Patent Ductus Arteriosus

Definition

Patent ductus arteriosus (PDA) is an unclosed hole in the heart's aorta.

Before birth, the fetus gets its oxygen from the mother, so the lungs are not used. The ductus arteriosus is a small hole that lets the blood of the fetus bypass lungs. In most babies, the hole closes within a few hours of birth. This is normal. When the hole stays open, blood travels in the wrong direction. This causes too much blood to flow through the lungs.

Patent Ductus Arteriosus.

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Causes

Premature birth is the most common cause. PDA may also be linked to:

• Exposure during pregnancy to infections, such as rubella
• Genetics
• The environment

Risk Factors

This problem is more common in babies who weigh less than usual and are born before 28 weeks of pregnancy. It is also more common in female babies.

The risk is also higher in low birth weight babies with:

• Respiratory distress syndrome
• Stress in the mother before the baby's birth
• Neonatal sepsis
• Low platelet count

Symptoms

A baby with a small PDA may not have symptoms. Babies with a large PDA may have:

• Fast breathing
• Shortness of breath
• Periods of getting tired easily
• Problems feeding
• Poor growth

Diagnosis

This problem is often diagnosed at birth. A physical exam will be done. The doctor will listen for signs of a heart murmur. This is enough to suspect PDA.

Blood tests will be done to look for signs of PDA.

Images may be taken of the baby's chest. This can be done with an echocardiogram.

Treatment

The goal of treatment is to close the PDA. Choices are:

• Fluid restriction for 2 to 3 days to help the hole close on its own
• Medicine to tighten the muscle in the wall of the hole to help it close

Babies who are not helped by these methods may need surgery to close the hole.

Prevention

There are no guidelines to prevent PDA.