Bronchopulmonary dysplasia (BPD) continues to be a common yet challenging condition affecting premature newborns. “This is a multifactorial and heterogeneous disease that is quite complex to manage as not all babies who are affected by BPD have the same manifestations or follow the same course of illness,” says Lauren A. Sanlorenzo, MD, MPH, a neonatologist with the Division of Neonatology at NewYork-Presbyterian/Columbia and NewYork-Presbyterian Morgan Stanley Children’s Hospital. “This disease requires timely identification, stratification of disease severity, involvement of various specialists as dictated by the course of illness, and input from developmental therapists and families”.
Premature birth is the primary risk factor for the development of BPD. Babies born less than 32 weeks gestation, are at risk for the development of bronchopulmonary dysplasia. The vast majority of those affected with the more severe phenotypes are infants born <27 weeks gestation. A 2019 pragmatic definition of BPD categorized disease according to the mode of respiratory support the infant was receiving at 36 weeks postmenstrual age (PMA). Infants on mechanical ventilation at 36 weeks PMA were categorized as Grade III BPD, the most severe form. Infants on >2 liters per minute of nasal cannula flow or any noninvasive positive pressure were categorized as Grade II BPD. A diagnosis of GII or GIII BPD was associated with higher rates of death or severe respiratory morbidity at 2 years corrected age.
“Other factors can influence the likelihood of an infant developing bronchopulmonary dysplasia, such as prolonged need for mechanical ventilation, sepsis, surgical necrotizing enterocolitis, or persistent patent ductus arteriosus notes Dr. Sanlorenzo. “The model for our BPD consult team is to identify infants born less than 32 weeks who meet criteria for Grade II or Grade III BPD at 36 weeks PMA. This time point allows us to more formally categorize disease using current standard definitions of BPD. At this time point we meet the infant, obtain a screening echocardiogram of the heart to assess the pulmonary vasculature, and take a holistic approach to the infants’ overall growth, pulmonary, and developmental trajectory.”.
“One of the things our team does at the time of diagnosis is take a comprehensive look back at the hospital course to date to ensure we have a global understanding of the patients NICU course.” continues Dr. Sanlorenzo. "It is important for our team to identify any known risk factors for the development of BPD assess for complications associated with BPD like pulmonary vein stenosis and pulmonary hypertension.”
According to Dr. Sanlorenzo, factors that are key to evaluate include:
- Growth curve – A close look at growth history in-utero, the presence of fetal growth restriction, or small for gestational age status at birth helps to know where the patient started. From there, assessment of growth trajectories in the NICU using preterm growth curves.
- Infectious History- Our team looks back to see if the patient as history of documented bacterial or viral infections in the NICU, including those outside of the lung such as necrotizing enterocolitis or sepsis which are known risk factors for BPD.
- Review of prior echocardiograms, pulmonary imaging such as chest x-rays or CT scans can be helpful to assess lung tissue and pulmonary vascular disease. Given the association between prolonged patency of the ductus arteriosus (PDA) the consult team assess the status and prior treatment aimed at the PDA.
Establishing a BPD Consult Team
One year ago, Dr. Sanlorenzo, along with NewYork-Presbyterian/Columbia colleagues Alexandra Kass, MD, a pediatric pulmonologist, and Usha S. Krishnan, MD, a pediatric cardiologist, established the BPD Consult Team to provide continuity among specialists in managing the current medical needs as well as ongoing care of the infants.
“BPD doesn’t end when the babies are discharged from the NICU,” notes Dr. Sanlorenzo. “There are lifelong respiratory complications associated with BPD.” The consult team seeks to connect families to the support they need, allowing them to meet pulmonary medicine and cardiologist who will follow them as outpatients.
A unique aspect of the BPD team is the expertise provided by Dr. Krishnan, who is internationally renowned in the management of infants with pulmonary hypertension (PH). BPD associated PH is a particularly challenging complication of BPD. Dr. Krishnan serves as the Associate Medical Director of the Pediatric Pulmonary Hypertension Center at Columbia, the first accredited pediatric and adult pulmonary hypertension center in the United States.
“BPD not only affects the development of the lung tissue itself, but also the microvasculature that is critical for the healthy development and functionality of the lungs,” explains Dr. Sanlorenzo. “When the pressure inside the lungs is altered because of BPD – known as BPD-associated pulmonary hypertension, or if an infant is found to have pulmonary vein stenosis, a rare but serious complication of BPD, our team relies on Dr. Krishnan and cardiac interventionalists to help tailor medication and interventions. Having these specialists involved in our program enables us to address the most severe complications related to BPD.”
One of the goals of the BPD Consult Team is to leverage quality improvement methodology focused on the prevention and treatment of BPD – an initiative that Dr. Sanlorenzo helped to launch while she was a member of the Division of Neonatology at Vanderbilt University Medical Center. Along with Vanderbilt colleague, L. Dupree Hatch III, MD, MPH, Dr. Sanlorenzo co-authored an article published in Clinics in Perinatology in June 2023 describing their efforts to develop a QI program at Vanderbilt and providing other centers with a comprehensive roadmap to create similar programs.
Determining What Interventions and When
Many decades of research have shown that innovations in neonatal respiratory care have improved survival rates and lowered morbidities for infants in the NICU. Over the years, many interventions – from mechanical and non-mechanical ventilation to a range of pharmacological therapies – have been introduced for the treatment of bronchopulmonary dysplasia.
Ventilation
NewYork-Presbyterian Morgan Stanley Children’s Hospital was among the first to use CPAP with premature infants and demonstrate a correlation between the use of non-invasive respiratory support and low rates of BPD.
“When thinking about optimal interventions to prevent BPD, it begins in the delivery room where we can establish lung volume and optimize the newborn’s health with their first few breaths,” says Dr. Sanlorenzo. While mechanical ventilation is sometimes needed and can be lifesaving, it also does damage to premature lungs. Columbia has always been at the forefront of the predominant use of non-invasive ventilation, specifically bubble CPAP, to minimize the amount of time that babies spend on mechanical ventilation.
Medications
“Selecting an effective pharmacologic intervention for bronchopulmonary dysplasia is challenging, as there is limited evidence to inform our use of many classes of medications in this population. We know that infants with severe BPD are exposed to many medications during their hospital courses yet we don’t have good evidence to pinpoint what patients are most likely to benefit from which medication”. Several common classes of medications that are used in infants with BPD are diuretics, steroids, and bronchodilators. We aim to use short trials of a given medication and monitor for objective improvement in clinical characteristics such as respiratory rate, work of breathing, or oxygen needs. Other times imaging can inform decisions around pharmacotherapy”.
“For example, we often evaluate the lung fields around the time of BPD diagnosis with a chest x-ray to assess lung inflation. This can help us see how the mode of respiratory support is maintaining the lungs and keeping the airspaces open to support oxygenation and gas exchange,” continues Dr. Sanlorenzo. “We also look for general haziness in the lungs, which can be a sign of pulmonary edema. We will use imaging, clinical status, and the findings from a screening echocardiogram, to guide us in selecting the most appropriate medications or interventions.”
Dr. Sanlorenzo emphasizes that many medications, such as diuretics or steroids, are nonspecific. While they can have a positive effect on pulmonary health for certain patients, they have side effects that can be significant and must be considered when selecting medical therapies. The BPD Consult Team monitors and tracks medication exposure and takes an individualized approach to pharmacotherapy. “We dedicate time and attention to this delicate balance with every patient.”
BPD Collaborative
Ten years ago, a group of neonatologists and pulmonologists from seven major children’s hospitals met to discuss how to improve outcomes for patients with established severe BPD. From that first meeting, the BPD Collaborative was created, and today has grown to 27 participating hospitals and 205 clinicians spanning 20 different disciplines. The mission of the BPD Collaborative is to foster “interdisciplinary collaboration and innovation in the identification and treatment of these highly vulnerable patients.” This includes sharing data, developing and implementing quality improvement initiatives, and facilitating research protocols to address the most pressing knowledge gaps with a goal to improve the life-long outcomes of babies who develop severe BPD.
NewYork-Presbyterian recently became a member of the BPD Collaborative. “By partnering with the BPD Collaborative, we are able to engage in larger multicentered studies that are focused on understanding disease trajectories and novel therapies,” says Dr. Sanlorenzo. “With our expertise in CPAP, I believe NYP will add value to the larger conversation about BPD prevention.”
Engaging Families Early and Often
Infants with severe BPD have long hospital courses, as these infants are often born very premature and have respiratory needs that require long NICU stays. “Involving families at the time of diagnosis and through the transition to home is critical to our program,” notes Dr. Sanlorenzo. “We want to ensure that families understand the diagnosis of bronchopulmonary dysplasia, are aware of expectations for treatment and outcomes, and know they are valued partners in the care team. We aim to support families during the NICU stay and provide continuity with the pediatric pulmonologist in the outpatient setting. Our consult team provides continuity when infants are readmitted to the hospital after NICU discharge, a common occurrence for infants with more severe disease. “Central to our work is the goal of empowering families to understand BPD and how to help their child live their fullest life.”
