Professor Steve McClave - Louisville Kentucky
MB: We're at the ASPEN Congress 2019 here in Phoenix, Arizona.
I'm here with Professor Steve McClave from Louisville Kentucky, where he is specializing in ultrasound and particularly in gastroenterology and has a long sparkling history in nutrition.
We heard a presentation from you yesterday around the Target Trial that was published by the ANZICS group last year. You were mentioning that this could have a changing impact on the prescribing for patients in the ICU. Would you like to elaborate on that?
Steve: Yes. This trial is incredibly deceptive. When it first came out, 1 1/2 cal/cc versus 1 cal/cc formulas, I thought why they are spending a lot of energy and effort studying this? And then to get the study results it has, look and dig deep into this trial it was so well done. The message has so many incredible implications for changing practice, that I just had a complete turnaround about the value of this report in the literature. Basically, the idea of the trial was if getting the goal's important, a real neat, simple strategy is just simply use a more concentrated formula. That's what they did. They were the first ones to show that with a concentrated formula you could meet energy requirements easily. The findings were that it didn't change outcome, it didn't give them any advantage.
MB: Just energy.
Steve: Right. Both groups had the same protein. A group that got the routine formula that ended up at maybe 75% or about 70% of requirements did just as well. It has implications-- you have to ask yourselves, "How could those results be explained?" One of it may be that the amount is less important than timing. Get the feed started early, that's more important, and the total amount, you just gotta get in the ballpark, maybe around 70-80%. It could mean that the calories aren't the issue, it's the protein that's more important. Focus more on getting to the protein goal, and the calorie goal is less important.
It could mean that in critical illness where you have mitochondrial failure, they are unable to utilize the energy we're giving them. Why pound them with something they can't utilize? That could actually act as a stressor. Another reason is that the timing is important, but just giving enteral or parenteral calories and protein is not enough. That we need to add additional strategies to actually change outcome like prebiotic fiber, probiotic therapy, blenderized whole food formulas that will get down to the colon where the microbial burden is, giving agents to bind pathogens, like bovine-derived serum derived immunoglobulin.
Then the last thing could explain this difference is, refer to the phases of critical illness. In this Target Trial, the average duration of feeding was six days. That is still within the acute and immediate post-acute period. During this period, maybe getting to goal calories is not the point. It's getting it started, bathing the GI tract with nutrients and then when they get past that point in the recovery, you would ramp up to goal. This study has tremendous implications, to me it suggests that we don't have to have an exact measurement of requirements. That we get in the ballpark, we ramp up slowly, focus a little more on protein, rather than calories per se. Start thinking about additional things we can add to nutritional therapy that will truly change outcome.
Meg: You've got a tremendous knowledge and expertise, and you've spent a lot of years focusing on this area. How do we translate this to the clinicians that don't have this level of knowledge you have? What do we do from here?
Steve: Guidelines help a lot. Sit down as a group at your institution and discuss these findings. Start with the guidelines, and then dig out the individual trials. Then monitor tolerance as you start feeding, decide as a group where you want your protein goals, and what the calorie goals are, and how quickly you advance. Then monitoring part is important, because you can't push it hard if they're on pressure agents. You got to watch top GI tract and tolerance. You've got to make sure the phosphate doesn't drop out on you. Then you have to back off, because of fear of refeeding syndrome.
You just try to incorporate these things into practice. It helps to sit down as a group, and say, "How do we interpret these guidelines? How do we interpret these studies?"
Meg: Everybody needs to know about this paper?
Steve: This Target Trial is incredible. It's incredibly well done. Fabulous group. We're going to hear more from this group in future, but this does change practice.
Meg: Can I ask you, how will it change practice in your day to day work?
Steve: I'm a big car head, I love everything about cars. I would love to argue that you got to measure and know exactly where the requirements are at all times. This has shaken that belief. I think I can use a weight-based number and just get around 70 to 80% of that over several days, and I'm probably okay. I'm going to focus on protein a little more. I'll use a weight-based equation for that, but the precision is probably not as important.
Meg: It's ever advancing, the world of nutrition for the critically ill.?
Steve: Yes.
Meg: Thank you very much.
Steve: All right.
Meg: It was a pleasure to speak to you.
Steve: I enjoyed it. Thanks.