P1.214: Effects of PDA Treatment Timing in VLBW Infants

Background: Patent Ductus Arteriosus (PDA) in preterm neonates is associated with several negative outcomes. However, management remains controversial. Studies suggest targeted PDA therapy may improve outcomes, but optimal timing remains unclear. Our objective is to evaluate the effect of pharmacotherapy timing on short-term outcomes. We hypothesize PDA closure beyond 10 days of age in VLBW infants is associated with increased risk of death or moderate-severe BPD.

Methods: VLBW neonates born 2017-2019 and admitted to a single Level III NICU were identified for this retrospective study. Patients were excluded if they died prior to 7 days. Clinical data were extracted from the medical records. Respiratory status before and after treatment was compared with the respiratory severity score (RSS) (product of mean airway pressure and FiO2). Patients with spontaneous closure were used as controls; treated infants were grouped into closure by 10 days and closure after 10 days of age. Pharmacotherapy was at the discretion of the clinician. Groups were compared using the Chi-squared test or the Kruskal–Wallis test. Logistic regression was used to test outcomes of each treatment group compared to controls, adjusted for gestational age.

Results: 171 infants were included with median gestational age 25.7 weeks (IQR 24.4, 26.9). 88 (51%) had spontaneous closure. Among 83 treated infants, 27 (16%) were closed by 10 days and 56 (33%) were closed after 10 days (Table). 38 (46%) treated patients had the PDA closed with a single course of pharmacotherapy, 45 (54%) were treated with multiple courses of treatment.

Patients treated for PDA had higher rates of death or moderate-severe BPD (79 vs 50%, p< 0.0001) and moderate-severe BPD (74 vs 44%, p< 0.0001). Adjusted for gestational age, successful PDA treatment by 10 days did not increase the risk of death/BPD [aOR 1.4 (95% CI 0.47-4.2), p=0.54]. Closure of the PDA after 10 days was associated with increased risk of death/BPD [aOR 1.7 (95% CI 1.1-2.6), p=0.018] and moderate-severe BPD [OR 1.7 (95% CI 1.2-2.6), p=0.008].

With successful pharmacotherapy, there was no significant change in RSS [2.6 (IQR 2, 3.9) vs 2.7 (2.3, 4), p=0.23]. For unsuccessful therapy, the RSS was worse after treatment [2.6 (IQR 2.1, 3.6) vs 3.6 (2.6, 4.8), p=0.0003].

Conclusion: We demonstrate closure of the PDA after 10 days of age is associated with increased risk of death/BPD and mod-severe BPD while successful pharmacotherapy with closure by 10 days of age is not. Patients who failed pharmacotherapy had higher RSS after treatment compared to before. Additional research is needed to determine if changes in respiratory status during PDA therapy are associated with neonatal outcomes.