153 research outputs found
Neonatal EEG graded for severity of background abnormalities in hypoxic-ischaemic encephalopathy
This report describes a set of neonatal electroencephalogram (EEG) recordings
graded according to the severity of abnormalities in the background pattern.
The dataset consists of 169 hours of multichannel EEG from 53 neonates recorded
in a neonatal intensive care unit. All neonates received a diagnosis of
hypoxic-ischaemic encephalopathy (HIE), the most common cause of brain injury
in full term infants. For each neonate, multiple 1-hour epochs of good quality
EEG were selected and then graded for background abnormalities. The grading
system assesses EEG attributes such as amplitude and frequency, continuity,
sleep--wake cycling, symmetry and synchrony, and abnormal waveforms. Background
severity was then categorised into 4 grades: normal or mildly abnormal EEG,
moderately abnormal EEG, severely abnormal EEG, and inactive EEG. The data can
be used as a reference set of multi-channel EEG for neonates with HIE, for EEG
training purposes, or for developing and evaluating automated grading
algorithms
Increased System Fidelity for Navy Aviation Hypoxia Training
In 2009, the Naval Aviation Survival Training Program (NASTP) Trainer Management Team (TMT) identified a need for a next-generation normobaric mask-on hypoxia trainer with enhanced capabilities due to the lack of positive air pressure provided by existing capabilities. The lack of a positive pressure-on-demand airflow delivery for current mask-on hypoxia training has been cited as a potential training gap wherein 44% of students experience air hunger (Artino, Folga, & Vacchiano, 2009). As a result, it is unclear whether students are able to recognize more subtle symptoms of hypoxia or if they are masked by air hunger. To address this, researchers have investigated an innovative technology solution to deliver representative pressure-on-demand flow rates, thereby increasing training fidelity by replicating the air delivery method of aircraft systems. This research also provided an opportunity to seek additional novel advances. Reducing the logisitical footprint and increasing portability by removing the need for compressed gases was a goal to ease implementation within higher fidelity training simulators with limited space to increase immersive training opportunities. This paper will provide an overview of the training need and the technical approach to the training device development. Additionally, the authors will discuss the engineering and human subjects testing conducted to evaluate the system. The results will include how symptoms experienced using this novel device compare to historical data from other training systems, in addition to whether the system reduces or eliminates air hunger issues
Characterisation of neonatal seizures and their treatment using continuous EEG monitoring: a multicentre experience.
OBJECTIVE: The aim of this multicentre study was to describe detailed characteristics of electrographic seizures in a cohort of neonates monitored with multichannel continuous electroencephalography (cEEG) in 6 European centres. METHODS: Neonates of at least 36 weeks of gestation who required cEEG monitoring for clinical concerns were eligible, and were enrolled prospectively over 2 years from June 2013. Additional retrospective data were available from two centres for January 2011 to February 2014. Clinical data and EEGs were reviewed by expert neurophysiologists through a central server. RESULTS: Of 214 neonates who had recordings suitable for analysis, EEG seizures were confirmed in 75 (35%). The most common cause was hypoxic-ischaemic encephalopathy (44/75, 59%), followed by metabolic/genetic disorders (16/75, 21%) and stroke (10/75, 13%). The median number of seizures was 24 (IQR 9-51), and the median maximum hourly seizure burden in minutes per hour (MSB) was 21 min (IQR 11-32), with 21 (28%) having status epilepticus defined as MSB>30 min/hour. MSB developed later in neonates with a metabolic/genetic disorder. Over half (112/214, 52%) of the neonates were given at least one antiepileptic drug (AED) and both overtreatment and undertreatment was evident. When EEG monitoring was ongoing, 27 neonates (19%) with no electrographic seizures received AEDs. Fourteen neonates (19%) who did have electrographic seizures during cEEG monitoring did not receive an AED. CONCLUSIONS: Our results show that even with access to cEEG monitoring, neonatal seizures are frequent, difficult to recognise and difficult to treat. OBERSERVATION STUDY NUMBER: NCT02160171
Neonatal Seizure Management – Is the Timing of Treatment Critical?
OBJECTIVE: To assess the impact of the time to treatment of the first electrographic seizure on subsequent seizure burden; secondary aim was to describe overall seizure management in a large neonatal cohort. STUDY DESIGN: Newborns (36-44 weeks' gestation) requiring electroencephalographic (EEG) monitoring recruited to two multicentre European studies were included. Infants who received anti-seizure medication exclusively after electrographic seizure onset, were grouped based on time to treatment of the first seizure: ASM within 1-hour, ASM between 1-2 hours and ASM after 2-hours. Outcomes measured were seizure burden, maximum seizure burden, status epilepticus, number of seizures and ASM dose over 24-hours following seizure onset. RESULTS: Out of 472 newborns recruited, 154(32.6%) infants had confirmed electrographic seizures. Sixty-nine infants were exclusively treated after onset of electrographic seizures: 21 infants received ASM within 1 hour, 15 infants between 1-2 hours and 33 infants after 2 hours of seizure onset. Significantly lower seizure burden and less seizures were noted in infants treated with ASM within 1 hour from seizure onset (p value=0.029 and 0.035, respectively). Overall, 258/472(54.7%) infants received ASM throughout the study period, of which 40 infants without electrographic seizures had treatment during EEG monitoring and 11 infants with electrographic seizures had no treatment. CONCLUSION: Treatment of neonatal seizures may be time-critical, but more research is required to confirm this. We also need to improve neonatal seizure diagnosis and treatment
Challenges of developing robust AI for intrapartum fetal heart rate monitoring
Background: CTG remains the only non-invasive tool available to the maternity team for continuous monitoring of fetal well-being during labour. Despite widespread use and investment in staff training, difficulty with CTG interpretation continues to be identified as a problem in cases of fetal hypoxia, which often results in permanent brain injury. Given the recent advances in AI, it is hoped that its application to CTG will offer a better, less subjective and more reliable method of CTG interpretation. Objectives: This mini-review examines the literature and discusses the impediments to the success of AI application to CTG thus far. Prior randomised control trials (RCTs) of CTG decision support systems are reviewed from technical and clinical perspectives. A selection of novel engineering approaches, not yet validated in RCTs, are also reviewed. The review presents the key challenges that need to be addressed in order to develop a robust AI tool to identify fetal distress in a timely manner so that appropriate intervention can be made. Results: The decision support systems used in three RCTs were reviewed, summarising the algorithms, the outcomes of the trials and the limitations. Preliminary work suggests that the inclusion of clinical data can improve the performance of AI-assisted CTG. Combined with newer approaches to the classification of traces, this offers promise for rewarding future development
Validation of an automated seizure detection algorithm for term neonates
Objective: The objective of this study was to validate the performance of a seizure detection algorithm (SDA) developed by our group, on previously unseen, prolonged, unedited EEG recordings from 70 babies from 2 centres. Methods: EEGs of 70 babies (35 seizure, 35 non-seizure) were annotated for seizures by experts as the gold standard. The SDA was tested on the EEGs at a range of sensitivity settings. Annotations from the expert and SDA were compared using event and epoch based metrics. The effect of seizure duration on SDA performance was also analysed. Results: Between sensitivity settings of 0.5 and 0.3, the algorithm achieved seizure detection rates of 52.6–75.0%, with false detection (FD) rates of 0.04–0.36 FD/h for event based analysis, which was deemed to be acceptable in a clinical environment. Time based comparison of expert and SDA annotations using Cohen’s Kappa Index revealed a best performing SDA threshold of 0.4 (Kappa 0.630). The SDA showed improved detection performance with longer seizures. Conclusion: The SDA achieved promising performance and warrants further testing in a live clinical evaluation. Significance: The SDA has the potential to improve seizure detection and provide a robust tool for comparing treatment regimens
Neonatal Seizure Management - Is the Timing of Treatment Critical?
Objective: To assess the impact of the time to treatment of the first electrographic seizure on subsequent seizure burden and describe overall seizure management in a large neonatal cohort. Study design: Newborns (36-44 weeks of gestation) requiring electroencephalographic (EEG) monitoring recruited to 2 multicenter European studies were included. Infants who received antiseizure medication exclusively after electrographic seizure onset were grouped based on the time to treatment of the first seizure: antiseizure medication within 1 hour, between 1 and 2 hours, and after 2 hours. Outcomes measured were seizure burden, maximum seizure burden, status epilepticus, number of seizures, and antiseizure medication dose over the first 24 hours after seizure onset. Results: Out of 472 newborns recruited, 154 (32.6%) had confirmed electrographic seizures. Sixty-nine infants received antiseizure medication exclusively after the onset of electrographic seizure, including 21 infants within 1 hour of seizure onset, 15 between 1 and 2 hours after seizure onset, and 33 at >2 hours after seizure onset. Significantly lower seizure burden and fewer seizures were noted in the infants treated with antiseizure medication within 1 hour of seizure onset (P =.029 and.035, respectively). Overall, 258 of 472 infants (54.7%) received antiseizure medication during the study period, of whom 40 without electrographic seizures received treatment exclusively during EEG monitoring and 11 with electrographic seizures received no treatment. Conclusions: Treatment of neonatal seizures may be time-critical, but more research is needed to confirm this. Improvements in neonatal seizure diagnosis and treatment are also needed
Mechanisms and treatment of ischaemic stroke: insights from genetic associations
The precise pathophysiology of ischaemic stroke is unclear, and a greater understanding of the different mechanisms that underlie large-artery, cardioembolic and lacunar ischaemic stroke subtypes would enable the development of more-effective, subtype-specific therapies. Genome-wide association studies (GWASs) are identifying novel genetic variants that associate with the risk of stroke. These associations provide insight into the pathophysiological mechanisms, and present opportunities for novel therapeutic approaches. In this Review, we summarize the genetic variants that have been linked to ischaemic stroke in GWASs to date and discuss the implications of these associations for both our understanding and treatment of ischaemic stroke. The majority of genetic variants identified are associated with specific subtypes of ischaemic stroke, implying that these subtypes have distinct genetic architectures and pathophysiological mechanisms. The findings from the GWASs highlight the need to consider whether therapies should be subtype-specific. Further GWASs that include large cohorts are likely to provide further insights, and emerging technologies will complement and build on the GWAS findings
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