Abnormal heart rate variability at school age in survivors of neonatal hypoxic-ischemic encephalopathy managed with therapeutic hypothermia.

BACKGROUND AND OBJECTIVE: Major deficits in the autonomic nervous system function, detected by measuring heart rate variability (HRV), are reported in neonatal hypoxic-ischemic encephalopathy (HIE)). However, it is unknown if they will recover in the long-term. Because of the possible implications for the neurological outcome, this study aimed to evaluate the HRV at school age, in a cohort of children who survived HIE managed with therapeutic hypothermia. METHODS: A cross-sectional study of HRV in 40 children: 20 HIE survivors and 20 healthy peers. All underwent 5-min plethysmography using the PPG Stress Flow device (BioTekna Italy). Absolute and normalized HRV spectral power in the very low frequency (VLF), low frequency (LF), and high frequency (HF) bands and total power were compared between patients and healthy children. The outcome evaluation included neurological, cognitive (WISC-IV), and psychosocial (Parent Stress Index-Short Form-PSI-SF and psychosocial interview) measures. RESULTS: All mean HRV values were significantly higher in survivors of HIE, compared to healthy peers, with the larger effect size for the HF band (Total Power 8.57 ± 0.59 vs 7.82 ± 0.77 ms2, p .003 ES 0.21; HF 7.82 + 0.77 vs 8.57 + 0.59 ms2, p .001 EF 0.24). None of the children had major health, neurological and psychosocial (PSI-SF/interview) problems. The IQ (WISC-IV) was normal in 17/20 patients, borderline in 2, and <70 in 1. CONCLUSIONS: HRV measures highlight autonomic dysfunction at school age in survivors of neonatal HIE, in the absence of major neurodevelopmental and psychosocial problems. The significance of this finding for children's future life needs further neuropsychiatric investigations and longer follow-up.

Perinatal carotid artery ischemic stroke: Report of two cases.

The mechanisms of perinatal stroke are poorly understood but preclinical studies point to the crucial role of perinatal inflammation. Carotid artery occlusion represents a very rare and severe cause of perinatal stroke. We describe two cases diagnosed with extensive ischemic stroke due to carotid artery occlusion. In both cases, we demonstrated placental vasculopathy. High levels of C-reactive protein in mother and/or neonates suggested inflammatory mechanism as a potential trigger. Both cases underwent hypothermic treatment without complications because of initial diagnosis of perinatal asphyxia. The prognosis at the time of the last follow up was severe including cerebral palsy, epilepsy and cognitive impairment. Our cases contribute to the actual debate on pathogenic mechanisms and treatment options for this rare condition.

Power spectral analysis of two-channel EEG in very premature infants undergoing heat loss prevention.

OBJECTIVE: To evaluate whether wearing a wool cap, a routine practice used to prevent heat loss in premature infants, affects interpretation of electroencephalogram spectral analysis. METHODS: Eighteen premature infants (median gestational age 28 weeks, range 23-32) without neurological complications were randomized to two channel (C3, C4 referred to Cz) digital electroencephalogram recordings with (90 min) and without (90 min) wearing wool cap, at 4 days of life. Electroencephalogram was analyzed automatically by measurement of burst suppression ratio and asymmetry index and by Fast Fourier Transform to calculate total absolute spectral power; relative spectral power in the δ (0.5-3.5 Hz), θ (4-7.5 Hz), α (8-12.5 Hz), and ß (13-30 Hz) frequency bands; spectral edge frequency; and mean dominant frequency. RESULTS: The use of wool cap had no effect on all electroencephalogram parameters considered. Gestational age showed an effect on relative spectral power of all considered bands, spectral edge frequency and mean dominant frequency, while no effect was seen on burst suppression ratio and asymmetry index. Neonates born at gestational weeks lower than 28 had significantly higher relative power in the δ band and lower relative power in the α and ß bands. CONCLUSIONS: Heat loss prevention using wool cap does not affect interpretation of spectral electroencephalogram. Spectral values in our group of very premature infants without neurological complications correspond to normal data reported in the literature. Maturation changes consist of reduction of relative power of the δ band, spectral edge frequency and mean dominant frequency.

Failure of hearing screening in high-risk neonates does not increase parental anxiety.

OBJECTIVE: The aim of this study was to determine whether a failure of neonatal hearing screening affected the anxiety level of parents of high-risk infants. METHODS: Two hundred and eighty-eight parents of infants included in the neonatal hearing screening protocol of our Institution were tested with the Spielberger State-Trait Anxiety Inventory and with an open-question questionnaire investigating parents' attitude to hearing problems in their child, done at the time of audiological follow-up. 105 were parents of high-risk infants who had been discharged from neonatal intensive care unit (NICU) and 183 of low-risk infants discharged from well-baby nursery. RESULTS: No differences in anxiety levels were seen between parents of high-risk infants passing and failing neonatal hearing screening using homogeneous case-control pairs. Additionally, no differences in the level of anxiety were found between parents of high- and low-risk infants failing neonatal auditory screening. CONCLUSIONS: Failure of neonatal auditory screening does not affect the anxiety levels of parents of high-risk infants at post discharge from NICU. This finding is a key factor to be considered when evaluating the costs and benefits of tests for universal neonatal hearing screening.