Thermoregulation of the Neonate with Steve Falk

Ben Courchia, MD: Hello, everybody. Welcome back to the Incubator Podcast. We are back with this time a Tech Thursday. We are joined by Steve Falk from GE HealthCare. Steve, how are you?

Steve Falk: I'm doing great. Thanks, bud.

Ben Courchia, MD: For people who are not familiar with who you are, I'm just going to go through portions of your bio because your bio is quite extensive. You have over 35 years of product development, technical leadership experience in industry, both in startup environments and in large corporations. You're currently the chief engineer for the maternal infant care strategic business unit in GE HealthCare. You've been with the business for more than 31 years in a variety of roles and responsibilities, including senior engineer, engineering manager, lead program engineer, engineering director, CTO, and so on. You've been integrally involved with all phases of product development, including voice of customer, business development, business model generation, design verification, validation. And you also serve as the patent evaluation board leader. You have led the giraffe Omnibed and giraffe Panda platform product development efforts, which we are all very much familiar with. So it's very exciting to talk to you today about thermal regulation in the neonate.

Steve Falk: Thank you. Thank you.

Ben Courchia, MD: I guess my first question is, it's always very interesting to be able to speak to engineers because as physicians, as clinicians, we see things in a certain way, but as an engineer, what are the challenges that present themselves to you as you are trying to solve the problem of thermal regulation of a newborn?

Steve Falk: Oh, great question. So let me start with how we, as technicians, technical technologists, think about thermoregulation. It's really an energy balance of a particular control volume or control mass. This happens to be a premature baby, let's say. So when we think about that energy balance, we think, OK, how does the baby gain heat or gain energy? They do that by metabolism.

And so metabolism, as you know, glucose and oxygen come in, and energy in the form of ATP is produced. They're losing heat, they're losing energy in various ways. There's really four major ways, conduction, convection, radiation, and evaporation. Just real quick on those. Conduction is really a solid to solid thermal gradient. What that means is if the baby's lying on a mattress, it's going to lose heat or gain heat to the mattress. 

Convection, is where you're a solid, let's say the baby, in fluid, in air. So the heating, ventilating, and air conditioning, for instance, in the room, the baby can lose heat. What's interesting about this is it's not only proportional to the temperature differences, it's proportional to the velocity of the air. And most interesting, it's proportional to the surface area of the baby. The conduction one, by the way, is only proportional to the effective contact area.

So when you think about the baby lying on a mattress, it's not the whole surface area of the baby that's lying on the mattress. It's actually smaller, it's a smaller area than everybody thinks. So anyway, getting back to convection, proportional to velocity and surface area. With respect to radiation, it is the baby trying to lose heat to the next viewable solid. So what does that mean? I'm sitting in a crib and I'm losing heat to the walls, to the ceiling, to any solid that is that I can radiate to. What's interesting about that is it's proportional to the fourth power of temperature, as well as surface area. And then last is the evaporation, which is water loss. It's based on the humidity or the water concentration difference, as well as surface area. So when you think about that, you say, wow, I'm losing heat based on surface area, and my mass as a premature baby is small, my surface area to mass ratio is actually quite large. Mass is kind of directionally proportional to my metabolic energy and surface area is proportional to every which way I can lose heat. So as these premature babies are younger and younger, we think of them as engineers as a surface area to mass ratio and therefore the challenge is how do we keep these babies in a neutral thermal environment in where their comfort zone is so that they can grow, they can reduce any kind of caloric expenditure to getting warm, getting cold, and basically healing, growing, getting better. And so that's the challenge is that thermal management.

Ben Courchia, MD: What's interesting is I'm very interested in the historical evolution of thermal management of the newborn, and I think because it seems like a very simplistic problem, right? It's like, oh, baby gets cold, just wrap them up and keep them warm. And you look through history as how we've been trying to keep babies warm. And the range of ideas is just mind blowing. So obviously we have the late 19th century discovery of the incubator, inspired by incubators for chicks that were identified at the Paris Zoo. I've read reports of parents putting preterm babies in a box with feathers and putting it in the oven to try to keep a baby warm. So there, and we have mother skin to skin where we're trying to use another human being as a source of heat.

And so I think that when you're approaching this problem as an engineer and looking at all these attempts and all these iterations, how do you take the best of them and how do you create a solution that makes sense for the clinician at the bedside?

Steve Falk: Yeah, great. Also great question. And the one historical incubator you didn't mention that I always like to talk about is the one that was in the World's Fair where the baby is in a small partition above boiling water. And that boiling water, by the way, was heated with propane. So you can only imagine the fantastic issues that had.

Ben Courchia, MD: What? There's a lot of reports of burns in an attempt to try to keep babies warm. Sadly enough.

Steve Falk: Yes, yes, for sure. So I think how we think about everything you just mentioned was the thermal management has to be, it's a pretty tight control that we need to make. So there's evidence out there that suggests for premature babies that for every one degree centigrade, basically almost two degrees Fahrenheit, decrease in core temperature, there's a 28% chance more in mortality.

So we think of this sort of neutral thermal environment, this particular core temperature we want this baby to be is really plus or minus a half a degree or less in centigrade, so it's pretty tight. So when we start looking at different ways, as you mentioned, some of these, the feathers in the oven and all this other stuff, it has to be able to be controllable, and we think of the thermal time constant, so think of this, take your typical incubator even today.

And some of the challenges, okay, so we're gonna have a heater and a fan and it's gonna blow warm air over the baby in some fashion. And we need, because of we're trying to protect the brain and the neuroprotective care, the neurodevelopmental care, we want the sound in that incubator to be low. So I can't move air really fast, it's gonna be loud. So I gotta move it slow, but I gotta have the thermal time constant such that I gotta react to the baby getting cold or getting warm. 

So, the need to have that thermal time constant, that responsiveness, to be able to keep the baby within a half a degree centigrade and at the same time keeping it really low noise. So it's those kinds of interesting sort of requirements that almost butt heads against each other and finding that balance and that's where that simplistic problem becomes actually quite complicated.

Ben Courchia, MD: I think it's exciting to be able to talk to you because if you are, like me, interested in how things work, the idea of the giraffe Omnibed is something that is really, really â it's something that would pique your curiosity because it seems very straightforward, right? You have a temperature probe that's connected to the baby and an ambient temperature that is regulated based on the baby's temperature. But what's interesting about this is that it is not, these changes in temperature are not immediate, right? So they're progressive. And like you said, we have an imperative to try to keep the temperature of the baby within a tight range. And so when you are designing the algorithm that regulates the temperature of an incubator, how do you take all these parameters into account? Mainly how long is like, for example, a baby that is slightly has a temperature that's slightly higher than it needs to be, but it's suddenly decreasing. Is that pattern going to reach a point where we're crossing a certain threshold that leads to hypothermia? How quickly do we respond to changes in temperature? And how quickly are these changes in ambient temperature reflected on the baby? And how does that feedback mechanism work? I think I would love to hear more about that.

Steve Falk: Sure, sure. So for an incubator, so there's different algorithms, whether you're an incubator or in a warmer, radiant warmer, and for the Omnibed, there's actually both of those algorithms because the Omnibed can be an incubator or a radiant warmer. So let's take an incubator, for example. So, we, you know, the old version of incubators would basically turn on and off the heater, and maybe change the fan speed, but turn on and off the heater based on the baby temperature. And what happens is exactly what you said, which is how do you tune that algorithm to a particular baby who may have a slightly more sluggish way of changing temperature just naturally or a faster way depending on their gestational age or just in general their personality if you will. And so you end up chasing the temperature and what happens when you do that is that the heater will turn on and off and it will move the air temperature up and down as fast as it can and it generates this volatile kind of environment for the baby and it can generate some very bad things as you can imagine.

What we do at GE HealthCare, what the giraffe does, is what we call a cascade algorithm. So what we're doing is we're not directly changing the heater based on the baby's temperature or the baby's temperature changes. What we're saying is, we're gonna control the air temperature in incubator. What set point that we control that air temperature at could change slightly based on how the baby's reacting to it. And it kind of takes the time, thermal time constant, if you will, away and a little less relevant. It is similar to if you're in your home and you're slightly chilly and you go to your thermostat and you raise it up, let's say, a half a degree or a degree and then you kind of see how that plays out for a certain amount of time. And if that helped, fantastic. If you're still chilly, you knock it up another degree. So think of it as this constant or continual modification of the air temperature to keep the baby temperature where it's at.

That sort of sluggishness that we purposely put in there gets a more comfortable control. It allows the baby to change their temperature at whatever rate they're gonna change their temperature and that we would keep up.

Ben Courchia, MD: That's so interesting. As we were talking about these functionalities, I think some people that may be listening in the car may say, yeah, well, I knew how this worked out. I'm not very impressed by that. But I think sometimes what's lost on us is the degree of innovation that happens on a product or on a tool that we've been familiar with for many, many years. And I think as we are synthesizing a lot of the things you said, about the mechanism in which heat can be lost, about the mechanism in which an incubator functions, can you tell us a little bit about some of these other features that are present in an incubator that are allowing us to deliver the care we deliver on a day to day basis, all the while trying to keep that goal of maintaining normal thermia at the forefront? I'm thinking of portholes. I'm thinking of air boost, which I think many people are still not familiar with what air boost is.

Steve Falk: Mm-hmm.

Ben Courchia, MD: (12:49.627)

How do you, can you tell us a little bit about these different features?

Steve Falk: Sure, sure. So let's take the Omni-bed in the closed-bed mode or the incubator version, if you will. So what we do with our airflow in an incubator is we have what we call a double wall. So our doors or side panels have an inner wall and an outer wall, if you will. It's kind of like a double pane glass in your house. And the airflow goes up that through those walls. And there's a reason for that, couple reasons actually. Number one is that the air can actually be warmer because the baby can't actually feel that air. It can't put their hand over the vent, if you will, and get hurt in any way because that air can be a little hotter because the baby can't touch that air. And it comes out kind of at the top of the door. It, at the same time, is actually warming that inner wall. So when we talk about our radiant energy, that baby is looking at the next solid. Well, that next solid is the inner wall. 

So now, the room temperature, if you will, has no, has less relevance to how the baby's going to either be warm, be cool, it's really in our control. We think about portholes. Now, so when we talk about interventions, clinicians are in the portholes, as you know, a lot, and so we've designed the portholes such that they're little tunnels, if you will. So those portholes do not in any way break up that inner wall airflow.

So if there were, for instance, if there were just portholes there and all we did was open the porthole doors, a lot of that airflow coming through the inner walls would try to escape. And if it tried to escape into the room, it's not gonna draw negative pressure in the incubator, there's gonna be air that's going to displace it. Well, that air that's gonna displace it will be room air. So now I'm gonna get cold in my incubator. So we have these tunnels, they're gaskets that go around the porthole. And so what happens is you open the porthole,

Those open portholes are not in any of the forced convection that we are putting into the incubator. So the only escape of that warm air is just that natural sort of mixing that happens very slowly and it's not actually very effective. So we really don't have any significant temperature drop when you open portholes. That was done very purposefully. When it comes to the air boost you mentioned, so we have an ability to push a button and boost the air. What does that mean? It changes the fan speed such that when I, for instance, open the door of the incubator, you could feel the air coming up because that's the vent that's gonna come up. And when you boost that air, it's very similar to, I'm sure you've gone into a supermarket or some sort of store where they're trying, you feel this burst of air as you're walking through the entrance. That air can actually divide warm air and cold air and keep those divided. They, it's very difficult for that air to kind of cross the air curtain. The faster the air, the better.

Ben Courchia, MD: If the flow is fast enough, then it acts as a barrier. Got it.

Steve Falk: Correct, correct. And what we also do is there's a little feature inside of that incubator that when you do that, when the door is open, it kicks the air about four or five degrees inside the incubator, slightly off a vertical. So what we're making sure, not only do we have an air boost curtain, we have an air curtain, we have an air curtain that is leaning into the incubator because we don't wanna waste that beautiful warm air and put it into the room. And so those are the kinds of like, little features that I think clinicians may not either know about or maybe appreciate that we spent time doing to make sure that any intervention of cares or anything into the baby that the baby gets the best normal management they can get.

Ben Courchia, MD: Yeah, and these are the kinds of things where if you're a provider and we do get, there's always some form of in-service happening in the unit. And I think I'm talking to the doctors and providers here. When people from GE come to go over some updates or whatever it is about beds, even if you're a clinician and say, oh, that's for the nurse, that's not for me, go and listen, because that's how I find out. I found out about all these different features and I was like, holy smokes. I never knew about this. Nobody told me that I should have to press air boost when I'm going into the, into the incubator. 

That's super helpful. Can you tell us a little bit as we're discussing all these features at the bedside, how does feedback from your users, from the clinical team, how does that play a role in how you iterate on the different products?

Steve Falk: Huge role, huge role, Ben. So we have a clinical staff in the maternal infant care business, as well as we have tremendous key opinion leaders and clinical partners out in the world. And we're constantly going and having those conversations. Those that are listening are probably laughing that maybe we do that too much and bother them a little too much. But anyway, we see them at conferences, we call them. And that feedback is fantastic. As a matter of fact, in developing the giraffe OmniBED and that platform, we probably talked to more than a thousand clinicians all around the world as we were developing it and we continued to do that. It wasn't that we scoured the earth and got all this feedback and then just developed this product and launched it. It was continual feedback from focus groups to conferences to road shows to conversations to studies all throughout the development and even as we were launching the same thing. And to be honest with you, even post-release, now it's in the market. We continue to get that feedback so that we can iterate and innovate on what's next and what is the next incubator and what should we be paying attention to and all of that. And we love not only speaking and having these discussions with these clinicians, but they learn, we learn. 

Look, diversity in the room is huge, and it brings the best solution possible, as well as we believe wholeheartedly that the clinicians can be part of this design process.

Ben Courchia, MD: Something that's interesting sometimes in the clinical field is that we feel as providers wrongfully that we are finding best use for tools that we have at the bedside and forget that we are aligned with the team that developed the tool. And I think to that end, a topic that we've discussed a lot on this mini series has been how there are various aspects of maintaining thermal regulation that are very different from one another most notably in and around the time of birth when we're talking about the concept of golden hour. And so I am wondering if you could share with the audience a little bit, how has this entity of golden hour and the challenges that it presents influenced or sparked any design or functionality of the tools that is developing to address thermal regulation in a new one.

Steve Falk: The golden hour is an interesting one because there's sort of many different things that are happening within that golden hour evolution even currently from delayed core clamping to all sorts of other things that are going on. And so we still step it back to the science and the physics. So this baby comes out, look, this baby was what, 37 and a half, 38C inside of mom. They come out to a what, 22 degree room wet.

That's incredibly impactful, as you can imagine. Thank goodness we don't remember that experience. And so we think about the four heat partitions. So first of all, the delivery room temperature. Maybe that should be higher, and I know that there's a strong indication that that's the case. Obviously the radiant warmer brings a tremendous amount to that table, so it's infrared energy radiantly coupling to the baby that's trying to balance all the ways the baby's losing heat, you know, you hear about sort of very premature babies, some of these extremely low birth weight babies being put in plastic bags. What does a plastic bag do? It, first of all, reduces the evaporative heat loss tremendously. It actually reduces a lot of the heat losses, radiantly, convectively. There's no air flow really in the bag. So the bag, as much as it may seem a little primitive to hear about that, is actually amazing to benefits.

And so we think about that as we start innovating kind of where we want these microenvironments to go within the golden hour. And thinking about delayed cord clamping, you know, it's funny. We had, I've had conversations with some of the clinicians about just the delayed cord clamping. So when the cord is intact, for instance, for the first, let's say, couple minutes, is the baby gaining heat or losing heat because the cord, you know, the placental blood is still transfusing into the baby.

And the answer is we don't know. And the answer is it's controversial and the literature would suggest both ways. And what it does, it depends on a tremendous amount of things from gestational age to perfusion in the core, to even the heart rate and sort of the blood flow, if you will. And so we're looking at those kinds of things and how do we get the golden hour to be a smooth thermal sort of transition, if you will, because at the end of the day, the thermals are tremendously important, but airway breathing and circulation is obviously more important, and we don't wanna sacrifice one for the other.

Ben Courchia, MD: That's great. I mean, as we are getting close to the end of this chat, I'm hearing you speak about all these things and you can definitely hear a passion behind all these tools and all the development that goes behind it. And you have an impressive resume. I am wondering, you could work in a variety of industries and yet you are here working at GE for maternal and newborn health.

What kind of satisfaction does that bring you and what keeps bringing you back to this field day in and day out?

Steve Falk: You know, I get asked that a lot, especially when you're at any place 30 plus years, you get asked a lot. Honestly, it's the babies. It's, you know, you save one life, you save the world, right, so it's the babies. It's the clinicians out there, they're saints, and I just love working with them. It's obviously the team that I work with and in our products, but honestly, it's waking up and saying, you know, how am I putting something, how personally, and our team, how are we making the world better in some way?

And the baby business is such a fantastic business. There's been plenty of opportunities to go elsewhere and I just love it. It's just, it's very personal and it's very, it bleeds into your sort of your personal life. And I couldn't think of working anywhere else.

Ben Courchia, MD: Yeah, I think it's important for me to ask that question because as clinicians, as frontline healthcare worker, we can sometimes see a company, we can see a logo and think really like a faceless corporation. But I think we should be reminded that behind these tools that we use, there are people that are people that have and that share the same dedication and passion for newborn health. And I think in this day and age to see someone working at a company for over 30 years, it's an outlier. It's people tend to move and seek whatever compensation package is more enticing somewhere else, you know? So, uh, I think, I think it's, it's so refreshing to hear your perspective and, and to hear this dedication, uh, to, to newborn health.

Ben Courchia, MD: There's a lot of, you're an engineer, there's a lot of tech and technology is now making the rounds in the news, and it's something that we tend to read about every single day. I am wondering if there are any things coming up on the horizon that you are looking at, and you are just getting super excited about when it comes to the tools that we talked about, when it comes to the care of critically ill newborns.

Steve Falk: Yeah, there's actually a bunch of technologies out there. I know there are everything, and it sort of goes throughout the whole spectrum. I know you guys are probably, anybody listening has probably seen some of the literature on that's happening at the University of Pennsylvania with the artificial womb, with the lambs, and yes.

Ben Courchia, MD: Yeah. With the bio bag, I think that is something that had made the rounds in USA Today where they basically put fetal lambs in this, literally looks like a plastic bag full of fluid but basically creating an artificial womb where they could potentially maintain a fetus for X amount of weeks. And that, I think that was about like a year or two ago, I think, right? Yeah.

Steve Falk: It was, they're still working on it. And I'll tell you, I don't know that I yet have, what my opinion of, is that really the ultimate future? But what I love about the fact that they're doing that is that there'll be some amazing technologies we're gonna find along the way. And that's what excites me about going, kinda going for the true blue sky, whether we ever get there or not, whether that's technically gonna, acceptable or technically gonna happen, going to, you know, acceptable. But at the end of the day, some of these technologies along the way, how what we're going to learn about the survival and actually it's not even so much survival, it's kind of the morbidity and the ability to have a fantastic trajectory of health for these 22, 23, 24 week kids. What we're going to learn from this journey is going to be fantastic and I can't wait.

Ben Courchia, MD: That's fun. That's exciting. Steve, thank you. Thank you so much for making the time to be on with us today. I think it was a very enlightening conversation. I think everybody is going to leave this podcast thinking, I never knew that my incubator did all these things. So I'm sure there's going to be a lot of calls to GE to have some rep come and show us around the incubator once again.

And we're very excited about what you guys are gonna come up with in the future. I think the dedication you guys have for newborn care and for maternal health is impressive, and I think that's gonna translate into more innovative tools. So thank you for all the work that you do. Thank you.

Steve Falk: Thank you, thanks for having me.