(14) Cerebral Tissue Oxygenation in the First Week Among Preterm Neonates Is Associated with the General Movements Assessment

Amy C. Rothwell, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States; Matthew Harer, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States; Claudette O. Adegboro, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States

Background: Preterm infants are at high risk for brain injury, which can lead to a diagnosis of cerebral palsy (CP) in childhood. The general movements assessment (GMA) is a validated screening tool with high predictability of CP used to evaluate former preterm infants prior to neonatal intensive care unit (NICU) discharge. Monitoring cerebral tissue oxygenation (CrSO₂) with near-infrared spectroscopy (NIRS) is increasingly used in the NICU to detect cerebral hypoxia and potentially reduce the risk of future neurodevelopmental abnormalities like CP. No prior studies among preterm infants have evaluated the relationship between CrSO₂ values and the GMA.

Objectives: To determine the relationship between CrSO₂ and GMA among preterm infants at NICU discharge.

Design/Methods: A secondary retrospective analysis of a prospective NIRS study was performed. INVOS NIRS sensors were placed on neonates < 32 weeks within 48 hours of age. Continuous, every 5-second CrSO₂ data was collected until 7 days of age. Means were calculated in 12-hour epochs from 48 hours to 168 hours of age. GMA results, classified as normal (writhing) or abnormal (poor repertoire) (Figure 1), and head ultrasound (HUS) findings identified prior to NICU discharge were included.

Results: GMA was performed prior to NICU discharge for 19 of 35 neonates, with mean gestational age of 29.2 ± 2.4 weeks and mean birth weight of 1315 ± 399 g. Mean time of GMA was 35.7 ± 1.2 weeks post menstrual age, with 10 scoring normal writhing and 9 with poor repertoire. Average continuous CrSO₂ was significantly lower in infants demonstrating poor repertoire on GMA compared to those with normal writhing (75.14 vs. 83.81, p< 0.05, Figure 2). This significance was appreciated in 12-hour intervals starting at 48, 72, 84, 96, 108, and 120 hours (Figure 3). No significant differences in CrSO₂ were seen when GMA subgroups were further divided by HUS results (Figure 4).

Conclusion: In this pilot study, preterm infants with poor repertoire on GMA demonstrated significantly lower CrSO₂ values in the first week of age, specifically from 48 to 132 hours. This preliminary analysis suggests that CrSO₂ values in the first week may be used as a surrogate measure for future CP diagnoses. Further investigation is needed to characterize differences in CrSO₂ associated with GMA in preterm infants, and to evaluate the relationship between early cerebral oxygenation, GMA, and long-term neurodevelopmental outcomes.