P1.197: Comparison of Multi-Organ Dysfunction in Term and Preterm Neonates with Hypoxic-Ischemic Encephalopathy

Background: Hypoxic-ischemic encephalopathy (HIE) is a complex condition resulting from oxygen deprivation at birth. As the body redirects cardiac output to protect the brain, this can lead to multi-organ dysfunction (MOD). While prior research has primarily focused on term neonates with moderate to severe HIE, data on MOD in preterm HIE neonates remain limited. The objectives of this study are to compare the incidence of HIE in term and preterm neonates and to evaluate the severity of MOD, as well as electroencephalographic (EEG) and magnetic resonance imaging (MRI) abnormalities, in both term and preterm HIE neonates.

Methods: This retrospective cohort study included term and preterm neonates diagnosed with HIE at Parkland Hospital between 2009 and 2023. Sarnat staging classified neonates into mild and moderate/severe HIE. MOD was assessed using cardiac, renal, and hepatic markers, including troponin levels, echocardiography, creatinine, urine output, and liver function tests. EEG and MRI findings were analyzed to determine neurological outcomes.

Results: Term and preterm neonates had a similar incidence of HIE, with rates of 0.4 per 1,000 live births in both groups. Among 452 term HIE neonates, 57% had liver injury, 55% had cardiac injury, and 44% had renal dysfunction. Among 54 preterm HIE neonates, 67% had liver injury, 55% cardiac dysfunction, and 37% renal impairment. The prevalence and severity of MOD in preterm HIE neonates were higher and more significant than those observed in term neonates (p = 0.041). Additionally, preterm neonates exhibited higher rates of electrographic seizures (35%), discontinuous EEG background activity (68%), and MRI/MRS abnormalities (83%). Beyond the basal ganglia and watershed injury observed in term infants, a significant proportion of preterm infants showed evidence of other injuries, as highlighted in Table 2. Mortality was also higher in preterm neonates (18% vs. 9% in term neonates).

Conclusion: MOD is a significant complication of HIE in both term and preterm neonates, with a greater incidence and severity in preterm infants. These findings highlight the need for tailored screening and management strategies for MOD in this high-risk population. Future neuroprotective approaches should account for the increased vulnerability of preterm neonates to systemic injury.