#465 - [🫀 From The Heart] - Bringing NICU Feeding Practices to the CICU (ft Dr. Elgersma)

Hello friends 👋

In this episode of From the Heart, Drs. Nim Goldshtrom and Adrianne Bischoff talk with Dr. Kristin Elgersma, a nurse-researcher whose path into neonatal nutrition began at her son's bedside in a cardiac ICU. A former concert pianist turned nurse-researcher, Kristin asked a question no one had: does human milk change outcomes for babies with congenital heart disease? Her multicenter PC4 study of day-by-day data from over 800 infants across 25 centers found no link between human milk and NEC, though bovine-derived formula or fortifier tripled NEC risk within five days, while higher human milk intake meant roughly nine fewer hospital days. They cover lactation support, donor milk gaps between NICUs and CICUs, and practical next steps.

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The articles covered on today’s episode of the podcast can be found here 👇

Elgersma et al. Human milk feeding, fortification initiation, and clinical outcomes in neonates with critical congenital heart disease: A multi-institutional study. medRxiv 2026. DOI 10.64898/2026.08.20.26360934 (preprint, no PMID)

Elgersma et al. Human milk feeding and direct breastfeeding improve outcomes for infants with single ventricle congenital heart disease: Propensity score-matched analysis of the NPC-QIC registry. J Am Heart Assoc 2023. PMID 37642030

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Short Bio: Dr. Elgersma's research centers on human milk feeding and breast/chestfeeding for infants with critical congenital heart disease (CHD). Her work has been among the first to implement machine learning techniques and methods for causal inference in CHD nutrition research, and she is currently focused on developing personalizable, human milk/breastfeeding-based interventions that can improve the growth and neurodevelopment of these vulnerable infants. Dr. Elgersma transitioned from an academic career as a pianist into nursing research due to her own experience as a parent of a child born with critical CHD.

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The transcript of today's episode can be found below 👇

Dr. Nim Goldshtrom (00:01): Hello everyone, this is Nim Goldshtrom, and welcome again to From the Heart, our cardiovascular and congenital heart disease focused portion of the Incubator Podcast. I'm joined by my wonderful co-host, Adrianne, if you want to introduce yourself.

Dr. Adrianne Bischoff (00:14): Hi everyone. For those just joining our podcast for the first time, I'm Adrianne Bischoff. I'm one of the neonatologists at the University of Iowa, and I'm here because I'm also a neonatal hemodynamics expert. So I intersect with Nim more in the normal heart, while Nim can stay with the broken hearts.

Dr. Nim Goldshtrom (00:33): Fair enough, right? But between broken and normal, we get the whole spectrum of cardiovascular care. We're excited to try yet another format given all the positive feedback we've had with both journal club and our interesting case series. We're really pleased to be joined by a leading researcher in the field who I think is going to cross a lot of domains between those of us who care for kids with normal and broken hearts, and the aspects of nutrition. Kristin Elgersma, thank you for joining us today for our first interview.

Dr. Adrianne Bischoff (00:58): Crossing the domains of neonatal topics into the cardiovascular space.

Dr. Kristin Elgersma (01:03): Thank you so much for having me.

Dr. Nim Goldshtrom (01:10): We've invited Kristin because she's just undergone a very extensive and ambitious project in nutrition, specifically focused on human milk and human milk exposure in neonates with congenital heart disease, and is on her way to producing publications on what she's learned across various children's hospitals doing congenital heart disease care. Thank you for taking the time to talk about your research.

Dr. Kristin Elgersma (01:35): I'm excited to talk about it. It's been a great project.

Dr. Nim Goldshtrom (01:40): A little disclosure: I'm well aware of this because I contributed to this project with our center's data, so that's my bias here, although no financial disclosures to make. Kristin, tell us how you got into this space. I think you've taken a unique road into medicine and research, and we'd love for our audience to hear the different pathways people take to get here.

Dr. Kristin Elgersma (02:05): Yeah, it's definitely not been a straight path. I never expected I would be doing this kind of work. I had a totally different career. I have a master's and doctorate in piano performance, and I was on the tenure track in piano. Then in 2015 I had a baby with congenital heart disease, and that changed everything for me. It was a postnatal diagnosis, so very unexpected. Suddenly, as you're well aware, you're sitting in the CICU (Cardiac Intensive Care Unit) day in, day out. I was academically inclined enough that I'd sit in the back and look up studies to try to figure out what was going on. I found it fascinating, and I was drawn right into the whole world of congenital heart disease.

Dr. Nim Goldshtrom (02:56): That is quite a story. I don't know that I've ever heard a parent so fascinated by congenital heart disease that they literally made a career change. Kudos to you for becoming so involved and seeing this as an opportunity, not just something to experience with your child and family. This is incredible. Not to belabor it too much, but the pivot itself, making a career change, entering medicine and nursing and clinical care, going from school to the bedside and into research.

Dr. Kristin Elgersma (03:20): It took a little bit of time to make that pivot. My son unfortunately didn't make it through his second surgery, when he was sixteen months old. I'd been thinking about a change, but after that point I felt more compelled to make a firm decision. One of the things that was very important to me as a parent was feeding. That's how I got into this topic.

Dr. Nim Goldshtrom (03:40): So sorry.

Dr. Kristin Elgersma (03:44): Being part of the social media groups parents are involved in, I saw I wasn't alone in that. After my son died, I decided to do an accelerated nursing master's program, so I moved to the Twin Cities. I was in Hawaii at the time, so that was a big shift too. I moved from Hawaii to Minnesota, doing things backwards. I did the master's of nursing program, and I was always very interested in research, so I intended to end up there in some way. I worked a bit at the bedside, then did a PhD.

Dr. Nim Goldshtrom (04:15): Wow, that's quite the course. During the bedside years, did you spend time in the NICU (Neonatal Intensive Care Unit) and the CICU, or both?

Dr. Kristin Elgersma (04:25): I was at Mayo Clinic, and at the time they had a unique setup where adult and pediatric cardiac were all in one unit. So I was working with adults, and they train you on adults first, I think, a little safer maybe at the beginning, then you move over to pediatrics. That's also when COVID hit, so it was a bit of a unique experience. But then I moved pretty quickly back into school.

Dr. Nim Goldshtrom (04:50): This sounds like three lifetimes, considering COVID. What a depth of life experience and passion to keep going through these things. It's funny to hear you say they train you on adults because it's "safer," but I don't doubt it. We don't say it all the time, but they are scary. The margins are just not

Dr. Kristin Elgersma (05:10): Feels like it. I mean, that's my suspicion, I'd imagine.

Dr. Nim Goldshtrom (05:16): Babies, babies are scary.

Dr. Kristin Elgersma (05:19): Yeah.

Dr. Nim Goldshtrom (05:21): They're just not the same. But this is incredible. All the kudos to you for staying with this and finding something out of something so challenging and difficult for so many families, something you were able to turn into a positive for yourself and potentially for a generation of children. I think that's what a lot of us do this job for, whether it's a personal experience or seeing what we can do for individual families, and how that translates into

Dr. Kristin Elgersma (05:50): Mm. Yep.

Dr. Nim Goldshtrom (06:17): a special thing, right? It's one of the things that keeps us going despite documenting in the medical record and billing and all the day to day difficulties, is those kinds of moments. So all the accolades to you for going through this. We'd love to hear about the incredible work you've done, and as someone who contributed to your project, I'm curious about where it started.

Dr. Kristin Elgersma (06:40): Yeah.

Dr. Nim Goldshtrom (06:46): You did a multicenter study with many, many centers, which has its own challenges, and I'd love to hear about it. But what was the one thing that made you want to focus on this area? What was it, from your personal experience with feeding and the care you saw, that led you to focus so much on human milk? We're all neonatologists on this call, and not a day goes by where we're not talking, advocating, and figuring out how to get human milk, whether maternal or donor, into our babies at every step of the way.

Dr. Kristin Elgersma (07:15): Well, it's interesting. I did have my own personal experience, and I really wanted to breastfeed my child. It didn't really happen, but in retrospect, with a bit more support, it certainly could have and should have. He had double outlet right ventricle (DORV) as his primary cardiac disease, but he was actually quite healthy in spite of that. He had no issues with oral feeding, no issues with weight gain, seemed very normal in that regard. But I did end up pumping exclusively for a year. Having that experience, knowing what a drain that was, literally and figuratively, I had a lot of regret about not being able to directly breastfeed. That would have been very meaningful to me, and I saw that across parents in social media groups. It seemed like something that was very important and under-supported. I started looking into the research and found there wasn't much at all on this topic in infants with CHD, lots in the NICU of course, so I became curious. I remember one specific paper, a case study of an infant with single ventricle congenital heart disease who had been able to directly breastfeed, and they

Dr. Kristin Elgersma (08:40): traced the process of how that worked in their clinic. There was a line something like "to our knowledge, this is the first report of an infant with single ventricle directly breastfeeding." I was on these social media groups and saw it all the time, so parents were doing it, but it wasn't in the literature. I thought that would be a good place to start.

Dr. Nim Goldshtrom (09:05): Those kinds of cases and experiences are usually what drive change. Thinking about it today, we have two-ventricle repairs who, once they're de-intensified and breathing on their own, off things like CPAP (Continuous Positive Airway Pressure) and high flow, are just working on the endurance to feed everything by mouth. If the parents are interested and the baby is able to, it's not something we think about anymore. But I can see a decade ago, with the high-risk nature and the growth requirements, how that could have been a problem. Adrianne, thinking about the micropreemies and extremes of prematurity you care for, at corrected gestational age for discharge, are you sending these kids home on twenty-two calorie NeoSure feeds for growth? Do they have any opportunities for breastfeeding? What are you doing for micropreemies who are ready for discharge but also have growth limitations, where you have to balance the nutritional components against the activity of a normal, term, corrected kid, which would be going to the breast, even if the caloric requirements aren't optimal?

Dr. Adrianne Bischoff (10:10): I'm not fully versed in our statistics on this topic, but a lot of our babies go home on fortified feeds, a combination of human milk and formula. I get the sense that especially the micropreemies who've been in the NICU so long, there's probably not as much support as there should be to establish breastfeeding later in the course. There's a very clear

Dr. Adrianne Bischoff (10:41): progression on how to feed orally, cue-based, a number of times a day where you can offer feeds, but it's not that common that I see these tiny preemies truly breastfeeding by the time they leave. Part of it is the perception of the need for additional nutritional support with fortification, and part of it, I think, is that moms have just pumped for so long they want to get out of there as quickly as possible. So we do whatever the protocol is, whatever's easier, cue-based bottles, and that's kind of it. That unfortunately happens. So it's actually refreshing to hear about this more, because it's something for me to think about more in my own practice.

Honestly, it would seem easiest for everyone, and probably developmentally most appropriate, to be able to transition kids from periods of critical illness back to the most natural way of getting nutrition, which is going to the breast almost on demand when they have the endurance for it. But we're not really close to that, and your study is going to highlight some of those percentages. We should come back to this toward the end, but I want to give you the opportunity to tell us about the journey you went through, and the questions you were asking in the study you undertook with all these centers.

Dr. Kristin Elgersma (12:15): That was built on some previous work I'd done using the National Pediatric Cardiology Quality Improvement Collaborative (NPC-QIC) registry. For my dissertation, I did a registry study looking at single ventricle infants and human milk and breastfeeding. The outcomes we looked at were necrotizing enterocolitis (NEC), sepsis, length of stay, and infection, the kind of classic human milk related outcomes. We did find substantial associations between increased human milk, increased breastfeeding, and better outcomes across all of these, mirroring much of the NICU literature. But what I was curious about, and what prompted the study we're discussing today, is that with registry data you have one time point you look at: what's happening at discharge, what happened preoperatively, what happened at the time of readmission for stage two palliation. I was curious whether dose mattered, what was happening day by day with daily, detailed, granular nutrition data, and whether these findings would still hold up if we drilled down further.

Dr. Nim Goldshtrom (13:20): No, no, you're underselling how granular this was. Please describe the granularity of what you asked all of us to contribute.

Dr. Kristin Elgersma (13:30): Everybody who collected data says the same thing, it was very granular. I'd heard Chris Mastropietro, who leads CORE PCICS, collaborative research from the Pediatric Cardiac Intensive Care Society (PCICS), present on it. It's a collaboration of many sites across the country who come together to do these more detailed,

Dr. Kristin Elgersma (14:12): granular studies using electronic health record data. I proposed a study through them, was given a lot of support, and 25 sites agreed to participate. I asked for 28 days of data, I was thinking maybe 60 would be more interesting, but I got talked down.

Dr. Nim Goldshtrom (14:35): You got talked down to twenty eight days. That's impressive.

Dr. Kristin Elgersma (14:42): One thing I didn't realize is that I'm at the University of Minnesota, and we have really good informatics support, so it doesn't matter if I ask for 28 days or 10 years, it's one click and I get an Excel sheet. I didn't realize not everybody has that. That's how I got talked down to 28 days, because I quickly realized many sites would be collecting this data by hand. They were gracious enough to collect the first 28 days of nutrition data:

daily volumes and types, so maternal human milk, donor human milk, or commercial formula, fortification data, when it started, what type it was, and then roughly every four or five days we asked for that information again. We also asked what route it was, tube, bottle, or breast,

and whether it was bolus or continuous. So we got all of that data for the first 28 days from about 830 infants across 25 sites.

Dr. Nim Goldshtrom (15:49): It's an impressive undertaking. And as someone who had to do it, we have some IT support, but I still did a lot of manual review. You guys had every three hour feed cataloged in all this granular detail. It's a wealth of data, so congratulations. It's wonderful to hear, PC4 (Pediatric Cardiac Critical Care Consortium) is the CICU's version of something like VON (Vermont Oxford Network) or CPQCC (California Perinatal Quality Care Collaborative), a rich data source you can build off of, and you've done an amazing job using their resources to build a reasonable project and get such a great return, 800 plus babies. It's incredible. So now you have all this rich data, what did you learn about how we're doing in terms of human milk, breastfeeding outcomes, and their effect on neonates with congenital heart disease?

Dr. Kristin Elgersma (16:45): We had two primary aims. The first was similar to my dissertation work, looking at the effect of human milk percentage, the percentage of the enteral diet that was human milk, and its relationship to NEC, our primary outcome. Sepsis, a composite infection variable, and length of stay were the secondary outcomes.

I want to say a bit about the sample too, because I think it relates to what we found. The inclusion criteria were infants who underwent neonatal surgery on cardiopulmonary bypass, with some exclusions. If they weren't able to separate from bypass and were on ECMO (Extracorporeal Membrane Oxygenation) postoperatively, those infants were excluded. We excluded infants who didn't have seven days of enteral feeding

during the neonatal period, so some of the sickest infants who never fed enterally weren't in the sample. And we excluded infants with extracardiac anomalies that would impact feeding, like a cleft palate or gastrointestinal anomalies. When we looked at the percentage of human milk received, maternal or donor, I have to mention donor milk

Dr. Kristin Elgersma (18:02): comprised only 3% of the neonatal nutrition, so it was very low. I know everyone always asks about donor milk, and there really wasn't much. But human milk broadly and NEC: there was essentially no association between the percentage of human milk and NEC. There are always challenges, nutrition research is so hard because the question is

Dr. Nim Goldshtrom (18:25): Interesting.

Dr. Nim Goldshtrom (18:30): Yes. You have babies who developed NEC and babies who didn't. The ones who develop NEC at a certain point basically get censored out because they stop feeding at the time of diagnosis. The babies who didn't are going to continue getting nutrition.

Dr. Kristin Elgersma (18:45): So we had to do a sort of pseudo-matched population, where we matched each NEC case to 10 babies using propensity score matching, and then censored those babies' nutrition data at the same date as their match. So there are some limitations still, but even so, we saw a pretty high percentage of human milk in both groups, over 70%, and no association with NEC.

Dr. Nim Goldshtrom (19:10): I think getting around the statistics is one of the main points here, finding a way to do the censoring, the propensity scoring, is a great approach. Going back to the donor milk point, that's really interesting to me, because I think that's one of the first areas you bring up that shows the opportunities here. I'm biased as a neonatologist who does CICU work, but one question that comes to mind: babies make up such a large fraction of CICUs, anywhere from 10 to 30, even 40 percent of the time of inpatient admission, and yet neonatal care, especially perioperative care, is recognized as an important subdomain discipline. It's helpful for CICU staff who don't do this often to have that input, but not every place does it the same. You mention only 3% use of donor milk in your study.

Dr. Nim Goldshtrom (20:16): You surveyed 25 centers from PC4, these are almost certainly not the small centers around the country, you're probably capturing major centers. I'm guessing here without knowing them exactly, but I can't imagine that between 2020 and 2026, only three percent of NICUs at these centers have donor milk programs. So this is a potential bridge that, even at centers currently using it, isn't being crossed, and it's a real opportunity for kids who, for purely programmatic reasons at their center, aren't getting these supportive services, not because the center lacks it, but because of where they're housed. I'm making assumptions here, but it would be a great opportunity to get more neonatal integration, not just consultation, for these kids, who because they're living in the CICU, don't get the benefit of all these neonatal services we're so familiar with.

Dr. Kristin Elgersma (21:10): Yeah, and just to clarify, this is some of what I'll get to later regarding the site survey. I think there are centers that have donor milk available but it's not being used, centers that don't have it available at all, and centers where it's differentially available between their NICU and CICU. We found that only 60% of the centers have a donor milk protocol,

but even at centers that have a protocol, usage was very low.

Dr. Nim Goldshtrom (21:40): So this clearly is an opportunity for those listening at these major centers, it's a low hanging fruit for how you can impact care right where you are, from studies like this showing the potential of offering these opportunities. So while human milk overall wasn't a significant factor for NEC, you did find some other positive findings on risk for this population.

Dr. Kristin Elgersma (22:04): Yeah. When we had this surprising finding of no relationship with NEC, I was curious, so I wanted to look in more detail at the nutrition of each infant who developed NEC, since we had this daily, detailed, granular data. I'm very into data visualization, so I made a little figure for myself, and when I looked at it, it was interesting: a lot of these kids had a lot of human milk, but then they'd start fortification, and very shortly after, a NEC diagnosis. Or they'd have all human milk, then get one day of formula, and shortly after, a NEC diagnosis. We tried, with the statistical limitations we had, to find a way to quantify that difference, and with a matching strategy, we looked at the relationship between first initiation of formula or bovine-derived fortifier and development of NEC, and found it was associated with three times greater risk of NEC within five days.

Dr. Nim Goldshtrom (23:00): That's not a trivial matter, we use this stuff all the time. The odds ratios in your analysis weren't forgiving, and yet the NEC percentages were so low, which makes you think there's some counterbalance between the human milk and the fortification. But it leads to one of the discussion points I'd love to hear from both of you on: what do we do for these

Dr. Kristin Elgersma (23:38): Yeah.

Dr. Nim Goldshtrom (23:55): extreme preemies, or let's just call it the single ventricle population, who have high calorie needs and can't always grow on unfortified human milk alone? Did this lead you to any conclusions about changing practice, or are we just going to have to live with this risk for now, as the cost of where the field is with fortification and human milk? Is there anything we can really do to balance growth and recovery against the risk of introducing non-human additives to nutrition?

Dr. Kristin Elgersma (24:20): That's a great, really hard question. I'm not sure we have very good tools for risk stratification yet, and that's one thing I think we could look at more closely. If you have a protocol, and your baby with single ventricle is at the post-op day where you'd typically start fortification, are there things we could look at more closely to say this particular baby is truly a good candidate for introducing a bovine-derived fortifier? Maybe yes, maybe no, but I don't think that's been looked at yet. That's probably where I'd start.

Dr. Nim Goldshtrom (24:55): And it's difficult because the numbers are getting smaller, we're collectively making improvements, especially in neonatology, and we can talk about human milk derived fortifiers too, although I think their impact on growth is still yet to be fully elucidated. But you had other positive findings too, human milk as

opposed to bovine-derived fortification potentially being impactful on NEC,

Dr. Kristin Elgersma (25:25): Mm.

Dr. Nim Goldshtrom (25:42): but there are a lot of other benefits, right, in terms of how much breast milk and breastfeeding impacted their overall health and their ability to leave the hospital in that period?

Dr. Kristin Elgersma (25:55): Yeah, that's a great point. One of our secondary outcomes was length of stay, and there we found substantial, fairly convincing findings, not wide confidence intervals, regarding the percentage of human milk during the neonatal period being associated with reduced length of stay. If you're a statistics buff like me, we did inverse probability weighting, a pretty rigorous method for causal inference, and found that going from 0% human milk to 100% human milk in the neonatal period alone was associated with about nine days shorter length of stay. I thought this was interesting too, because in lactation research you always have a risk of reverse causality, where the longer you stay, the harder it is to maintain a milk supply, so the less likely you are to continue with human milk. But we only looked at the neonatal period, which isn't a terribly long time to maintain a milk supply, and even so, it was still associated with an average of nine days shorter length of stay.

Dr. Nim Goldshtrom (26:55): That's incredible. Nine days is a very significant metric, forget cardiac ICU beds, just infants in a hospital in general. I'm surprised your hospital hasn't latched onto you and torn up the contracts with the formula companies at this point, given the advantage, seeing the impact of not just delivering human milk but using it broadly, physiologically,

Dr. Kristin Elgersma (27:21): Ha ha. Mm-hmm.

Dr. Nim Goldshtrom (27:36): it just makes things easier to deliver in a faster, better tolerated way, allowing families and babies to get through their recovery. When you control for so many other variables, it's really incredible. I don't know that we've seen those kinds of gains elsewhere in the neonatal world, most premature babies are going to get to their corrected gestational age plus a month or so before discharge, and I've never seen a study saying human milk versus fortified nutrition or formula is going to take a week off a baby's discharge date. It's usually feeding endurance, feeding skills, and whether your program does or doesn't send them home on an NG (nasogastric) tube. I'm curious why such a big gap. I can't find a good answer. Nine days is basically a whole other length of stay for some of these kids, like a coarctation repair. It's remarkable.

Dr. Kristin Elgersma (28:30): Yeah, I know. One thing I should mention, we did a subgroup analysis of just the single ventricle patients, and that difference was seventeen days. We thought maybe it would be different, maybe it's the healthiest kids driving this, but we didn't find that to necessarily be true. It's hard to explain. In my first study, my dissertation, I hypothesized that maybe this length of stay effect was driven by NEC reductions, but that doesn't really seem to be the case here. So I think it's an open question. With observational data, the true effect is probably not quite that large, but we accounted for as much as we really could, and I think there is an effect.

Dr. Nim Goldshtrom (29:15): If there was any more reason to promote human milk usage in congenital heart disease, you also had a very narrow window, this wasn't looked at over a ten year period where surgical practices would widely change, you looked at this over roughly a one to one and a half year period across all the centers, so even within those centers it's a very short time for significant practice change to happen.

Dr. Kristin Elgersma (29:40): Yes, two years.

Dr. Kristin Elgersma (29:47): And we had twenty five centers, so it's not being driven by any one practice, there's a lot of variability, whether you discharge a kid on a G-tube (gastrostomy tube) or an NG tube or not.

Dr. Nim Goldshtrom (30:00): I wonder if this is going to be one of the things that pushes programs and hospitals to say we've got to do better, wherever we are, in terms of supporting lactation and breastfeeding and how we set up our systems, because it's such a low cost way to do something physiologic. If we can get around the question of whether it's enough to support the child's growth and recovery to discharge, from a developmental standpoint it seems like a no brainer, but

Dr. Kristin Elgersma (30:20): Well.

Dr. Nim Goldshtrom (30:35): I think from your second aim, you found it's not that easy, and not every program has the same alignment of services, resources, and availability to do these things right now, which in 2026 I wouldn't have expected to be the landscape of lactation and breastfeeding support at major US children's hospitals.

Dr. Kristin Elgersma (30:56): Yeah, it's interesting. Personally, I wasn't that surprised. I think if you're more in the NICU world, there's much more of a general culture supporting lactation and breastfeeding there. It's definitely changed in the CICU since I started this work, I think it's really improving, but there was, as you mentioned, quite a bit

of variability. I can describe what the second aim was to introduce this. The second aim of the study was a survey of all the sites, to look at what lactation supportive practices they have. We developed this survey based on evidence from NICUs and well babies, in terms of what institutional things are supportive of breastfeeding and human milk.

Dr. Nim Goldshtrom (31:35): Yeah, please.

Dr. Kristin Elgersma (31:50): There were about 22 practices we asked about: things like, do you have hospital grade pumps, do you track your human milk and breastfeeding outcomes, do you have a skin-to-skin protocol. We also asked a CICU specific one, are there preoperative volume limits, which is something parents have said anecdotally really gets in the way of breastfeeding.

Dr. Nim Goldshtrom (32:10): Yeah, I'm part of that problem too.

Dr. Kristin Elgersma (32:20): So we looked at all these 22 practices across 34 sites, we had a few extra sites kind enough to complete the survey, and we found wide variation. The number of practices ranged from about 10 to 20 across the sites. Things like hospital grade pumps, every site offered that, 100%. Tracking human milk and breastfeeding outcomes was only 26%. I think that's interesting, because in the NICU you have Vermont Oxford Network tracking that as one of its outcomes, but in the CICU there isn't really any official measurement of this.

Dr. Nim Goldshtrom (32:55): Correct, the official measurement is whether you go home with a G-tube or not. That's an incredible landscape. It doesn't strike me as that surprising, in retrospect, since you're often surveying CICUs that may not know everything that's available in their own hospital's NICU, which again highlights that this is a large opportunity across multiple centers to get more involved.

Dr. Kristin Elgersma (33:17): Yes. Mm-hmm.

Dr. Nim Goldshtrom (33:28): And to go into these places with tons of evidence and data now, so much of what you're providing to the neonatal community, to say these babies need some of these practices, let us help you do the things we're already doing at the bedside for moms at most of our NICUs. It's refreshing to see the positive effect on a neonatal congenital heart population in the CICU, of breast milk and exposure to it, and again, the potential lingering problems that fortification and bovine milk exposure may have. But the potential gains from bringing this into a CICU, or, I'll speak a little heresy here, potentially bringing babies with heart disease into NICU environments for some period of time, because so much of the supportive infrastructure is already set up there. You'd have to do a lot of program building to make CICUs look like NICUs, and I don't know the right answer.

Dr. Kristin Elgersma (34:15): Mm-hmm.

Dr. Nim Goldshtrom (34:22): I'm obviously very biased about which direction I think things should go. But you're painting a picture where these babies should be thought of not just as congenital heart children, but as babies with a lot of neonatal needs, and a lot of system infrastructure that goes well beyond just stabilization before surgery and immediate postoperative recovery, infrastructure that's already built into a system, just in a completely different department. I don't know if you feel that at your center, or whether there's more of a bridge there compared to mine, where all our babies are already in the NICU, so we're doing basically everything you're describing to a large degree. Is that how your center operates, in terms of the units?

Dr. Kristin Elgersma (35:00): I have to give a big caveat, I don't practice clinically at all, I'm on the academic side, employed by the University of Minnesota. I work a lot with clinicians at our affiliated children's hospital, but I can't really speak to site practices because I'm not there myself. Our babies do start out in the NICU and then transfer to the CICU, it depends a bit on the diagnosis how quickly that transfer happens.

Dr. Nim Goldshtrom (35:25): Gotcha, that's

Dr. Kristin Elgersma (35:33): But I do know there are some areas of disconnect. For example, donor human milk is widely used in the NICU, and it can be used in the CICU too, but from what I understand you have to order it differently, it's not set up to be automatic.

Dr. Nim Goldshtrom (35:50): We have a lot of those limitations too, donor milk generally isn't available outside the NICU. Our cardiac babies are in what we call the cardiac infant unit, which is part of the NICU, so it's allowed there, but it's very hard to dispense from a system standpoint, how we store it, log it, and register it. I don't know if that's the case for you too, Adrianne, I don't know where else donor milk would be used at your hospital, but I can't imagine there are many places outside the NICU.

Dr. Adrianne Bischoff (36:20): That's a great question, I'm actually pretty ignorant about this. I don't know how it works in our pediatric ICU or cardiac ICU, I don't know the setup there. What I can tell you is that in general, babies are resuscitated by the NICU team, and have a brief initial period of stabilization in the NICU, where we're usually helping with placing umbilical lines, intubating, and sometimes confirming the diagnosis postnatally. But once it's confirmed, especially if it's a major or critical defect, the babies move on to the cardiac ICU pretty quickly, unless another diagnosis or issue keeps them with us in the NICU. Prematurity is one obvious example, or if they have other associated congenital anomalies the NICU is more used to managing, like an omphalocele or something major, then they'll stay with us.

We do have a growing practice of providing a neonatal consultation model within the CICU for some babies during that transition, so we can provide predominantly nutritional support and other things that might be slightly different in our practices.

Dr. Adrianne Bischoff (37:36): I wouldn't say it happens for every single baby, but our presence is being increasingly valued in the CICU world, to provide some of those perspectives.

Dr. Nim Goldshtrom (37:50): Music to my ears. Hopefully that'll gradually spread to other practices too, especially around the nutritional aspects and breastfeeding support that, Kristin, you've pointed out we do day to day in the NICU. If you had to pick the lowest hanging fruit you identified from this study, Kristin, what could programs do now, that aren't doing some of the high value things around promoting human milk or breastfeeding, to see these kinds of gains in

Dr. Kristin Elgersma (38:15): Yeah.

Dr. Nim Goldshtrom (38:17): patient protection, earlier discharge, and improvements in recovery?

Dr. Kristin Elgersma (38:25): One of the analyses we did looked at whether the number of practices a site has is associated with better lactation outcomes, and we didn't find that to be the case. But we did identify a couple of practices that, together, seemed to have some effect. Looking across all the outcomes, the two that stood out most were having a developmental care protocol in the unit, and having parent education, lactation materials, and or support groups. It seemed to matter whether those materials had some focus on hospitalized infants or on CHD specifically, and whether they were delivered prenatally as opposed to just postnatally. So I'd say the lowest hanging fruit is making sure you have some kind of educational material for parents that's institutionally approved, a consistent institutional message that results in some kind of formal support for parents

Dr. Nim Goldshtrom (39:15): available.

Dr. Nim Goldshtrom (39:33): That doesn't sound like a cumbersome thing for any program that doesn't have it developed yet to do. I can definitely speak to the fact that the more you can prenatally counsel a family on all the aspects, the high risk, the possibility of ECMO, reducing the surprise factor, the more it smooths out the delivery of care and the usual bumps in the road. So much can be challenging, as I'm sure you don't need me to describe, when postnatally you have to go through all of this for the first time and understand all these plans for how you're going to engage with your child, suddenly changing, and you're learning all this new information and having to figure it out. It can be overwhelming for families. It makes the most sense that the more you can lay out for families ahead of time, to get ahead of their thoughts, feelings, and planning, and give them a sense of control in an environment that can feel very out of their control, seems like a simple thing that can be done.

Dr. Kristin Elgersma (40:15): Yeah.

Dr. Nim Goldshtrom (40:25): One controversial question this raises, out of so many we could ask: human milk based fortification maybe isn't ideal, but we're now in a world where human milk derived fortifiers are available. From your literature review and your work in this area, do you think this is a potential middle ground, offering better growth without the potential risks of bovine exposure?

Dr. Kristin Elgersma (40:50): It's so interesting, I was actually just in a meeting before this talking about this very topic. I'm not sure, I feel like from the literature the jury is still a bit out, both in the NICU and the CICU, well, I should say mostly the NICU, since that's where most of the literature is, and you may have other opinions too, we could talk about that. What I think is still to be confirmed in the literature is that the base diet is almost never consistent between the groups being compared. So it's unclear to me whether any potential NEC benefits or growth benefits are the result of the fortifier itself, or a difference in the base diet, or both. That's where I still have questions.

Dr. Nim Goldshtrom (41:35): When you say base diet, can I ask, is that referring to the composition of mom's milk versus bovine formula, even at the same calorie count, is that the base difference you mean, or some other component?

Dr. Kristin Elgersma (42:06): Uh-huh.

Dr. Kristin Elgersma (42:18): That's an interesting question too, but what I meant is more that many of the studies look at infants who had an exclusive human milk diet, meaning exclusively mother's own milk supplemented by donor milk plus a human milk derived fortifier, while the other group doesn't necessarily have an exclusive mother's own milk diet, they can have formula. So is any difference the result of the fortifier, or the exposure to formula?

Dr. Nim Goldshtrom (42:45): I see, I see.

Dr. Kristin Elgersma (42:50): Correct, yeah. I think there are a few studies that have actually looked at that, holding it consistent, and those seem to show non-significant results.

Dr. Nim Goldshtrom (43:00): It's such a promising potential, but the results have to bear out in larger studies, and if they don't, that leaves us in a quandary about what to do. This might be controversial too, but do you think, or have you heard from clinicians, that this is changing their practice around not breastfeeding? I think that in itself should be something we're more accepting of, as a practice and a skill. If you're offering unfortified human milk, and babies are in a less critical state, the ability to offer them

Dr. Kristin Elgersma (43:27): Mm-hmm. Okay.

Dr. Nim Goldshtrom (43:27): We've seen kids held in their parents' arms on ECMO, we do very intense things. But in terms of using exclusive human milk diets versus trying to avoid fortification, have you heard feedback from colleagues about whether that's changing their practice based on your study's results?

Dr. Kristin Elgersma (43:46): I think yes, I've heard people are considering what they're doing a bit more. I don't know that it's been enough time for practice to change much yet, but I'd hope there are more questions being asked, like is this right for this patient, is this the right time for this patient. We have a couple of secondary analyses going on too, one of them looked at fortification trajectory,

Dr. Nim Goldshtrom (44:05): Sure, sure.

Dr. Kristin Elgersma (44:15): in terms of how fast the baby is fortified and subsequent NPO (nil per os, nothing by mouth) days, and it seems like perhaps a slower approach might be better in that way. So these are all important questions still to be answered, but I think there's maybe more awareness now that it's possible to do things differently, which is a good start.

Dr. Nim Goldshtrom (44:40): Yes, we've been changing, every five or ten years in the NICU, from adding donor milk to now human milk derived fortification. We're glad to see the rest of the cardiac ICU population helping us incorporate some of these things too. Where do you go from here next? Do you have more questions this is leading you to, future studies you're planning based on what you've learned?

Dr. Kristin Elgersma (45:00): Great question, I have about four studies going on. They're not all directly related to this, but I'm fortunate to be funded by a K12 award right now, and I'm looking at, it's a prospective clinical study, and one of my mentors is Sara Ramel, a neonatologist, my primary mentor is Michael Georgieff, also a neonatologist.

Dr. Nim Goldshtrom (45:20): So I guess that's a yes.

Dr. Kristin Elgersma (45:29): We're looking at body composition and growth quality, and their relationships to nutrition and neurodevelopment. That's sort of a focus. We do these kinds of broad epidemiological studies, like the one we just discussed, but I'm interested in drilling down further, seeing whether human milk composition plays a role, whether we can look at outcomes beyond the hospital stay, longer term neurodevelopmental outcomes. Are we measuring growth the right way? Are we just looking at weight gain? Weight gain is such a prominent topic in CHD, but in the NICU literature, Dr. Ramel and others have shown that length and fat-free mass may be more predictive of neurodevelopment. So that's something we're looking at.

Dr. Nim Goldshtrom (46:10): And length, head circumference.

Dr. Kristin Elgersma (46:27): Yep. So those are some things we're looking at. And we also have an exciting project looking at brain derived exosomes, so I have a bit of basic science going on too, with collaborators.

Dr. Nim Goldshtrom (46:40): That's incredible, this is just so refreshing to see, neonatology concepts brought to the CICU. I was hoping for bigger, stronger conclusions in terms of definitively protective effects, but you're right, part of the problem, consolidating all your research, is that I'd still be torn reading these papers and the manuscripts you have in submission now. It's really hard, we have to balance so many things, these kids have to grow, they won't leave the hospital, feed better, recover from wounds, or have their hearts repair if you can't get the right calories in. We're really stuck, it's not that human milk isn't great, but at some point it may not be enough on its own, just like with our micropreemies, who sometimes need six to twelve months of additives, more for micronutrients than for calorie requirements, to grow.

But we can't get away from it. I wonder if, as you pointed out, it's about how we're doing it, the timing and when to do it. You brought up the case of kids who, one or two feeds in, developed NEC. It's forever etched in my mind, early in my faculty career, a two month old I had in the NICU who'd been on human milk basically their whole life, about six weeks out from a coarctation repair,

Dr. Kristin Elgersma (48:13): No.

Dr. Nim Goldshtrom (48:32): was just a slow feeder, didn't do well, and in trying to get that kid to grow, we went up to twenty-two calories a day, and a day or two later, full blown, terrible NEC. These are individual cases, but as you were showing too, the incidence of NEC is thankfully coming down, but it's still terrible when it happens, and there's got to be something we can figure out. Your research is another

huge milestone in isolating some of the nuances that can give the next round of studies something to focus on, better timing, different intervals, a slower pace of fortification, letting the osmolarity adjust.

Dr. Kristin Elgersma (49:00): Yeah, and maybe human milk derived fortifiers are good in certain cases. That kid on twenty-two calories, that might have been a better option for that child.

Dr. Nim Goldshtrom (49:15): Who knows, maybe those unique cases self-select, in this precision medicine world we're getting into, where we're able to really hone in and find the kids at highest risk, and get them on some very specific combination of human milk, human milk fortifier, and maybe liquid protein, or other things we can make available in the outpatient setting. Difficult as it is, that's what that kid needs, because that child is uniquely at risk for whatever reason, and hopefully we get to that place in our careers, it would be a really rewarding thing to see.

Dr. Kristin Elgersma (49:45): I think it would be really helpful for families too, because it's just so stressful, that's the reason I got into this. It's very stressful for families, and anything we can do to make it a little better, with less feeding intolerance, less worry, I think would be great.

Dr. Nim Goldshtrom (49:50): If I could just get feeding and its toll on families out of the equation, that's really the second half of the job, for recovery: how do you help the family, the child, and the baby get over their endurance and eating challenges to get back to normal. It's a big struggle, but hopefully we have good, reasonable things to do, think about breastfeeding, think about using human milk as much as possible, given its clear benefits.

This has been great, Kristin. Thank you for taking the time to talk with us. Your research is remarkable, and we look forward to hearing more about it and your multiple upcoming studies, and to seeing this continue to change the landscape of how neonatal practices can help babies who aren't just in the NICU, but are still babies, along with the families who go through this with them.

Dr. Kristin Elgersma (50:30): Thank you so much for having me.

Dr. Adrianne Bischoff (50:35): Thanks for bringing this important topic to our listeners. I

think this was a very productive discussion, and thank you for being our guinea pig on this format, I anticipate people will really enjoy this. We appreciate you.

Dr. Nim Goldshtrom (50:44): Yeah.

Dr. Kristin Elgersma (50:51): Thanks.

Dr. Nim Goldshtrom (50:55): And again, for those listening, these are low hanging fruits, your CICU has tons of babies, and sometimes preemies too, depending, as you both, Adrianne and Kristin, so well pointed out, on how differently NICUs and CICUs operate around the country. Whether they realize it or not, they can value your input, these are ways you can cross that chasm and get more involved outside of your own unit, where babies still need your expertise and guidance. All right, thanks everyone for listening, I hope you enjoyed our first From the Expert panel of From the Heart. We look forward to having our next podcast with you as well. Take care.