The Practicing Parent: Newborn Heart Test
Mon, 07 Oct 2013 22:45:53 GMT —
30% of infant deaths in the U.S. are because of congenital heart defects. There's a new test for newborns which can help detect deadly heart
problems, it's called Pulse-Oximetry.
A light source and sensor measure the blood oxygen levels of the newborn. A healthy saturation is 96% or greater.
Cohen Children's Medical Director Dr. Robert Koppel says it gives parents peace of mind. "Although we can't be absolutely certain that the baby doesn't have an
underlying potentially lethal problem, we know that that's far less likely than it was a generation ago," Koppel said.
There is some fear it can also lead to false positive results that are costly and stressful for the family, but a study out of Britain showed a false positive
rate of 1 in 3,000 cases.
Dr. Koppel believes early detection outweighs any negatives. "Treatment is so effective at saving lives," he said.
Studies show 1 in 6 babies who die from critical congenital heart disease are underdiagnosed and unrecognized cases. An estimated 1,200 babies a
year could be diagnosed sooner and infant deaths could be prevented if the Pulse Oximetry was routinely used.
For hospitals that do have the Pulse Oximetry machine, the only additional cost is for use of the probe, which is about one dollar per reusable probe or
$7-$8 for a single-use probe.
A pulse oximetry screening is now being performed on newborns
across the U.S. with the exception of a few states. Newborns are tested for
heart defects in hospitals just moments after birth to detect any potential or
current heart complications. Before performing the screening, doctors place a
probe on the infant's foot then they begin the screening. The blood oxygen
level is measured by light source and sensors which determine how healthy the
heart is. The test screens for the seven most vital heart diseases to save the
lives of newborns and prevent further complications. This procedure provides
comfort and relief to parents as they feel that their child is in good health.
Depending on the severity of the disease, a child may or may not
need to be treated. If treatment is needed, then a catheter or surgery can
repair the irregularity. If the disease cannot be treated with the use of a
catheter, then doctors perform open-heart surgery to fix the defect.
Robert Koppel, MD, Medical Director, Regional Perinatal Center, Cohen
Children's Medical Center of New York, and Associate Professor of Pediatrics,
Hofstra North Shore - LIJ School of Medicine, talks about the test:
What is pulse oximetry?
Dr. Koppel: Pulse oximetry is a technology that's been around for quite a long
time, it was developed in the 1970s. It's a noninvasive way of measuring the
oxygen saturation of a patient's blood. And it relies on transmitting a
specific wave length of red light through an extremity, such as a hand or foot
or a fingertip. The device is able to interpret the amount of light that passes
through the extremity and convert that in to a percentage of red blood cells
that are carrying oxygen. It displays a number that's called oxygen saturation.
Why is it needed?
Dr. Koppel: Well it's very useful for all patients in terms of a vital sign
that gives us an assessment of the oxygen status of the patient. And what we've
known for some time now is that it can also be useful as a screening test to
detect subtle degrees of decreased oxygen in babies who may have critical
congenital heart disease. These are babies that may look pink to us when we
just look at them using our eyes but in fact our eyes can deceive us. Although
the babies look pink to us their oxygen levels may be slightly low and that
might be an indication that they have a critical congenital heart defect.
How easy is the procedure?
Dr. Koppel: It's very simple. It's a procedure that's done on patients in the
hospital very routinely, and is completely painless, and noninvasive. It simply
involves placing a probe that has a red light on one side and a sensor on the
other, and a cable that attaches to a device. And it gives us a display that
tells us the patient's heart rate with the oxygen saturation, and it all can be
done in less than a minute.
How long have you been doing this here?
Dr. Koppel: We were very early adopters of pulse oximetry screening. The
initial reports came out in the spring of 1995 and by 1998 we undertook a
clinical trial here at Long Island Jewish Medical Center. So we've been doing
this for fifteen years. We've published our data and it's been incorporated
into the collection of world literature that has now reached a point where
governments, ministries of health, and departments of health have been able to
endorse the use of pulse oximetry as a screen for critical congenital heart
disease. It's really very quick; it takes only about a minute to get a reading,
but we measure in two locations. We measure in the right hand as well as one
of the feet. So the estimate is that the screen itself takes about five minutes
from start to finish. It is completely painless; it's nothing more than
wrapping something that looks like a band aide around the hand or the foot.
Are all of them the same? I thought one only used the foot.
Dr. Koppel: The nature of the test is that it can be done in one extremity, in
which case it should be the foot but the current national recommendation is to
do the right hand as well. The feeling is that by doing the right hand
together with one of the feet you can increase your detection of one of the
more common of the critical heart defects called coarctation of the aorta. The
problem is that you might increase your risk of having a false positive result
by doing two measurements. But on balance, the feeling is that if you can
increase the sensitivity of the test to find the most common defect then it's
worth the risk of having a few more false positives cases.
What can be found and can these conditions be deadly?
Dr. Koppel: The nature of congenital heart disease is that it's quite common;
there are about one in 100 babies that have some type of heart defect.
Thankfully, three-quarters of them are not considered critical. They might
cause problems after a few weeks or months but they're not likely to be lethal.
However, one in four babies with a heart defect has what's called critical
congenital heart disease. That's defined as a heart defect that requires some
type of intervention during the first year of life. So the problems that we're
screening for with the pulse oximetry are for that category, the critical
congenital heart disease. Most of those babies can be picked up with pulse
oximetry because these are conditions that result in a decreased oxygen level.
But there are some that may not and for that reason pulse oximetry screening
was never intended to replace the physical examination. Pediatric caregivers
are still expected to perform a detailed physical examination and discharge
instructions to families should include instructions on signs to watch out for.
The signs to watch out for might be blue discoloration or difficulty feeding,
rapid breathing, etc.
So mom, or mom and dad come in; tell me how the process works, when do you guys
tell them about it? And when does this baby get tested?
Dr. Koppel: Well, this is part of our routine newborn screening process. Which
New York State has been a leader in since the very beginning when newborn
screening first started in the 1960s. Most newborn screening is traditionally
based on the collection of dried blood spots from a heel stick. And the blood
is sent off to a lab in the state's public health lab where screening is done
for over 45 different disorders. But more recently, newborn screening has
expanded to include physiologic testing for conditions such as hearing loss.
And now pulse oximetry screening is added to that list of other conditions for
which we screen babies. So the way we do it here at our hospital, is we wait
until the babies are at the time point where they need to have their blood
spots collected for the state screening. At that point, we bring the baby back
to the nursery and before we obtain the blood spots we put the pulse oximetry
probes on the baby and perform the screening tests at that time. It's
recommended to wait until after 24 hours for the blood spot collection. And in
addition, if we delay the pulse oximetry screening beyond 24 hours we minimize
the risk of having a false positive result. That is the time point at which we
do the screening.
How much is the piece of equipment to do it?
Dr. Koppel: The device itself varies according to manufacture, but it's
generally on the order of about $2000 per instrument. The probes may either be
reusable or disposable probes. And the guidance from national agencies is that
either is acceptable. There can be significant cost savings by using reusable
probes that just need to be wiped down with alcohol between patients. Other
hospitals however choose to go with disposable probes. So by using reusable
probes the per patient cost works out to approximately 50 cents, and disposable
probes range between six to thirteen dollars each.
And these are something that you would bill to insurance or if they don't have
insurance, the patient would be charged for it? How much is it for the test to
Dr. Koppel: National agencies are currently working with the insurance industry
to try to develop an appropriate system for billing for this procedure. In the
meantime, governments have mandated that the screening be performed, and it
often becomes an unfunded mandate which hospitals pick up. But then hospitals,
in all likelihood, transfer this into other patient costs. There was a paper
that appeared in a pediatrics journal paper out of the CDC that illustrated how
cost-effective pulse oximetry screening is compared to many others screening
mortalities. And in fact, of the costs per patient to perform the screen and
the cost per quality life year that saved by detecting heart defects, the
performance of pulse oximetry as a screening test is extremely favorable.
So you weren't surprised?
Dr. Koppel: That's right. The report came as no surprise because the test is so
easy to administer at such a low-cost with excellent performance
characteristics in terms of sensitivity and specificity. The treatment is so
effective at saving lives that it was very obvious from the outset that the
cost-effectiveness data would be favorable. Having said that I should point out
that in metropolitan regions pediatric echocardiography is widely available.
There have always been concerns voiced about implementing this type of
screening in suburban and rural locations across the country where pediatric
echocardiography may not be as easily available and where abnormal pulse
oximetry screening test may require ambulance transport of the patient to a
larger center. But these fears are turning out to be unwarranted because the
data is being collected from programs all across the country, indicating that
it's in fact very rare for a baby to have to move by ambulance. And the few
babies that are moved by ambulance do turn out, in the vast majority of cases,
to have a critical congenital heart defect that would have required transport
even if the baby had become symptomatic.
How much of a lifesaver is the pulse oximetry?
Dr. Koppel: It's difficult to know because up until this point, where pulse
oximetry screening has now been recommended for wide split--widespread
implementation, the data collection mechanisms have been somewhat incomplete.
But we have estimates that the number of lives that we can expect to be saved
each year in the United States with universal pulse oximetry screening will be
somewhere between 20 and 100 babies saved each year. That is, protection of
somewhere between 20 and 100 babies from death, but that doesn't include the
expected number of babies who will be protected from severe neurologic injury
among survivors of the late diagnosis of critical congenital heart disease.
What's the downside of pulse oximetry?
Dr. Koppel: Well the downside is that it is not yet at a point where it's able
to detect all types of critical heart disease. The one that is most common is a
condition called coarctation of the aorta where there's a narrowing in the
aorta and we're only able to find about half of those cases using our current
method. So there is the need for ongoing research to develop additional tests
to improve our sensitivity for finding babies with coarctation. The only other
downside is that, like any other screening tests there is the risk of a false
positive where we think that the baby has disease but ultimately we do
electrocardiogram in find out, in fact, there is no disease. And conversely,
there's a risk of a false negative where, as in the case of coarctation, the
test results are normal but the baby still has the disease that has gone
Anything else you want to add?
Dr. Koppel: Well, I would simply say that we're at a point we are able to do so
much for babies who have congenital heart disease. And it's very disappointing
if we have a baby that has fallen through multiple layers of safety in terms
of detection of the critical heart defect. We have a duty to diagnose. And if
there's anything that we can do to improve our clinical abilities and we have
to overcome this idea that we're outstanding clinicians that can detect lewd
discoloration using our eyes only. So we need the help of the pulse oximeter as
an instrument that aids in the detection of low oxygen levels.
This information is intended for additional research purposes only. It is not
to be used as a prescription or advice from Ivanhoe Broadcast News, Inc. or any
medical professional interviewed. Ivanhoe Broadcast News, Inc. assumes no
responsibility for the depth or accuracy of physician statements. Procedures or
medicines apply to different people and medical factors; always consult your
physician on medical matters.
If you would like more information, please contact:
Robert Koppel, MD
Regional Perinatal Center
Cohen Children's Medical Center of New York
Associate Professor of Pediatrics
Hofstra North Shore - LIJ School of Medicine