The brain in pediatric critical care: unique aspects of assessment, monitoring, investigations, and follow-up

Intraoperative Assessment of Cerebral Autoregulation With Cerebral Oximetry Index in Neonates Undergoing Cardiac Surgery: A Pilot Study

OBJECTIVE

To investigate cerebral autoregulation impairment during neonatal cardiac surgery.

DESIGN

A retrospective observational study.

SETTING

Single-center, university teaching children's hospital.

PARTICIPANTS

Neonates undergoing surgery for critical congenital heart defects.

INTERVENTIONS

Calculation of the cerebral oximetry index (COx) and COx-derived parameters was performed by processing signals from intraoperative routine monitoring.

MEASUREMENTS AND MAIN RESULTS

High-resolution intraoperative data were retrieved from a cohort of 16 term neonates. COx was calculated as the linear correlation between mean arterial blood pressure and cerebral oximetry in a 5-minute moving time window. Averaged COx values were obtained before, during, and after cardiopulmonary bypass (CPB), and comparisons were made using the Kruskal-Wallis test. A linear mixed-effects model was used to examine the associations between COx and other intraoperative physiological variables. Intraoperative limits of autoregulation for a COx cut-off of 0.3 were identified by combining data from the entire cohort. The median COx was 0.02 (interquartile range [IQR], -0.08 to 0.13) pre-CPB, 0.34 (IQR, 0.18-0.43) during CPB, and 0.26 (IQR, 0.05-0.38) post-CPB. Intraoperative evolution of COx was linearly associated with changes in cerebral oximetry, pO2, and core temperature but not with mean arterial pressure and pCO2. For the entire cohort, the intraoperative lower and upper limits of autoregulation were 35 mmHg and 59 mmHg, respectively.

CONCLUSIONS

Cerebral autoregulation was impaired during CPB and remained altered after separation from bypass. Real-time monitoring of the COx may be useful for identifying autoregulation disturbances and providing a more individualized approach to CPB management.

Analysis of the survival journey and post-traumatic growth process of children and their families following paediatric intensive care unit admission: A grounded theory study

OBJECTIVES

Advances in critical care technology have lowered mortality rates among critically ill individuals. Nonetheless, survivors and their families may develop new physical, mental, cognitive, and social challenges due to paediatric intensive care unit (PICU) treatments, impacting their quality of life. The aim of this study was to investigate the survival journey and post-traumatic growth process of children and their families following PICU admission within the Chinese cultural context.

METHODS

Twenty-six children who have been or are currently admitted to the PICU, alongside their parents and three PICU nurses, were chosen through purposive and theoretical sampling. Data collection involved face-to-face interviews and observations, with data analysis conducted through continuous comparison, open coding, and selective coding techniques.

FINDINGS

A model outlining the survival journey and post-traumatic growth process of critically ill children and their families post PICU admission has been established. This model encompasses two central trajectories: an upward trajectory consisting of confusion, charging, action, and sublimation phases and a downward trajectory comprising confusion, doubt and fear, inhibition (including confrontation and avoidance), and drowning phases.

CONCLUSIONS

Critically ill children and their families encounter diverse survival experiences and psychological journeys following traumatic events in the PICU. The survival experience has alternative upwards or downwards trajectories that are flexible/adaptable. Hence, offering timely psychological support can alter their developmental trajectories and foster post-traumatic growth.

Nursing insights on the effectiveness of automated pupillometry in two distinct pediatric intensive care units

PURPOSE

Automated pupillometry (AP) facilitates objective pupillary assessment. In this study, we aimed at assessing nursing perspective about the utility of AP in neurocritically ill children to understand acceptance and usage barriers to guide development of a standardized use protocol.

METHODS

We conducted a web-based, cross-sectional, anonymous, Google™ survey of nurses at two independent pediatric ICUs which have been using AP over last four years. The survey included questions related to user-friendliness, barriers, acceptance, frequency of use, and method of documenting AP findings.

RESULTS

A total of 31 nurses responded to the survey. A total of 25 nurses (80.6%) used the automated pupillometer and 19 (61.3%) nurses preferred to use the automated pupillometer on critically ill intubated patients. Respondents rated the pupillometer a median [IQR] frequency of use of 7/10 [4-9] and a mean user-friendliness of 8/10 [7-10]. Barriers to pupillometer use included pupillometer unavailability, technical issues, lack of perceived clinical significance, and infection control.

CONCLUSION

Nurses have widely adopted the use of automated pupillometer in the PICU especially for critically ill intubated patients and rate it favorably for user-friendliness. Barriers against its use include limited resources, infection concerns, technical issues, and a lack of perceived clinical significance and training. Implementation of standardized PICU protocol for AP usage in critically ill children, may enhance the acceptance, increase usage and aid in objective assessments.

PRACTICE IMPLICATIONS

These findings can be used to create a standardized protocol on implementing automated pupillometry in the PICU for critically ill children.

Impact of Bedside Echocardiography in the Management of Critically Ill Pediatric Patients in the Pediatric Intensive Care Unit: A Cross-Sectional Study

Background Managing critically ill pediatric patients is a challenging responsibility that necessitates effective prioritization and time management. It is important not only to assess the condition of the patient on a continuous and real-time basis but also to assess in a way that will provide vital clues that may help in diagnosis and treatment. Our study aims to investigate the association between echocardiography and clinical systemic examination, to find the association between cardiac dysfunction and pediatric outcomes, and to identify the indications and necessity of echocardiography assessments and therapeutic interventions for patients in the pediatric intensive care unit. Methods This cross-sectional study was conducted in the pediatric intensive care unit (PICU) of the pediatrics department at Datta Meghe Institute of Higher Education and Research, Wardha, India. All critically ill pediatric patients admitted to the PICU underwent echocardiography. The study primarily focused on the indications for echocardiography, the association between systolic and diastolic dysfunction and patient outcomes, and the therapeutic interventions implemented based on the echocardiographic findings.  Results The study analyzed 139 subjects aged from one month to 204 months, with the majority in the one- to five-year age group, followed by the 10-15-year age group. Cardiac anomalies were identified in 39 out of 139 cases, and cardiac murmurs were present in 27 cases with an almost equal gender distribution in the infantile age group. Dyspnea, edema, and hepatomegaly were the most common indications for echocardiography. Lasix was the most commonly used antifailure drug used in heart diseases. Sixteen individuals had systolic dysfunction, and eight had diastolic dysfunction, with a mortality rate of 62%. There was a significant association between systolic and diastolic dysfunction and mortality. Conclusion Echocardiography is a valuable asset within the PICU, providing critical insights into cardiac function and hemodynamics. By guiding clinical decision-making, it plays a pivotal role in optimizing care strategies, ultimately leading to improved outcomes for pediatric patients admitted with cardiac conditions. Overall, the study emphasizes the complex nature of pediatric cardiac conditions and the necessity for individualized treatment approaches based on distinct diagnoses and clinical indications.

Chassis-based fiber-coupled optical probe design for reproducible quantitative diffuse optical spectroscopy measurements

Advanced optical neuromonitoring of cerebral hemodynamics with hybrid diffuse optical spectroscopy (DOS) and diffuse correlation spectroscopy (DCS) methods holds promise for non-invasive characterization of brain health in critically ill patients. However, the methods' fiber-coupled patient interfaces (probes) are challenging to apply in emergent clinical scenarios that require rapid and reproducible attachment to the head. To address this challenge, we developed a novel chassis-based optical probe design for DOS/DCS measurements and validated its measurement accuracy and reproducibility against conventional, manually held measurements of cerebral hemodynamics in pediatric swine (n = 20). The chassis-based probe design comprises a detachable fiber housing which snaps into a 3D-printed, circumferential chassis piece that is secured to the skin. To validate its reproducibility, eight measurement repetitions of cerebral tissue blood flow index (BFI), oxygen saturation (StO2), and oxy-, deoxy- and total hemoglobin concentration were acquired at the same demarcated measurement location for each pig. The probe was detached after each measurement. Of the eight measurements, four were acquired by placing the probe into a secured chassis, and four were visually aligned and manually held. We compared the absolute value and intra-subject coefficient of variation (CV) of chassis versus manual measurements. No significant differences were observed in either absolute value or CV between chassis and manual measurements (p > 0.05). However, the CV for BFI (mean ± SD: manual, 19.5% ± 9.6; chassis, 19.0% ± 10.8) was significantly higher than StO2 (manual, 5.8% ± 6.7; chassis, 6.6% ± 7.1) regardless of measurement methodology (p<0.001). The chassis-based DOS/DCS probe design facilitated rapid probe attachment/re-attachment and demonstrated comparable accuracy and reproducibility to conventional, manual alignment. In the future, this design may be adapted for clinical applications to allow for non-invasive monitoring of cerebral health during pediatric critical care.

Long-term follow-up in pediatric intensive care-a narrative review

Pediatric intensive care is a rapidly developing medical specialty and with evolving understanding of pediatric pathophysiology and advances in technology, most children in the developed world are now surviving to intensive care and hospital discharge. As mortality rates for children with critical illness continue to improve, increasing PICU survivorship is resulting in significant long-term consequences of intensive care in these vulnerable patients. Although impairments in physical, psychosocial and cognitive function are well documented in the literature and the importance of establishing follow-up programs is acknowledged, no standardized or evidence-based approach to long-term follow-up in the PICU exists. This narrative review explores pediatric post-intensive care syndrome and summarizes the multifactorial deficits and morbidity that can occur in these patients following recovery from critical illness and subsequent discharge from hospital. Current practices around long-term follow-up are explored with discussion focusing on gaps in research and understanding with suggested ways forward and future directions.

Prospective evaluation of acute neurological events after paediatric cardiac surgery

OBJECTIVES

Children with CHD are at heightened risk of neurodevelopmental problems; however, the contribution of acute neurological events specifically linked to the perioperative period is unclear.

AIMS

This secondary analysis aimed to quantify the incidence of acute neurological events in a UK paediatric cardiac surgery population, identify risk factors, and assess how acute neurological events impacted the early post-operative pathway.

METHODS

Post-operative data were collected prospectively on 3090 consecutive cardiac surgeries between October 2015 and June 2017 in 5 centres. The primary outcome of analysis was acute neurological event, with secondary outcomes of 6-month survival and post-operative length of stay. Patient and procedure-related variables were described, and risk factors were statistically explored with logistic regression.

RESULTS

Incidence of acute neurological events after paediatric cardiac surgery in our population occurred in 66 of 3090 (2.1%) consecutive cardiac operations. 52 events occurred with other morbidities including renal failure (21), re-operation (20), cardiac arrest (20), and extracorporeal life support (18). Independent risk factors for occurrence of acute neurological events were CHD complexity 1.9 (1.1-3.2), p = 0.025, longer operation times 2.7 (1.6-4.8), p < 0.0001, and urgent surgery 3.4 (1.8-6.3), p < 0.0001. Unadjusted comparison found that acute neurological event was linked to prolonged post-operative hospital stay (median 35 versus 9 days) and poorer 6-month survival (OR 13.0, 95% CI 7.2-23.8).

CONCLUSION

Ascertainment of acute neurological events relates to local measurement policies and was rare in our population. The occurrence of acute neurological events remains a suitable post-operative metric to follow for quality assurance purposes.

Association of bilaterally suppressed EEG amplitudes and outcomes in critically ill children

Background and objectives

Amplitude-integrated EEG (aEEG) is used to assess electrocortical activity in pediatric intensive care if (continuous) full channel EEG is unavailable but evidence regarding the meaning of suppressed aEEG amplitudes in children remains limited. This retrospective cohort study investigated the association of suppressed aEEG amplitudes in critically ill children with death or decline of neurological functioning at hospital discharge.

Methods

Two hundred and thirty-five EEGs derived from individual patients <18 years in the pediatric intensive care unit at the University Hospital Essen (Germany) between 04/2014 and 07/2021, were converted into aEEGs and amplitudes analyzed with respect to age-specific percentiles. Crude and adjusted odds ratios (OR) for death, and functional decline at hospital discharge in patients with bilateral suppression of the upper or lower amplitude below the 10th percentile were calculated. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) were assessed.

Results

The median time from neurological insult to EEG recording was 2 days. PICU admission occurred due to neurological reasons in 43% and patients had high overall disease severity. Thirty-three (14%) patients died and 68 (29%) had a functional decline. Amplitude suppression was observed in 48% (upper amplitude) and 57% (lower amplitude), with unilateral suppression less frequent than bilateral suppression. Multivariable regression analyses yielded crude ORs between 4.61 and 14.29 and adjusted ORs between 2.55 and 8.87 for death and functional decline if upper or lower amplitudes were bilaterally suppressed. NPVs for bilaterally non-suppressed amplitudes were above 95% for death and above 83% for pediatric cerebral performance category Scale (PCPC) decline, whereas PPVs ranged between 22 and 32% for death and 49-52% for PCPC decline.

Discussion

This study found a high prevalence of suppressed aEEG amplitudes in critically ill children. Bilaterally normal amplitudes predicted good outcomes, whereas bilateral suppression was associated with increased odds for death and functional decline. aEEG assessment may serve as an element for risk stratification of PICU patients if conventional EEG is unavailable with excellent negative predictive abilities but requires additional information to identify patients at risk for poor outcomes.

Noninvasive Neuromonitoring Modalities in Children Part I: Pupillometry, Near-Infrared Spectroscopy, and Transcranial Doppler Ultrasonography

BACKGROUND

Noninvasive neuromonitoring in critically ill children includes multiple modalities that all intend to improve our understanding of acute and ongoing brain injury.

METHODS

In this article, we review basic methods and devices, applications in clinical care and research, and explore potential future directions for three noninvasive neuromonitoring modalities in the pediatric intensive care unit: automated pupillometry, near-infrared spectroscopy, and transcranial Doppler ultrasonography.

RESULTS

All three technologies are noninvasive, portable, and easily repeatable to allow for serial measurements and trending of data over time. However, a paucity of high-quality data supporting the clinical utility of any of these technologies in critically ill children is currently a major limitation to their widespread application in the pediatric intensive care unit.

CONCLUSIONS

Future prospective multicenter work addressing major knowledge gaps is necessary to advance the field of pediatric noninvasive neuromonitoring.

Pediatric Neurocritical Care: Maximizing Neurodevelopmental Outcomes Through Specialty Care

The field of pediatric neurocritical care (PNCC) has expanded and evolved over the last three decades. As mortality from pediatric critical care illness has declined, morbidity from neurodevelopmental disorders has expanded. PNCC clinicians have adopted a multidisciplinary approach to rapidly identify neurological injury, implement neuroprotective therapies, minimize secondary neurological insults, and establish transitions of care, all with the goal of improving neurocognitive outcomes for their patients. Although there are many aspects of PNCC and adult neurocritical care (NCC) medicine that are similar, elemental difference between adult and pediatric medicine has contributed to a divergent evolution of the respective fields. The low incidence of pediatric critical care illness, the heterogeneity of neurological insults, and the limited availability of resources all shape the need for a PNCC clinical care model that is distinct from the established paradigm adopted by the adult neurocritical care community at large. Considerations of neurodevelopment are fundamental in pediatrics. When neurological injury occurs in a child, the neurodevelopmental stage at the time of insult alters the impact of the neurological disease. Developmental variables contribute to a range of outcomes for seemingly similar injuries. Despite the relative infancy of the field of PNCC, early reports have shown that implementation of a specialized PNCC service elevates the quality and safety of care, promotes education and communication, and improves outcomes for children with acute neurological injuries. The multidisciplinary approach of PNCC clinicians and researchers also promotes a culture that emphasizes the importance of quality improvement and education initiatives, as well as development of and adherence to evidence-based guidelines and family-focused care models.

Neurological Pupillary Index (NPi) Measurement Using Pupillometry and Outcomes in Critically Ill Children

Aim/objective Neurological Pupil Index (NPi), measured by automated pupillometry (AP), allows the objective assessment of pupillary light reflex (PLR). NPi ranges from 0 (non-reactive) to 5 (normal). In this study, we aimed to compare neurologic and functional outcomes in children admitted for neurologic injury with normal (≥3) versus abnormal (<3) NPi measured during their pediatric intensive care unit (PICU) stay. Materials and methods We conducted a retrospective chart review of children between one month and 18 years admitted to our PICU with a diagnosis of neurologic injury between January 2019 and June 2022. We collected demographic, clinical, pupillometer, and outcome data, including mortality, Pediatric Cerebral Performance Category (PCPC), Pediatric Overall Performance Category (POPC), and Functional Status Score (FSS) at admission, at discharge, and at the three to six-month follow-up. We defined abnormal pupil response as any NPi <3 at any point during the PICU stay. Using the student's t-test and chi-square test, we compared the short-term and long-term outcomes of children with abnormal NPi (<3) versus those with normal NPi (≥3). Results There were 49 children who met the inclusion criteria and who had pupillometry data available for analysis. The mean (SD) Glasgow Coma Scale (GCS) in the study cohort was 5.6 (4.3), and 61% had low (<3) NPi during ICU stay. Mortality was significantly higher among patients with an abnormal NPi as compared to those with normal NPi. Children with abnormal NPi exhibited significant worsening of neurologic and functional status (ΔPCPC, ΔPOPC, and ΔFSS) from admission to discharge (mean (SD): 3.55(1.5), 3.45(1.43), 16.75(7.85), p<0.001) as compared to those with normal NPi (mean (SD): 1.45(0.93), 1.73(0.90), 3.55(2.07), p>0.05). The significant difference in neurologic and functional status persisted at the three to six-month follow-up between the two groups - children with abnormal NPi (mean (SD): 2.0(1.41), 2.08(1.38), 6.92(6.83), p<0.01) and children with normal NPi (mean (SD): 0.82(1.01), 0.94(1.03), 1.53(1.70), p>0.05). Conclusion In our retrospective cohort study, children admitted to the PICU for a neuro injury and with abnormal NPi (< 3) have higher mortality, and worse short-term and long-term neurologic and functional outcomes as compared to those with normal NPi (≥ 3) measured during the PICU course. AP provides an objective assessment of PLR and has potential applications for neuro-prognostication. More research needs to be done to elucidate the prognostic value of NPi in pediatrics.

Advanced Neuromonitoring Modalities on the Horizon: Detection and Management of Acute Brain Injury in Children

Timely detection and monitoring of acute brain injury in children is essential to mitigate causes of injury and prevent secondary insults. Increasing survival in critically ill children has emphasized the importance of neuroprotective management strategies for long-term quality of life. In emergent and critical care settings, traditional neuroimaging modalities, such as computed tomography and magnetic resonance imaging (MRI), remain frontline diagnostic techniques to detect acute brain injury. Although detection of structural and anatomical abnormalities remains crucial, advanced MRI sequences assessing functional alterations in cerebral physiology provide unique diagnostic utility. Head ultrasound has emerged as a portable neuroimaging modality for point-of-care diagnosis via assessments of anatomical and perfusion abnormalities. Application of electroencephalography and near-infrared spectroscopy provides the opportunity for real-time detection and goal-directed management of neurological abnormalities at the bedside. In this review, we describe recent technological advancements in these neurodiagnostic modalities and elaborate on their current and potential utility in the detection and management of acute brain injury.

[Pediatric neurocritical care]

Pediatric neurocritical care requires multidisciplinary expertise for the care of critically ill children. Approximately 14-16% of critically ill children in pediatric intensive care suffer from a primary neurological disease, whereby cardiac arrest and severe traumatic brain injury play major roles in Europe. The short-term goal of interventions in the pediatric intensive care unit is to stabilize vital functions, whereas the overarching goal is to achieve survival without neurological damage that enables fulfillment of the individual developmental physiological potential. For this reason, evidence-based methods for brain monitoring during the acute phase and recovery are necessary, which can be performed clinically or with technical devices. This applies to critically ill children with primary neurological diseases and for all children at risk for secondary neurological insults. Patients with diseases of the peripheral nervous system are also treated in pediatric intensive care medicine. In these patients, the primary aim frequently consists of bridging the time until recovery after acute deterioration, for example during an infection. In these patients, monitoring the cerebral function can be especially challenging, because due to the underlying disease the results of the examination cannot be interpreted in the same way as for previously neurologically healthy children. This article summarizes the complexity of pediatric neurocritical care by presenting examples of diagnostic and therapeutic approaches in the context of various neurological diseases that can be routinely encountered in the pediatric intensive care unit and can only be successfully treated by multidisciplinary teams.

Dynamic structures and emerging trends in the management of major trauma: A bibliometric analysis of publications between 2012 and 2021

Objective

Major trauma is currently a global public health issue with a massive impact on health at both the individual and population levels. However, there are limited bibliometric analyses on the management of major trauma. Thus, in this study we aimed to identify global research trends, dynamic structures, and scientific frontiers in the management of major trauma between 2012 and 2021.

Methods

We searched the Web of Science Core Collection to access articles and reviews concerning the management of major traumas and conducted a bibliometric analysis using CiteSpace.

Results

Overall, 2,585 studies were screened and published by 403 institutions from 110 countries/regions. The most productive country and institution in this field of research were the USA and Monash University, respectively. Rolf Lefering was the most prolific researcher and Holcomb JB had the most co-citations. Injury published the highest number of articles, and the Journal of Trauma was the most co-cited journal. A dual-map overlay of the literature showed that the articles of most publications were confined to the areas of medicine/medical/clinical and neurology/sports/ophthalmology. Document clustering indicated severe traumatic brain injury, traumatic coagulopathy, and resuscitative endovascular balloon occlusion as the recent hot topics. The most recent burst keywords were "trauma management," "neurocritical care," "injury severity," and "emergency medical services."

Conclusion

The dynamic structures and emerging trends in the management of major trauma were extensively analyzed using CiteSpace, a visualization software. Based on the analysis, the following research hotspots emerged: management of severe traumatic brain injury and massive hemorrhage, neurocritical care, injury severity, and emergency medical service. Our findings provide pertinent information for future research and contribute toward policy making in this field.

Transcranial Doppler Ultrasound, a Review for the Pediatric Intensivist

The use of transcranial Doppler ultrasound (TCD) is increasing in frequency in the pediatric intensive care unit. This review highlights some of the pertinent TCD applications for the pediatric intensivist, including evaluation of cerebral hemodynamics, autoregulation, non-invasive cerebral perfusion pressure/intracranial pressure estimation, vasospasm screening, and cerebral emboli detection.