NICHD-funded study explores the toll of pediatric trauma


newborn in hospitalMeredith Carlson Daly: Welcome to Milestones, a podcast featuring research and insights into child health and human development.

I am your host, Meredith Carlson Daly.

Today we talk with Dr. Sheri Crow, a pediatrician specializing in critical care at the Mayo Clinic in Minnesota. She is the lead author of a recent NICHD-funded study that looks at the long-term health outcomes of children who experience a traumatic injury or life-threatening illness in their youth.

Crow and her colleagues compiled health and medical records, as well as school performance data, for more than 9,000 children born between 2003 and 2007 in a small metropolitan county. They tracked admissions to the pediatric intensive care unit, or ICU, the causes of these admissions, the length of the stay, and the types of treatment during this 5-year period. They continued to track ICU admission rates for this group up to the end of 2013.

The study found that ICU admission rates were highest in the first year of life and then declined steadily. Respiratory problems were among the most common causes of admissions at any age, while more than 66 percent of children admitted after 1 year of age had a chronic, pre-existing health condition.

According to Dr. Crow, the study is the first to chronicle critical illness within a population-based birth group of U.S. children. The results demonstrate the changing incidence, presentation, and healthcare requirements of critical illness as children age.

Dr. Crow, thank you for joining us.

Dr. Crow: Thank you for having me.

Ms. Daly: So, Dr. Crow, can you tell us what prompted you to conduct this study? 

Dr. Crow: Well, I love being asked this question because I think it gives an opportunity to sort of relate to everyone what it is that we do as pediatric intensivists, and fortunately, that’s not a specialty that a lot of people have heard of because, as you can see from our study, getting critically ill enough to end up in the intensive care unit is fortunately still a rare event for most children.

However, as a pediatric intensivist, what we do is we take care of any kid, whether they are starting out healthy or have underlying health problems, and if they become sick enough that they require admission to a pediatric intensive care unit, we are the physicians that continue to care for them and try to bring them through to a better state of health.

These children will represent a wide spectrum of childhood illness, trauma and surgical interventions, and although we see all types of different diagnoses for each child, we are learning that there are many characteristics of the ICU experience that will pose similar threats to the patient’s and family’s long term well-being.

Any parents listening to this right now won’t have to try very hard to understand why being admitted to an intensive care unit as a child might be considered a traumatic experience.

If you’ll just stop with me for a minute and imagine that you’re home from work in the afternoon, your child is out riding their bike just a block or two away from you and unfortunately, a car pulls out and they’re hit.

An ambulance is called by the bystanders. They’re loaded into the ambulance. They’re resuscitated by the crew. They’re brought into the nearest emergency department, all while the police are trying to find you, their parent or whoever is the guardian, to notify that your child has been taken to a hospital and has been injured.

Somewhere during that process, as the parent, if you have other children or other things that you need to quickly take care of so that you can drive yourself to the hospital, you can begin to imagine the stress that mounts as you really don’t have any details and are unsure about just how badly your child is injured.

Meanwhile, at that hospital, the ambulance arrives with your child. They have been without their guardian or parent through this whole process. And in the emergency room bay, the doctors and nurses work quickly to try to stabilize that child and bring them to health and keep them healthy.

And they’re very good at what they do but it requires x-rays and lab studies which includes blood draws and probably IV placement. So, you have all of these strangers suddenly descending on your child without their guardian there to keep a watchful eye.

At some point, you’re reunited. They’re transitioned up to the Intensive Care Unit so that they can continue to recover. And for many of these kids, they may expect a full recovery and as the health-care team, we likely expect them to go back to their normal state of being and doing the normal things that normal kid do after this ICU event.

Unfortunately, you, the parent, can imagine all the different emotions and things that would go along with this that might stay with you for a long time yet to come. Even if it wasn’t a traumatic event, let’s say you brought your child in with pneumonia or an asthma exacerbation, we’re still bringing in strangers into this child’s life and doing things that are both scary in the setting where a parent doesn’t yet know what the outcome for their child will be.

Take it the next step that once you get into the ICU, in the best-case scenario, you’ve got a health-care team that’s supportive of you. They build a sense of trust and security. There’re all sorts of wonderful, multi-disciplinary caregivers that help reassure you that your child will not only recover, but hopefully have a bright future so they continue to improve. You’re discharged. That seems like such a celebratory event and yet, now you’ve returned home with that entire support system just suddenly back at the hospital and you’re left to face whatever the residual effects are in your home. 

We have growing concerns that all of this experience will change your perception of your child’s resilience - the potential that you think that they have. You may feel isolated because of all the different emotions that you felt during this experience and yet your child may now seem just like every other child out there. And add to this effect, that even your primary care provider, who you’ll continue to go to for support, may not have all the emotional or difficult details of this process.

So, from a scientific standpoint, we’re learning more and more that these events, whether they’re trauma related or medically related - meet all the criteria for what we would call a ‘traumatic event.’ And the trauma research community has done an excellent job of outlining that there can be a lot of psychological implications and even physical implications for patients who appear to have recovered, but still deal with the sort of posttraumatic stress of this incident.

So, I think for me, watching all of this and being a parent myself, I just really started feeling like myself and then what I saw coming out a little bit in the research, was that there’re probably things that we can do during this process to potentially reframe the parent and family experience, so that they leave with both a plan, a follow-up to help deal with issues that are going to arise, and just a better support system to deal with any long-term challenges.

Ms. Daly:  It used to be that just surviving a pediatric intensive care unit admission was the goal. Today, the survival rate is an impressive 97% among pediatric ICU patients. So, now the focus turns to what happens after these patients leave the ICU. Can you explain how you will monitor their progress for us?

Dr. Crow: Definitely. We have kind of a unique opportunity here in Olmsted County, Minnesota. Back in 1904, the Mayo Clinic started something called the Rochester Epidemiology Project. And what that’s done is it’s actually linked the medical records of all of the county inhabitants over time, so for anyone living here in this county, they have - any healthcare system that they access within this community, those visits are all linked within a record so that we can actually follow every single medical encounter across their lifespan. That actually even starts with their birth certificates, at birth, and if - because you’re able to look at the parent and family records, as well, we can even look back at their prenatal history prior to birth.

The other component that an investigator here at the Mayo clinic, named Becca Katusik, was able to develop in the last 20 years, is to provide access to the school records of the same community. They’ve worked out a very special agreement with the school district here and we’re now able to access the school records for children within this community so that we can look at their academic outcomes as they grow and age through the system.

One final thing that is very helpful, is that it’s a requirement in Minnesota that before you enter kindergarten, you have to go through an early childhood screening process where we look at things like speech development and just your overall developmental progress between age three and five. And all of those testing procedures are available within the documents as well. Now, it’s very important to highlight that patient privacy is really important for a research opportunity like this.

And the Rochester Epidemiology Project is very careful to clear all studies through the internal review board of the medical systems within the community and then patients are also given the opportunity to opt out of this study if they decide they don’t want their medical records used for research.

But to date, we have about a 96% participation rate for the population and that gives us a lot of rich data to evaluate the effects of things like critical illness within this population cohort.

Ms. Daly: Well a 96% response rate is truly amazing. So, what’s next?

Dr. Crow: Well, I think the next thing that is really important to do is what I referred to earlier, where we need to find out what are the long-term implications of critical illness or this traumatic event for these families. And the challenge of all of us in the peds ICU is that we - our patients by definition, are usually referred in from a large area. They come to us only when their sickness exceeds the level of care at their local hospital.

And as a result, that means that when they’re discharged from the ICU, they go back home to their local community and it can be incredibly difficult and expensive to try to bring them back to us so that we can understand what’s happening to them over the long-term.

And there have been many wonderful studies that have looked at smaller populations trying to track those patients over time, mostly for specific disease entities, but all of these are challenged by loss of follow-up as patients move around and just become lost to the investigators. So, the beauty of having this geographically defined population that tends to have a lower migration rate to start with, is that we can look at these medical records and these school records that accumulate as part of their life. This is just real life, every day, living in this community. The results of medical encounters and their performance at school all get logged into this data resource. And we can actually look at things, both within our patients and within their families to see how they’re functioning in the real world.

For example, I can look to see how many missed days of school or what’s the graduation rate for this cohort in this paper. They’re 11 and 12 years now but in, you know, a few years, they’ll be reaching graduation ages and we can actually look and see what their employment rate is afterwards. We can look at things like mental health diagnoses in the parents and families to see if that rate of healthcare utilization goes up or down after they experience these ICU events.

And I think one of the things that’s perhaps most interesting is to find out even what happens financially for these families. Does an admission to the intensive care unit impacts your long-term socioeconomic trajectory? Anyone that’s ever gotten a medical bill for even a minor intervention for their child knows that this can be sort of a deal breaker for a lot of families. So, I think that long-term follow-up, using the accumulation of medical records, will be the first step. And then the second step will actually be to get permission to contact these children within the cohort and follow them prospectively and do more face-to-face interactions since they do live right here in the community as we speak.

Ms. Daly: What can the data tell us?

Dr. Crow: Well, I’ve done a little bit of preliminary work with some of our local families that tend to be recurrent admissions to the Intensive Care Unit. And I think what we’re going to find is similar to what some of the other researchers in the field are finding, that it’s not as important what the diagnosis is or perhaps even the details of the clinical course.

That what may be most important is the parental, family, patient perception about how threatening to life this experience was. And I think we’ll - I hope that we’ll be able to identify different characteristics of family structure or the local environment and even the ICU experience itself that promotes resiliency or that placed patients at risk so that we can actually target families that meet that sort of profile for being vulnerable.

You know, I think the hardest thing about our healthcare system right now is that there aren’t unlimited resources. You know, we’re very fortunate to live here in America, but we still have families that would benefit from more social work involvement or perhaps a home-health visit.

But right now, we don’t have any way to really differentiate those families and identify where these limited resources would be best utilized. So, I think if I can start by finding out those high-risk families and patients and then targeting the resources that are available towards their follow-up and outcome, it might even be as simple as more financial counseling, for example, during their ICU stay.

I think we’re going to find that there’re some fairly straightforward things that we can make a significant difference in just by prepping and advising our families differently.

Ms. Daly: I’m still having a hard time understanding how an experience in the intensive care unit can later lead to physical or cognitive problems down the road. Can you elaborate?

Dr. Crow: Definitely, I - you know, I think that’s actually one of the most important questions that we hope to discover through this study. We know that psychological well-being is very important for the development of a child. We also know that the family’s psychological well-being actually directly interacts with a child’s developmental trajectory. However, it’s likely that there are even more aspects of the clinical course while the child is in the Intensive Care Unit at an early age, that may have implications for their long-term neuro-developmental functions.
So, let’s say that your child comes in with pneumonia and we end up having to put them on a ventilator and their oxygen levels are intermittently low. Right now, we think that those kids should still do okay and not have too many issues, but we don’t really know because we don’t get to follow them ten years after they get off of the ventilator and go home and go back to their normal lives.

Other examples are there is new evidence that is coming out, some from my mentor, David Warner, where they’re looking at frequent anesthesia exposure and how that might impact school outcomes later on in life. There is similar evidence to suggest that the sedative drugs that we use during an ICU stay to keep a child comfortable, to reduce the trauma of all the scary things that are going on around them, those drugs themselves may have implications for how the brain continues to develop after they leave the Intensive Care Unit or promote injury sort of during the process of critical illness.

There’s a myriad of other possibilities of how a child who’s in a life-threatening situation, which they are because they’re requiring the ICU, there is a lot of possibilities for how both the illness and the interventions we do to take care for the illness may impact brain development.
And we would expect, then, if that’s the case, to find out that when we look at these kids at school age, and this is data that I’m working on right now, we would find higher rates of learning difficulties or speech development, outward evidence that the brain has undergone some delay or change in the expected trajectory of development based on this critical illness event.

Ms. Daly: Is there anything else you would like to mention that we haven’t discussed?

Dr. Crow: I think I would just like to state again that, really, what we need to know is what happens to these patients and their families over time, what’s the toll that it takes after they’ve gone through an Intensive Care Unit admission?

For me, a mother, a researcher, a pediatrician, that’s what make this work exciting. To understand how families are functioning in the real world, it would help us document their experiences, inform medical professionals and the families down the road what they can expect, how to better prepare for the stress that’s anticipated, and ultimately to improve their quality of life.

Ms. Daly: Dr. Crow, thank you so much for your time today.

I’ve been speaking with Dr. Sheri Crow, a pediatric critical care specialist at the Mayo Clinic.

I'm your host, Meredith Carlson Daly. Thank you for listening to Milestones.

Crow, Sheri S. MD, MS et al. Epidemiology of Pediatric Critical Illness in a Population-Based Birth Cohort in Olmsted County, MN. Pediatric Critical Care Medicine; March 2017


About the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD): The NICHD sponsors research on development, before and after birth; maternal, child, and family health; reproductive biology and population issues; and medical rehabilitation. For more information, visit the Institute's website at

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