is considered in medical nutrition therapy, as is more specialized nutrition support like parenteral and enteral nutrition.
00:05:05
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.
00:05:28
Speaker
Could you define enteral nutrition versus parenteral nutrition?
Enteral vs. Parenteral Nutrition in ICU
00:05:34
Speaker
Entral nutrition is the provision of nutrients via a tube into the gastrointestinal tract.
00:05:42
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.
00:05:56
Speaker
It might be because they have an esophageal cancer.
00:05:59
Speaker
It might be because they have a duodenal outlet obstruction from acute severe pancreatitis.
00:06:04
Speaker
So we might use different tubes in different locations.
00:06:08
Speaker
Parenteral nutrition is the provision of nutrients via a vein, and it could be peripheral.
00:06:14
Speaker
So we're increasingly using peripheral parenteral nutrition in our ICUs as a safe start nutrition.
00:06:21
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.
00:06:37
Speaker
Could you share, Leah, with us general indications and contraindications for enteral nutrition?
00:06:43
Speaker
Yeah, great question.
00:06:45
Speaker
So enteral nutrition is indicated in patients who don't meet their needs with an oral diet.
00:06:55
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.
00:07:02
Speaker
So their oral dietary intake may be low.
00:07:05
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.
00:07:19
Speaker
So enteral nutrition is indicated in patients who have an intact,
00:07:26
Speaker
but who aren't able to meet their requirements with oral nutrition of greater than 75% for more than five days.
00:07:38
Speaker
Let me intensify this.
00:07:40
Speaker
I've got a little smile on my face here, Sergio.
00:07:43
Speaker
We've got our cameras turned off.
00:07:45
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.
00:07:58
Speaker
And he had an inline indirect calorimeter.
00:08:01
Speaker
So these patients were ventilated and it constantly spit out what their measured resting energy expenditure was.
00:08:08
Speaker
And so they knew exactly what their calorie goals were.
00:08:13
Speaker
they were receiving.
00:08:15
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.
00:08:26
Speaker
And so that's in critically ill patients.
00:08:30
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
00:08:42
Speaker
and protein deficits and optimizing functional recovery and other outcomes.
00:08:49
Speaker
And this is a big issue with nutrition in the hospital.
00:08:53
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?
00:09:01
Speaker
Correct.
00:09:02
Speaker
Absolutely.
00:09:03
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.
00:09:15
Speaker
And in large health system databases, the prevalence of enteral nutrition in hospitalized patients is about 4%.
00:09:23
Speaker
So slightly less than one in 20 patients.
00:09:27
Speaker
In the ICU, enteral nutrition is used anywhere from in 60 to 80% of patients.
00:09:34
Speaker
So it's much more part of a standard of care in the ICU than it is on the general medical wards.
00:09:40
Speaker
And so that's why we've got a heightened interest in that unique setting.
00:09:46
Speaker
Could you talk a little bit more about some important studies
The EFFORT Trial and Nutrition Interventions
00:09:52
Speaker
in the field?
00:09:52
Speaker
The effort clinical trial is one that comes to mind in setting the stage for nutritional support.
00:10:00
Speaker
Right.
00:10:01
Speaker
So the EFFORT trial was published by Dr. Philip Schutz from Switzerland in 2019.
00:10:08
Speaker
This is truly my favorite study over the past decade.
00:10:11
Speaker
What Dr. Schutz and colleagues did is in hospitalized medical patients who had been screened.
00:10:24
Speaker
poor food intake.
00:10:25
Speaker
They were deemed at risk through a formal screening process.
00:10:29
Speaker
They took 2,000 patients and randomized them to standard care.
00:10:33
Speaker
Great, we know you're at nutrition risk.
00:10:35
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
00:10:48
Speaker
their dietary intake to optimize outcome.
00:10:52
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
00:11:12
Speaker
group ended up getting about 250 extra calories and about 15 extra grams of protein.
00:11:19
Speaker
So not that much, about as much as in a chocolate bar or a can of Ensure, for instance.
00:11:24
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.
00:11:39
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.
00:11:54
Speaker
Certain patients, think about it, out of 2,000 patients, about 11 ended up on enteral nutrition.
00:12:01
Speaker
So by using tailored approaches to optimize oral nutrition in hospitalized medical patients, we can improve intake and we can
00:12:09
Speaker
have an impact on outcome.
00:12:11
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.
00:12:29
Speaker
So a low number of calories has a positive and protein can have a positive impact on outcome.
00:12:40
Speaker
Are there any particular clinical trials that you really think are important for critically ill patients specifically?
00:12:51
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.
00:12:59
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,
00:13:21
Speaker
Do we start early?
Clinical Trials on Nutrition Timing and Dose
00:13:22
Speaker
Do we start late?
00:13:24
Speaker
Dose?
00:13:25
Speaker
Do we feed full nutrition?
00:13:27
Speaker
What their estimated energy requirements are or measured energy requirements?
00:13:32
Speaker
Or do we actually use less than full feeding?
00:13:36
Speaker
Does it matter what phase of critical illness that the patient is in, does that influence the impact of feeding?
00:13:43
Speaker
And there have also been, so that's the timing, the dose of energy.
00:13:48
Speaker
What about the dose of protein has been looked at with the EFORT protein trial?
00:13:53
Speaker
And then there have been multiple randomized controlled trials looking at the use of antioxidants and micronutrient supplements.
00:14:01
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.
00:14:25
Speaker
And when they were fed isocalorically, there was no difference
00:14:35
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.
00:14:55
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.
00:15:13
Speaker
Although there was no difference in 30-day mortality between the groups, so there was equivalence,
00:15:19
Speaker
In the early high-dose EN group, for enteral nutrition, there were more digestive complications.
00:15:24
Speaker
And I'm sure your intensivists listening to this would say, right, they get diarrhea, they get high rates of vomiting.
00:15:31
Speaker
And so once again, this led us to identify that higher-dose nutrition early
00:15:46
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
00:16:10
Speaker
of their energy and protein targets in that first phase of acute physical critical illness seems to be associated with harm.
00:16:20
Speaker
And it's not associated with increased benefit.
00:16:23
Speaker
And that's independent of route of delivery, whether it's enteral or parenteral.
00:16:29
Speaker
And I'm going to stop right there, Sergio, because that's a lot of words.
00:16:32
Speaker
And I want to know if you've heard the words and understand what I'm saying.
00:16:38
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
00:16:54
Speaker
and that enteral is superior to parenteral because they fear infectious complications, but they're not really looking at outcomes or other measures.
00:17:02
Speaker
So a lot of those are dogmas that the evidence might not support these days.
00:17:09
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.
00:17:21
Speaker
and the nutritional support.
00:17:23
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.
00:17:31
Speaker
Is that correct?
00:17:33
Speaker
You hit it out of the park.
00:17:35
Speaker
You've got it.
00:17:35
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
00:17:50
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
00:18:16
Speaker
maybe the biologic priority for that individual who's acutely critically ill is not nutrient metabolism.
00:18:24
Speaker
So hitting them fast and hard with full-dose therapy is not beneficial.
00:18:30
Speaker
The other finding more recently in the EFFORT protein trial, and there have been a few protein trials, is more protein better?
00:18:36
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%.
00:18:52
Speaker
1.5 grams per kilo.
00:18:55
Speaker
And the group that got higher protein, it was actually closer to 1.5 grams per kilo.
00:19:01
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.
00:19:08
Speaker
There was a higher likelihood of requiring CRRT and developing acute kidney injury.
Risks of High Protein Provision
00:19:15
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.
00:19:27
Speaker
It was associated with requirement for increased dialysis and acute kidney injury.
00:19:32
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.
00:19:41
Speaker
The trick is when does acute critical illness end?
00:19:44
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.
00:19:57
Speaker
And so that's the subject of investigation.
00:19:59
Speaker
Another unknown topic is what about when patients transition out of the ICU?
00:20:04
Speaker
Yeah.
00:20:06
Speaker
You might ask about other patient populations because patients come into the ICU from medical wards, surgical wards, and then they go out.
00:20:15
Speaker
The evidence is less robust.
00:20:17
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.
00:20:31
Speaker
larger studies in medicine and surgery.
00:20:34
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.
00:20:51
Speaker
So those are patients who might be candidates for enteral nutrition.
00:20:54
Speaker
And in this cohort, low food intake was increased with the increased risk of infection.
00:21:01
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.
00:21:14
Speaker
Similarly, in surgical patients, earlier provision seems to be helpful.
00:21:19
Speaker
And my guess is that in ICU,
00:21:28
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.
00:21:41
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.
00:21:54
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.
00:22:08
Speaker
I think teams are very good at checking the box.
00:22:11
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.
00:22:35
Speaker
Well, you think about it, trickle feeds, let's say it's 20 mils an hour.
00:22:40
Speaker
For 24 hours, that's 480 mils.
00:22:42
Speaker
We typically use a 1.5 calorie per cc product, so that's 750 calories.
00:22:50
Speaker
In the individual who weighs 70 kilos, let's say the requirements are 25 calories per kilo or 1,700 calories.
00:22:54
Speaker
That's about 50% of requirements.
00:23:01
Speaker
And we know that feeding full rates the first day, if you advance it, it's better.
00:23:05
Speaker
Having it prolonged, low delivery is not advantageous.
00:23:09
Speaker
So you're making good points.
00:23:13
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.
Early Nutrition Screening in ICU
00:23:26
Speaker
And could we start with the timing?
00:23:27
Speaker
You mentioned a little bit about it, but just to recap and emphasize, how should we think about timing?
00:23:32
Speaker
Yeah.
00:23:33
Speaker
Right.
00:23:34
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.
00:23:51
Speaker
And our electronic health records support this.
00:23:55
Speaker
You need an empowered nutrition service so that dietitians aren't seeing everyone.
00:24:03
Speaker
We want to save that skill workforce to see those at the highest risk.
00:24:07
Speaker
So we need health systems, nurses, unit clerks, patients themselves undertaking screening to identify those at risk.
00:24:17
Speaker
In our ICUs, all patients undergo typically a nutrition risk screen and an assessment prior to implementation of a nutrition care plan.
00:24:29
Speaker
And so assessment, we use the Canadian Nutrition Screening Tool in Canada.
00:24:34
Speaker
Two simple questions that all of you should be able to remember.
00:24:38
Speaker
You have to answer yes to both of these questions to screen positive.
00:24:42
Speaker
Have you lost weight without trying?
00:24:44
Speaker
And are you eating less than normal over the past two weeks?
00:24:48
Speaker
You answer yes to both of those questions.
00:24:50
Speaker
You screen positive for malnutrition and should be seen by a dietician to tailor interventions to meet your needs.
00:24:58
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.
00:25:11
Speaker
And so the dietitian clearly has a role in the intensive care unit to undertake initial screening and to...
00:25:21
Speaker
work with the team to ensure nutrition support is initiated.
00:25:26
Speaker
And so clearly enteral nutrition is the preferred route compared to parenteral nutrition.
00:25:35
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.
00:25:43
Speaker
It's not associated with poor outcome or, or, uh,
00:25:48
Speaker
less tolerance and it should be used.
00:25:51
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.
00:26:10
Speaker
And there's some difference between the European and the North American guidelines.
00:26:15
Speaker
And the goals are
00:26:17
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.
00:26:30
Speaker
And goals for protein provision are typically about 1.3 grams kilo per day.
00:26:36
Speaker
So the dietician should be on top of that.
00:26:38
Speaker
In our ICUs, we have our dieticians using special assessment techniques like body composition.
00:26:44
Speaker
or they're using indirect calorimetry to measure energy expenditure.
00:26:48
Speaker
So we have a better handle on what exactly the targets for a given patient are.
00:26:55
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,
00:27:06
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.
00:27:17
Speaker
And the dose for nutritional support usually comes in the ICU from our collaboration with our nutrition specialist.
00:27:26
Speaker
But could you give us kind of an overview of where we stand today based on evidence and
00:27:32
Speaker
Right, and so I kind of alluded to it.
00:27:34
Speaker
And so,
00:27:37
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.
00:27:50
Speaker
You, Sergio, sitting there, me sitting here, 25 calories per kilo is a reasonable guess.
00:27:57
Speaker
Listen, if I compare it to indirect calorimetry, I might be off.
00:28:03
Speaker
particularly if the patient is critically ill.
00:28:05
Speaker
But remember, that's a target for maintenance in the ICU, 20 to 25 calories.
00:28:11
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,
00:28:25
Speaker
that's rising out of proportion to creatinine, or challenging glycemic control.
00:28:30
Speaker
These are all features of metabolic intolerance.
00:28:34
Speaker
Your body's saying, wait, I can't handle those substrates.
00:28:38
Speaker
So the goal is 25 calories per kilo.
00:28:41
Speaker
That's challenging in the patient with obesity, where we often use a modified weight as opposed to their actual weight.
00:28:50
Speaker
We can base their energy provision on
00:28:53
Speaker
what their weight would be if their BMI was 25.
00:28:56
Speaker
So it's essentially a height-driven equation.
00:28:59
Speaker
And so the obese individual warrants special consideration, and we tend to underfeed in obesity.
00:29:05
Speaker
So a goal of 20 to 25 calories per kilo after day 3 to 7 is appropriate in the ICU.
00:29:14
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,
00:29:32
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.
00:29:43
Speaker
And so at that time, we can't hold back on energy and protein provision
00:29:49
Speaker
if that's what's deemed required.
00:29:51
Speaker
So in recovery, you may need 35 to 45 calories per kilo.
00:29:56
Speaker
And for rehabilitation, it may be even higher than that.
00:29:58
Speaker
And your protein requirements may go up.
00:30:01
Speaker
So it really depends on what phase of critical illness you're at.
00:30:05
Speaker
And we need to tailor the solutions to the patient.
00:30:08
Speaker
But a good starting point is 25 calories per kilo, 1.3 grams protein per kilo.
00:30:16
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.
00:30:32
Speaker
And in surgical patients, the guidelines typically suggest 25 to 30 calories per kilo, 1.5 grams protein per kilo.
00:30:41
Speaker
Excellent.
00:30:42
Speaker
Is there a difference in the mode of delivery in terms of bolus feeding versus continuous enteral feeding?
00:30:48
Speaker
Yeah, it's a really good question.
00:30:50
Speaker
And I do a lot of home enteral nutrition.
00:30:53
Speaker
I have 600 clients.
00:30:54
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.
00:31:08
Speaker
It also more closely mimics our feeding pattern when you and I eat.
00:31:13
Speaker
We don't eat continuously throughout the day.
00:31:15
Speaker
We might have breakfast, lunch, supper,
00:31:18
Speaker
And so that more closely feeds it.
00:31:21
Speaker
We use continuous feeding to get patients up to a goal rate.
00:31:25
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.
00:31:39
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.
00:31:49
Speaker
And so using low rates of continuous enteral nutrition is advantageous.
00:31:56
Speaker
And
00:31:57
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.
00:32:09
Speaker
But at the end of the day, convenience makes a difference, standards of practice, and when any ICUs and on wards,
00:32:18
Speaker
They'll have an enteral feeding manual, and that will specify what a standard of practice is for a given institution.
00:32:27
Speaker
And continuous feeding is a little bit more burdensome for the patient as we transition out.
00:32:34
Speaker
Bolus feeding is potentially desirable.
00:32:39
Speaker
This might be a good point for you to settle for once and all the gastric residual dilemma.
00:32:47
Speaker
I think every intensivist gets a call every day about this.
00:32:51
Speaker
Yeah.
Nasal Gastric vs. Post-Pyloric Feeding
00:32:52
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.
00:33:03
Speaker
It's become a habit.
00:33:04
Speaker
And, you know, what do you put your upper limit up?
00:33:06
Speaker
So there is no evidence that measuring gastric residuals impacts outcome or feeding.
00:33:13
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.
00:33:25
Speaker
Maybe we should have had an NG tube in that patient.
00:33:28
Speaker
But there's no evidence that suggests that measuring gastric residuals and holding tube feeds on that basis makes a difference.
00:33:38
Speaker
And this is still something that, despite guidelines, is very difficult to change at the bedside.
00:33:43
Speaker
They're patterns of practice, exactly.
00:33:48
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?
00:33:59
Speaker
Yeah, good question or good comment.
00:34:03
Speaker
Nasal gastric access is the easiest to get.
00:34:07
Speaker
It can be achieved with bedside placement.
00:34:11
Speaker
We shouldn't be using the standard 24 French nasal gastric tubes that are used for suction or 20 French tubes for suction.
00:34:19
Speaker
Those are hard on the nasal septum and they're not meant for feeding.
00:34:23
Speaker
So we should be using small bore silastic feeding tubes for patients.
00:34:29
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.
00:34:39
Speaker
If there's a patient who is on very high oxygen requirements with lots of pressure support ventilation,
00:34:48
Speaker
with high oxygen flow, I'm really concerned that aspiration in that individual might be a life-ending event.
00:34:55
Speaker
And so in that individual, intragastric feeding may be risky, and I might err on the side of feeding post-pylorically.
00:35:04
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.
00:35:22
Speaker
So the go-to should be intragastric feeding, but a small silastic, small-bore tube, 10 to 12 French,
00:35:31
Speaker
in patients who you have concerns about their ventilatory status or risk of poor gastric emptying, pursuing post-pyloric access makes sense.
00:35:41
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.
00:35:51
Speaker
That's been debunked.
00:35:53
Speaker
And so in the setting of pancreatitis, intragastric feeding is what is recommended.
00:35:58
Speaker
However, from a practical experience,
00:36:03
Speaker
Pancreatitis, particularly if it involves the head and the neck of the pancreas, can result in a gastric outlet obstruction or duodenal obstruction.
00:36:10
Speaker
So in that individual, post-pyloric feeding might be advantageous.
00:36:16
Speaker
An individual who has a requirement
00:36:22
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.
00:36:38
Speaker
Perfect.
00:36:40
Speaker
I wanted to talk about
00:36:43
Speaker
strategies to reduce harm and maximize the benefits of enteral and nutrition in our patients, looking at different categories.
00:36:51
Speaker
And we'd like to start with a metabolic, two issues that are frequent are proglycemia control and refeeding syndrome.
00:36:59
Speaker
Yeah.
00:37:00
Speaker
There's...
00:37:03
Speaker
Thanks to Gret Badenberg for having us all look at glycemic control.
00:37:07
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.
00:37:18
Speaker
And so I really like nice sugar.
00:37:20
Speaker
Blood sugars need to be between...
00:37:23
Speaker
eight to 10.
00:37:24
Speaker
I'm happy with a blood sugar less than 10 and using glycemic control protocols can be really helpful with this.
00:37:32
Speaker
And I think that needs to be done with the team, not advancing either enteral or parenteral nutrition.
00:37:38
Speaker
If you don't have glycemic control, blood sugars less than 10 makes a lot of sense.
00:37:42
Speaker
In my brain, this is linked to metabolic intolerance.
00:37:47
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.
00:37:58
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...
00:38:13
Speaker
electrolytes, minerals are the main intracellular cations.
00:38:18
Speaker
And if their levels are low in the intravascular space, that means they are very depleted into intracellular space.
00:38:26
Speaker
And that when we feed carbohydrate and insulin levels go up,
00:38:31
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.
00:38:48
Speaker
of refeeding hypophosphatemia in that individual who at baseline has low phosphorus, low potassium, low mag.
00:38:56
Speaker
You're also thinking, could their selenium be low?
00:38:58
Speaker
Could their thiamine be low?
00:39:01
Speaker
You feed them expectantly and don't advance carbohydrate delivery until you've got a handle on micronutrient stability.
00:39:11
Speaker
Excellent.
00:39:13
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.
00:39:22
Speaker
And when do we feed somebody on basal pressors?
00:39:25
Speaker
Could you comment on that?
Feeding Patients on Vasopressors
00:39:26
Speaker
Yeah, absolutely.
00:39:28
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,
00:39:42
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.
00:39:52
Speaker
And there is evidence that advancing to full rate enteral nutrition can precipitate.
00:39:57
Speaker
intestinal ischemia.
00:39:59
Speaker
Think about that cardiac output in the fed state.
00:40:02
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.
00:40:21
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.
00:40:35
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?
00:40:46
Speaker
And potentially nausea, vomiting, diarrhea are important.
00:40:50
Speaker
features of GI ischemia.
00:40:52
Speaker
They're symptoms that allow us to think, well, this is not being tolerated.
00:40:58
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.
00:41:10
Speaker
The SOFA score includes some liver function tests, but no GI signals.
00:41:16
Speaker
Maybe...
00:41:17
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
00:41:44
Speaker
a red flag that we might be precipitating ischemia.
00:41:49
Speaker
Excellent.
00:41:50
Speaker
You did mention aspiration risk and aspiration pneumonia is a concern we have obviously in the ICU.
00:41:56
Speaker
Any strategies to minimize this in addition to what you discussed?
00:42:01
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.
00:42:14
Speaker
And so, you know, appropriate trait care in patients who do have poor gastric emptying.
00:42:20
Speaker
And they may have high gastric residuals if you measure them.
00:42:25
Speaker
And so think of the person in ICU who would have poor gastric emptying.
00:42:29
Speaker
Typically, that's the diabetic.
00:42:31
Speaker
I'm not sure what it's like in your hospitals, but our prevalence of diabetes is
00:42:35
Speaker
in our hospitals now is about 14%.
00:42:39
Speaker
When I was in training in Boston 35 years ago, it was 4%.
00:42:44
Speaker
And so in certain parts of the US, I can imagine it's higher than that.
00:42:48
Speaker
Patients with poorly controlled diabetes and complications of diabetic gastroparesis are at that high risk.
00:42:56
Speaker
Patients who've had problems with gastric outlet obstruction.
00:43:00
Speaker
So those are the patients you want to look at for aspiration risk.
00:43:04
Speaker
and treat appropriately, appropriate suctioning and trait care is also relevant.
00:43:10
Speaker
I guess also being parsimonious.
00:43:13
Speaker
If you're running tube feeding at 100 an hour and they're vomiting, turn down the tube feeds.
00:43:18
Speaker
There is a lot of role for common sense.
00:43:21
Speaker
For sure.
Preventing Complications with Feeding Tubes
00:43:22
Speaker
And finally, mechanical complications are not uncommon.
00:43:26
Speaker
What are your suggestions or recommendations for dealing with either clogged feeding tubes or tube displacement?
00:43:35
Speaker
Well, you know, the smaller tubes you're using, they are at risk for clogging.
00:43:42
Speaker
And a simple method is to flush the enteral tube after administration of medications in particular and during tube feeding.
00:43:51
Speaker
So using liquid medications, recognizing that these small silastic small bore tubes are
00:43:57
Speaker
are not meant for medication.
00:43:59
Speaker
So an ounce of prevention for clogged feeding tubes by using liquid medications and crushing medications.
00:44:08
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.
00:44:18
Speaker
And these tubes aren't meant to be used to check gastric residuals.
00:44:21
Speaker
So avoiding that would be good.
00:44:24
Speaker
Perfect.
00:44:25
Speaker
As we close, are there any pitfalls, common pitfalls that we should avoid?
00:44:31
Speaker
And what would be your final pearls of wisdom on the topic?
00:44:36
Speaker
You know what, we have learned a lot over the past decade.
00:44:42
Speaker
And it's important to acknowledge
00:44:45
Speaker
wealth of expertise that exists within the ICU field to conduct really timely, effective, randomized controlled trials.
00:44:55
Speaker
But isn't it interesting after all these RCTs, we're still uncertain because the patients confuse us.
00:45:01
Speaker
So the first common pitfall to avoid is to try to meet nutrient requirements immediately in the critically ill patient.
00:45:10
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.
00:45:18
Speaker
It's the first few busy days in ICU.
00:45:21
Speaker
But by day three to seven, we should be thinking, do we need to be working more towards achieving
00:45:27
Speaker
energy requirements with their nutrition feeding.
00:45:32
Speaker
Don't be scared to use TPN.
00:45:34
Speaker
PN is not poison.
00:45:35
Speaker
And if there's someone who comes into your unit, it's the first to
00:45:39
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.
00:45:55
Speaker
So tailor the care to the individual patient and the patient with obesity and
00:46:01
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.
00:46:12
Speaker
And it's really clear in our general studies of critically ill patients.
00:46:17
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.
00:46:30
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
00:46:55
Speaker
The first question relates to books.
00:46:57
Speaker
Is there a book that has influenced you significantly or a book that you have gifted often to other people?
00:47:05
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.
00:47:13
Speaker
But one book that really stood out for me was called The Overstory.
00:47:18
Speaker
It was published in 2018 by a fellow named Richard Powers, who won the Pulitzer Prize for this work.
00:47:27
Speaker
And
00:47:28
Speaker
The Overstory is a story about trees.
00:47:31
Speaker
And this is the first time I had given trees a thought.
00:47:35
Speaker
And I think that it had me think about my environment more.
00:47:41
Speaker
So it was very compelling.
00:47:44
Speaker
It is a great read for anyone who wants to read.
00:47:47
Speaker
I agree.
00:47:48
Speaker
And when I read that book, the first thing that came to mind were the ants in Lord of the Rings.
00:47:55
Speaker
Yeah.
00:47:55
Speaker
So you read the book too.
00:47:56
Speaker
What did you think of it?
00:47:57
Speaker
Did it stand out in your mind?
00:47:59
Speaker
It did.
00:48:00
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?
00:48:11
Speaker
Highly recommended.
00:48:12
Speaker
So we will definitely link that in the show notes.
00:48:15
Speaker
The second question relates to changing your mind.
00:48:19
Speaker
Could you share with us something you changed your mind about over the last few years?
00:48:23
Speaker
Right.
00:48:25
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.
00:48:35
Speaker
I'm 62, and I'm actually thinking about how do I go slow as opposed to fast?
00:48:43
Speaker
And so that's been an evolution.
00:48:45
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.
00:49:00
Speaker
And so in our nutrition care practice, we're going to more...
00:49:04
Speaker
multi-chamber bag, what was previously known as pre-mix PN, and we're using a lot more peripheral parenteral nutrition.
00:49:13
Speaker
In fact, our intensivists during COVID used PPN as safe start nutrition.
00:49:19
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.
00:49:31
Speaker
It is not poison.
00:49:33
Speaker
We need to be thinking about other things.
00:49:35
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.
00:49:46
Speaker
That's not bad.
00:49:47
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
00:50:00
Speaker
It's got a longer shelf stability.
00:50:02
Speaker
It's safe.
00:50:04
Speaker
It results in less infectious complications.
00:50:06
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.
00:50:16
Speaker
We know that we're feeding enteral nutrition.
00:50:18
Speaker
We got a couple of products and we can give it to people and meet their electrolyte needs and macronutrient needs.
00:50:24
Speaker
I'm shifting my focus a little bit.
00:50:28
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.
00:50:43
Speaker
Perfect.
00:50:44
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?
00:50:55
Speaker
The short one is PN is not poison.
00:50:58
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.
00:51:09
Speaker
They still hadn't caught up with the PN is not poison.
00:51:12
Speaker
There's a little bit of confusion in the literature.
00:51:15
Speaker
And I think that with the excellent research work that's been done over the past decade, what we do know is that
00:51:25
Speaker
Few days, the acute phase of critical illness, patients who are fed what their nutrient requirements are do not do as well.
00:51:37
Speaker
So it's not the type of nutrition they're getting.
00:51:40
Speaker
It's the dose in that acute phase when it's not the biologic priority of the patient to be undertaking nutrient metabolism.
00:51:49
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.
00:52:00
Speaker
No, that clearly is not true.
00:52:03
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.
00:52:13
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.
00:52:21
Speaker
Exactly.
00:52:23
Speaker
Well, Leah, I really want to thank you for sharing your time and your expertise with our listeners.
00:52:28
Speaker
Look forward to having you back on the podcast.
00:52:32
Speaker
And definitely for those who have not read the overstory, highly, highly recommend it.
00:52:37
Speaker
Thank you.
00:52:38
Speaker
Thank you very much.
00:52:40
Speaker
Good.
00:52:41
Speaker
Thank you for listening to Critical Matters, a sound podcast.
00:52:45
Speaker
Make sure to subscribe to Critical Matters on Apple or Google Podcasts and share with your network.
00:52:50
Speaker
Sounds transforming the way critical care is provided in hospitals across the country.
00:52:55
Speaker
To learn more, visit www.soundphysicians.com.