Persistent pulmonary hypertension (PPHN) happens in newborn babies. It occurs when a newborn’s circulation continues to flow as it did while in the womb. When this happens, too much blood flow bypasses the baby’s lungs. This is sometimes called persistent fetal circulation.
During pregnancy, a fetus' lungs don’t exchange oxygen and carbon dioxide. So the fetus only needs a small amount of blood to keep the tissues healthy. A fetus' 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.
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 difficulty adjusting to the outside air after birth. It can be very hard to tell right away which of these is the cause.
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 one in every 1,250 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 non-steroidal anti-inflammatory medicines 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 can occur a bit differently in each child. They can include:
The symptoms of PPHN may be similar to symptoms of other conditions. Make sure your child sees his or her healthcare provider for a diagnosis.
Your baby’s healthcare provider will check his or her health and delivery history. Then he or she will give your baby an exam. Your child’s healthcare provider may do the following tests to diagnose PPHN:
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, he or she 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.
Your baby gets 100% oxygen through a mask, prongs in the nose, or plastic hood.
This is the best way to give the most oxygen possible. A tube is put into your baby's windpipe (trachea). It helps him or her breathe.
The machine breathes for your baby.
Some medicines treat infections, which can happen along with PPHN. Other types of medicine can help your baby’s muscles and reflexes relax. This makes your baby respond better to the breathing machine. Other medicines can help the baby's heart keep blood pumping to the lungs.
Your baby can breathe in this gas. This helps to expand the blood vessels in your baby’s lungs.
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 only done in certain neonatal intensive care units.
When blood is directed away from your baby's lungs, it’s hard for his or her 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.
Tips to help you get the most from a visit to your child’s healthcare provider: