Persistent Pulmonary Hypertension in the Neonate (PPHN)

What is PPHN?

Persistent pulmonary hypertension of the newborn, or PPHN, is a serious breathing problem in newborns. It occurs when your newborn’s circulatory system doesn’t adapt to breathing outside of your uterus.

While in your uterus, the fetus gets oxygen through the umbilical cord and placenta. Very little blood goes to the fetal lungs because the blood vessels in the lungs (pulmonary arteries) are mostly closed. Blood bypasses the lungs and flows to the rest of the body.

After your baby is born and takes their first breath, the blood vessels of their lungs should open. Air brings oxygen into their lungs. The blood vessels then allow blood to travel to your baby’s lungs to get the oxygen and deliver it to the rest of their body.

PPHN happens when your newborn’s blood vessels don’t open up enough, which means there’s a limit on how much oxygen reaches your baby’s brain and other organs, such as their heart, kidneys and gut. PPHN is a life-threatening medical emergency that can happen shortly after birth.

How common is this condition?

PPHN occurs in 2 out of every 1,000 live births. It happens most often in full-term babies (born between 37 and 42 weeks) and late-term babies (born after 42 weeks). It occasionally occurs in premature babies, as well.

What are the symptoms?

Symptoms of PPHN may include:

• Breathing problems such as rapid or slow breathing, grunting and retracting.
• Rapid heart rate.
• Bluish color to your baby’s skin (cyanosis).
• Low blood pressure (hypotension).
• Low blood oxygen levels.
• Extra or abnormal heart sounds (heart murmur).

What causes persistent pulmonary hypertension of the newborn?

Researchers don’t know the exact cause of PPHN. However, incorrectly developed or underdeveloped blood vessels in your baby’s lungs — or their inability to adapt (open up) to the outside environment — may cause the condition.

What are the risk factors for PPHN?

Although the cause is unknown, certain factors increase your infant’s risk of developing PPHN. These factors may include:

• Meconium aspiration: This can happen if your baby breathes in their own sticky first poop (meconium).
• Infection: This includes pneumonia and bloodstream infections.
• Respiratory distress syndrome (RDS): This breathing difficulty happens in infants who don’t have fully developed lungs (premature babies).
• Birth asphyxia: Lack of oxygen before or during birth.
• Diaphragmatic hernia: This refers to a hole in your baby’s diaphragm, which is the muscle that keeps their chest separate from their belly (abdomen). A hernia is when organs from one side push through the hole — in this case, organs from their abdomen intrude on their chest.
• Other congenital (present at birth) heart and lung abnormalities: Such as lungs that are smaller than they should be or a blocked heart valve.
• Taking certain medications during pregnancy: Taking medications such as nonsteroidal anti-inflammatory drugs (NSAIDs) and selective serotonin receptor inhibitors (SSRIs) during late pregnancy may have an effect.

What are the long-term effects of PPHN?

Up to 1 in 4 babies who survive PPHN will have some impairment due to a lack of oxygen reaching their brains. These complications may include:

• Developmental delays.
• Hearing issues such as deafness.
• Learning disabilities.
• Decreased ability to perform physical activities.

How is PPHN diagnosed?

Your infant’s healthcare provider may use various laboratory and imaging tests to diagnose PPHN, including:

• Complete blood count(CBC): A CBC measure’s your baby’s white blood cells, red blood cells and platelets.
• Pulse oximetry (pulse ox): Pulse oximetry is a noninvasive way to measure oxygen levels in your baby’s blood.
• Arterial blood gas (ABG): ABG determines how well your baby’s body delivers oxygen.
• Chest X-ray: A chest X-ray can determine if your baby has an enlarged heart or lung disease.
• Echocardiogram(echo): An echocardiogram is a detailed ultrasound of your baby’s heart, which helps evaluate blood flow to their heart and lungs.
• Head ultrasound: An ultrasound of your baby’s head that helps to look for bleeding in their brain.
• Serum electrolyte tests: Your baby’s provider can use serum electrolyte tests to evaluate the balance of minerals in your baby’s blood.
• Lumbar puncture (spinal tap): A lumbar puncture can help determine if your baby has an infection.

How is PPHN treated?

The main goal of treatment for PPHN is to increase oxygen flow to your baby’s organs to prevent serious complications. Treatment may include a variety of options, including:

• Oxygen: Your baby may receive 100% supplemental oxygen through nasal cannula, nasal prongs or a mask.
• Mechanical ventilation: A healthcare provider will insert a tube into your baby’s windpipe (trachea). The ventilator breathes for your baby.
• Blood pressure support: Your baby may be given blood pressure medicine intravenously (IV or through a vein).
• Nitric oxide: Nitric oxide is a gas that helps open up (dilate) the blood vessels in your baby’s lungs. It also improves blood flow to their lungs.
• High-frequency oscillatory ventilation: This type of ventilation may help improve the oxygen level in your baby’s blood.
• Extracorporeal membrane oxygenation (ECMO): If your baby is experiencing serious heart or lung failure, healthcare providers may use an ECMO machine, which delivers oxygen to your baby’s brain and body temporarily.

Can PPHN be prevented?

Researchers don’t know why the condition occurs, so you can’t prevent it. However, you can reduce your risk by avoiding certain medications during your pregnancy. Speak with your healthcare provider about which medicines are safe to take during pregnancy.

What is the recovery time for PPHN?

While most cases of PPHN resolve within one to two weeks, some may take longer, sometimes months to recover fully. It’ll be important to help protect your baby from catching colds, the flu and other viruses. You can help with this by practicing good handwashing and keeping your baby away from large crowds and people who are sick. It’ll also help to make sure all household members get their annual flu vaccine. It’ll be especially important for your baby to see their healthcare provider and other specialists regularly to be screened for normal developmental milestones.

What is the survival rate of PPHN?

Between 7% and 10% of newborns with PPHN will die due to complications of the condition. Of those that survive, 25% will experience lasting effects due to a lack of oxygen reaching their brain. These long-term effects may include developmental delays, learning disabilities and hearing problems.

When should my baby see their healthcare provider?

Make sure to bring your baby to all of their follow-up appointments so their healthcare provider can continue to monitor them. In the meantime, seek immediate medical care if your baby:

• Develops a fever.
• Isn’t feeding well.
• Sucks in their chest or flares out their nostrils while breathing.
• Makes wheezing or grunting sounds.
• Begins to turn a bluish or grayish color.