Oral or Poster Presentation
Concurrent Session 3D - Neo Neurosciences & Neuro Critical Care
Introduction: Majority of preterm infants are born between 29 to 36 weeks’ gestational age (GA) at a time when the brain undergoes several developmental changes. Non-invasive cerebral monitoring could allow the early identification of preterm infants who present with atypical brain development and requiring closer developmental follow-up. We postulate that measures of brain hemodynamics and metabolism using Frequency Domain Near Infra-red and Diffuse Correlation Spectroscopic (FDNIRS-DCS) technologies are valid biomarkers of cerebral maturation in preterm infants.
Methods: We consecutively recruited 100 preterm infants born 29-36 weeks’ GA in a level-3 neonatal intensive care unit. We used FDNIRS-DCS to longitudinally monitor cerebral oxygen saturation (SO2), oxygen extraction fraction (OEF), cerebral blood flow index (CBFi) and cerebral metabolic rate of oxygen consumption index (CMRO2i) from one week to term-equivalent age. Pearson correlation analyses were performed to assess the relationship between FDNIRS-DCS measures and infant age. We further examined the rate of change in these cerebral parameters per gestational age groups.
Results: Mean GA was 33.4±1.9 weeks, mean birth weight 1890±583 grams, and 54% were male. We obtained a median of 2 (range 1-7) FDNIRS-DCS measures per patient for a total of 264 measures for the entire cohort. Figure 1 shows that CMRO2i (R=0.209, p<0.05, n=132) and CBFi (R=0.524, p<0.001, n=206) increased with postmenstrual age while no significant change was observed in OEF (R = -0.052, p = 0.404, n=264) and SO2 (R=0.093, p=0.13, n = 264). Only CBFi increased with chronological age (R=0.573, p<0.001, n=206). The rate of the increase in CBFi was associated with increasing GA, although not statistically significant.
Conclusion: CMRO2i and CBFi increased with increasing postmenstrual age, suggesting that these measures reflect brain growth and maturation. Whether these cerebral biomarkers correlate with neurodevelopmental outcomes remain to be studied.