Persistent Pulmonary Hypertension of the Newborn

Sometimes the blood vessels to the lungs do not dilate after birth as they normally should. When the blood vessels to the lungs do not dilate, blood pressure in the pulmonary arteries is too high (pulmonary hypertension Pulmonary Hypertension Pulmonary hypertension is a condition in which blood pressure in the arteries of the lungs (the pulmonary arteries) is abnormally high. Many disorders can cause pulmonary hypertension. People... read more ), and blood flow to the lungs is insufficient. Because of this insufficient blood flow, not enough oxygen reaches the blood.

There are many reasons the blood vessels may not dilate, including

Persistent pulmonary hypertension of the newborn is more common among newborns who are full term (delivered between 37 weeks and 42 weeks of gestation Gestational age Problems in newborns may develop Before birth while the fetus is growing During labor and delivery After birth About 9% of newborns need special care after birth due to prematurity, problems... read more ) or postterm Postterm Newborns A postterm newborn is a baby delivered after 42 weeks of gestation. Near the end of a term pregnancy, the function of the placenta decreases, providing fewer nutrients and less oxygen to the... read more (delivered after 42 weeks of gestation).

Sometimes persistent pulmonary hypertension is present from birth. Other times, it develops over the first day or two.

Breathing is usually rapid, and there may be severe respiratory distress if the newborn has an underlying lung disorder (such as respiratory distress syndrome). The skin and/or lips may have a bluish discoloration (cyanosis Cyanosis Cyanosis is a bluish discoloration of the skin resulting from an inadequate amount of oxygen in the blood. Cyanosis occurs when oxygen-depleted (deoxygenated) blood, which is bluish rather than... read more ) due to low blood oxygen levels. Sometimes newborns with persistent pulmonary hypertension have low blood pressure Low Blood Pressure Low blood pressure is blood pressure low enough to cause symptoms such as dizziness and fainting. Very low blood pressure can cause damage to organs, a process called shock. Various drugs and... read more (hypotension) that causes weak pulses and a pale, grayish hue to the skin.

Doctors may suspect persistent pulmonary hypertension if the mother took high doses of aspirin or indomethacin during pregnancy or had a stressful delivery. They also suspect persistent pulmonary hypertension if the newborn has severe respiratory distress, cyanosis that does not go away when high concentrations of supplemental oxygen are given, and unexpectedly low oxygen levels in the blood. Doctors may also suspect persistent pulmonary hypertension in newborns who have meconium aspiration syndrome, who may have an infection, or who need more oxygen or breathing support than expected.

To confirm the diagnosis of persistent pulmonary hypertension of the newborn, doctors do an echocardiogram Echocardiography and Other Ultrasound Procedures Ultrasonography uses high-frequency (ultrasound) waves bounced off internal structures to produce a moving image. It uses no x-rays. Ultrasonography of the heart (echocardiography) is one of... read more to see how blood flows through the heart and to the lungs.

A chest x-ray may be entirely normal if there is no underlying lung disorder or may show changes caused by an underlying disorder (such as diaphragmatic hernia or meconium aspiration syndrome).

Cultures of the blood may be done to look for certain kinds of bacteria.

About 10 to 60% of affected newborns die depending on the cause of the persistent pulmonary hypertension.

About 25% of survivors have developmental delays, hearing problems, functional disabilities (meaning a decreased ability to do physical activities), or a combination.

Treatment of persistent pulmonary hypertension of the newborn involves placing newborns in an environment with 100% oxygen. In severe cases, a ventilator Mechanical Ventilation Mechanical ventilation is use of a machine to aid the movement of air into and out of the lungs. Some people with respiratory failure need a mechanical ventilator (a machine that helps air get... read more (a machine that helps air get in and out of the lungs) providing 100% oxygen may be needed. A high percentage of oxygen in the blood helps open the arteries going to the lungs.

A very small concentration of the gas nitric oxide may be added to the oxygen that the newborn is breathing. Inhaled nitric oxide opens the arteries in the newborn’s lungs and reduces pulmonary hypertension. This treatment may be needed for several days.

Rarely, if all other treatments do not work, extracorporeal membrane oxygenation (ECMO) can be used. In this procedure, blood from the newborn is circulated through a machine that adds oxygen and removes carbon dioxide and then returns the blood to the newborn. The machine acts as an artificial set of lungs for the newborn. As the machine does the work of getting oxygen into the newborn's body, the newborn's lungs have time to rest and the blood vessels slowly open up. ECMO has been lifesaving, allowing some newborns with pulmonary hypertension who do not respond to other treatments to survive until the pulmonary hypertension resolves.

Fluids and other treatments, such as antibiotics for an infection, are given as needed.