477 - Therapeutic Hypothermia in Hypoxic-Ischemic Encephalopathy Initiated Prior to Transport in Outborn Infants: Comparison of Outcomes with Inborn Infants.

Poster Number: 477
Publication Number: 477.3019

Background: Hypoxic Ischemic Encephalopathy (HIE) is a significant cause of morbidity and mortality in the newborn infants. There is limited information on outborn neonates with HIE who received Therapeutic Hypothermia (TH) during transport.

Objective: To compare early clinical characteristics and short-term outcomes of outborn versus inborn infants with HIE who received TH.

Design/Methods: Infants (term and late preterm) with moderate to severe HIE needing TH comprised the study participants. Data on perinatal and birth history and clinical characteristics were retrospectively obtained from the medical records. Data of Magnetic Resonance Imaging (MRI) outcomes (based on NICHD MRI Severity Score) were analyzed by a blinded neuroradiologist. Baseline characteristics and outcomes were compared between infants born at referring facilities (outborn) and those inborn at out level 4 neonatal ICU. A trained neonatal transport team initiated TH within 6 hours.

Results: A total of 104 infants (73 outborn and 31 inborn) were included in this study. Clinical characteristics significantly differed between outborn and inborn infants: A higher proportion of outborn infants received chest compression compared to inborn infants (52.1% vs 3.2%), had coagulopathy (57.5% vs 29.0%), cardiac dysfunction (53.4% vs 29.0%) and/or increased need for blood product transfusions (57.5% vs 35.5%), all p< 0.05. Organ injury occurred in 74% of outborn infants and in 35.5% of inborn infants (p=0.01). All infants had TH initiated within 6 hours of life: median 5 (4 to 6) and 1 ( 1 to 3) hours for outborn and inborn infants respectively, p< 0.001. There were no statistically significant differences in MRI severity scores in outborn compared to inborn infants (p=0.12). There were no differences in feeding outcomes, length of stay, and mortality between groups (all p=NS). Discharge on antiepileptic therapy was higher in outborn (39.9%) compared to inborn (12.9%) infants, p=0.01.

Conclusion(s): Our findings suggest that outborn infants had worse clinical status initially. However, their short term outcomes by MRI imaging were no different from inborn infants who had better clinical status in the immediate neonatal period. These findings are in support of a need for early transport and prompt initiation of TH within the first 6 hours of life.