Serum Biomarkers of Regeneration and Plasticity are Associated with Functional Outcome in Pediatric Neurocritical Illness: An Exploratory Study

Exploratory factor analysis yields grouping of brain injury biomarkers significantly associated with outcomes in neonatal and pediatric ECMO

In this two-center prospective cohort study of children on ECMO, we assessed a panel of plasma brain injury biomarkers using exploratory factor analysis (EFA) to evaluate their interplay and association with outcomes. Biomarker concentrations were measured daily for the first 3 days of ECMO support in 95 participants. Unfavorable composite outcome was defined as in-hospital mortality or discharge Pediatric Cerebral Performance Category > 2 with decline ≥ 1 point from baseline. EFA grouped 11 biomarkers into three factors. Factor 1 comprised markers of cellular brain injury (NSE, BDNF, GFAP, S100β, MCP1, VILIP-1, neurogranin); Factor 2 comprised markers related to vascular processes (vWF, PDGFRβ, NPTX1); and Factor 3 comprised the BDNF/MMP-9 cellular pathway. Multivariable logistic models demonstrated that higher Factor 1 and 2 scores were associated with higher odds of unfavorable outcome (adjusted OR 2.88 [1.61, 5.66] and 1.89 [1.12, 3.43], respectively). Conversely, higher Factor 3 scores were associated with lower odds of unfavorable outcome (adjusted OR 0.54 [0.31, 0.88]), which is biologically plausible given the role of BDNF in neuroplasticity. Application of EFA on plasma brain injury biomarkers in children on ECMO yielded grouping of biomarkers into three factors that were significantly associated with unfavorable outcome, suggesting future potential as prognostic instruments.

Brain-Derived Neurotrophic Factor in Pediatric Acquired Brain Injury and Recovery

We review emerging preclinical and clinical evidence regarding brain-derived neurotrophic factor (BDNF) protein, genotype, and DNA methylation (DNAm) as biomarkers of outcomes in three important etiologies of pediatric acquired brain injury (ABI), traumatic brain injury, global cerebral ischemia, and stroke. We also summarize evidence suggesting that BDNF is (1) involved in the biological embedding of the psychosocial environment, (2) responsive to rehabilitative therapies, and (3) potentially modifiable. BDNF's unique potential as a biomarker of neuroplasticity and neural repair that is reflective of and responsive to both pre- and post-injury environmental influences separates it from traditional protein biomarkers of structural brain injury with exciting potential to advance pediatric ABI management by increasing the accuracy of prognostic tools and informing clinical decision making through the monitoring of therapeutic effects.

Promoting Functional Recovery in Critically Ill Children

Over two-thirds of pediatric critical illness survivors will experience functional impairments that persist after discharge, that is, post-intensive care syndrome in pediatrics (PICS-p). Risk factors include child and family characteristics, invasive procedures, and social determinants of health. Approaches to remediate PICS-p include early rehabilitation, minimizing sedation, psychosocial resources for caregivers, delivery of family-centered care, and longitudinal screening for PICS-p. Challenges include feasible and validated approaches to screening, and resources and coordination for multidisciplinary care. Next steps should include resources to identify and address adverse social determinants of health and examination of treatment efficacy and implementation equity.

Association of EEG and Blood-Based Brain Injury Biomarker Accuracy to Prognosticate Mortality After Pediatric Cardiac Arrest: An Exploratory Study

BACKGROUND

Evaluate the accuracy of brain-based blood biomarkers neuron-specific enolase (NSE) and S100b and electroencephalography (EEG) features alone and in combination with prognosticate 6-month mortality after pediatric cardiac arrest. We hypothesized that the combination of blood brain-based biomarkers and EEG features would have superior classification accuracy of outcome versus either alone.

METHODS

Children (n = 58) aged between 1 week and 17 years admitted to the ICU following cardiac arrest at a tertiary care children's hopital were eligible for this secondary study. Blood NSE and S100b were measured closest to 24 hours after return of spontaneous circulation (ROSC). EEGs closest to 24 hours (median 11, interquartile range [IQR] 6 to 16 h) post-ROSC were evaluated by two epileptologists. EEG grade was informed by background frequency, amplitude, and continuity. Sleep spindles were present or absent. Mortality was assessed at six months post-ROSC. Area under the receiver operator curve (AUC) was performed for individual and combined brain-based biomarkers and EEG features.

RESULTS

Children were aged 2.6 (IQR 0.6 to 10.4) years, and 25 (43%) died. Children who died had increased blood NSE (49.7 [28.0 to 63.1] vs 18.2 [9.8 to 31.8] ng/mL) and S100b (0.118 [0.036 to 0.296] vs 0.012 [0.003 to 0.021] ng/mL) and poor (discontinuous or isoelectric) EEG grade (76% vs 33%) more frequently than survivors (P < 0.05). AUC for NSE to predict mortality was 0.789, and was 0.841 when combined with EEG grade and spindles. S100b AUC for mortality was 0.856 and was optimal alone.

CONCLUSIONS

In this exploratory study, the combination of brain-based biomarkers and EEG features may provide more accurate prognostication than either test alone after pediatric cardiac arrest.

Chronic critical illness and post-intensive care syndrome: from pathophysiology to clinical challenges

Background

Post‐intensive care syndrome (PICS) encompasses physical, cognition, and mental impairments persisting after intensive care unit (ICU) discharge. Ultimately it significantly impacts the long‐term prognosis, both in functional outcomes and survival. Thus, survivors often develop permanent disabilities, consume a lot of healthcare resources, and may experience prolonged suffering. This review aims to present the multiple facets of the PICS, decipher its underlying mechanisms, and highlight future research directions.

Main text

This review abridges the translational data underlying the multiple facets of chronic critical illness (CCI) and PICS. We focus first on ICU-acquired weakness, a syndrome characterized by impaired contractility, muscle wasting, and persisting muscle atrophy during the recovery phase, which involves anabolic resistance, impaired capacity of regeneration, mitochondrial dysfunction, and abnormalities in calcium homeostasis. Second, we discuss the clinical relevance of post-ICU cognitive impairment and neuropsychological disability, its association with delirium during the ICU stay, and the putative role of low-grade long-lasting inflammation. Third, we describe the profound and persistent qualitative and quantitative alteration of the innate and adaptive response. Fourth, we discuss the biological mechanisms of the progression from acute to chronic kidney injury, opening the field for renoprotective strategies. Fifth, we report long-lasting pulmonary consequences of ARDS and prolonged mechanical ventilation. Finally, we discuss several specificities in children, including the influence of the child’s pre-ICU condition, development, and maturation.

Conclusions

Recent understandings of the biological substratum of the PICS’ distinct features highlight the need to rethink our patient trajectories in the long term. A better knowledge of this syndrome and precipitating factors is necessary to develop protocols and strategies to alleviate the CCI and PICS and ultimately improve patient recovery.

Assessment of Patient Health-Related Quality of Life and Functional Outcomes in Pediatric Acute Respiratory Distress Syndrome

OBJECTIVES

To describe health-related quality of life (HRQL) and functional outcomes in pediatric acute respiratory distress syndrome (ARDS) and to determine risk factors associated with poor outcome defined as death or severe reduction in HRQL at 28 days or ICU discharge.

DESIGN

Prospective multisite cohort-outcome study conducted between 2019 and 2020.

SETTING

Eight academic PICUs in the United States.

PATIENTS

Children with ARDS based on standard criteria.

INTERVENTIONS

Patient characteristics and illness severity were collected during PICU admission. Parent proxy-report measurements were obtained at baseline, day 28/ICU discharge, month 3, and month 9, utilizing Pediatric Quality of Life Inventory and Functional Status Scale (FSS). A composite outcome evaluated using univariate and multivariate analysis was death or severe reduction in HRQL (>25% reduction in the Pediatric Quality of Life Inventory at day 28/ICU discharge.

MEASUREMENTS AND MAIN RESULTS

This study enrolled 122 patients with a median age of 3 years (interquartile range, 1-12 yr). Common etiologies of ARDS included pneumonia ( n = 63; 52%) and sepsis ( n = 27; 22%). At day 28/ICU discharge, half (50/95; 53%) of surviving patients with follow-up data reported a greater than 10% decrease in HRQL from baseline, and approximately one-third of participants ( n = 19/61; 31%) reported a greater than 10% decrease in HRQL at 9 months. Trends in FSS were similar. Of 104 patients with data, 47 patients (45%) died or reported a severe decrease of greater than 25% in HRQL at day 28/ICU discharge. Older age was associated with an increased risk of death or severe reduction in HRQL (odds ratio, 1.08; CI, 1.01-1.16).

CONCLUSIONS

Children with ARDS are at risk for deterioration in HRQL and FSS that persists up to 9 months after ARDS. Almost half of children with ARDS experience a poor outcome including death or severe reduction in HRQL at day 28/ICU discharge.

Risk Factors for Physical Function Impairments in Postintensive Care Syndrome: A Scoping Review

OBJECTIVE

Survivors of critical illness may experience short- and long-term physical function impairments. This review aimed to identify the risk factors for physical function impairments from the current literature.

DATA SOURCES

A systematic search of the PubMed, Embase, Web of Science, and Cochrane Library databases following the Preferred Reporting Items for Systematic Reviews and Meta-analyses extension for Scoping Reviews guideline was performed.

STUDY SELECTION

The risk factors reported in all human studies reporting physical function impairments in children admitted to the pediatric intensive care unit (PICU) were reviewed and categorized. Two investigators independently screened, evaluated, and selected studies for inclusion. Data from eligible studies were extracted by one investigator, and another investigator reviewed and verified the data. A systematic narrative approach was employed to review and summarize the data.

RESULTS

A total of 264 studies were found to be eligible, with 19 studies meeting the inclusion criteria. Children admitted to the PICU experienced physical function impairments during their stay, which can last for years. The studies varied primarily in the measurement timing and tools used. The most frequently reported risk factors for physical function impairments were age, race or ethnicity, a pre-admission chronic condition, sex, disease severity, duration or the presence of mechanical ventilation, and admission diagnosis.

CONCLUSIONS

Physical function impairments may be persistent in PICU survivors. To prevent these impairments in critically ill patients, pediatricians should pay attention to modifiable risk factors, such as the duration of mechanical ventilation. Future studies need to promote a combination of standardized measures for the detection and prevention of physical function impairments.