Rob Steele, MD (Host): Welcome to Pediatrics in Practice, a CME podcast. I'm your host, Dr. Rob Steele, Executive Vice President and Chief Strategy and Innovation Officer at Children's Mercy Kansas City. Before we introduce our guest, I want to remind you to claim your CME credits after listening to today's episode, and you can do so by visiting cmkc.link/CMEpodcast, all one word, and Click Claim CME.

Today we are joined by Dr. Doug Blowey to talk about hypertension screening in the primary care setting. Dr. Blowey is a Pediatric Nephrologist and Associate Professor of Pediatrics at Children's Mercy Kansas City. In addition to his leadership roles as the Medical Director and Chief Integration Officer for the Integrated Care Solutions Program and the Medical Director of Children's Mercy Hospital Kansas; he remains clinically active in nephrology, serving as the Director of the Hypertension Program.

Dr. Blowey is a member of the American Academy of Pediatrics Subcommittee on Screening and Management of High Blood Pressure in Children, author of the 2017 Clinical Practice Guidelines for Screening and Management of High Blood Pressure in Children and Adolescents, and contributing author for the textbook, Pediatric Hypertension.

Dr. Blowey, thank you for joining us today.

Doug Blowey, MD: Thanks for inviting me, Rob. I appreciate it.

Host: Well, I'll tell you, with all the titles and all the great work that you're doing, you have to have a significant support system. I understand you are surrounded by women at home with your wife, three daughters, and I think you have a new granddaughter. Is that correct?

Doug Blowey, MD: Correct. All women. So taught me a lot of patience.

Host: That's right. Well, congratulations on all that. Let's jump right into it. Can you explain to our audience, exactly what is hypertension? And is there a difference between hypertension and just high blood pressure?

Doug Blowey, MD: So, when we think about blood pressure, we understand that the cardiovascular system's a closed system, the heart and blood vessels, and that as the heart beats, it pushes blood out and all the good stuff, right? All the oxygen and nutrients. So we need blood pressure in our system to function and to be healthy.

But when blood pressure is too high, it can be harmful to blood vessels, and over time can cause some health issues. So, that's why it's important to pay attention to blood pressure in everybody, including children.

Host: Very good. Well, so as the primary care pediatrician is seeing these children, typically we do our vital signs and all that, and that would include blood pressure. Can you give the listener a little bit of your thoughts on the importance of measuring blood pressure, and do you feel like that is something that should be measured at every opportunity? Is that something just for checkups? Is it something that should be measured with every ill visit too? Or, what advice you have?

Doug Blowey, MD: So, I think if we go back to what the primary focus of pediatrics is, it's preventative care, anticipatory guidance. Promotion of well being. And as we know that high blood pressure, is a problem that usually results in health issues as adults, it's a great example of pediatric care.

And the American Academy of Pediatrics recommends that you check blood pressure at annual well child visits from age three years on. The exception would be in those children that may have increased risk factors. Such as chronic disease, like kidney disease, some solid organ transplantation, heart disease, prematurity, that they have their blood pressure checked at annual or healthcare visits, before three years of age.

Host: Great. And when it comes to actually doing the measuring, I can remember back in residency, I mean, really going into depth about the right size pressure cuff and how to do that. Now, of course, there are devices that can help evaluate blood pressure that are just in the consumer market. Can you talk a little bit about the appropriate way to measure blood pressure? Are there other ways other than just the standard blood pressure cuff that would be acceptable just the way to measure that blood pressure?

Doug Blowey, MD: So I think most listeners will understand that blood pressure is a dynamic, vital sign. It changes a minute to minute. So, it's very important to have a standard operating procedure, standard procedure, to reduce technical related variations in blood pressure that may impact what you measure.

And for us, what's important is having repeated blood pressure measures over repeated visits that show a consistent pattern to help define what the blood pressure is. And as you mentioned, there's a lot of different ways to measure blood pressure. The two classical ways are the manual blood pressure, which is where you listen with a stethoscope to the Korotkoff sounds as you release the pressure that is placed on the arm. But more consistently now we use automated devices which are oscillometric ways to measure blood pressure. And those are pretty prevalent throughout things and manual blood pressure and the technique of manual blood pressure is really kind of being lost.

That's probably what's going on now is automated and the guidelines really kind of support using that primarily as your method of measuring blood pressure. Most times blood pressure is measured in the upper arms. And it's important to use, like I said, the standard procedure, making sure you have an appropriate sized cuff.

Too small of cuff will falsely elevate blood pressure. Too large of a cuff, probably not that big of a problem. So we like to avoid having too small of cuffs. Nowadays there are cuffs that go on your wrist. Those could be accurate, but there's not a lot of information, validation information about the accuracy of those in children.

They may be acceptable in children that have obesity and you can't get a cuff to fit on the upper arm very well. And then what's really not known is some of the other cuffless type systems, maybe some of the new technology; smart watches and things like that that may try to measure blood pressure.

It's really unclear how accurate those devices are, aren't recommended at this time.

Host: Great. That's really helpful. I know that sometimes it can be really confusing, particularly when, there's so many options on the market, not just, professionally for the pediatricians, but that, you have patients and families that are coming in that may have actually purchased some of those devices and giving them advice.

Doug Blowey, MD: Yeah, Rob, and one thing I might mention though is that it is a difficult thing for everybody to know what the right thing is. And because we know, we often ask parents to measure blood pressure at home or it's important or the pediatrician's office really aren't clear what do I tell them to get and stuff like that.

So we put together a great resource information, both for parents and for providers about, what type of devices have been validated, what type of devices might be appropriate, how to measure for the appropriate cuff size, and actually how to measure blood pressure at home. So if you go to childrensmercy.org, and you need to go to the nephrology clinic or hypertension clinic, there's a whole host of resources that will guide you to give them that information for parents and providers.

Host: That's fantastic and I really appreciate you bringing up the resource because I know that those are things that can be very helpful after the fact because you certainly can't memorize all of that information. So, thank you for doing that. Tell me, how do we treat high blood pressure? Actually, first of all, when is it concerning? At what point is high blood pressure really a concern for the primary care pediatrician if they've got a patient standing in front of them that seems to have a high blood pressure?

Doug Blowey, MD: What makes identifying high blood pressure in children so difficult is how we define what normal blood pressure is, is a little bit complex. So in the adult world, right, one size fits all. You get a number, you're too high or too low, and it's based on some outcome data.

Well, fortunately, kids don't have significant cardiovascular events in childhood, so it's hard for us to define high blood pressure based on outcome data. So, what we do is we have based normal blood pressure measures on statistical phenomena. So, you have your typical bell shaped curve, if you're to the right, or, you know, that 95 percent of people have a blood pressure lower than you, we would consider that your blood pressure is too high.

But what that creates for is that there's normal values based on age, gender, and height. So under the age of 13, there's a lot of looking up and defining what that blood pressure should be. So it's hard for providers to know what is normal. The most recent guidelines tried to simplify a little bit, and in that when you are over the age of 13, now, 13 and older, that the adult guidelines that are set as normal values. So, if you're less than 13, we're you still using the tables that are present in the guidelines. When you're 13 or over, we're using adult values, which is 130 over 80. So we are concerned when your blood pressure is repeatedly and consistently greater than either the 95th percentile or 130 over 80. And that defines that you probably have, what we would say, is hypertension.

Host: And I'm going to presume that that's not just a one time reading.

Doug Blowey, MD: Correct. It's repeated measures over repeated visits. And a lot of times, we'll see patients in clinic that have had a couple blood pressures that are elevated, you know, a single measure at a time. And a lot of times our first task is just to have the family do blood pressure monitoring at home, we usually ask them to do blood pressure three or four times a week for a couple of weeks, doing them in triplicate when they do it with using standard procedures.

We will occasionally use school nurses to perform that same task when parents aren't able or they don't have the access to an automated device at home. And then when we can't figure it out or it's just variable, we have a special monitor called an ambulatory blood pressure monitor. Essentially it's an automated device that we place on their arm and leave it on their arm for an entire day.

And throughout that day of normal activity, the blood pressure device automatically checks their blood pressure about every 20, 30 minutes. And, records it in a device that we can download later and view. So those are the way we try to define, you know, feel comfortable that what we're seeing is real.

Host: Great. And tell me as we look at the adult life of hypertension cause that's always in the news. You don't necessarily see that in pediatrics and there's an entity, that's, uh, I'll say at least understood, I don't know how much it's evidence based, of white coat hypertension with adults that, you know, their blood pressure goes up anytime they're around a doctor, which I can kind of understand that. Do you see that in pediatrics?

Doug Blowey, MD: Yes, we do. And it's felt to be much more prevalent in pediatrics. And, there's a lot of anxiety with kids. They're always scared to come to doctor's office. Think they're going to get shots, blood draws, and stuff like that. And then also we're seeing a lot of kids with anxiety disorders too, that really make it difficult to get blood pressure measurements.

So it's a very real thing. And that's why, again, doing blood pressure measurements outside the doctor's office is very useful. And again, the gold standard to defining white coat hypertension is our ambulatory blood pressure monitoring study. That usually defines somebody that has high office blood pressure measurements, but yet on the ABPM, their blood pressure pattern is normal.

Host: Wonderful. Well, good to know. I guess, we doctors, at least can recognize in our patients that, they may be nervous around us anyway. And that has implications, particularly when we're measuring blood pressure. What resources should we provide the families to address risk factors now related to high blood pressure? And I'm going to presume that those risk factors are going to be often prevalent throughout the family, not just necessarily the pediatric patient.

Doug Blowey, MD: You're exactly right. So, I think versus risk factors specifically for hypertension, I think more risk factors specifically for cardiovascular disease, which obviously is hugely prevalent. You know, a third of adults die from cardiovascular disease and hypertension is clearly the number one modifiable risk factor, but it also includes things like you mentioned.

So, cholesterol issues, elevated BMI or obesity issues, diabetes, lack of adequate physical activity, lack of adequate diet, tobacco use. So those are all things that we kind of think about and we kind of screen for when we see patients that are seen for elevated blood pressure measurements. And the risk factors specifically for hypertension we pay attention to, we try to think about why do you have high blood pressure and, what are the risk factors related to having high blood pressure?

And despite historically what the concern was that children probably were all due to some other underlying disease. The reality is that 90 percent of kids have essential hypertension. It means there's no specific problem going on. It's a combination of multiple factors, which include things such as you discussed, a family history, those are things you can't really modify who you're related to, being overweight, being physically activity, having a poor diet.

Those are all things that we're really looking for.

Host: Fantastic. Well, I imagine the conversations that you have with the families, those environmental factors that can be modified, they really are a family solution and likely would improve the health of the parents as part of that family unit as well.

Doug Blowey, MD: You are exactly right. We do counseling for the children and it's hard to ask them to do things that, you know, aren't happening in the family. And so when we can get the buy-in from the family, a lot of times, that is useful. And going back to how do we deal with it?

When I try to get the child and the families to understand why blood pressure is a risk factor for their life; and it's important to pay attention to it now. Because now is when things are starting. It just takes a long time for the pathophysiology to play out.

As I mentioned, we have that childrensmercy.orgHypertensionClinic, resource page. And within that, there's a lot of information for families that we provide in clinic. We really stress a healthy eating plan that's low in sodium. There's a well known thing called DASH diet, Dietary Approaches to Stopping Hypertension.

And there's information on there, and there's even a video, both in English and Spanish, that our nutritionists put together that is excellent, really helps patients understand what it is, how to do it, how to read labels and things like that. We also put some information in there about increasing physical activity and how do you do it.

 I can't remember what the American Academy of Pediatrics site is, Healthy Steps or something like that, that we link to that to give them information on that. So there are resources that we try to provide consistently to both patients and helping their families also will take it in mind.

Host: Very good. Dr. Doug Blowey, thank you so much for joining us on this CME podcast. You know, speaking of families and family units, and we've talked about yours, you are fortunate to be surrounded by women, but I have a question. You have a set of twins, your girls are twins. I have a set of twin boys, mine are 16 at this point. And so my key question for you is when your girls were younger, particularly your twins, did they use their twin powers for good or for evil? I can tell you my boys often used it for evil.

Doug Blowey, MD: They're girls, so I'm going to say for good.

Host: Okay. I would kind of expect that. Dr. Blowey, thank you so much for joining us today. As a reminder, claim your CME credit for listening to our show today, visit cmkc.link/CMEpodcast and click the claim CME button. This has been another episode of Pediatrics in Practice, a CME podcast.

See you next time.