Functional neuroimaging of responses to multiple sensory stimulations in newborns with perinatal asphyxia.

Background: Functional neuroimaging can provide pathophysiological information in perinatal asphyxia (PA). However, fundamental unresolved questions remain related to the influence of neurovascular coupling (NVC) maturation on functional responses in early development. We aimed to probe the feasibility and compare the responses to multiple sensory stimulations in newborns with PA using functional magnetic resonance imaging (fMRI) and functional near-infrared spectroscopy (fNIRS). Methods: Responses to visual, auditory, and sensorimotor passive stimulation were measured with fMRI and fNIRS and compared in 18 term newborns with PA and six controls. Results: Most newborns exhibited a positive fMRI response during visual and sensorimotor stimulation, higher in the sensorimotor. An asymmetric pattern (negative in the left hemisphere) was observed in auditory stimulation. The fNIRS response most resembling the adult pattern (positive) in PA occurred during auditory stimulation, in which oxyhemoglobin (HbO) increased, and deoxyhemoglobin (HbR) decreased. Significative differences were found in the HbO and HbR profiles in newborns with PA compared to the controls, more evident in auditory stimulation. Positive correlations between the fMRI BOLD signal and at least one fNIRS channel (HbO) in all stimuli in newborns with PA were identified: the strongest was in the auditory (r=0.704) and the weakest in the sensorimotor (r=0.544); in more fNIRS channels, in the visual. Conclusions: Both techniques are feasible physiological assessment tools, suggesting a distinctive level of maturation in sensory and motor areas. Differences in fNIRS profiles in newborns with PA and controls and the fMRI-fNIRS relationship observed can encourage the fNIRS as a clinically emergent valuable tool.

The role of early functional neuroimaging in predicting neurodevelopmental outcomes in neonatal encephalopathy.

Reliably assessing the early neurodevelopmental outcomes in infants with neonatal encephalopathy (NE) is of utmost importance to advise parents and implement early and personalized interventions. We aimed to evaluate the accuracy of neuroimaging modalities, including functional magnetic resonance imaging (fMRI) in predicting neurodevelopmental outcomes in NE. Eighteen newborns with NE due to presumed perinatal asphyxia (PA) were included in the study, 16 of whom underwent therapeutic hypothermia. Structural magnetic resonance imaging (MRI), and fMRI during passive visual, auditory, and sensorimotor stimulation were acquired between the 10th and 14th day of age. Clinical follow-up protocol included visual and auditory evoked potentials and a detailed neurodevelopmental evaluation at 12 and 18 months of age. Infants were divided according to sensory and neurodevelopmental outcome: severe, moderate disability, or normal. Structural MRI findings were the best predictor of severe disability with an AUC close to 1.0. There were no good predictors to discriminate between moderate disability versus normal outcome. Nevertheless, structural MRI measures showed a significant correlation with the scores of neurodevelopmental assessments. During sensorimotor stimulation, the fMRI signal in the right hemisphere had an AUC of 0.9 to predict absence of cerebral palsy (CP). fMRI measures during auditory and visual stimulation did not predict sensorineural hearing loss or cerebral visual impairment. CONCLUSION: In addition to structural MRI, fMRI with sensorimotor stimulation may open the gate to improve the knowledge of neurodevelopmental/motor prognosis if proven in a larger cohort of newborns with NE. WHAT IS KNOWN: • Establishing an early, accurate neurodevelopmental prognosis in neonatal encephalopathy remains challenging. • Although structural MRI has a central role in neonatal encephalopathy, advanced MRI modalities are gradually being explored to optimize neurodevelopmental outcome knowledge. WHAT IS NEW: • Newborns who later developed cerebral palsy had a trend towards lower fMRI measures in the right sensorimotor area during sensorimotor stimulation. • These preliminary fMRI results may improve future early delineation of motor prognosis in neonatal encephalopathy.

Secondary Hepatic Injury in Pediatric Intensive Care: Risk Factors and Prognostic Impact.

OBJECTIVES: The aim of this study was to assess the profile of secondary hepatic injury (SHI), to determine risk factors and to evaluate its impact on prognosis of pediatric intensive care patients. METHODS: An exploratory observational and retrospective study was conducted in a Pediatric Intensive Care Unit. Two groups were defined: with SHI [alanine aminotransferase (ALT) ≥100 IU/L or gamma glutamyl transpeptidase (GGT)≥100 IU/L or direct bilirubin ≥30 µmol/L] and without. SHI was divided into 3 patterns: cytolysis, cholestasis, and mixed. RESULTS: SHI occurred in 16.5%, cytolysis in 5%, cholestasis in 4%, and mixed pattern in 7%. Independent risk factors for SHI were: organ dysfunction score PELOD-2 in D1 in cytolysis (n = 28); total parenteral nutrition and Pediatric Index of Mortality 3 (PIM3) in cholestasis (n = 23); sepsis, oncologic comorbidities, PIM3, and respiratory dysfunction in mixed pattern (n = 37). The ALT was an independent risk factor and a good predictor of mortality (AUC = 0.865) with a cut-off of 137 IU/L. CONCLUSIONS: SHI was associated with worst prognostic. ALT may be useful for detecting patients at increased risk of death, probably being a surrogate marker of the illness severity, reflecting a secondary injury.