164 - Does BPD definition influence postnatal steroid use?

Poster Number: 164
Publication Number: 164.438

Pradeep Alur, University of Mississippi Medical Center, Camp Hill, PA, United States; Ira Holla, University of Mississippi Medical Center, Jackson, MS, United States; Addie Hitt, University of Mississippi School of Medicine, Jackson, MS, United States; Simmy Vig, University of Mississippi School of Medicine, Jackson, MS, United States

Background: There is no universally accepted Bronchopulmonary Dysplasia (BPD) definition currently. The Neonatal research network (NRN) published the BPD risk calculator online in 2011 (C1). it was based on NIH consensus definition- mild BPD- O2 > than or equal to 28 days but not at 36 weeks; moderate BPD- O2 > than or equal to 28 days + less than 30% O2 at 36 weeks; and severe BPD- O2 > than or equal to 28 days + > than/= to 30% O2 or positive pressure at 36 weeks. Vermont Oxford Network (VON) still uses this definition.

In 2022 NRN revised the calculator (C2) based on the mode of respiratory support at 36 weeks’ PMA, regardless of the use of supplemental oxygen. Grade 1 BPD on nasal cannula ≤2L/min; grade 2 BPD as nasal cannula >2L/min, CPAP, or nasal intermittent positive pressure ventilation; and grade 3 BPD as invasive mechanical ventilation. NRN provides both calculators on its website. Clinicians use the calculator to verify the benefits of postnatal steroids (PNS) based on Doyle's study in 2014. Since VON relies on older BPD definition, it is important to evaluate if the PNS eligibility is comparable with the newer calculator.

Objective: To evaluate if PNS use will be higher using the 2011 NRN BPD calculator.

Design/Methods: We have used 26 actual clinical cases to compare the BPD risk estimates using C1 and C2 BPD risk calculators. (figure1). The PNS are beneficial if the combined BPD/death risk is >60% or if the combined death/severe BPD is >37%. Using these criteria, we compared the BPD estimates from both calculators and analyzed them with a 2-tail student T-test with a priori significance of p = < 0.05. The sample size needed was 24 with 80% power for the observed differences.

Results: The estimated combined BPD/death risk of >60% was higher with the C1 (77% of the cases) compared to 23% with the C2 (figure 1). The p-value was < 0.005. Similarly, C1 estimated the combined death/severe BPD risk to be >37% in 92% of the cases, which is significantly more than that predicted by the C2 calculator (0%) p = < 0.00001. Figure 2. With C1, a white female on CPAP will exceed 60% risk at 58% FiO2, whereas a black female will do so at 80% (Figure 3). Race is not a variable in the C2 calculator.

Conclusion(s): The definition of BPD can significantly influence the eligibility for PNS usage. The widely used definition of BPD may significantly increase the risk of exposure of preterm infants to PNS & can be significantly affected by race. Clinicians should be aware that different estimates for BPD risk depend on the criteria for BPD definition. Future studies to validate the use of PNS based on calculators are needed.