464 - Lung Ultrasound Score as an Indicator of Pulmonary Edema Severity in the Setting of a Hemodynamically Significant Patent Ductus Arteriosus in Extremely Premature Infants

Publication Number: 3449.464

Ashley E. Reeves, The Warren Alpert Medical School of Brown University, Providence, RI, United States; Lynne Dansereau, Women & Infants Hospital of Rhode Island, Providence, RI, United States; Richard Tucker, Women & Infants Hospital of Rhode Island, Providence, RI, United States; Sfurti Nath, Brown University/Women and Infants Hospital of Rhode Island, Providence, RI, United States; Jonathan Nyce, Brown University Health, Providence, RI, United States; Juan Sanchez-Esteban, The Warren Alpert Medical School of Brown University, Providence, RI, United States

Background: Lung ultrasound (LUS) can potentially be used to evaluate pulmonary edema severity in the setting of a hemodynamically significant patent ductus arteriosus (hsPDA). It is unknown if LUS scores can delineate trajectories of pulmonary edema in extremely preterm (EPT) infants.

Objective: To investigate the role of LUS scores in evaluating pulmonary edema severity in EPT infants with hsPDA. We hypothesized that pulmonary edema, a marker of severity of left to right shunt across a PDA, would be detected by serial LUS score. Secondary analysis investigated pleural line characteristics and severe bronchopulmonary dysplasia (sBPD), grade II-III BPD by Jensen criteria, diagnosis at 36 weeks.

Design/Methods: Clinically stable infants born ≤28 weeks gestation were evaluated using standard LUS scores (6-zone US, Brat et. al.) by investigators blinded to clinical data. LUS images were obtained and scored on day of life (DOL) 3 (LUS 1), DOL 6-8 (LUS 2) and DOL 10-12 (LUS 3). ECHOs (obtained at the discretion of the clinical team) were reviewed to create two distinct groups: hsPDA (size >2.0 mm, transductal peak velocity < 2.0 m/sec, LA:Ao root ratio >1.5, and absent/retrograde flow in the descending Ao) and non-hsPDA. Increased LA:Ao root ratio and/or absent or reversed end-diastolic flow was required for hsPDA. Wilcoxon rank-sum test was used to compare hsPDA by LUS scores.

Results: Analyses included 46 of 55 infants (17 with hsPDA and 29 without hsPDA). Nine infants that did not meet study criteria were excluded. Pleural line thickness data was available for 31 infants. Gestational age (p < 0.001) and birth weight (p < 0.001) were lower in the hsPDA group vs the non-hsPDA group. Nearly all infants with hsPDA had sBPD at 36 weeks (p < 0.001) (Table 1). LUS scores between hsPDA and non-hsPDA groups were significantly higher on LUS 2 (p=0.006) and LUS 3 (p < 0.001). A serial decrease in scores was observed in 2 hsPDA patients after successful pharmacologic treatment. Pleural line thickness at LUS 3 between the hsPDA group and non-hsPDA group (p=0.022) was significantly higher. No pleural line thickness differences were seen at LUS 1 or 2 (Table 2). There were no differences in pleural line regularity, fragmentation, or subpleural consolidation.

Conclusion(s): LUS score between 6-12 days has potential as an adjunctive tool, in conjunction with echocardiogram, for evaluating hsPDAs. There is an association between hsPDA and sBPD. Investigation of pleural line characteristics, including thickness, may aid in differentiating pulmonary pathologies confounded by prematurity-related lung disease.

Image 1. Consort Diagram of Study Population
Breakdown of study population. 9 infants were excluded. 46 were included, 17 with hsPDA. 31 patients were available for secondary analysis of pleural line characteristics.

Table 1. Clinical characteristics of Extremely Preterm Infants
Demographic information, LUS score results and BPD outcomes between hsPDA group and non-hsPDA group.

Table 2. Pleural Line Thickness of Extremely Preterm Infants
Mean pleural line measurements at LUS 1, LUS 2, LUS 3.