Persistent Pulmonary Hypertension in the Newborn
Overview
Persistent pulmonary hypertension
(PPHN) happens in newborn babies. It occurs when a newborn’s circulation continues
to
flow as it did while in the uterus. When this happens, too much blood flow bypasses
the
baby’s lungs. This is sometimes called persistent fetal circulation.
During pregnancy, a baby's lungs
don’t exchange oxygen and carbon dioxide. So the baby's lungs need only a small amount
of blood to keep the tissues healthy. A baby's circulation sends most of the blood
away
from the lungs. It sends it through connections in the heart and large blood
vessels.
After babies are born, this circulation changes when they start to breathe air. The
change in pressure in their lungs helps close those fetal (prebirth) connections.
This redirects blood flow so that blood is pumped to their lungs. This helps with
the exchange of oxygen and carbon dioxide.
If a newborn has low oxygen levels or trouble breathing, these normal changes may
not happen. This causes the baby's circulation to continue to direct the blood away
from the lungs. The blood pressure in the baby’s lungs stays high. This is PPHN.
Causes
PPHN can happen because of problems
with the blood vessels in the lungs. They can be underdeveloped or abnormally
developed. Or the vessels can have trouble adjusting to the outside air after birth.
It
can be hard to tell right away which of these is the cause.
Risk Factors
A baby who has a difficult birth or birth asphyxia may be more likely to get PPHN.
Birth asphyxia is a condition caused by too little oxygen.
About 1 in every 500 to 700 babies
gets PPHN. It happens most often in full-term babies or babies born after their due
dates.
PPHN is more likely in babies whose
mothers took certain medicines late in pregnancy. These include nonsteroidal
anti-inflammatory drugs (NSAIDs) and selective serotonin receptor inhibitors.
Babies with infections such as pneumonia, or problems with the heart, lungs, or both
are also more likely to have PPHN.
Symptoms
Symptoms can occur a bit differently in each child. They can include:
- Looks sick at birth or in the first hours after birth
- Lips and skin look blue (cyanosis)
- Fast breathing
- Fast heart rate
- Low blood oxygen levels while getting 100% oxygen
The symptoms of PPHN may be similar
to symptoms of other conditions. Make sure your child sees their healthcare provider
for
a diagnosis.
Diagnosis
Your baby’s healthcare provider
will check their health and delivery history. Then the healthcare provider will give
your baby an exam. Your child may need these tests to diagnose PPHN:
-
Chest X-ray. This can show certain problems with the lungs
or heart.
-
Blood tests. These may include arterial blood gas levels,
complete blood cell count, electrolytes, and other blood tests.
-
Oxygen level checks. Your baby’s oxygen levels will be
checked at different spots on their body. Your child’s healthcare provider will
compare these levels to check if blood is being circulated to your baby’s lungs.
-
Echocardiogram. This is an ultrasound picture of the heart and blood
vessels. The provider uses this to look at different body structures and to measure
the blood pressure in different areas.
Treatment
The goal of treatment for PPHN is
to increase the oxygen to all of your baby’s body systems. If your baby’s body doesn’t
get enough oxygen, they may have long-term health problems.
Treatment will depend on your child’s symptoms, age, and general health. It will also
depend on how severe the condition is. Treatments may include the following.
Supplemental oxygen
Your baby gets oxygen through a
mask, prongs in the nose, or plastic hood.
Endotracheal (ET) tube
This is the best way to give the
most oxygen possible. A tube is put into your baby's windpipe (trachea). It helps
them breathe.
Mechanical breathing machine (ventilator)
The machine breathes (moves air
in and out of the lungs) for your baby.
Medicine
Some medicines treat infections,
which can happen along with PPHN. Other types of medicine can help your baby’s
muscles and reflexes relax. This helps your baby respond better to the breathing
machine. Other medicines can help the baby's heart keep blood pumping to the
lungs.
Nitric oxide
Your baby can breathe in this gas. This helps to expand the blood vessels in your
baby’s lungs.
Extracorporeal membrane oxygenation (ECMO)
This procedure is done if your
baby doesn’t respond to other care. With ECMO, blood from your baby's veins is pumped
through an artificial lung. Then oxygen is added and carbon dioxide is removed. The
blood is then returned back to your baby. This procedure is done only in certain
specialized neonatal intensive care units.
Complications
When blood is directed away from
your baby's lungs, it’s hard for their lungs to exchange oxygen and carbon dioxide.
Babies with PPHN have low blood oxygen levels even when they breathe air that’s 100%
oxygen. This can cause serious problems. All of your baby’s organs need a regular
supply
of oxygen-rich blood. Your baby’s organs can become damaged if they don’t get enough
oxygen.
Key Points
- PPHN occurs when a newborn’s
circulation continues to flow as it did in the uterus. When this happens, too much
blood flow bypasses the baby’s lungs.
- About 1 in every 500 to 700 babies
gets PPHN. It happens most often in full-term babies or babies born after their due
dates. It often occurs when a baby has a difficult birth.
- Your baby may need tests to check for
this condition. These can include a chest X-ray, blood tests, and oxygen level
checks.
- The goal of treatment for PPHN is to
help move the oxygen to all of your baby’s body systems.
- If your baby doesn’t get enough
oxygen, they may have long-term health problems.
Next Steps
Tips to help you get the most from a visit to your child’s healthcare provider:
- Know the reason for the visit and what you want to happen.
- Before your visit, write down questions you want answered.
- At the visit, write down the name of a
new diagnosis and any new medicines, treatments, or tests. Also write down any new
instructions your provider gives you for your child.
- Know why a new medicine or treatment is prescribed and how it will help your child.
Also know what the side effects are.
- Ask if your child’s condition can be treated in other ways.
- Know why a test or procedure is recommended and what the results could mean.
- Know what to expect if your child does not take the medicine or have the test or procedure.
- If your child has a follow-up appointment, write down the date, time, and purpose
for that visit.
- Know how you can contact your child’s provider after office hours. This is important
if your child becomes ill and you have questions or need advice.