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1.
Sci Rep ; 14(1): 3176, 2024 02 07.
Article En | MEDLINE | ID: mdl-38326455

Hypoxic-ischemic encephalopathy (HIE) results from a lack of oxygen to the brain during the perinatal period. HIE can lead to mortality and various acute and long-term morbidities. Improved bedside monitoring methods are needed to identify biomarkers of brain health. Functional near-infrared spectroscopy (fNIRS) can assess resting-state functional connectivity (RSFC) at the bedside. We acquired resting-state fNIRS data from 21 neonates with HIE (postmenstrual age [PMA] = 39.96), in 19 neonates the scans were acquired post-therapeutic hypothermia (TH), and from 20 term-born healthy newborns (PMA = 39.93). Twelve HIE neonates also underwent resting-state functional magnetic resonance imaging (fMRI) post-TH. RSFC was calculated as correlation coefficients amongst the time courses for fNIRS and fMRI data, respectively. The fNIRS and fMRI RSFC maps were comparable. RSFC patterns were then measured with graph theory metrics and compared between HIE infants and healthy controls. HIE newborns showed significantly increased clustering coefficients, network efficiency and modularity compared to controls. Using a support vector machine algorithm, RSFC features demonstrated good performance in classifying the HIE and healthy newborns in separate groups. Our results indicate the utility of fNIRS-connectivity patterns as potential biomarkers for HIE and fNIRS as a new bedside tool for newborns with HIE.


Hypothermia, Induced , Hypoxia-Ischemia, Brain , Humans , Infant, Newborn , Infant , Hypoxia-Ischemia, Brain/diagnostic imaging , Hypoxia-Ischemia, Brain/therapy , Spectroscopy, Near-Infrared/methods , Brain/diagnostic imaging , Magnetic Resonance Imaging , Hypothermia, Induced/methods , Biomarkers
4.
Pediatr Res ; 94(5): 1797-1803, 2023 11.
Article En | MEDLINE | ID: mdl-37353661

BACKGROUND: Despite treatment with therapeutic hypothermia, hypoxic-ischemic encephalopathy (HIE) is associated with adverse developmental outcomes, suggesting the involvement of subcortical structures including the thalamus and basal ganglia, which may be vulnerable to perinatal asphyxia, particularly during the acute period. The aims were: (1) to examine subcortical macrostructure in neonates with HIE compared to age- and sex-matched healthy neonates within the first week of life; (2) to determine whether subcortical brain volumes are associated with HIE severity. METHODS: Neonates (n = 56; HIE: n = 28; Healthy newborns from the Developing Human Connectome Project: n = 28) were scanned with MRI within the first week of life. Subcortical volumes were automatically extracted from T1-weighted images. General linear models assessed between-group differences in subcortical volumes, adjusting for sex, gestational age, postmenstrual age, and total cerebral volumes. Within-group analyses evaluated the association between subcortical volumes and HIE severity. RESULTS: Neonates with HIE had smaller bilateral thalamic, basal ganglia and right hippocampal and cerebellar volumes compared to controls (all, p < 0.02). Within the HIE group, mild HIE severity was associated with smaller volumes of the left and right basal ganglia (both, p < 0.007) and the left hippocampus and thalamus (both, p < 0.04). CONCLUSIONS: Findings suggest that, despite advances in neonatal care, HIE is associated with significant alterations in subcortical brain macrostructure. IMPACT: Compared to their healthy counterparts, infants with HIE demonstrate significant alterations in subcortical brain macrostructure on MRI acquired as early as 4 days after birth. Smaller subcortical volumes impacting sensory and motor regions, including the thalamus, basal ganglia, and cerebellum, were seen in infants with HIE. Mild and moderate HIE were associated with smaller subcortical volumes.


Asphyxia Neonatorum , Hypoxia-Ischemia, Brain , Infant , Female , Pregnancy , Humans , Infant, Newborn , Hypoxia-Ischemia, Brain/diagnostic imaging , Hypoxia-Ischemia, Brain/therapy , Hypoxia-Ischemia, Brain/complications , Magnetic Resonance Imaging/methods , Brain/diagnostic imaging , Asphyxia Neonatorum/complications , Asphyxia Neonatorum/diagnostic imaging , Asphyxia Neonatorum/therapy , Basal Ganglia/diagnostic imaging
5.
Sci Rep ; 13(1): 3730, 2023 03 06.
Article En | MEDLINE | ID: mdl-36878952

Germinal Matrix-Intraventricular Hemorrhage (GMH-IVH) remains a significant cause of adverse neurodevelopment in preterm infants. Current management relies on 2-dimensional cranial ultrasound (2D cUS) ventricular measurements. Reliable biomarkers are needed to aid in the early detection of posthemorrhagic ventricular dilatation (PHVD) and subsequent neurodevelopment. In a prospective cohort study, we incorporated 3-dimensional (3D) cUS and functional near-infrared spectroscopy (fNIRS) to monitor neonates with GMH-IVH. Preterm neonates (≤ 32 weeks' gestation) were enrolled following a GMH-IVH diagnosis. Neonates underwent sequential measurements: 3D cUS images were manually segmented using in-house software, and the ventricle volumes (VV) were extracted. Multichannel fNIRS data were acquired using a high-density system, and spontaneous functional connectivity (sFC) was calculated. Of the 30 neonates enrolled in the study, 19 (63.3%) had grade I-II and 11 (36.7%) grade III-IV GMH-IVH; of these, 7 neonates (23%) underwent surgical interventions to divert cerebrospinal fluid (CSF). In infants with severe GMH-IVH, larger VV were significantly associated with decreased |sFC|. Our findings of increased VV and reduced sFC suggest that regional disruptions of ventricular size may impact the development of the underlying white matter. Hence, 3D cUS and fNIRS are promising bedside tools for monitoring the progression of GMH-IVH in preterm neonates.


Infant, Premature , Spectroscopy, Near-Infrared , Infant, Newborn , Infant , Humans , Prospective Studies , Cerebral Hemorrhage/diagnostic imaging , Heart Ventricles
6.
Sci Rep ; 12(1): 181, 2022 01 07.
Article En | MEDLINE | ID: mdl-34996949

A major concern with preterm birth is the risk of neurodevelopmental disability. Poor cerebral circulation leading to periods of hypoxia is believed to play a significant role in the etiology of preterm brain injury, with the first three days of life considered the period when the brain is most vulnerable. This study focused on monitoring cerebral perfusion and metabolism during the first 72 h after birth in preterm infants weighing less than 1500 g. Brain monitoring was performed by combining hyperspectral near-infrared spectroscopy to assess oxygen saturation and the oxidation state of cytochrome c oxidase (oxCCO), with diffuse correlation spectroscopy to monitor cerebral blood flow (CBF). In seven of eight patients, oxCCO remained independent of CBF, indicating adequate oxygen delivery despite any fluctuations in cerebral hemodynamics. In the remaining infant, a significant correlation between CBF and oxCCO was found during the monitoring periods on days 1 and 3. This infant also had the lowest baseline CBF, suggesting the impact of CBF instabilities on metabolism depends on the level of blood supply to the brain. In summary, this study demonstrated for the first time how continuous perfusion and metabolic monitoring can be achieved, opening the possibility to investigate if CBF/oxCCO monitoring could help identify preterm infants at risk of brain injury.


Brain/blood supply , Brain/enzymology , Cerebrovascular Circulation , Electron Transport Complex IV/metabolism , Infant, Premature , Optical Imaging , Oxygen Consumption , Oxygen/blood , Spectroscopy, Near-Infrared , Birth Weight , Enzyme Stability , Female , Gestational Age , Humans , Infant, Newborn , Infant, Very Low Birth Weight , Male , Oxidation-Reduction , Predictive Value of Tests , Proof of Concept Study , Time Factors
7.
BMC Pediatr ; 21(1): 186, 2021 04 20.
Article En | MEDLINE | ID: mdl-33879118

BACKGROUND: HIV is a major contributor to infant mortality. A significant gap remains between the uptake of infant and maternal antiretroviral regimens and only a minority of HIV-exposed infants receives prophylaxis and safe infant feeding. Losses to follow-up of HIV-exposed infants are associated with shortcomings of facility-based PMTCT models with weak community support of linkages. Use of mobile phones offers an opportunity for improving care and promoting retention assessed by timely attendance of scheduled appointments for the mother-baby pairs and achievement of an HIV-free generation. The objective of this study was to compare self-reported adherence to infant Nevirapine (NVP) prophylaxis and retention in care assessed by timely attendance of scheduled appointments over 10 weeks in HIV exposed infants randomized to 2-weekly mobile phone calls (intervention) versus no phone calls (control). METHODS: In this open label randomized controlled study, one hundred and fifty HIV infected women drawn from 3 health facilities in Western Kenya and their infants were randomly assigned to receive either phone-based reminders on PMTCT messages or standard health care messages (no calls) within 24 h of delivery. Women in the intervention arm continued to receive fortnightly phone calls. At 6- and 10-weeks following randomization we collected data on infant adherence to Nevirapine, mode of infant feeding, early HIV testing and retention in care in both study arms. All analyses were intention to treat. RESULTS: At 6 weeks follow-up, 90.7% (n = 68) of participants receiving phone calls reported adherence to infant NVP prophylaxis, compared with 72% (n = 54) of participants in the control group (p = 0.005). Participants in the intervention arm were also significantly more likely to remain in care than participants in the control group [78.7% (n = 59) vs. 58.7% (n = 44), p = 0.009 at 6 weeks and 69.3% (n = 52) vs. 37.3% (n = 28), p < 0.001 at 10 weeks]. CONCLUSIONS: These results suggest that phone calls are potentially an important tool to improve adherence to infant NVP prophylaxis and retention in care for HIV-exposed infants. TRIAL REGISTRATION: PACTR202007654729602. Registered 6 June 2018 - Retrospectively registered, https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=3449.


Anti-HIV Agents , Cell Phone Use , HIV Infections , Pregnancy Complications, Infectious , Retention in Care , Anti-HIV Agents/therapeutic use , Child , Female , HIV Infections/drug therapy , HIV Infections/prevention & control , Humans , Infant , Infectious Disease Transmission, Vertical/prevention & control , Kenya , Nevirapine/therapeutic use , Pregnancy , Pregnancy Complications, Infectious/drug therapy , Pregnancy Complications, Infectious/prevention & control
8.
JBI Database System Rev Implement Rep ; 16(7): 1564-1581, 2018 07.
Article En | MEDLINE | ID: mdl-29995715

OBJECTIVE: The overall aim of this project was to assess compliance with evidence-based criteria regarding newborn resuscitation among healthcare workers in the maternity units in Maragua District Hospital (a busy district hospital in Kenya). INTRODUCTION: Globally, the majority of deaths under five years are attributable to neonatal causes. Perinatal asphyxia accounts for a significant portion of these deaths, especially in developing countries. These deaths are largely preventable, and interventions geared towards assisting newborns to initiate their first breath within the first minute of life have markedly reduced mortality. METHODS: This implementation project was conducted in the maternity units of a busy district hospital. Evidence-based audit criteria were developed on the basis of an evidence summary developed by the Joanna Briggs Institute (JBI). Using the JBI Practical Application of Clinical Evidence System software (JBI PACES), a baseline audit was conducted including a sample size of 55 healthcare providers and 300 patient case notes followed by an identification of potential barriers and strategies to overcome them. A follow-up audit including a sample size of 55 healthcare providers was conducted by using the same audit criteria. RESULTS: Improvements in practice were demonstrated in all criteria. The baseline audit demonstrated that three of the five audit criteria were found to be less than 50%, indicating moderate compliance with current evidence with regards to newborn resuscitation. Following implementation of the strategies, which included a six-week education and demonstrative skills training, and updating of the protocols and equipment, there was a significant improvement in all the criteria audited, with the first four criteria achieving 100% compliance, and the fifth criteria achieving 90% compliance. CONCLUSION: On completion of the project, the participants demonstrated an increase in knowledge and skills on newborn resuscitation, which led to a significant reduction in admission of newborns with birth asphyxia to the newborn unit.


Evidence-Based Practice , Guideline Adherence , Hospitals, District , Nursing Staff, Hospital/education , Resuscitation/standards , Humans , Infant, Newborn , Kenya , Resuscitation/methods
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