Postoperative Amplitude-Integrated Electroencephalography Predicts Four-Year Neurodevelopmental Outcome in Children with Complex Congenital Heart Disease

Neurological Impact of Slower Rewarming during Bypass Surgery in Infants

BACKGROUND

 Hypothermia is a neuroprotective strategy during cardiopulmonary bypass. Rewarming entailing a rapid rise in cerebral metabolism might lead to secondary neurological sequelae. In this pilot study, we aimed to validate the hypothesis that a slower rewarming rate would lower the risk of cerebral hypoxia and seizures in infants.

METHODS

 This is a prospective, clinical, single-center study. Infants undergoing cardiac surgery in hypothermia were rewarmed either according to the standard (+1°C in < 5 minutes) or a slow (+1°C in > 5-8 minutes) rewarming strategy. We monitored electrocortical activity via amplitude-integrated electroencephalography (aEEG) and cerebral oxygenation by near-infrared spectroscopy during and after surgery.

RESULTS

 Fifteen children in the standard rewarming group (age: 13 days [5-251]) were cooled down to 26.6°C (17.2-29.8) and compared with 17 children in the slow-rewarming group (age: 9 days [4-365]) with a minimal temperature of 25.7°C (20.1-31.4). All neonates in both groups (n = 19) exhibited suppressed patterns compared with 28% of the infants > 28 days (p < 0.05). During rewarming, only 26% of the children in the slow-rewarming group revealed suppressed aEEG traces (vs. 41%; p = 0.28). Cerebral oxygenation increased by a median of 3.5% in the slow-rewarming group versus 1.5% in the standard group (p = 0.9). Our slow-rewarming group revealed no aEEG evidence of any postoperative seizures (0 vs. 20%).

CONCLUSION

 These results might indicate that a slower rewarming rate after hypothermia causes less suppression of electrocortical activity and higher cerebral oxygenation during rewarming, which may imply a reduced risk of postoperative seizures.

Postoperative hypernatremia is associated with worse brain injuries on EEG and MRI following pediatric cardiac surgery

Objectives

Dysnatremia is a common electrolyte disturbance after cardiopulmonary bypass (CPB) surgery for congenital heart disease (CHD) and a known risk factor for adverse neurological events and clinical outcomes. The objective of this study was to evaluate the association of dysnatremia with worse abnormal EEG patterns, brain injuries detected by magnetic resonance imaging (MRI) and early adverse outcomes.

Methods

We monitored continuous EEG in 340 children during the initial 48 h following cardiac surgery. Demographics and clinical characteristics were recorded. Sodium concentrations were measured in the arterial blood gas analysis every 6 h. Hyponatremia and hypernatremia were classified by the average of sodium concentrations over 48 h. Postoperative cerebral MRI was performed before hospital discharge.

Results

In our patient cohort, dysnatremia was present in 46 (13.5%) patients. Among them, hyponatremia occurred in 21 (6.2%) and hypernatremia in 25 (7.4%). When compared to patients with normonatremia, hyponatremia was not associated with EEG abnormalities and early adverse outcomes (Ps ≥ .14). In hypernatremia group, the CPB time was significantly longer and more frequent use of DHCA (Ps ≤ .049). After adjusting for time, CPB time and the use of DHCA, hypernatremia was significantly associated with worse EEG abnormalities (including background, seizures and pathological delta brushes), more severe brain injuries on MRI (Ps ≤ .04) and trended to be associated with longer postoperative mechanical ventilation time (P = .06).

Conclusion

Hypernatremia and hyponatremia were common in children after cardiac surgery. Hypernatremia, but not hyponatremia, was significantly associated with worse EEG abnormalities and more severe brain injuries on MRI and extended postoperative mechanical ventilation time.

Perioperative EEG background and discharge abnormalities in children undergoing cardiac surgery: a prospective single-centre observational study

BACKGROUND

We analysed the characteristics of abnormal electroencephalogram (EEG) patterns before, during, and 48 h after cardiac surgery in patients with heterogeneous congenital heart disease to assess their relationship to demographic and perioperative variables and to early patient outcomes.

METHODS

In 437 patients enrolled in a single centre, EEG was evaluated for background (including sleep-wake cycle) and discharge (seizures, spikes/sharp waves, pathological delta brushes) abnormalities. Clinical data (arterial blood pressure, doses of inotropic drugs, and serum lactate concentrations) were recorded every 3 h. Postoperative brain MRI was performed before discharge.

RESULTS

Preoperative, intraoperative, and postoperative EEG was monitored in 139, 215, and 437 patients, respectively. Patients with a degree of preoperative background abnormalities (n=40) had more severe intraoperative and postoperative EEG abnormalities (P<0.0001). Intraoperatively, 106/215 (49.3%) patients progressed into an isoelectric EEG. Longer durations of isoelectric EEG were associated with more severe postoperative EEG abnormalities and brain injury on MRI (Ps≤0.003). Postoperative background abnormalities occurred in 218/437 (49.9%) patients, and 119 (54.6%) of them had not recovered after surgery. Seizures occurred in 36/437 (8.2%) patients, spikes/sharp waves in 359/437 (82.2%), and pathological delta brushes in 9/437 (2.0%). Postoperative EEG abnormalities correlated with degree of brain injury on MRI (Ps≤0.02). Demographic and perioperative variables were significantly correlated with postoperative EEG abnormalities, which in turn correlated with adverse clinical outcomes.

CONCLUSIONS

Perioperative EEG abnormalities occurred frequently and correlated with numerous demographic and perioperative variables and adversely correlated with postoperative EEG abnormalities and early outcomes. The relation of EEG background and discharge abnormalities with long-term neurodevelopmental outcomes remains to be explored.

Continuous electroencephalography (cEEG) in infants with congenital heart disease (CHD)

BACKGROUND

Neonates with congenital heart disease (CHD) undergoing cardiopulmonary bypass (CPB) surgery have increased risk of impaired neurodevelopmental outcomes secondary to brain injury. This study aims to characterize pre- and post-operative continuous EEG (cEEG) patterns to detect abnormal cerebral activity in infants with CHD and investigate whether an association exists between the degree of encephalopathy in pre- and post-operative cEEG.

METHODS

This retrospective cohort study conducted between 2010 and 2018 at a tertiary hospital in Cleveland, OH included infants with CHD with cEEG monitoring, who underwent CPB surgery within first 6 months of life.

RESULTS

Study included 77 patients, of which 61% were males who were operated at median age 6 days. Pre-operatively, 69% and 87% had normal cEEG and sleep-wake cycles, respectively. Post-operatively, 80% had abnormal cEEG. Longer circulatory arrest time and CPB were associated with lack of continuity (p 0.011), excessive discontinuity (p 0.007) and prolonged inter-burst interval (IBI) duration (p value < 0.001). A significant association existed between severity of encephalopathy in immediate and 24-h post-operative period (p value < 0.001).

CONCLUSIONS

More than 80% of neonates with CHD have abnormal post-operative EEG. Longer circulatory arrest time and CPB were associated with lack of continuity, excessive discontinuity, and prolonged IBI duration on post-operative EEG.

IMPACT

This study shows that majority of neonates with congenital heart disease (CHD) have normal pre-operative EEG with a continuous background and normal sleep-wake cycles. Also, 80% of neonates had abnormal post-operative EEG. Longer duration of arrest time and bypass time was associated with lack of continuity, excessive discontinuity, and prolonged IBI duration during post-operative EEG monitoring. These findings will help clinicians when counseling parents in the intensive care unit, risk stratification, and long-term neurodevelopmental monitoring in these high-risk patients.

Pediatric Intensive Care Unit Patients: Sedation, Monitoring, and Neurodevelopmental Outcomes

The design and conduct of pediatric sedation studies in critically ill patients have historically been challenging due to the complexity of the pediatric intensive care unit (PICU) environment and the difficulty of establishing equipoise. Clinical trials, for instance, represent 1 important means of advancing our knowledge in this field, but there is a paucity of such studies in the literature. Accounting for ground-level factors in planning for each trial phase (eg, enrollment, intervention, assessment, and follow-up) and the presence of broader system limitations is of key importance. In addition, there is a need for early planning, coordination, and obtaining buy-in from individual study sites and staff to ensure success, particularly for multicenter studies. This review synthesizes the current state of pediatric sedation research and the myriad of challenges in designing and conducting successful trials in this particular area. The review poses consideration for future research directions, including novel study designs, and discusses electroencephalography monitoring and neurodevelopmental outcomes of PICU survivors.

Neuromonitoring, neuroimaging, and neurodevelopmental follow-up practices in neonatal congenital heart disease: a European survey

BACKGROUND

Brain injury and neurodevelopmental impairment remain a concern in children with complex congenital heart disease (CHD). A practice guideline on neuromonitoring, neuroimaging, and neurodevelopmental follow-up in CHD patients undergoing cardiopulmonary bypass surgery is lacking. The aim of this survey was to systematically evaluate the current practice in centers across Europe.

METHODS

An online-based structured survey was sent to pediatric cardiac surgical centers across Europe between April 2019 and June 2020. Results were summarized by descriptive statistics.

RESULTS

Valid responses were received by 25 European centers, of which 23 completed the questionnaire to the last page. Near-infrared spectroscopy was the most commonly used neuromonitoring modality used in 64, 80, and 72% preoperatively, intraoperatively, and postoperatively, respectively. Neuroimaging was most commonly performed by means of cranial ultrasound in 96 and 84% preoperatively and postoperatively, respectively. Magnetic resonance imaging was obtained in 72 and 44% preoperatively and postoperatively, respectively, but was predominantly reserved for clinically symptomatic patients (preoperatively 67%, postoperatively 64%). Neurodevelopmental follow-up was implemented in 40% of centers and planned in 24%.

CONCLUSIONS

Heterogeneity in perioperative neuromonitoring and neuroimaging practice in CHD in centers across Europe is large. The need for neurodevelopmental follow-up has been recognized. A clear practice guideline is urgently needed.

IMPACT

There is large heterogeneity in neuromonitoring, neuroimaging, and neurodevelopmental follow-up practices among European centers caring for neonates with complex congenital heart disease. This study provides a systematic evaluation of the current neuromonitoring, neuroimaging, and neurodevelopmental follow-up practice in Europe. The results of this survey may serve as the basis for developing a clear practice guideline that could help to early detect and prevent neurological and neurodevelopmental sequelae in neonates with complex congenital heart disease.

Newborns at high risk for brain injury: the role of the amplitude-integrated electroencephalography

OBJECTIVE

Amplitude-integrated electroencephalography (aEEG) is a simplified bedside neurophysiology tool that has been implemented in the neonatal intensive care unit and studied in an extensive range of clinical applications in the past decade. This critical review aimed to evaluate a variety of clinical applications of aEEG monitoring in diagnosis, clinical management, and prognosis assessment in critically ill neonates.

SOURCES

The databases of Pubmed, SciELO, Lilacs, and Cochrane, books, and other online resources were consulted, as well as sources of professional experiences.

SUMMARY OF FINDINGS

The clinical use of aEEG to access real-time brain function, background activity, and utility in seizures detection has been described. A critical review was realized considering the authors' professional experience. Newborns with hypoxic-ischemic encephalopathy and seizures screening represent the most common studied population. However, several studies have shown interesting applications on preterm infants, newborns with congenital heart disease, and other clinical situations of high risk of injury to the developing brain.

CONCLUSION

The aEEG has shown to be a useful non-invasive bedside monitor that aids in evaluating brain function, background activity, and cyclicity. aEEG findings have also demonstrated good prognostic value in a group of critically ill neonates. The aEEG seizure diagnosis capability has limitations, which have been already well established. The use of neonatal brain monitoring such as aEEG was shown to give valuable information in several high-risk clinical situations.

Incidence, risk factors, and outcomes in electroencephalographic seizures after mechanical circulatory support: A systematic review and meta-analysis

Purpose

To estimate the overall incidence, risk factors, and clinical outcomes of electroencephalographic (EEG) seizures for adults and children after mechanical circulatory support (MCS).

Method and measurements

This systematic review and meta-analysis were carried out in accordance with the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) guidance document. MEDLINE EMBASE and CENTRAL were investigated for relevant studies. The related information was retrieved by two independent reviewers and all analyses were conducted by STATA (version 16.0; Stata Corporation, College Station, TX, United States).

Result

Sixty studies including 36,191 adult and 55,475 pediatric patients with MCS were enrolled for evaluation. The study showed that the overall incidence of EEG seizures in adults was 2% (95%CI: 1–3%), in which 1% (95%CI: 1–2%) after cardiopulmonary bypass (CPB), and 3% (95%CI: 1–6%) after extracorporeal membrane oxygenation (ECMO). For pediatrics patients, the incidence of EEG seizures was 12% (95%CI: 11–14%), among which 12% (9–15%) after CPB and 13% (11–15%) after ECMO. The major risk factors of EEG seizures after MCS in adults were redo surgery (coefficient = 0.0436, p = 0.044), and COPD (coefficient = 0.0749, p = 0.069). In addition, the gestational week of CPB (coefficient = 0.0544, p = 0.080) and respiratory failure of ECMO (coefficient = –0.262, p = 0.019) were also indicated to be associated with EEG seizures in pediatrics.

Conclusion

EEG seizures after MCS were more common in pediatrics than in adults. In addition, the incidence of EEG seizure after ECMO was higher than CPB both in adults and children. It is expected that appropriate measures should be taken to control modifiable risk factors, thus improving the prognosis and increasing the long-term survival rate of MCS patients.

Systematic Review Registration

[https://www.crd.york.ac.uk/prospero], identifier [CRD42021287288].

The impact of prematurity and associated comorbidities on clinical outcomes in neonates with congenital heart disease

Prematurity is a common risk factor in children, affecting approximately 10% of live births, globally. It is more common in children with critical congenital heart disease (CCHD) and carries important implications in this group of patients. While outcomes have been improving over the years, even late preterm birth is associated with worse outcomes in children born with critical congenital heart disease compared to those without. Infants with both prematurity and CCHD are at particularly high risk for important comorbidities, including: necrotizing enterocolitis, intraventricular hemorrhage, white matter injury, neurodevelopmental anomalies and retinopathy of prematurity. Lesion-specific intensive care management of these infants, interventional and peri-operative management specifically tailored to their needs, and multidisciplinary care all have the potential to improve outcomes in this challenging group.

Current Status and Future Directions of Neuromonitoring With Emerging Technologies in Neonatal Care

Neonatology has experienced a significant reduction in mortality rates of the preterm population and critically ill infants over the last few decades. Now, the emphasis is directed toward improving long-term neurodevelopmental outcomes and quality of life. Brain-focused care has emerged as a necessity. The creation of neonatal neurocritical care units, or Neuro-NICUs, provides strategies to reduce brain injury using standardized clinical protocols, methodologies, and provider education and training. Bedside neuromonitoring has dramatically improved our ability to provide assessment of newborns at high risk. Non-invasive tools, such as continuous electroencephalography (cEEG), amplitude-integrated electroencephalography (aEEG), and near-infrared spectroscopy (NIRS), allow screening for seizures and continuous evaluation of brain function and cerebral oxygenation at the bedside. Extended and combined uses of these techniques, also described as multimodal monitoring, may allow practitioners to better understand the physiology of critically ill neonates. Furthermore, the rapid growth of technology in the Neuro-NICU, along with the increasing use of telemedicine and artificial intelligence with improved data mining techniques and machine learning (ML), has the potential to vastly improve decision-making processes and positively impact outcomes. This article will cover the current applications of neuromonitoring in the Neuro-NICU, recent advances, potential pitfalls, and future perspectives in this field.

Protecting brains and saving futures guidelines: A prospective, multicenter, and observational study on the use of telemedicine for neonatal neurocritical care in Brazil

Background

Management of high-risk newborns should involve the use of standardized protocols and training, continuous and specialized brain monitoring with electroencephalography (EEG), amplitude integrated EEG, Near Infrared Spectroscopy, and neuroimaging. Brazil is a large country with disparities in health care assessment and some neonatal intensive care units (NICUs) are not well structured with trained personnel able to provide adequate neurocritical care. To reduce this existing gap, an advanced telemedicine model of neurocritical care called Protecting Brains and Saving Futures (PBSF) Guidelines was developed and implemented in a group of Brazilian NICUs.

Methods

A prospective, multicenter, and observational study will be conducted in all 20 Brazilian NICUs using the PBSF Guidelines as standard-of-care. All infants treated accordingly to the guidelines during Dec 2021 to Nov 2024 will be eligible. Ethical approval was obtained from participating centers. The primary objective is to describe adherence to the PBSF Guidelines and clinical outcomes, by center and over a 3-year period. Adherence will be measured by quantification of neuromonitoring, neuroimaging exams, sub-specialties consultation, and clinical case discussions and videoconference meetings. Clinical outcomes of interest are detection of seizures during hospitalization, use of anticonvulsants, inotropes, and fluid resuscitation, death before hospital discharge, length of hospital stay, and referral of patients to specialized follow-up.

Discussion

The study will provide evaluation of PBSF Guidelines adherence and its impact on clinical outcomes. Thus, data from this large prospective, multicenter, and observational study will help determine whether neonatal neurocritical care via telemedicine can be effective. Ultimately, it may offer the necessary framework for larger scale implementation and development of research projects using remote neuromonitoring.

Trial registration

NCT03786497, Registered 26 December 2018, https://www.clinicaltrials.gov/ct2/show/NCT03786497?term=protecting+brains+and+saving+futures&draw=2&rank=1.

Functional brain maturation and sleep organisation in neonates with congenital heart disease

OBJECTIVE

Neonates with Congenital Heart Disease (CHD) have structural delays in brain development. To evaluate whether functional brain maturation and sleep-wake physiology is also disturbed, the Functional Brain Age (FBA) and sleep organisation on EEG during the neonatal period is investigated.

METHODS

We compared 15 neonates with CHD who underwent multichannel EEG with healthy term newborns of the same postmenstrual age, including subgroup analysis for d-Transposition of the Great Arteries (d-TGA) (n = 8). To estimate FBA, a prediction tool using quantitative EEG features as input, was applied. Second, the EEG was automatically classified into the 4 neonatal sleep stages. Neonates with CHD underwent neurodevelopmental testing using the Bayley Scale of Infant Development-III at 24 months.

RESULTS

Preoperatively, the FBA was delayed in CHD infants and more so in d-TGA infants. The FBA was positively correlated with motor scores. Sleep organisation was significantly altered in neonates with CHD. The duration of the sleep cycle and the proportion of Active Sleep Stage 1 was decreased, again more marked in the d-TGA infants. Neonates with d-TGA spent less time in High Voltage Slow Wave Sleep and more in Tracé Alternant compared to healthy terms. Both FBA and sleep organisation normalised postoperatively. The duration of High Voltage Slow Wave Sleep remained positively correlated with motor scores in d-TGA infants.

INTERPRETATION

Altered early brain function and sleep is present in neonates with CHD. These results are intruiging, as inefficient neonatal sleep has been linked with adverse long-term outcome. Identifying how these rapid alterations in brain function are mitigated through improvements in cerebral oxygenation, surgery, drugs and nutrition may have relevance for clinical practice and outcome.

aEEG as a useful tool for neuromonitoring in critically ill children - Current evidence and knowledge gaps

AIM

Amplitude-integrated electroencephalography (aEEG) is used in children beyond neonatal age, but systematic investigations have been lacking. This mini-review summarised aEEG studies on children aged one month to 18 years, evaluated the usefulness of aEEG and identified knowledge gaps or limitations.

METHODS

We searched the PubMed database for articles published in English up to September 2020, and 23 papers were identified.

RESULTS

aEEG was frequently used to compensate for the absence of continuous full-channel EEG monitoring, particularly for detecting seizures. Interpreting background patterns was based on neonatal classifications, as reference values for older infants and children are lacking. It is possible that aEEG could predict outcomes after paediatric cardiac arrests and other conditions. Gaps in our knowledge exist with regard to normal values in healthy children and the effects of sedation on aEEG background patterns in children.

CONCLUSION

The main application of aEEG was detecting and treating paediatric seizures. Further research should determine reference values and investigate the potential to predict outcome after critical events or in acute neurological disease. It is likely that aEEG will play a role in paediatric critical care in the future.

Characterization of aEEG During Sleep and Wakefulness in Healthy Children

INTRODUCTION

Interpretation of amplitude-integrated EEG (aEEG) is hindered by lacking knowledge on physiological background patterns in children. The aim of this study was to find out whether aEEG differs between wakefulness and sleep in children.

METHODS

Forty continuous full-channel EEGs (cEEG) recorded during the afternoon and overnight in patients <18 years of age without pathologies or only solitary interictal epileptiform discharges were converted into aEEGs. Upper and lower amplitudes of the C3-C4, P3-P4, C3-P3, C4-P4, and Fp1-Fp2 channels were measured during wakefulness and sleep by two investigators and bandwidths (BW) calculated. Sleep states were assessed according to the American Academy of Sleep Medicine. Median and interquartile ranges (IQR) were calculated to compare the values of amplitudes and bandwidth between wakefulness and sleep.

RESULTS

Median age was 9.9 years (IQR 6.1-14.7). All patients displayed continuous background patterns. Amplitudes and BW differed between wakefulness and sleep with median amplitude values of the C3-C4 channel 35 μV (IQR: 27-49) for the upper and 13 μV (10-19) for the lower amplitude. The BW was 29 μV (21-34). During sleep, episodes with high amplitudes [upper: 99 μV (71-125), lower: 35 μV (25-44), BW 63 μV (44-81)] corresponded to sleep states N2-N3. High amplitude-sections were interrupted by low amplitude-sections, which became the longer toward the morning [upper amplitude: 39 μV (30-51), lower: 16 μV (11-20), BW 23 μV (19-31)]. Low amplitude-sections were associated with sleep states REM, N1, and N2. With increasing age, amplitudes and bandwidths declined.

CONCLUSION

aEEGs in non-critically ill children displayed a wide range of amplitudes and bandwidths. Amplitudes were low during wakefulness and light sleep and high during deep sleep. Interpretation of pediatric aEEG background patterns must take into account the state of wakefulness in in clinical practice and research.

Effect of perioperative amplitude-integrated electroencephalography on neurodevelopmental outcomes following infant heart surgery

The purpose of the current study was to determine the effect of perioperative amplitude-integrated electroencephalography (aEEG) on neurodevelopmental outcomes in infants with congenital heart disease (CHD). A total of 93 children with CHD were included in the current study. All patients enrolled in the present study had undergone cardiac surgery prior to 3 months of age and pre- or postoperative aEEG was monitored. Participants were assessed after 1 year using the Bayley Scales of Infant Test. A total of 82.2% of infants exhibited continuous normal voltage preoperatively (CNV) and 93.7% exhibited CNV postoperatively. Seizures were indicated in 2 infants preoperatively and 3 infants postoperatively. Compared with infants with PDI, infants with cyanotic CHD (β=17.218) exhibited a significantly lower MDI, an increased length of intensive care stay, and lower PDI scores (β=-0.577). Infants that underwent surgery with CPB exhibited higher PDI scores (β=11.956). Infants that exhibited behavioral problems also had lower PDI scores (β=-10.605). An abnormal preoperative background pattern and an absent postoperative SWC independently predicted poorer motor (P=0.014) and cognitive (P=0.049) outcomes at 1 year. The current study demonstrated that infants with CHD who underwent cardiac surgery prior to 3 months of age exhibited delayed neurodevelopmental outcomes, and that an aEEG assessment can aid in predicting these outcomes following surgery.

Intraoperative Cortical Asynchrony Predicts Abnormal Postoperative Electroencephalogram

BACKGROUND

Postoperative electroencephalograms (EEGs) can identify seizure activity and neurologic dysfunction in high-risk neonates requiring cardiac surgical procedures. Although intraoperative EEG monitoring is uncommon, variations in cerebral blood flow and temperature during antegrade cerebral perfusion (ACP) can manifest as cortical asynchrony during EEG monitoring. We hypothesized that intraoperative EEG cortical asynchrony would identify neonates at risk for abnormal postoperative EEG tracings.

METHODS

Neonates requiring ACP for cardiac repair or palliation had continuous baseline, intraoperative, and postoperative hemodynamic and EEG monitoring. Synchronous and asynchronous cortical bursts were quantified during (1) cooling before ACP, (2) ACP, and (3) rewarming. Asynchronous bursts were defined as interhemispheric variations in electrical voltage or frequency. Neonates were divided into 2 groups, those with and without an abnormal postoperative EEG, which was defined as either persistent asynchrony for more than 2 hours or seizure activity on EEG.

RESULTS

Among 40 neonates, 296 asynchronous bursts were noted, most commonly during rewarming. Eight (20%) neonates had an abnormal postoperative EEG (seizure activity, n = 3; persistent asynchrony, n = 5). Baseline demographics and intraoperative hemodynamics were similar between the groups. However, the total number of intraoperative asynchronous bursts was greater in neonates with an abnormal postoperative EEG (17 [11, IQR:24] vs 3 [IQR:1, 7]; P < .001). Multivariate analysis confirmed that the number of asynchronous bursts was independently associated with an abnormal postoperative EEG (odds ratio,1.35; confidence interval,:1.10, 1.65; P = .004).

CONCLUSIONS

Neonates with a greater number of intraoperative asynchronous cortical bursts had an abnormal postoperative EEG.

Evaluation of maturity of sleep states in preterm infants using conventional and amplitude-integrated electroencephalography

OBJECTIVE

To determine whether sleep state maturity can be estimated accurately using conventional electroencephalography (cEEG) or amplitude-integrated electroencephalography (aEEG) features concerning sleep in neurologically unimpaired preterm infants.

METHODS

A total of 51 preterm infants were monitored with cEEG-polygraphy and simultaneous aEEG. Sleep state maturity of EEG corresponded to specific postmenstrual age (PMA). PMA on cEEG was blindly estimated according to cEEG patterns (indicated as background continuity, frequencies, and voltages) as well as developmental markers in specific states. PMA on aEEG was blindly estimated based on the cycling score (cycling representing sleep state transitions) according to a pre-established scoring system.

RESULTS

A total of 51 EEGs recorded between 32 and 37 weeks PMA were analysed. A significant relationship between estimated PMA (ePMA) and actual chronological PMA (cPMA) was shown by linear regression both on cEEG (r = 0.93, β = 0.98, 95% confidence interval (CI) 0.87-1.09, p < 0.001) and aEEG (r = 0.85, β = 0.83, 95% CI 0.69-0.98, p < 0.001). The estimation gap (defined as ePMA minus cPMA) was between -2 and +2 weeks both on cEEG and aEEG. The percentage of estimation gap between -1 and +1 weeks was 96% for cEEG, which was higher than the estimate of 88% for aEEG.

CONCLUSION

Estimated maturity of sleep state was well correlated with cPMA both on cEEG and aEEG. PMA corresponding to state maturity could be estimated within two weeks of actual cPMA using either of these two tools. However, cEEG had higher accuracy compared with aEEG in the evaluation of sleep state maturity.

Cognitive outcome of early school-aged children born very preterm is not predicted by early short-term amplitude-integrated electroencephalography

AIM

We investigated the association between early amplitude-integrated electroencephalography (aEEG) and cognitive outcome in very preterm infants at early school-age.

METHODS

This prospective cohort study, conducted in the Department of Neonatology, University Hospital Zurich, Switzerland, from 2009 to 2012, comprised of infants born at <32 weeks of gestation, who underwent continuous aEEG recording during the first 4 days of life. Cognitive outcome was assessed with the Kaufman-Assessment Battery for Children at 5 years. Univariate and multivariate logistic regressions were calculated between aEEG parameters and normal cognitive outcome, defined as an intelligence quotient (IQ) of at least 85.

RESULTS

The 118 (52.5% male) infants were born at a mean gestational age of 29.9 weeks and a mean birth weight of 1235 ± 363 g. We followed up 89 children at the age of five, and they had a mean IQ of 97.8 ± 12.7 with 21.3% under 85-and 2.2% had cerebral palsy. Univariate analyses found associations between aEEG measures and normal cognitive outcome, but these were no longer significant after adjustment for confounders. Socioeconomic status and neonatal morbidity were independent predictors of cognitive outcome.

CONCLUSION

Early short-term aEEG did not predict later cognitive outcome in our cohort of very preterm infants.

Neurodevelopmental Outcomes Among Children With Congenital Heart Disease: At-Risk Populations and Modifiable Risk Factors

As survivable outcomes among patients with complex congenital heart disease (cCHD) have continued to improve over the last several decades, more attention is being dedicated to interventions that impact not just survival but quality of life among patients with cCHD. In particular, patients with cCHD are at risk for impaired neurodevelopmental outcomes. In this review summarizing select presentations given at the 14th Annual Pediatric Cardiac Intensive Care Society's Annual Meeting in 2019, we discuss the neurodevelopmental phenotype of patients with cCHD, patients at greatest risk of impaired development, and three specific modifiable risk factors impacting development.

Amplitude-Integrated EEG for Neurological Assessment and Seizure Detection in a German Pediatric Intensive Care Unit

Objective: The aim of our study was to assess the use of aEEG in our pediatric intensive care unit (PICU), indications for neuromonitoring and its findings, utility for seizure detection, and associations with outcome. Design: We retrospectively analyzed non-neonates who were treated in our PICU and received amplitude-integrated EEG (aEEG). Patients: 27 patients aged between 29 days and 10 0/12 years (median 7.3 months) were included, who received a total of 35 aEEGS. Measurements: aEEG tracings were assessed for background (BG) pattern and its evolution, seizures, and side differences using a visual classification (Hellström-Westas). Clinical data were collected from patients' histories and analyzed for correlation with aEEG findings. Main results: While rare in early years, there was an increase in use over time. Most aEEGs were conducted because of (suspected) seizures or for management of antiepileptic treatment. aEEG had low sensitivity but high specificity for recognition of pathological BG pattern with reference to conventional EEG. Worsening of BG pattern or failure to improve was associated with death. Seizure detection rates by aEEG were higher than by clinical observation, especially for identification of non-convulsive epileptic state (ES). Side differences in aEEG were rare, but if present, they were associated with unilateral brain injury. Conclusions: aEEG is useful for the detection of seizures and ES in pediatric intensive care patients. Abnormal BG pattern and poor evolution of BG are negatively associated with survival. aEEG is a potential supplement to conventional EEG, facilitating long-term surveillance of cerebral function when continuous full-channel EEG is not available. Further investigation is needed.

Neurodevelopmental outcome of children with congenital heart disease

Congenital heart disease (CHD) constitutes the most common congenital malformation, with moderate or severe CHD occurring in around 6 in 1000 live births. Due to advances in medical care, survival rates have increased significantly. Thus, the majority of children with CHD survive until adolescence and adulthood. Children with CHD requiring cardiopulmonary bypass surgery are at risk for neurodevelopmental impairments in various domains, including mild impairments in cognitive and neuromotor functions, difficulties with social interaction, inattention, emotional symptoms, and impaired executive function. The prevalence for these impairments ranges from 20% to 60% depending on age and domain ("high prevalence-low severity"). Domains are often affected simultaneously, leading to school problems with the need for learning support and special interventions. The etiology of neurodevelopmental impairments is complex, consisting of a combination of delayed intrauterine brain development and newly occurring perioperative brain injuries. Mechanisms include altered intrauterine hemodynamic flow as well as neonatal hypoxia and reduced cerebral blood flow. The surgical procedure and postoperative phase add to this cascade of factors interfering with normal brain development. Early identification of children at high risk through structured follow-up programs is mandated to provide individually tailored early interventions and counseling to improve developmental health.

Amplitude-Integrated Electroencephalography for Early Recognition of Brain Injury in Neonates with Critical Congenital Heart Disease

OBJECTIVE

To study perioperative amplitude-integrated electroencephalography (aEEG) as an early marker for new brain injury in neonates requiring cardiac surgery for critical congenital heart disease (CHD).

STUDY DESIGN

This retrospective observational cohort study investigated 76 neonates with critical CHD who underwent neonatal surgery. Perioperative aEEG recordings were evaluated for background pattern (BGP), sleep-wake cycling (SWC), and ictal discharges. Spontaneous activity transient (SAT) rate, inter-SAT interval (ISI), and percentage of time with an amplitude <5 µV were calculated. Routinely obtained preoperative and postoperative magnetic resonance imaging of the brain were reviewed for brain injury (moderate-severe white matter injury, stroke, intraparenchymal hemorrhage, or cerebral sinovenous thrombosis).

RESULTS

Preoperatively, none of the neonates showed an abnormal BGP (burst suppression or worse) or ictal discharges. Postoperatively, abnormal BGP was seen in 18 neonates (24%; 95% CI, 14%-33%) and ictal discharges was seen in 13 neonates (17%; 95% CI, 8%-26%). Abnormal BGP and ictal discharges were more frequent in neonates with new postoperative brain injury (P = .08 and .01, respectively). Abnormal brain activity (ie, abnormal BGP or ictal discharges) was the single risk factor associated with new postoperative brain injury in multivariable logistic regression analysis (OR, 4.0; 95% CI, 1.3-12.3; P = .02). Postoperative SAT rate, ISI, or time <5 µV were not associated with new brain injury.

CONCLUSION

Abnormal brain activity is an early, bedside marker of new brain injury in neonates undergoing cardiac surgery. Not only ictal discharges, but also abnormal BGP, should be considered a clear sign of underlying brain pathology.

Amplitude-integrated electroencephalography during the first 72 h after birth in neonates diagnosed prenatally with congenital heart disease

BackgroundLittle is known on amplitude-integrated electroencephalography (aEEG) during the first few days after birth in neonates with congenital heart disease (CHD). Our aim was, therefore, to assess electrocortical activity using aEEG within the first 72 h after birth in neonates diagnosed prenatally with CHD, and to define independent prenatal and postnatal predictors for abnormal aEEG.MethodsNeonates with CHD who were admitted to the neonatal intensive care unit between 2010 and 2017 were retrospectively included. We assessed aEEG background patterns, sleep-wake cycling, and epileptic activity during the first 72 h after birth and defined prenatal and postnatal clinical parameters associated with aEEG patterns.ResultsSeventy-two neonates were included. Twenty-six (36%) had mildly abnormal and six (8%) had severely abnormal aEEG background patterns at some point during the study period. Sleep-wake cycling was present in 97% of the neonates. Subclinical seizures were common (15%), whereas none of the neonates had clinical seizures. Only treatment with sedatives was a significant predictor for abnormal aEEG background patterns, explaining 56% of the variance.ConclusionAbnormal aEEG background patterns are common and are strongly associated with treatment with sedatives in neonates with prenatally diagnosed CHD. Future studies should assess the association between early postnatal aEEG abnormalities and neurodevelopmental outcome.

Neurodevelopmental Profiles of Children with Congenital Heart Disease at School Age

OBJECTIVES

To assess 6-year neurodevelopmental outcomes in a current cohort of children with congenital heart disease (CHD) who underwent cardiopulmonary bypass surgery (CPB), and to determine risk factors for adverse outcomes.

STUDY DESIGN

Outcomes were examined in 233 prospectively enrolled children with CHD (including 64 with a recognized genetic disorder) who underwent CPB between 2004 and 2009. Follow-up assessment included standardized neurologic, motor, and cognitive tests. Variables were collected prospectively, and multiple regression analysis was performed to determine independent risk factors for adverse outcome.

RESULTS

The mean patient age at assessment was 6.3 years (range, 5.1-6.8 years). IQ was lower in children with a genetic disorder (median, 55; range, 17-115) compared with children without a genetic disorder (median, 95; range, 47-135; P < .001). Cognitive and motor performance also were lower in children without a genetic disorder compared with the norm (P < .01 for both). The prevalence of children without a genetic disorder performing below -2 SD (IQ 70) was higher than the norm (5.3% vs 2.3%; P = .008), and the prevalence of poor motor performance (<10th percentile) ranged from 21.2% to 41.1% (P < .01 for all). Significant independent risk factors for poor neurodevelopmental outcome included a genetic disorder, longer length of intensive care stay, lower birth weight, postoperative seizures, and lower socioeconomic status.

CONCLUSIONS

Current cohorts of children with CHD undergoing CPB show favorable outcomes but remain at risk for long-term neurodevelopmental impairments, particularly those with a genetic disorder and a complicated postoperative course. Close neurodevelopmental surveillance is necessary to provide early therapeutic support.