Profile of minor neurological findings after perinatal asphyxia

Quantitative EEG features during the first day correlate to clinical outcome in perinatal asphyxia

OBJECTIVE

To assess whether computational electroencephalogram (EEG) measures during the first day of life correlate to clinical outcomes in infants with perinatal asphyxia with or without hypoxic-ischemic encephalopathy (HIE).

METHODS

We analyzed four-channel EEG monitoring data from 91 newborn infants after perinatal asphyxia. Altogether 42 automatically computed amplitude- and synchrony-related EEG features were extracted as 2-hourly average at very early (6 h) and early (24 h) postnatal age; they were correlated to the severity of HIE in all infants, and to four clinical outcomes available in a subcohort of 40 newborns: time to full oral feeding (nasogastric tube NGT), neonatal brain MRI, Hammersmith Infant Neurological Examination (HINE) at three months, and Griffiths Scales at two years.

RESULTS

At 6 h, altogether 14 (33%) EEG features correlated significantly to the HIE grade ([r]= 0.39-0.61, p < 0.05), and one feature correlated to NGT ([r]= 0.50). At 24 h, altogether 13 (31%) EEG features correlated significantly to the HIE grade ([r]= 0.39-0.56), six features correlated to NGT ([r]= 0.36-0.49) and HINE ([r]= 0.39-0.61), while no features correlated to MRI or Griffiths Scales.

CONCLUSIONS

Our results show that the automatically computed measures of early cortical activity may provide outcome biomarkers for clinical and research purposes.

IMPACT

The early EEG background and its recovery after perinatal asphyxia reflect initial severity of encephalopathy and its clinical recovery, respectively. Computational EEG features from the early hours of life show robust correlations to HIE grades and to early clinical outcomes. Computational EEG features may have potential to be used as cortical activity biomarkers in early hours after perinatal asphyxia.

Neurological examination of healthy term infants at ages 6 and 10 weeks in Tshwane District

Background

Globally, there is a significant gap in detailed neurodevelopmental data for infants under 3 months, despite 6 weeks being identified a critical milestone for neuro-behavioural development. Normative values and optimal scores for healthy infants at 6 and 10 weeks postnatally are lacking in many settings. In South Africa, the statutory neurodevelopmental assessments at these ages exclude notable characteristics of central nervous system maturation and limit opportunities to collect data of early developmental progress.

Objectives

Our study aimed to assess developmental characteristics of healthy term infants aged 6 and 10 weeks using the Hammersmith Neonatal Neurological Examination (HNNE).

Method

A prospective longitudinal study was performed on 35 healthy term-born infants from low-risk pregnancies at 6 and 10 weeks' postnatal age in the Tshwane district. The statuses of infants' neurodevelopment in six domains were recorded using the HNNE. Optimality scores were derived from the raw scores of 34 items, using the 10th and 5th percentiles as cut-off points.

Results

Evidences of neurodevelopmental advancements, particularly in posture, muscle tone and visual behaviour between 6 and 10 weeks were illustrated, and total examination optimality scores of 29.5 in 91% and 31.5 in 94% of infants were recorded at 6 and 10 weeks, respectively.

Conclusion

This article provides data on the neurodevelopment characteristics of infants at and between 6- and 10-weeks post term ages.

Clinical Implications

The findings support the viewpoint to identify important milestone characteristics during early screening.

Networks of cortical activity show graded responses to perinatal asphyxia

BACKGROUND

Perinatal asphyxia often leads to hypoxic-ischemic encephalopathy (HIE) with a high risk of neurodevelopmental consequences. While moderate and severe HIE link to high morbidity, less is known about brain effects of perinatal asphyxia with no or only mild HIE. Here, we test the hypothesis that cortical activity networks in the newborn infants show a dose-response to asphyxia.

METHODS

We performed EEG recordings for infants with perinatal asphyxia/HIE of varying severity (n = 52) and controls (n = 53) and examined well-established computational metrics of cortical network activity.

RESULTS

We found graded alterations in cortical activity networks according to severity of asphyxia/HIE. Furthermore, our findings correlated with early clinical recovery measured by the time to attain full oral feeding.

CONCLUSION

We show that both local and large-scale correlated cortical activity are affected by increasing severity of HIE after perinatal asphyxia, suggesting that HIE and perinatal asphyxia are better represented as a continuum rather than the currently used discreet categories. These findings imply that automated computational measures of cortical function may be useful in characterizing the dose effects of adversity in the neonatal brain; such metrics hold promise for benchmarking clinical trials via patient stratification or as early outcome measures.

IMPACT

Perinatal asphyxia causes every fourth neonatal death worldwide and provides a diagnostic and prognostic challenge for the clinician. We report that infants with perinatal asphyxia show specific graded responses in cortical networks according to severity of asphyxia and ensuing hypoxic-ischaemic encephalopathy. Early EEG recording and automated computational measures of brain function have potential to help in clinical evaluation of infants with perinatal asphyxia.

Ultrasound Diagnosis and Near-Infrared Spectroscopy in the Study of Encephalopathy in Neonates Born under Asphyxia: Narrative Review

Brain injury resulting from adverse events during pregnancy and delivery is the leading cause of neonatal morbidity and disability. Surviving neonates often suffer long-term motor, sensory, and cognitive impairments. Birth asphyxia is among the most common causes of neonatal encephalopathy. The integration of ultrasound, including Doppler ultrasound, and near-infrared spectroscopy (NIRS) offers a promising approach to understanding the pathology and diagnosis of encephalopathy in this special patient population. Ultrasound diagnosis can be very helpful for the assessment of structural abnormalities associated with neonatal encephalopathy such as alterations in brain structures (intraventricular hemorrhage, infarcts, hydrocephalus, white matter injury) and evaluation of morphologic changes. Doppler sonography is the most valuable method as it provides information about blood flow patterns and outcome prediction. NIRS provides valuable insight into the functional aspects of brain activity by measuring tissue oxygenation and blood flow. The combination of ultrasonography and NIRS may produce complementary information on structural and functional aspects of the brain. This review summarizes the current state of research, discusses advantages and limitations, and explores future directions to improve applicability and efficacy.

Risk Factors for Birth Asphyxia in Hospital-Delivered Newborns in Dodoma, Tanzania: A Case-Control Study

Introduction

Asphyxia at birth remains the leading cause of neonatal morbidity and mortality worldwide, accounting for ∼23% of all neonatal deaths. Although the causes vary from country to country, early identification and treatment of risk factors can improve the situation.

Objectives

To determine the risk factors of birth asphyxia in hospital-delivered neonates in Dodoma, Tanzania.

Methods

A matched case-control study was conducted from May to July 2017 at Dodoma Region Referral Hospital. Data were collected using a semistructured questionnaire and a standard antenatal care index card. Cases were neonates diagnosed with asphyxia at birth ( N  =  100), while controls were neonates not diagnosed with asphyxia at birth ( N  =  300). A binary logistic regression model was used to assess the independent variables associated with birth asphyxia and reported as crude and adjusted odds ratios along with their 95% confidence intervals.

Results

A total of 400 newborns and their birth mothers were involved in the study. The average age of the case mothers was 26.9 years ( SD  =  7.85) and that of the control mothers was 27.24 years ( SD  =  6.08). Place of residence, anemia, maternal age, prenatal visits attended, use of herbs during labor, previously complicated pregnancy, duration of labor, meconium-stained amniotic fluid, and mode of delivery were predictors of birth asphyxia.

Conclusion

The study showed that most predictors of birth asphyxia can be prevented. The results suggest appropriate health education before conception, effective follow-up through prenatal care, early identification and treatment of high-risk pregnant women, and proper monitoring of labor and delivery.

Risk Factors for Birth Asphyxia in Hospital-Delivered Newborns in Dodoma, Tanzania: A Case-Control Study

Introduction

Asphyxia at birth remains the leading cause of neonatal morbidity and mortality worldwide, accounting for ∼23% of all neonatal deaths. Although the causes vary from country to country, early identification and treatment of risk factors can improve the situation.

Objectives

To determine the risk factors of birth asphyxia in hospital-delivered neonates in Dodoma, Tanzania.

Methods

A matched case-control study was conducted from May to July 2017 at Dodoma Region Referral Hospital. Data were collected using a semistructured questionnaire and a standard antenatal care index card. Cases were neonates diagnosed with asphyxia at birth (N  =  100), while controls were neonates not diagnosed with asphyxia at birth (N  =  300). A binary logistic regression model was used to assess the independent variables associated with birth asphyxia and reported as crude and adjusted odds ratios along with their 95% confidence intervals.

Results

A total of 400 newborns and their birth mothers were involved in the study. The average age of the case mothers was 26.9 years (SD  =  7.85) and that of the control mothers was 27.24 years (SD  =  6.08). Place of residence, anemia, maternal age, prenatal visits attended, use of herbs during labor, previously complicated pregnancy, duration of labor, meconium-stained amniotic fluid, and mode of delivery were predictors of birth asphyxia.

Conclusion

The study showed that most predictors of birth asphyxia can be prevented. The results suggest appropriate health education before conception, effective follow-up through prenatal care, early identification and treatment of high-risk pregnant women, and proper monitoring of labor and delivery.

Short-term neurological injury in newborns infants with overcooling in passive hypothermia and transferred to reference hospital in Colombia

AIM

The aim of the study was to determine whether overcooling (temperature <33°C) during passive hypothermia when transporting neonates with perinatal asphyxia increased the risk of short-term neurological injury.

METHODS

A retrospective observational study was performed. Newborns transferred to the LaCardio neonatal unit between January 2021 and April 2022 with moderate and severe perinatal asphyxia and who received passive hypothermia during transport were included. A temperature of <33°C was considered overcooling. A composite outcome of neurological injury was defined by the presence of abnormalities on brain magnetic resonance imaging, video telemetry, seizure before discharge or both.

RESULTS

The study included 101 newborns. A total of 18 neonates had a temperature <33°C after transportation. Neurological injuries were present in 21.8% of the temperature <33°C group and 78.2% of the temperature ≥33°C group. Temperature <33°C at the end of transport (aOR 9.2, 95% CI 1.1-77.3) were associated with neurological injury before discharge from the unit.

CONCLUSION

During transportation, overcooling in neonates with asphyxia increases the risk of neurological injury before discharge from the neonatal unit. It is important to qualify the transport team with adequate training and equipment for therapeutic hypothermia.

A comparative study of CTG monitoring one hour before labor in infants born with and without asphyxia

BACKGROUND AND AIM

Asphyxia is a condition arising when the infant is deprived of oxygen, causing Fetal brain damage or death, which is associated with hypoxia and hypercapnia. Although fetal Cardiotocography (CTG) can show the Fetal health status during labor, some studies have reported cases of fetal asphyxia despite reassuring CTGs. This study hence aimed to compare FHR Monitoring and uterine contractions in the last hour before delivered between two groups of infants born with and without asphyxia.

METHODOLOGY

The study was conducted on 70 pregnant women who delivered Taleghani and Al-Zahra academic teaching hospitals of Tabriz for labor in 2020-2021.

RESULTS

The study data showed no significant difference between mothers of infants with and without asphyxia in terms of demographics (p > 0.05). The prevalence of asphyxia was significantly higher only in mothers with the gravidity of 3 and 4 (p = 0.003). In terms of the methods for labor induction, the use of oxytocin was more common among mothers of infants with asphyxia (74.3%) than in those of infants without asphyxia (p = 0.015). The results also revealed a significant difference between infants with and without asphyxia in the Apgar score (first, fifth, and tenth minutes), need for neonatal resuscitation, umbilical cord artery Acidosis (pH, bicarbonate, and BE), and severity of HIE between two groups of infants with asphyxia and without asphyxia (p < 0.0001). The comparison of fetal CTG 0 to 20 min before the delivery indicated that normal variability was observed in 71.4% of infants born with asphyxia, whereas this figure for infants born without asphyxia was 91.4% (p = 0.031). However, the results showed no significant difference between the two groups of infants in any of the tstudied indicators at 20 and 40 min before the labor(p > 0.05). There was a significant difference between the two groups of infants in terms of deceleration at 40 and 60 min before the labor, as it was observed in 53.6% of infants born with asphyxia and only 11.1% of those born without asphyxia. The results also demonstrated a significant difference between the two groups in the type of deceleration (p = 0.025). Pearson and Spearman correlation coefficients showed a significant and direct relationship between interpretation the CTG of the three Perinatologists(p < 0.0001, r > 0.8).

CONCLUSION

The study results demonstrated a significant difference between infants born with asphyxia and those born without asphyxia in variability at 0 to 20 min before the labor and deceleration at 40 to 60 min before the labor.

Neonatal cortical activity organizes into transient network states that are affected by vigilance states and brain injury

Early neurodevelopment is critically dependent on the structure and dynamics of spontaneous neuronal activity; however, the natural organization of newborn cortical networks is poorly understood. Recent adult studies suggest that spontaneous cortical activity exhibits discrete network states with physiological correlates. Here, we studied newborn cortical activity during sleep using hidden Markov modeling to determine the presence of such discrete neonatal cortical states (NCS) in 107 newborn infants, with 47 of them presenting with a perinatal brain injury. Our results show that neonatal cortical activity organizes into four discrete NCSs that are present in both cardinal sleep states of a newborn infant, active and quiet sleep, respectively. These NCSs exhibit state-specific spectral and functional network characteristics. The sleep states exhibit different NCS dynamics, with quiet sleep presenting higher fronto-temporal activity and a stronger brain-wide neuronal coupling. Brain injury was associated with prolonged lifetimes of the transient NCSs, suggesting lowered dynamics, or flexibility, in the cortical networks. Taken together, the findings suggest that spontaneously occurring transient network states are already present at birth, with significant physiological and pathological correlates; this NCS analysis framework can be fully automatized, and it holds promise for offering an objective, global level measure of early brain function for benchmarking neurodevelopmental or clinical research.

Cortical networks show characteristic recruitment patterns after somatosensory stimulation by pneumatically evoked repetitive hand movements in newborn infants

Controlled assessment of functional cortical networks is an unmet need in the clinical research of noncooperative subjects, such as infants. We developed an automated, pneumatic stimulation method to actuate naturalistic movements of an infant’s hand, as well as an analysis pipeline for assessing the elicited electroencephalography (EEG) responses and related cortical networks. Twenty newborn infants with perinatal asphyxia were recruited, including 7 with mild-to-moderate hypoxic–ischemic encephalopathy (HIE). Statistically significant corticokinematic coherence (CKC) was observed between repetitive hand movements and EEG in all infants, peaking near the contralateral sensorimotor cortex. CKC was robust to common sources of recording artifacts and to changes in vigilance state. A wide recruitment of cortical networks was observed with directed phase transfer entropy, also including areas ipsilateral to the stimulation. The extent of such recruited cortical networks was quantified using a novel metric, Spreading Index, which showed a decrease in 4 (57%) of the infants with HIE. CKC measurement is noninvasive and easy to perform, even in noncooperative subjects. The stimulation and analysis pipeline can be fully automated, including the statistical evaluation of the cortical responses. Therefore, the CKC paradigm holds great promise as a scientific and clinical tool for controlled assessment of functional cortical networks.