448 - Analysis of factors related to pulmonary hypertension diagnosis in a severe bronchopulmonary dysplasia population at a level IV referral NICU

Poster Number: 448
Publication Number: 448.3143

Background: Bronchopulmonary dysplasia-associated pulmonary hypertension (BPD-PH) is a major contributor to morbidity and mortality in severe BPD (sBPD). Recommendations for PH screening in sBPD include echocardiogram at 36 wk postmenstrual age (PMA) and every 1-2 mo thereafter. In late 2019, Phoenix Children’s developed a structured BPD program, including monthly PH screening. Over time, the rate of BPD-PH in our program is decreasing (Figure 1).

Objective: Describe infant characteristics and practice variables related to diagnosis of PH and compare in-hospital outcomes based on diagnosis of PH ≥ 36 wks PMA.

Design/Methods: Retrospective review of infants born < 32 wks gestation with Grade 2 and 3 BPD and admitted to the Phoenix Children’s NICU between 2020-2023. A PH diagnosis was given if at or after 36 wks PMA, echocardiographic evidence of right ventricular systolic pressure > ½ of systemic was present. Clinical characteristics, PH practice, and outcomes variables were evaluated using univariate comparisons and bivariate and multivariate logistic regression (included variables with bivariate p< 0.2).

Results: Infants with PH (n=29) versus without PH (n=60) had lower median birth weight (BW), BW z-score, 0.96 (-1.4, 0.11) vs-0.13 (-0.93, 0.59), were admitted to PCH at a greater median chronologic age (CA), 98 (56, 114) vs 58 (34, 86) days, and PMA 39.9 (34.1, 42.6) vs 34.4 (32.4, 39.4) weeks and had greater respiratory severity score (RSS) on admission 5.2 (2.6, 10.2) vs 3.6 (2.4, 5.6). Infants with PH more often had grade 3 BPD and transfer for BPD management. Echocardiograms for those with PH were obtained earlier, in greater quantity and frequency compared to those without PH (Table 1). Infants with PH were more likely to receive tracheostomy (58% vs 30%) and have longer median length of stay (LOS) 124 (99, 217) vs 99 (67, 130) days. Of the 3 infants who died, all had PH. Length and weight Z scores at discharge were not different between groups. Multivariate logistic regression analysis for risk factors was only significant for BW Z-score, 0.48 (0.26-0.86), while for outcomes, regression showed greater number of echocardiograms was significantly associated with diagnosis of PH, 1.4 (1.18-1.8), (Table 2).

Conclusion(s): Individually many factors were associated with increased odds of BPD-PH, but after adjusting for all factors, only lower BW Z-score and number of echocardiograms during stay were significantly associated with BPD-PH. We speculate that improved respiratory support delivery as our BPD program matures may relate to reduced rate of PH, although further consideration of additional factors is needed.