Skip to main content
2025 AAP National Conference and Exhibition Main banner
 
Session Icons
Closed Captioning
Closed Captioning
Livestream
Livestream
Presentado en Espanol
Presentado en Espanol
Sold Out Ticketed Session
Sold Out Ticketed Session
Special Event
Special Event
Ticketed Session
Ticketed Session
Traduccion Espanol
Traduccion Espanol
Poster Icons
Oral Presentation
Oral Presentation
Poster Presentation
Poster Presentation

Original Research

Program: Section on Neonatal-Perinatal Medicine

P1.180: Therapeutic hypothermia in 35-36 week preterm infants with encephalopathy: The US National Database

Friday, September 26, 2025
6:00 PM - 7:00 PM MDT
Location: Colorado Convention Center, Four Seasons Ballroom 1 & 2
Poster Presentation
Background: Therapeutic hypothermia (TH) is the standard of care for hypoxic ischemic encephalopathy (HIE) among infants ≥36 weeks (wk) of gestational age (GA). The safety and efficacy for TH infant with 35 wk GA has not been established.

Objectives: To assess the clinical characteristics and outcomes in 35 wk vs 36 wk preterm infants diagnosed with HIE.

Methods: We examined the National Inpatient Sample (NIS) datasets for the years 2016-2020. All infants born with GA of 35 wk and 36 wk were included. Infants diagnosed with HIE with or without TH treatment were identified. Outcomes were compared between groups using Chi-square and Fisher Exact tests. Logistic regression analyses were used to calculate adjusted odds ratios (OR) while controlling for significant maternal, perinatal, and neonatal confounders. Cochrane Armitage test for trend was used to analyze TH utilization over the years.

Results: The study included 1,002,009 infants. In the 35 wk infants (n=358,571), 1521 (0.42%) had HIE, whereas in the 36 wk infants (n=643,338), 2520 (0.39%) had HIE. The prevalence of HIE did not differ (aOR=0.95, CI: 0.89-1.02, p< 0.17) nor the HIE-related mortality: n=174 (11.0%) vs. n=271 (10.4%), aOR=1.14 (0.82-1.41, p=0.24). TH in HIE infants was less utilized in 35 wk vs 36 wk; 306 (20%) vs 579 (23%), aOR=0.85 (CI 0.72-0.99, p=0.04). TH-associated mortality did not differ in 35 wk than 36 wk infants (5.9% vs 7.8%; aOR=0.97, CI:0.49-1.91, p=0.93). Complication associated with TH are listed in Table 1. Utilization of TH has significantly increased from 11.4% and 13.8% in 2016 to 26.1% and 25.9% in 2020 for 35 wk (Z= 3.51, p < 0.001) and 36 wk (Z= 3.33, p < 0.001) infants, respectively.

Conclusion: HIE was diagnosed at comparable rates in infants with 35 wk and 36 wk of gestation. The utilization of TH was associated with significant reduction of mortality in both GA groups. Potential adverse outcomes were comparable in both GA groups.