NEONATAL STROKE
Stroke has been increasingly recognized in children in
recent years. Neonatal stroke in particular occurs at a much higher rate than
in older children. What are the risk factors of neonatal stroke, how is it
diagnosed, and what are the recommendations for managing stroke in newborns.
You are listening to ReachMD XM 157, the channel for
medical professionals. Welcome to the clinicians roundtable. I am your host,
Dr. Jennifer Shu, practicing general pediatrician and author. My guest is Dr.
E. Steve Roach, Professor of Pediatrics and Neurology at the Ohio State
University College of Medicine and Chief of Neurology at Nationwide Children's
Hospital in Columbus, Ohio.
DR. JENNIFER SHU:
Welcome Dr. Roach. Dr. Roach you are the lead author of a
New American Heart Association scientific statement on managing stroke in
infants and children. What was the impetus for publishing this statement now?
DR. E. STEVE ROACH
In recent years we have come to realize that this is a major
problem and we have gotten away from this idea that stroke just simply does not
occur in children and the reason for doing this paper at this point is that we
believe that there is a considerable gap between those obviously who study the
topic in detail and know the topic and those people who are out there on a
day-to-day basis who are then faced with having to take care of these
children. So, the impetus for the paper is to try to narrow that gap so that
we can put everything down in one place by a group of people who reach a
consensus on how to diagnose, how to manage these children, and make it
available to anyone who needs it.
DR. JENNIFER SHU:
In your paper you mentioned that a large proportion of
stroke in children actually occurred in newborns. How do you define newborn or
neonatal or perinatal stroke?
DR. E. STEVE ROACH
You see it is defined differently in different places, but
we basically define neonatal the same as everyone else and this concept of
perinatal stroke comes from the recognition that some of these strokes actually
occur prior birth and the need therefore to expand our horizon just a little
bit. We have good evidence that some strokes occur before birth and in fact
some of the children who are born a bit early the stroke may be the cause for
precipitating the early delivery as opposed to say the delivery itself causing
the stroke.
DR. JENNIFER SHU:
Now for the neonatal stroke, would your definition then be
in the first 28 days of life or 7 days, how is that defined?
DR. E. STEVE ROACH
I tell you it is 28. We argued that point, but I think it
is 28 that is what we settled down on the paper.
DR. JENNIFER SHU:
Now, let's talk a little bit more about neonatal stroke, how
common is it?
DR. E. STEVE ROACH
It is much, much more common than we once would have
thought. Current evidence suggests that it occurs about once in 4000 live
births.
DR. JENNIFER SHU:
And would you say that most of those would be of ischemic
type or hemorrhagic.
DR. E. STEVE ROACH
Mostly ischemic.
DR. JENNIFER SHU:
All right.
What kind of risk factors might you see in a neonatal
stroke?
DR. E. STEVE ROACH
A lot of the children have no identifiable risk factors, and
of those who do, there is evidence now that children and their mother's who
have some intrinsic coagulopathy have an increased risk of stroke. There is
evidence that inflammation of the placenta increases the risk of stroke. Congenital
heart disease of course we have long recognized this as a risk of stroke and
that is certainly true also in neonates, so those are the main things –
coagulopathy, amnionitis, congenital heart disease, and when you start seeing
those things in combination, the risk of stroke goes up even further, but a lot
of the children still have no identifiable risk.
DR. JENNIFER SHU:
Now what if there is some birth trauma without any
coagulopathy, is that a risk factor?
DR. E. STEVE ROACH
Almost certainly overrated. Most of these children have no
difference in their risk factors, normal or traumatic birth than anyone else
and it is true, however, that sometimes the stroke gets blamed on the delivery,
but there is actually relatively little evidence for that in most children. I
am sure there are exceptions, but most of these kids are born just like
everyone else and are recognized a few hours after birth when they start having
a seizure, but they really do not have a consistent history of birth trauma.
DR. JENNIFER SHU:
Are there any medications that the mother might get or the
newborn might get or any drugs of abuse that might increase the risk of
neonatal stroke?
DR. E. STEVE ROACH
Probably, there is not great empiric evidence as to how
often that happens, but certainly there are case reports of children having
stroke after their mothers took cocaine or other stimulants. There are reports
of babies having hemorrhagic tendency in response to mothers taking certain
anticonvulsant drugs such as phenytoin or phenobarbital and of course we have
been talking about ischemic stroke and of course major hemorrhagic tendency
would predispose to hemorrhagic stroke, but certainly there is precedent for
drugs taken by mother causing a stroke in babies.
DR. JENNIFER SHU:
You mentioned that seizures in the first few hours of life
might be one presentation, is that the most common presentation?
DR. E. STEVE ROACH
It is. Absolutely.
DR. JENNIFER SHU:
Other ways that a stroke might present in the newborn
period.
DR. E. STEVE ROACH
Sure. Occasionally you will see babies who are just
lethargic and not as responsive as usual ,do not want to feed as well as usual
and that prompts some kind of evaluation and we find the stroke that way.
Sometimes we find a stroke actually later even though we think it occurred in
the neonatal period. The typical scenario there is a family who bring in a 6-
to 8-month-old child and they have noticed that the right arm is not used as
much or as consistently or as well as the left arm or something of that sort or
that child is slow to develop or whatever and then occasionally even later
still as a 3, 4, or 5-year-old child they will come in with epileptic seizures
and the evaluation for the seizures will find what is clearly an old prior stroke
that when we added all up we conclude this probably occurred during the
neonatal period, but I would think the majority of the kids will show up with
seizures in the neonatal period.
If you have just joined us, you are listening to the clinicians'
roundtable on ReachMD XM 157. I am your host, Dr. Jennifer Shu. Our guest is
Dr. E. Steve Roach, Professor of Pediatrics and Neurology at the Ohio State
University College of Medicine and Chief of Neurology at Nationwide Children's
Hospital in Columbus, Ohio. We are discussing neonatal stroke.
DR. JENNIFER SHU:
Let's talk a little bit about the diagnosis in neonatal
stroke. How do you look for it, to diagnose it?
DR. E. STEVE ROACH
In terms of confirming with a test given that you are
dealing with neonates, probably the first thing that is done in most nurseries
would be a cranial ultrasound and you can identify the lesion, but often times
it is not as clear as to the nature of the lesion as it will be if you do a CT
scan or MRI scan, but the first step of course is suspecting the diagnosis, but
then in terms of confirming the diagnosis, usually the first test is an
ultrasound and then almost always you have to follow that up then with a CT or
a MRI scan.
DR. JENNIFER SHU:
Are there any places where an MRA or MRV with CT angiogram
might be useful?
DR. E. STEVE ROACH
We have not got a lot of experience yet in babies with CT
angiograms and of course then one increasing concern is trying to limit the
amount of radiation. We do with some regularity to MRA/MRV in these children
and we did not talk about venous thrombosis, but certainly babies have an
increased risk of that as well. So, some of those babies will present with
seizures, some of them with different things, but we do MRVs in babies with
some regularity, but in terms of just the standard ischemic stroke typically
not an MRV, sometimes an MRA though.
DR. JENNIFER SHU:
Now this is such a tight time here in the immediate
perinatal period and then plus 28 days of life, is it possible to tell the age
of the stroke on ultrasound or CT or MRI.
DR. E. STEVE ROACH
Not ultrasound to my knowledge. CT occasionally if you add
the CT contrast sometimes you will see contrast enhancement of the stroke and
we have recognized that that phenomenon does not usually occur for a couple of
days, so for example if you have a newborn who begins having seizures at 8
hours of life and you do the CT then you already have contrast enhancement of
the abnormality, you can assume that stroke is considerably older than 8 hours
and probably couple of days, and given that hypothetical scenario, what that
means is that stroke occurred before the delivery. Similarly, there are some
MRI parameters that someone who deals with MRI all the time can often give you
at least an estimate about how old the stroke is, but not usually with
ultrasound.
DR. JENNIFER SHU:
When you are saying stroke in such a young age, what is the
prognosis, the outcome, any residual effects. Is it better to get stroke as an
infant or is it better to get stroke later on in life?
DR. E. STEVE ROACH
If you are going to assume the same size of abnormality and
so on, it is arguably better to get it early than later because there is enough
plasticity of the brain that to some extent anyway you can actually learn test
that would have been done by that part of the brain with other parts of the
brain. The biggest example of that probably is language. A baby who has a
stroke in what would eventually become the language area typically will learn
to talk, now their vocabulary may not be as rich as it would have been or they
may have word finding difficulties or whatever, but almost always they learn to
talk whereas the same abnormality in a 10- or 15-year-old or of course in an
adult, you might or might not then regain language function once you developed
it so. There is a limit to the plasticity notion, though it is the old idea
that if you are a baby you have almost unlimited potential to recover from a
stroke or other injury. This simply is true. I mean if you have a large
lesion or multiple abnormalities, there is going to be a price to pay for that,
so what if you are talking about a small abnormality, the chances of a good
functional recovery is pretty good whether you are talking about a neonate or
an older child, but it is probably better in the neonate.
DR. JENNIFER SHU:
Would you expect any recurrence of the stroke to happen or
chronic seizure disorder anything like that?
DR. E. STEVE ROACH
Most of the babies do not have another stroke. It depends a
bit on why they have the stroke to begin with and certainly if they have
congenital heart disease that has not been fixed that would represent an
ongoing stroke risk for additional strokes. The average typical neonate with
the stroke who probably had it for reasons that we cannot identify almost never
do have a second stroke in those kids. In that sense, the prognosis is
excellent. The second part of your question about seizures, while most of these
kids present because they had a seizure in the neonatal period or even in the
nursery, it is relatively unusual for that to persist as epilepsy. I think the
current estimate of the neonates who have a stroke probably about 15% of them
eventually will develop chronic epilepsy, most of the time the seizures are
just in response to the acute injury and those seizures almost always go away,
but then about 15% of the time, those children will resume having seizures
later.
DR. JENNIFER SHU:
Let's talk a little bit about the management of acute
stroke. Obviously, there is supportive care such as oxygen and fluids, but
what about any type of thrombolytic or other pharmacologic therapy, is that
indicated in newborns?
DR. E. STEVE ROACH
Well the problem is we have no data. Certainly, the
thrombolytic agents are not approved in the United States for children of any
age let alone neonates and we basically in this paper wrestled with that issue
a great deal and decided that the appropriate place to use thrombolytic agents
in a child or particularly in a neonate was in the setting of a clinical
trial. We are recommending that they not be used in neonates except in a very
controlled setting like that. We do not know if the risk is the same. Part of
the problem of course is how do you ascertain when the stroke occurred. Even
in adults, the usual recommendation is do not use a thrombolytic for an
ischemic stroke after about 3 hours because the rate of hemorrhage goes way
up. Well, if we are dealing with a 10-hour-old baby whose stroke might have
occurred even before they are born, obviously we have a problem and that is
aside from just the fact that you know there are so few times it has actually
been used. So, we are discouraging thrombolytics, although it would be
appropriate to do more research on it.
DR. JENNIFER SHU:
I would like to thank our guest, Dr. E. Steve Roach. We
have been discussing neonatal stroke. I am Dr. Jennifer Shu.
You have been listening to the clinicians' roundtable on
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