Management of Patent Ductus Arteriosus (PDA) in Premature Babies

The most prevalent cardiac ailment for neonates is patent ductus arteriosus (PDA). Cardiologists, surgeons, and neonatologists disagree sharply about whether to treat the PDA, even though the issue has been the subject of numerous studies and thousands of publications. There are still differences in practice between subspecialties and centers.

An overview of the PDA’s symptoms, risk factors, and management is provided in this article. While not quite a paradigm shift, it also briefly addresses the hemodynamic significance of a PDA and provides a framework for a review of all the literature on PDA closure in premature infants.

What is Patent Ductus Arteriosus (PDA) in Premature Babies?

Patent Ductus Arteriosus (PDA) is a condition of the heart that can affect premature babies. Before birth, the ductus arteriosus is a standard blood vessel connecting the pulmonary artery to the aorta, allowing blood to bypass the lungs because the fetus receives oxygen from the mother’s placenta. However, this connection usually closes shortly after birth in a full-term baby.

In premature babies, the ductus arteriosus may fail to close independently, leading to a condition called Patent Ductus Arteriosus. When the ductus arteriosus remains open, it can disrupt average blood circulation, causing problems such as increased blood flow to the lungs and potentially overloading the heart.

What are the symptoms of Patent Ductus Arteriosus (PDA)?

Patent Ductus Arteriosus (PDA) is a heart condition that occurs when the ductus arteriosus, a blood vessel that connects the pulmonary artery and the aorta in a fetus, fails to close after birth. The symptoms of PDA can vary, and not everyone with PDA will experience the same signs. Common symptoms may include:

• A persistent heart murmur, an abnormal sound caused by the turbulent flow of blood through the open ductus arteriosus.
• Infants with PDA may experience difficulty during feeding, as they may tire quickly or become breathless.
• Infants with PDA may have difficulty gaining weight due to the increased workload on the heart.
• Rapid breathing or shortness of breath may occur, especially during physical activity.
• Children with PDA may tire quickly and seem more fatigued than their peers.
• There may be an increased susceptibility to respiratory infections.

It’s important to note that some individuals with PDA may not exhibit noticeable symptoms, and the condition may be discovered incidentally during a routine physical examination. If PDA is suspected, a healthcare professional, usually a pediatric cardiologist, can conduct diagnostic tests such as echocardiography to confirm the diagnosis and determine the severity of the condition. Early detection and appropriate management are crucial for the best outcomes.

What are the Factors of PDA in Premature Babies?

The incidence of PDA is inversely associated with the degree of prematurity. Factors of PDA in Premature Babies include:

• Sepsis
• High volume of intravenous fluids (>170 mL/kg per day) in the first week
• Respiratory distress syndrome
• Prolonged rupture of membranes
• Furosemide
• Male sex

Evidence also shows that aminoglycoside antibiotics and certain antacids, frequently used in neonates, paradoxically increase the risk of a PDA. Antenatal corticosteroids and maternal hypertension decrease the incidence of PDA. The effect of antenatal corticosteroids on the closure of the ductus arteriosus is independent of their impact on lung maturation. It is most beneficial to administer corticosteroids at least 24 hours before delivery. Exogenous surfactant does not directly affect the ductus arteriosus but can unmask a patent ductus by decreasing the pulmonary vascular resistance, thus allowing for increased left-to-right shunting.

How to manage Patent Ductus Arteriosus (PDA) in Premature Babies?

Managing Patent Ductus Arteriosus (PDA) in premature infants involves a comprehensive approach, considering various factors to determine the need for intervention. The gold standard for diagnosing and assessing the hemodynamic significance of PDA is transthoracic echocardiography. However, there is no consensus on specific criteria defining the need for closure, and the approach involves a combination of clinical and echocardiographic variables.

Determinants of Risk for Hemodynamically Significant PDA (hsPDA):

• Ductal diameter ≥1.5 mm within the first hours of life predicts symptomatic PDA in infants ≤28 weeks gestational age.
• Other echocardiographic variables include an LA-to-aortic root ratio ≥1.4, LV enlargement, increased mean, diastolic PA flow velocities, reversed mitral E/A ratio, and indicators of systemic hypoperfusion.
• Individual risk factors such as gestational age, chronological age, and comorbidities should be considered.

Pharmacologic Ductus Closure:

• Intravenous indomethacin has traditionally been the mainstay for pharmacotherapy, focusing on prophylactic, early, or symptomatic treatment.
• Newer regimens include oral and intravenous ibuprofen and oral and intravenous paracetamol.
• Ibuprofen is preferred for its superior safety profile, especially in severely preterm infants, and has shown effectiveness in prevention and treatment.

Paracetamol (Acetaminophen):

• Paracetamol is considered in cases where COX inhibitors are contraindicated or ineffective.
• Studies suggest effectiveness comparable to ibuprofen but with a lower initial constriction rate.

Timing of Pharmacologic Treatment:

• Prophylactic use of indomethacin is considered, especially in units with a low spontaneous closure rate, although the long-term benefits are not well established.
• Early targeted treatment (<6 days) is recommended for infants with a significant shunt and respiratory support.
• Treatment of symptomatic infants with hsPDA should be considered based on echocardiographic and clinical variables.
• Late and rescue treatment options include paracetamol after failed COX inhibitor treatment.

Catheter-Based Interventional Closure:

• The Amplatzer Piccolo Occluder device has received FDA approval for PDA closure in premature infants weighing ≥700 g.
• Catheter-based closure provides a nonsurgical alternative with potential benefits over surgical ligation, but long-term outcomes and optimal use need further study.

Surgical Ligation:

• Surgical ligation rates have decreased, and the timing and benefits of ligation remain uncertain.
• Meta-analyses indicate increased odds of complications such as neurodevelopmental impairment, CLD, and severe ROP with ligation.

Conservative Treatment:

• Conservative management includes a spectrum from no treatment to targeted strategies like fluid restriction and diuretic therapy while waiting for spontaneous closure.
• The PDA-TOLERATE trial suggests that conservative management may be beneficial in select settings.

Comprehensive Approach:

• A treatment algorithm incorporates early targeted prophylaxis, targeted therapy of asymptomatic infants, symptomatic treatment of hsPDA, and late/rescue treatment options.
• Recommendations are based on expert opinion and may require adaptation to local practices and unit-specific factors.

Managing PDA in premature infants involves a nuanced and individualized approach, considering both clinical and echocardiographic parameters to determine the need for intervention and the choice of pharmacotherapy or procedural closure. Ongoing research is needed to refine guidelines and optimize outcomes for these vulnerable neonates.

Conclusion

Patent Ductus Arteriosus (PDA) in premature infants is a contentious issue among healthcare specialists, with disagreement persisting on the necessity of treatment due to limited long-term benefits from available interventions. This heart condition arises when the ductus arteriosus, a fetal blood vessel, fails to close after birth, potentially disrupting average blood circulation. Symptoms vary but may include heart murmurs, feeding difficulties, poor weight gain, rapid breathing, fatigue, and increased susceptibility to respiratory infections. Factors contributing to PDA in premature infants include prematurity degree, respiratory distress syndrome, high fluid volumes, sepsis, and other variables. Management involves a comprehensive approach, utilizing diagnostic tools such as echocardiography and considering factors like ductal diameter, echocardiographic variables, and individual risk factors. Treatment options range from pharmacologic closure using indomethacin, ibuprofen, or paracetamol to catheter-based interventions and surgical ligation. A conservative approach may also be considered in specific cases. The nuanced management requires ongoing research for guideline refinement and improved outcomes for these vulnerable neonates.

For comprehensive information on the management of Patent Ductus Arteriosus (PDA) in premature infants, including detailed insights into treatment options, guidelines, and the latest research, you can explore https://medigence.com/hospitals/cardiac-sciences/pda-closure/india Medigence provides valuable resources to help you find the best hospitals, experienced doctors, and up-to-date medical information, ensuring you make informed decisions about the care and treatment of premature infants with PDA.