401 - Cerebral Oxygenation During Infant Daily Activities in the Neonatal Intensive care Unit

Poster Number: 401
Publication Number: 401.135

santina zanelli, University of Virginia Children's Hospital, Charlottesville, VA, United States; Lisa Letzkus, University of Virginia School of Medicine, Charlottesville, VA, United States; Adrienne Doebrich, University of Virginia School of Medicine, Charlottesville, VA, United States; Michael Spaeder, University of Virginia School of Medicine, Charlottesville, VA, United States

Background: Near-Infrared Spectroscopy (NIRS) allows for the non-invasive and continuous monitoring of cerebral oxygenation (crSO2). Interventions based on crSO2 data have been shown to decrease the burden of certebral hypoxia and hyperoxia in preterm infants. However, the impact of routine neonatal intensive care unit (NICU) care on crSO2 is not fully understood. This application of NIRS monitoring will help address this gap in knowledge by providing objective data on the impact of specific daily care activities on crSO2.

Objective: To evaluate changes in crSO2 and crSO2 variability in response to routine care activities in the NICU using NIRS.

Design/Methods: Pilot observational study of clinically stable preterm infants undergoing crSO2 monitoring. Values of crSO2 were continuously captured using the ForeSight cerebral oximeter and averaged over 1-min intervals. Variability of crSO2 was calculated using the root mean of successive squared differences (RMSSD) of averaged 1-min crSO2 values over the monitoring period. To characterize changes in crSO2 variability over time, we also calculated a 60-min moving variability measure for each minute of monitoring using the RMSSD differences from the previous 60 minutes. No changes in NICU care were made based on NIRS. All patient care activities and therapies during this observational period were logged by the primary care team. Additional clinical and demographic data was obtained via chart review. Analyses for this study focused on activities provided by parents as well as therapy sessions.

Results: 12 infants were included in the study (gestational age 27.5 ± 4.8; birthweight 1204 ± 817 grams, 25% male). NIRS monitoring occurred at a mean postmentrual age of 36.2 ± 5 weeks. Infants were monitored for a median duration of 47 hours (IQR 27-48 hours). The median duration of parental activities and therapies during the period of monitoring was 3.5 hours (IQR 1 - 7 hours). During parental activities and therapies, we observed both an increase in crSO2 (77% to 79%, p=0.04) and a 14% increase in crSO2 variability (p=0.04).Conclusion(s): We observed an increase in both crSO2 and crSO2 variability in NICU patients during parental activities and therapies. We hypothesize that these changes represent an increase in cerebral oxygen delivery during these periods of activity. Further study is needed to investigate this association in a larger cohort of patients as well as well as the relationship with neurodevelopmental outcomes.