Association between Exposure of Young Children to Procedures Requiring General Anesthesia and Learning and Behavioral Outcomes in a Population-based Birth Cohort. Anesthesiology. 2017;127:227-240. [PMID: 28609302 DOI: 10.1097/aln.0000000000001735]

The Influence of Patient-Centered Communication on Children's Anxiety and Use of Anesthesia for MR

Background: The aim of this study was to inspect the influence of patient-centered communication (PCC) with 4- to 10-year-old children on the use of anesthesia for magnetic resonance imaging exams (MRs). Methods: A total of thirty children received the PCC and pre-simulated the exam with an MR toy. Another 30 children received routine information about the MR and pre-simulated the exam with the toy. Anesthesia use in these two groups was additionally compared with a previously existing group of children (n = 30) who had received only routine information about the exam (CG). Children’s anxiety was assessed with a self-report question plus heartbeat frequency. Children’s satisfaction was assessed through several questions. The analyses were based on group comparisons and regression. Results: A total of two children (7%) in the PCC + simulation group used sedation compared with 14 (47%) in the simulation group and 21 (70%) in the CG. Differences between the PCC + simulation and the other two groups were significant (p < 0.001), although not between the simulation and the CG. The decrease in anxiety was significantly greater (self-reported p < 0.001; heart rate p < 0.05) and satisfaction was higher (p = 0.001) in the PCC + simulation, when compared with the simulation group. Reduced anxiety was associated with less anesthesia use (OR 1.39; CI 1.07−1.79; p = 0.013). Conclusions: PCC + simulation was more effective than simulation and routine practice in decreasing children’s anxiety, increasing satisfaction, and reducing the use of anesthesia for MRs.

The risk of autism spectrum disorder and intellectual disability but not attention deficit/hyperactivity disorder is increased in individuals with esophageal atresia

Knowledge of neurodevelopmental disorders such as attention deficit/hyperactivity disorder (ADHD), autism spectrum disorders (ASD) and intellectual disability (ID) in patients with esophageal atresia (EA) is scarce. The aims of this study were to investigate the prevalence and risk of ADHD, ASD and ID in individuals with EA. Data were obtained from four longitudinal population-based registries in Sweden and analyzed using Cox proportional hazards regression. Patients with EA born in Sweden in 1973-2018 were included together with five controls for each individual with the exposure matched on sex, gestational age at birth, birth year and birth county. Individuals with chromosomal aberrations and syndromes were excluded. In total, 735 individuals with EA and 3675 controls were included. Median age at time of the study was 20 years (3-48). ASD was found in 24 (3.9%), ADHD in 34 (5.5%) and ID in 28 (4.6%) individuals with EA. Patients with EA had a 1.66 times higher risk of ASD (95% confidence interval [CI], 1.05-2.64) and a 3.62 times higher risk of ID (95% CI, 2.23-5.89) compared with controls. The risk of ADHD was not significantly increased. ADHD medication had been prescribed to 88.2% of patients with EA and ADHD and to 84.5% of controls with ADHD. Individuals with EA have a higher risk of ASD and ID than individuals without the exposure. These results are important when establishing follow-up programs for children with EA to allow timely detection and consequentially an earlier treatment and support especially before school start.

Neonatal exposures to sevoflurane in rhesus monkeys alter synaptic ultrastructure in later life

Repeated or prolonged early life exposure to anesthesia is neurotoxic in animals and associated with neurocognitive impairment in later life in humans. We used electron microscopy with unbiased stereological sampling to assess synaptic ultrastructure in dorsolateral prefrontal cortex (dlPFC) and hippocampal CA1 of female and male rhesus monkeys, four years after three 4-h exposures to sevoflurane during the first five postnatal weeks. This allowed us to ascertain long-term consequences of anesthesia exposure without confounding effects of surgery or illness. Synapse areas were reduced in the largest synapses in CA1 and dlPFC, predominantly in perforated spinous synapses in CA1 and nonperforated spinous synapses in dlPFC. Mitochondrial morphology and localization changed subtly in both areas. Synapse areas in CA1 correlated with response to a mild social stressor. Thus, exposure to anesthesia in infancy can cause long-term ultrastructural changes in primates, which may be substrates for long-term alterations in synaptic transmission and behavioral deficits.

Systemic inflammation exacerbates developmental neurotoxicity induced by sevoflurane in neonatal rats

BACKGROUND

General anaesthesia in the neonatal period has detrimental effects on the developing mammalian brain. The impact of underlying inflammation on anaesthesia-induced developmental neurotoxicity remains largely unknown.

METHODS

Postnatal day 7 (PND7) rats were randomly assigned to receive sevoflurane (3 vol% for 3 h) or carrier gas 12 h after bacterial lipopolysaccharide (LPS; 1 μg g-1) or vehicle injection. Pharmacological inhibition of caspase-1 by Vx-765 (two doses of 50 μg g-1 body weight) was used to investigate mechanistic pathways of neuronal injury. Histomorphological injury and molecular changes were quantified 2 h after the end of anaesthesia. Long-term functional deficits were tested at 5-8 weeks of age using a battery of behavioural tests in the memory and anxiety domains.

RESULTS

Sevoflurane or LPS treatment increased activated caspase-3 and caspase-9 expression in the hippocampal subiculum and CA1, which was greater when sevoflurane was administered in the setting of LPS-induced inflammation. Neuronal injury induced by LPS+sevoflurane treatment resulted in sex-specific behavioural outcomes when rats were tested at 5-8 weeks of age, including learning and memory deficits in males and heightened anxiety-related behaviour in females. Hippocampal caspase-1 and NLRP1 (NLR family pyrin domain containing 1), but not NLRP3, were upregulated by LPS or LPS+sevoflurane treatment, along with related proinflammatory cytokines, interleukin (IL)-1β, and IL-18. Pretreatment with Vx-765, a selective caspase-1 inhibitor, led to reduced IL-1β in LPS and LPS+sevoflurane groups. Caspase-1 inhibition by Vx-765 significantly decreased activated caspase-3 and caspase-9 immunoreactivity in the subiculum.

CONCLUSIONS

Systemic inflammation promotes developmental neurotoxicity by worsening anaesthesia-induced neuronal damage with sex-specific behavioural outcomes. This highlights the importance of studying anaesthesia-induced neurotoxicity in more clinically relevant settings.

Sedation Practices for Lumbar Punctures in Patients With Acute Lymphoblastic Leukemia: A Multicenter Retrospective Study Using Pediatric Health Information Systems

BACKGROUND

Sedation is often used to reduce pain and anxiety in pediatric patients with acute lymphoblastic leukemia (ALL) undergoing lumbar punctures (LPs). There is a potential for long-term effects on neurocognition with repeat sedative exposures in young children. The purpose of this study is to determine the practice habits regarding sedation for LPs in pediatric patients with ALL among multiple institutions.

METHODS

This is a retrospective study of 48 hospitals in the Pediatric Health Information Systems (PHIS) between October 2015 and December 2019. Children 1 to 18 years old with ALL who received intrathecal chemotherapy in an outpatient setting were included. We analyzed the prevalence of anesthesia usage and the types of anesthetics used.

RESULTS

Of the 16,785 encounters with documented use of anesthetic medications, intravenous and inhaled anesthetics were used in 16,486 (98.2%) and local anesthetics alone in 299 (1.8%). The most commonly used medications used for sedation were propofol (n=13,279; 79.1%), midazolam (n=4228; 25.2%), inhaled fluranes (n=3169; 18.9%), and ketamine (n=2100; 12.5%).

CONCLUSION

The majority of children's hospitals in the United States use intravenous and inhaled anesthetics for routine therapeutic LPs in pediatric patients with ALL. Propofol is one of the most common medications used for sedation.

General anesthesia in children and long-term neurodevelopmental deficits: A systematic review

Background

Millions of children experienced surgery procedures requiring general anesthesia (GA). Any potential neurodevelopmental risks of pediatric anesthesia can be a serious public health issue. Various animal studies have provided evidence that commonly used GA induced a variety of morphofunctional alterations in the developing brain of juvenile animals.

Methods

We conducted a systematic review to provide a brief overview of preclinical studies and summarize the existing clinical studies. Comprehensive literature searches of PubMed, EMBASE, CINAHL, OVID Medline, Web of Science, and the Cochrane Library were conducted using the relevant search terms “general anesthesia,” “neurocognitive outcome,” and “children.” We included studies investigating children who were exposed to single or multiple GA before 18, with long-term neurodevelopment outcomes evaluated after the exposure(s).

Results

Seventy-two clinical studies originating from 18 different countries published from 2000 to 2022 are included in this review, most of which are retrospective studies (n = 58). Two-thirds of studies (n = 48) provide evidence of negative neurocognitive effects after GA exposure in children. Neurodevelopmental outcomes are categorized into six domains: academics/achievement, cognition, development/behavior, diagnosis, brain studies, and others. Most studies focusing on children &lt;7 years detected adverse neurocognitive effects following GA exposure, but not all studies consistently supported the prevailing view that younger children were at greater risk than senior ones. More times and longer duration of exposures to GA, and major surgeries may indicate a higher risk of negative outcomes.

Conclusion

Based on current studies, it is necessary to endeavor to limit the duration and numbers of anesthesia and the dose of anesthetic agents. For future studies, we require cohort studies with rich sources of data and appropriate outcome measures, and carefully designed and adequately powered clinical trials testing plausible interventions in relevant patient populations.

The role of depolarizing activation of Na+-Ca2+ exchanger by oligodendrocyte progenitor cells in the effect of sevoflurane on myelination

AIMS

The aim of this study was to investigate the role of depolarizing activation of Na⁺-Ca²⁺ exchanger (NCX) by oligodendrocyte progenitor cells (OPC) in the effect of sevoflurane on myelination.

MAIN METHODS

On postnatal days 7, 8, and 9, mice were exposed to 3 % sevoflurane for 2 h per day. The proliferation, differentiation, and myelin sheath of OPC were observed with immunofluorescence, quantitative real-time polymerase chain reaction (QRT-PCR), and transmission electron microscopy (TEM) at various time points. The open field, Y maze, and new object recognition tests were used to measure spatial learning and memory. siRNA was used for the knockdown NCX1 in human OPC (HOPC) before sevoflurane exposure; the Transwell migration assay was used to measure cell migration ability and Fluo 4-AM was used to measure intracellular Ca2+ concentration.

KEY FINDINGS

Pretreatment with an NCX inhibitor attenuated the proliferation and differentiation of OPC induced by sevoflurane and induced a remarkable increase in platelet-derived growth factor receptor-alpha (PDGFRα), 2, 3-cyclic nucleotide 3-phosphodiesterase (CNPase), oligodendrocyte transcription factor 2 (Olig2), and homeodomain protein NK2 homeobox 2 (NKX2.2) levels. Pretreatment with an NCX inhibitor alleviated the sevoflurane-induced myelination disorder and cognitive impairment. The decreased cell migration and increased intracellular Ca²⁺ concentration observed in the siRNA-negative control group was reversed in the sevoflurane plus siRNA-NCX1 group.

SIGNIFICANCE

This study suggests that repeated sevoflurane exposure in newborn mice leads to depolarization of OPC, which leads to Ca²⁺ influx through NCX and affects OPC proliferation, migration, differentiation, and myelination, ultimately leading to cognitive impairment.

The impact of early exposure to general anesthesia on visual and neurocognitive development

Every year millions of children are exposed to general anesthesia while undergoing surgical and diagnostic procedures. In the field of ophthalmology, 44,000 children are exposed to general anesthesia annually for strabismus surgery alone. While it is clear that general anesthesia is necessary for sedation and pain minimization during surgical procedures, the possibility of neurotoxic impairments from its exposure is of concern. In animals there is strong evidence linking early anesthesia exposure to abnormal neural development. but in humans the effects of anesthesia are debated. In humans many aspects of vision develop within the first year of life, making the visual system vulnerable to early adverse experiences and potentially vulnerable to early exposure to general anesthesia. We attempt to address whether the visual system is affected by early postnatal exposure to general anesthesia. We first summarize key mechanisms that could account for the neurotoxic effects of general anesthesia on the developing brain and review existing literature on the effects of early anesthesia exposure on the visual system in both animals and humans and on neurocognitive development in humans. Finally, we conclude by proposing future directions for research that could address unanswered questions regarding the impact of general anesthesia on visual development.

Novel anesthetics in pediatric practice: is it time?

PURPOSE OF REVIEW

Steadily mounting evidence of anesthesia-induced developmental neurotoxicity has been a challenge in pediatric anesthesiology. Considering that presently used anesthetics have, in different animal models, been shown to cause lasting behavioral impairments when administered at the peak of brain development, the nagging question, 'Is it time for the development of a new anesthetic' must be pondered.

RECENT FINDINGS

The emerging 'soft analogs' of intravenous anesthetics aim to overcome the shortcomings of currently available clinical drugs. Remimazolam, a novel ester-analog of midazolam, is a well tolerated intravenous drug with beneficial pharmacological properties. Two novel etomidate analogs currently in development are causing less adrenocortical suppression while maintaining equally favorable hemodynamic stability and rapid metabolism. Quaternary lidocaine derivatives are explored as more potent and longer lasting alternatives to currently available local anesthetics. Xenon, a noble gas with anesthetic properties, is being considered as an anesthetic-sparing adjuvant in pediatric population. Finally, alphaxalone is being reevaluated in a new drug formulation because of its favorable pharmacological properties.

SUMMARY

Although a number of exciting anesthetic drugs are under development, there is currently no clear evidence to suggest their lack of neurotoxic properties in young brain. Well designed preclinical studies are needed to evaluate their neurotoxic potential.

Long-term cognitive and behavioral outcomes following early exposure to general anesthetics

PURPOSE OF REVIEW

Nearly 100 clinical studies have been published evaluating neurodevelopmental outcomes in children following surgery and anesthesia. These studies have reported mixed results, likely attributable at least in part to significant heterogeneity in their study designs, types and numbers of exposures, patient populations evaluated, and most importantly, the outcomes that were assessed. This review aims to summarize the results from clinical studies evaluating behavioral outcomes in children exposed to surgery and anesthesia.

RECENT FINDINGS

Children with early exposure to surgery and anesthesia were found to have limited to no differences in intelligence when compared with unexposed children. However, several studies have reported more behavioral problems in children exposed to general anesthesia. An increased incidence of attention-deficit hyperactivity disorder has also been reported in anesthetic exposed children, particularly after multiple exposures.

SUMMARY

Nearly all clinical studies of anesthetic neurotoxicity are observational in nature, so the associations between anesthetic exposure and behavioral deficits cannot yet be directly attributed to the anesthetic medication. However, the finding of deficits in some neurodevelopmental domains and not others will help guide the selection of appropriate outcomes in future studies of anesthetic neurotoxicity that can further evaluate whether anesthetic medications have an impact on neurodevelopment in children.

Sevoflurane Exposure in the Developing Brain Induces Hyperactivity, Anxiety-Free, and Enhancement of Memory Consolidation in Mice

Background

Sevoflurane exposure at brain developmental stages has been reported to induce neurotoxicity and, subsequently, results in learning deficits at the juvenile age. In this study, we aimed to investigate the effects of prior early-age sevoflurane exposure on locomotor activity, anxiety, CA1-dependent learning, and spatial memory, as well as synapse changes in mice.

Methods

Totally, 3% sevoflurane was given to neonatal mice at postnatal day 7 for 4 h. These sevoflurane-treated mice were later subjected to open field and Morris water maze tests at their adult age (postnatal days 60–90) to assess their motor activity and spatial learning ability, respectively. The brain slices of sevoflurane-treated and control mice were examined for dendritic spine density and long-term potentiation (LTP) features following behavior tests (postnatal day 60). Protein levels of N-methyl-D-aspartate (NMDA) receptor subtypes and PSD95 in brain lysate were measured by using immunoblotting at the same age (postnatal day 60).

Results

Prior early-age sevoflurane exposure increased the overall moving distance, prolonged the central-area lingering time, and increased the central-area entries of adult mice. Sevoflurane-treated mice spent more time in the target quadrant during the probe test. An increase of the spine density of pyramidal neurons in the CA1 region was observed in sevoflurane-treated mice. NMDA receptor GluN2A subunit, but not the GluN2B or PSD95, was increased in the brain lysate of sevoflurane-treated mice compared with that of control mice. LTP in the hippocampus did not significantly differ between sevoflurane-treated and control mice.

Conclusion

Exposure to sevoflurane for mice during an early brain developmental stage (P7) induces later-on hyperactivity, anxiety-free, and enhancement of memory retention. These observations shed light on future investigations on the underlying mechanisms of sevoflurane’s effect on neuronal development.

Functional MRI Changes in Patients after Thyroidectomy under General Anesthesia

Cognitive changes affecting elderly patients following surgery under anesthesia have drawn significant attention and have been investigated in considerable depth. Resting-state functional magnetic resonance imaging (rs-fMRI) can be used to assess changes in brain functional connectivity (FC) associated with postoperative changes in cognition, a common complication in seniors undergoing surgery. In this study, we recruited 20 patients over 55 of age and scheduled an elective thyroidectomy under general anesthesia to assess perioperative changes in brain FC density (FCD) in patients undergoing thyroidectomy under general anesthesia using rs-fMRI. All 20 patients underwent a series of clinical, quantitative, neurological, and neuropsychological tests and fMRI examinations on the day before surgery (Day 0) and 7 days after surgery (Day 7). The following tests were conducted on all patients: the Minimental State Examination (MMSE), the digit symbol substitution test (DSST), the trail making test (part A), the verbal fluency test, and Warrington's recognition memory test (WRMT). FMRI data were acquired using a 3T MR system; the FCD values were calculated using the REST software package. We used paired t-tests to compare the FCD between Day 7 and Day 0. A value of p < 0.05 was considered to reflect statistical significance. The postoperative FCD was significantly reduced in the supplementary motor area (SMA). Analyses of the percentage changes of errors in the WRMT revealed a significant and negative correlation with the mean percentage change of FCD in the SMA (Spearman's r = −0.54, 95% CI: (-0.80, -0.12), p = 0.014). Postoperative changes in FCD in the SMA may be associated with the perioperative neurocognitive changes in patients undergoing partial thyroidectomy under general anesthesia.

Safety of general anaesthetics on the developing brain: are we there yet?

Thirty years ago, neurotoxicity induced by general anaesthetics in the developing brain of rodents was observed. In both laboratory-based and clinical studies, many conflicting results have been published over the years, with initial data confirming both histopathological and neurodevelopmental deleterious effects after exposure to general anaesthetics. In more recent years, animal studies using non-human primates and new human cohorts have identified some specific deleterious effects on neurocognition. A clearer pattern of neurotoxicity seems connected to exposure to repeated general anaesthesia. The biochemistry involved in this neurotoxicity has been explored, showing differential effects of anaesthetic drugs between the developing and developed brains. In this narrative review, we start with a comprehensive description of the initial concerning results that led to recommend that any non-essential surgery should be postponed after the age of 3 yr and that research into this subject should be stepped up. We then focus on the neurophysiology of the developing brain under general anaesthesia, explore the biochemistry of the observed neurotoxicity, before summarising the main scientific and clinical reports investigating this issue. We finally discuss the GAS trial, the importance of its results, and some potential limitations that should not undermine their clinical relevance. We finally suggest some key points that could be shared with parents, and a potential research path to investigate the biochemical effects of general anaesthesia, opening up perspectives to understand the neurocognitive effects of repetitive exposures, especially in at-risk children.

Nonapoptotic caspases in neural development and in anesthesia-induced neurotoxicity

Apoptosis, classically initiated by caspase pathway activation, plays a prominent role during normal brain development as well as in neurodegeneration. The noncanonical, nonlethal arm of the caspase pathway is evolutionarily conserved and has also been implicated in both processes, yet is relatively understudied. Dysregulated pathway activation during critical periods of neurodevelopment due to environmental neurotoxins or exposure to compounds such as anesthetics can have detrimental consequences for brain maturation and long-term effects on behavior. In this review, we discuss key molecular characteristics and roles of the noncanonical caspase pathway and how its dysregulation may adversely affect brain development. We highlight both genetic and environmental factors that regulate apoptotic and sublethal caspase responses and discuss potential interventions that target the noncanonical caspase pathway for developmental brain injuries.

Anesthetic Exposure During Childhood and Neurodevelopmental Outcomes: A Systematic Review and Meta-analysis

Importance

Clinical studies of neurodevelopmental outcomes after anesthetic exposure have evaluated a range of outcomes with mixed results.

Objective

To examine via meta-analyses the associations between exposure to general anesthesia and domain-specific neurodevelopmental outcomes in children.

Data Sources

PubMed/MEDLINE, Embase, CINAHL, Web of Science and the Cochrane Library were searched from inception to August 31, 2021.

Study Selection

Inclusion criteria were exposures to procedures requiring general anesthesia at younger than 18 years and evaluation of long-term neurodevelopmental function after exposure. Studies lacking unexposed controls or focused on children with major underlying comorbidities were excluded.

Data Extraction and Synthesis

Extracted variables included effect size; hazard, risk, or odds ratio; number of exposures; procedure type; major comorbidities; age of exposure and assessment; presence of unexposed controls; and study design. Studies were independently reviewed by 2 coders, and review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Data were pooled using a random-effects model.

Main Outcomes and Measures

The main outcomes were standardized mean differences (SMD) for scores in the neurodevelopmental domains of academics, behavioral problems, cognition, executive function, general development, language, motor function, nonverbal reasoning, social cognition, and hazard and risk of neurodevelopmental disorder diagnoses.

Results

A total of 31 studies contributed data for meta-analysis. For each of the assessed neurodevelopmental domains, the numbers of children evaluated ranged from 571 to 63 315 exposed and 802 to 311 610 unexposed. Children with any exposure (single or multiple) had significantly worse behavioral problems scores, indicating more behavioral problems (SMD, -0.10; 95% CI, -0.18 to -0.02; P = .02), and worse scores in academics (SMD, -0.07; 95% CI -0.12 to -0.01; P = .02), cognition (SMD, -0.03; 95% CI, -0.05 to 0.00; P = .03), executive function (SMD, -0.20; 95% CI, -0.32 to -0.09; P < .001), general development (SMD, -0.08; 95% CI, -0.13 to -0.02; P = .01), language (SMD, -0.08; 95% CI, -0.14 to -0.02; P = .01), motor function (SMD, -0.11; 95% CI, -0.21 to -0.02; P = .02), and nonverbal reasoning (SMD, -0.15; 95% CI, -0.27 to -0.02; P = .02). Higher incidences of neurodevelopmental disorder diagnoses were also reported (hazard ratio, 1.19; 95% CI, 1.09 to 1.30; P < .001; risk ratio, 1.81; 95% CI, 1.25 to 2.61; P = .002).

Conclusions and Relevance

These findings support the hypothesis that associations between anesthetic exposure during childhood and subsequent neurodevelopmental deficits differ based on neurodevelopmental domain.

Effect of Anesthesia on Oligodendrocyte Development in the Brain

Oligodendrocytes (OLs) participate in the formation of myelin, promoting the propagation of action potentials, and disruption of their proliferation and differentiation leads to central nervous system (CNS) damage. As surgical techniques have advanced, there is an increasing number of children who undergo multiple procedures early in life, and recent experiments have demonstrated effects on brain development after a single or multiple anesthetics. An increasing number of clinical studies showing the effects of anesthetic drugs on the development of the nervous system may mainly reside in the connections between neurons, where myelin development will receive more research attention. In this article, we review the relationship between anesthesia exposure and the brain and OLs, provide new insights into the development of the relationship between anesthesia exposure and OLs, and provide a theoretical basis for clinical prevention of neurodevelopmental risks of general anesthesia drugs.

Does Resveratrol Prevent Sevoflurane Toxicity in Newborn Rats?

Inhalation anesthetics have been shown to cause neurodevelopmental disorders and neurotoxic effects. In this study, we aimed to investigate the effect of resveratrol on the possible neurotoxic effect of sevoflurane and the brain-derived neurotrophic factor (BDNF) pathway in newborn rats. The animals were divided into four groups: control, sevoflurane, sevoflurane+resveratrol 25 mg/kg, and sevoflurane+resveratrol 50 mg/kg. The groups that received anesthesia were given 3% sevoflurane for 2 h on the postnatal seventh, eighth, and ninth days. Control gas was applied to the control group. The Morris water maze (MWM) test was performed on postnatal 35th day. After performing the open field test on the postnatal 41st day, the animals were dissected, and the hippocampal BDNF levels were determined by Western blot method. In the MWM test, there was a significant decrease in the time spent in the target quadrant in the sevoflurane anesthesia group compared with control group. This reduction was reversed with the resveratrol pretreatment. Sevoflurane exposure significantly decreased hippocampal BDNF levels compared with the control group. The resveratrol 25 mg/kg pretreatment did not reverse this reduction, whereas resveratrol 50 mg/kg ameliorated this impairment. Sevoflurane did not cause any significant difference in the rats' performance in the open field test. However, 50 mg/kg resveratrol pretreatment caused a statistically significant increase in this performance. Our results showed that sevoflurane impaired learning and memory functions in newborn rats and resveratrol reversed this deterioration. Also BDNF might play a role in this beneficial effect of resveratrol.

Long Term Neurodevelopmental Outcomes after Sevoflurane Neonatal Exposure of Extremely Preterm Children: A Cross-Sectional Observationnal Study

Sevoflurane, a volatile anesthetic, is used when extremely preterm neonates (EPT) undergo painful procedures. Currently, no existing studies analyze sevoflurane’s long-term effects during the EPT’s immediate neonatal period. Our primary objective was to compare the EPT’s neurocognitive development regardless of any sevoflurane exposure prior to 45 weeks corrected gestational age (GA). We analyzed those live discharges, less than 28 weeks GA, who were either exposed, unexposed, and/or multiply exposed to sevoflurane before 45 weeks GA. All data were obtained from a cross-sectional multicenter study (GPQoL study, NCT01675726). Children, both exposed and non-exposed to sevoflurane, were sampled using a propensity-guided approach. Neurological examinations (Touwen), cognitive and executive functions (WISC IV, NEPSY, Rey figure), and assessments when the children were between 7 and 10 years old, were correlated to their neonatal sevoflurane exposure. There were 139 children in the study. The mean gestational age was 26.2 weeks (±0.8) GA and the mean birth weight was 898 g (±173). The mean age of their evaluation was 8.47 years old (±0.70). Exposure to sevoflurane to the mean corrected age 27.10 (3.37) weeks GA had a significant correlation with cerebral palsy (adjusted odds ratio (aOR): 6.70 (CI 95%: 1.84–32.11)) and other major disorders (cerebral palsy and/or severe cognitive retardation) (aOR: 2.81 [95% CI: 1.13–7.35]). Our results demonstrate the possibility of long-term effects on EPT infants who had a sevoflurane exposure before 45 weeks corrected GA. However, these results will require further confirmation by randomized controlled trials.

Percutaneous Closure of Patent Ductus Arteriosus

Percutaneous-based patent ductus arteriosus closure is technically feasible among infants less than 1.5 kg. However, marked heterogeneity in the type and nature of adverse events obscures current safety profile assessments. Although data on the risks of postdevice closure syndrome remain promising, a lack of comparative trials of surgical ductal ligation and inconsistent surveillance across published studies obscure confidence in present estimates of safety and efficacy. To minimize risk and yield the greatest benefits, clinical studies of patent ductus arteriosus treatment should consider incorporating more robust assessments to ensure that infants at greatest risk for adverse ductal consequences are included.

Association of Acute Respiratory Failure in Early Childhood With Long-term Neurocognitive Outcomes

IMPORTANCE

Approximately 23 700 US children undergo invasive mechanical ventilation for acute respiratory failure annually, with unknown long-term effects on neurocognitive function.

OBJECTIVE

To evaluate neurocognitive outcomes of children who survive pediatric intensive care unit (PICU) hospitalization for acute respiratory failure compared with their biological siblings.

DESIGN, SETTING, AND PARTICIPANTS

Prospective sibling-matched cohort study conducted at 31 US PICUs and associated neuropsychology testing centers. Patients were 8 years or younger with a Pediatric Cerebral Performance Category score of 1 (normal) before PICU admission and less than or equal to 3 (no worse than moderate neurocognitive dysfunction) at PICU discharge, excluding patients with a history of neurocognitive deficits or who were readmitted and underwent mechanical ventilation. Biological siblings were aged 4 to 16 years at testing, with Pediatric Cerebral Performance Category score of 1 and no history of mechanical ventilation or general anesthesia. A total of 121 sibling pairs were enrolled from September 2, 2014, to December 13, 2017, and underwent neurocognitive testing starting March 14, 2015. The date of the final follow-up was November 6, 2018.

EXPOSURES

Critical illness and PICU treatment for acute respiratory failure.

MAIN OUTCOMES AND MEASURES

The primary outcome was IQ, estimated by the age-appropriate Vocabulary and Block Design subtests of the Wechsler Intelligence Scale. Secondary outcomes included measures of attention, processing speed, learning and memory, visuospatial skills, motor skills, language, and executive function. Evaluations occurred 3 to 8 years after hospital discharge.

RESULTS

Patients (n = 121; 55 [45%] female patients) underwent PICU care at a median (IQR) age of 1.0 (0.2-3.2) years, received a median (IQR) of 5.5 (3.1-7.7) days of invasive mechanical ventilation, and were tested at a median (IQR) age of 6.6 (5.4-9.1) years. Matched siblings (n = 121; 72 [60%] female siblings) were tested at a median (IQR) age of 8.4 (7.0-10.2) years. Patients had a lower mean estimated IQ than matched siblings (101.5 vs 104.3; mean difference, -2.8 [95% CI, -5.4 to -0.2]). Among secondary outcomes, patients had significantly lower scores than matched siblings on nonverbal memory (mean difference, -0.9 [95% CI, -1.6 to -0.3]), visuospatial skills (mean difference, -0.9 [95% CI, -1.8 to -0.1]), and fine motor control (mean difference, -3.1 [95% CI, -4.9 to -1.4]) and significantly higher scores on processing speed (mean difference, 4.4 [95% CI, 0.2-8.5]). There were no significant differences in the remaining secondary outcomes, including attention, verbal memory, expressive language, and executive function.

CONCLUSIONS AND RELEVANCE

Among children, survival of PICU hospitalization for respiratory failure and discharge without severe cognitive dysfunction was associated with significantly lower subsequent IQ scores compared with matched siblings. However, the magnitude of the difference was small and of uncertain clinical importance.

Evolution of Early Onset Scoliosis under Treatment with a 3D-Brace Concept

The objective of this study is to examine the evolution of all the braced patients diagnosed with early onset scoliosis in a private scoliosis center. All patients diagnosed with EOS and braced before the age of ten were retrospectively reviewed. The results have been defined in accordance with the Scoliosis Research Society (SRS) for bracing criteria, and with a minimum follow-up of one year. Improvement and stabilization were considered successful treatments, while failure was considered to be an unsuccessful treatment. Successful results were observed in 80% of patients (63% worst case). In the success group, the Cobb angle was reduced from 36.3° (21–68) to 25° (10–43), with 36% of patients being initially treated only with night-time bracing. Twenty percent of the patients failed, seven had more than 45° at the last control and five had undergone surgery. This study suggests that bracing, using a modern 3D-brace concept, could be an effective treatment option for early onset scoliosis and advocates exploring its effectiveness as an alternative to casting throughout studies of higher levels of evidence.

Screening of cancer predisposition syndromes

Pediatric patients with cancer predisposition syndromes are at increased risk of developing malignancies compared with their age-matched peers, necessitating regular surveillance. Screening protocols differ among syndromes and are composed of a number of elements, imaging being one. Surveillance can be initiated in infants, children and adolescents with a tumor known or suspected of being related to a cancer predisposition syndrome or where genetic testing identifies a germline pathogenic gene variant in an asymptomatic child. Pre-symptomatic detection of malignant neoplasms offers potential to improve treatment options and survival outcomes, but the benefits and risks of screening need to be weighed, particularly with variable penetrance in many cancer predisposition syndromes. In this review we discuss the benefits and risks of surveillance imaging and the importance of integrating imaging and non-imaging screening elements. We explore the principles of surveillance imaging with particular reference to whole-body MRI, considering the strategies to minimize false-negative and manage false-positive whole-body MRI results, the value of standardized nomenclature when reporting risk stratification to better guide patient management, and the need for timely communication of results to allay anxiety. Cancer predisposition syndrome screening is a multimodality, multidisciplinary and longitudinal process, so developing formalized frameworks for surveillance imaging programs should enhance diagnostic performance while improving the patient experience.

Do We Have Viable Protective Strategies against Anesthesia-Induced Developmental Neurotoxicity?

Since its invention, general anesthesia has been an indispensable component of modern surgery. While traditionally considered safe and beneficial in many pathological settings, hundreds of preclinical studies in various animal species have raised concerns about the detrimental and long-lasting consequences that general anesthetics may cause to the developing brain. Clinical evidence of anesthetic neurotoxicity in humans continues to mount as we continue to contemplate how to move forward. Notwithstanding the alarming evidence, millions of children are being anesthetized each year, setting the stage for substantial healthcare burdens in the future. Hence, furthering our knowledge of the molecular underpinnings of anesthesia-induced developmental neurotoxicity is crucially important and should enable us to develop protective strategies so that currently available general anesthetics could be safely used during critical stages of brain development. In this mini-review, we provide a summary of select strategies with primary focus on the mechanisms of neuroprotection and potential for clinical applicability. First, we summarize a diverse group of chemicals with the emphasis on intracellular targets and signal-transduction pathways. We then discuss epigenetic and transgenerational effects of general anesthetics and potential remedies, and also anesthesia-sparing or anesthesia-delaying approaches. Finally, we present evidence of a novel class of anesthetics with a distinct mechanism of action and a promising safety profile.

Anesthesia and Developing Brains: Unanswered Questions and Proposed Paths Forward

Anesthetic agents disrupt neurodevelopment in animal models, but evidence in humans is mixed. The morphologic and behavioral changes observed across many species predicted that deficits should be seen in humans, but identifying a phenotype of injury in children has been challenging. It is increasingly clear that in children, a brief or single early anesthetic exposure is not associated with deficits in a range of neurodevelopmental outcomes including broad measures of intelligence. Deficits in other domains including behavior, however, are more consistently reported in humans and also reflect findings from nonhuman primates. The possibility that behavioral deficits are a phenotype, as well as the entire concept of anesthetic neurotoxicity in children, remains a source of intense debate. The purpose of this report is to describe consensus and disagreement among experts, summarize preclinical and clinical evidence, suggest pathways for future clinical research, and compare studies of anesthetic agents to other suspected neurotoxins.

Safety and Efficacy of Ketamine-Fentanyl-Dexmedetomidine-Induced Anesthesia and Analgesia in Neonatal and Aged Rats

The efficiency of many anesthetic regimens is controversial, with side effects especially in the vulnerable children and old population. The study aimed to evaluate the safety and efficacy of low-dose combination of ketamine, fentanyl, and dexmedetomidine (KFD) for anesthesia and analgesia in the neonatal and elderly rats. KFD rapidly induced anesthesia and analgesia in either postnatal days 6 (P6) or 13 months (13M) old rats. Meanwhile, KFD administration had no adverse effects on the cardiovascular and respiratory systems. Compared with control group, there were no distinct morphologic changes in kidney, liver, and brain in KFD group. Moreover, administration of KFD had no influence on hepatic and renal function in rats of both ages. Furthermore, there was no obvious difference in cognitive function between control and KFD groups. These results indicated that the administration of KFD combination offered safe and efficient anesthesia. Collectively, our results suggest the potential implication of the KFD combination in anesthesia management.

How much does depth matter? Magnetically controlled growing rod distraction directly influenced by rod tissue depth

PURPOSE

Magnetically controlled growing rod (MCGR) for the treatment of early-onset scoliosis (EOS) is a relatively innovative technique. MCGR benefits over traditional growing rods are known but limitations and complications are being revealed. The purpose of this study was to examine the importance of tissue depth on rod lengthening.

METHODS

A single-institution retrospective review of 72 MCGR patients was performed. Ultrasound measured rod distraction. Differences in programmed and actual distraction, and complications were recorded. Tissue depths and achieved length were averaged and used to construct a regression to account for variability.

RESULTS

Percentage of std and offset orientation rod lengthening relative to the programmed distraction was inversely proportional to rod depth (std R = 0.50, p = 0.002) (offset R = 0.60, p < 0.001). Expected std rod lengthening achieved decreased by 1.46%/mm depth. Expected offset rod lengthening achieved decreased by 1.68%/mm depth. 28 pts (38.9%) sustained complications. Age, sex, BMI, standard tissue depth, and/or offset tissue depth had no predictive ability with respect to complications sustained (overall model R = 0.31, p = 0.36).

CONCLUSION

In a series of EOS surgical patients treated with MCGRs, the relationship between percentage of programmed lengthening achieved as well as total lengthening was inversely proportional to tissue depth of the rod. There was a trend towards increasing frequency of complications recorded with decreasing tissue depth though this was not significant. These data can help with surgical planning during MCGR placement.

Glial cell-derived neurotrophic factor decrease may mediate learning, memory and behavior impairments in rats after neonatal surgery

Patients who have surgery during the first few years of their lives may have an increased risk of behavioral abnormality. Our previous study has shown a role of glial cell-derived neurotrophic factor (GDNF) in neonatal surgery-induced learning and memory impairment in rats. This study was designed to determine whether neonatal surgery induced hyperactive behavior in addition to learning and memory impairment and whether GDNF played a role in these changes. Postnatal day 7 male and female Sprague-Dawley rats were subjected to right common carotid arterial exposure under sevoflurane anesthesia. Their learning, memory and behavior were tested from 23 days after the surgery. GDNF was injected intracerebroventricularly at the end of surgery. Surgery reduced GDNF expression in the hippocampus. Surgery impaired learning and memory and induced a hyperactive behavior as assessed by Barnes maze, fear conditioning and open field tests. In addition, surgery reduced dendritic arborization and spine density. The effects were attenuated by GDNF injection. These results suggest that surgery induces a hyperactive behavior pattern, impairment of learning and memory, and neuronal microstructural damage later in the lives in rats. GDNF reduction may mediate these surgical effects.

Electroencephalogram Signatures of Agitation Induced by Sevoflurane and Its Association With Genetic Polymorphisms

Background: Volatile anesthetic-induced agitation, also called paradoxical excitation, is not uncommon during anesthesia induction. Clinically, patients with agitation may lead to self-injury or disrupt the operative position, increasing the incidence of perioperative adverse events. The study was designed to investigate clinical features of sevoflurane-induced agitation and examined whether any gene polymorphisms can potentially be used to predict agitation.

Methods: One hundred seventy-six patients underwent anesthesia induction with sevoflurane were included in this study. Frontal electroencephalogram (EEG), electromyography (EMG), and hemodynamics were recorded continuously during anesthesia induction. DNA samples were genotyped using the Illumina Infinium Asian Screening Array and the SNaPshot technology. Genetic association was analyzed by genome-wide association study. Logistic regression analysis was used to determine the role of variables in the prediction of agitation.

Results: Twenty-five (14.2%) patients experienced agitation. The depth of anesthesia index (Ai index) (p < 0.001), EMG (p < 0.001), heart rate (HR) (p < 0.001), and mean arterial pressure (MAP) (p < 0.001) rapidly increased during the agitation. EEG exhibited a shift toward high frequencies with spikes during agitation. The fast waves (alpha and beta) were more pronounced and the slow rhythms (delta) were less prominent during the occurrence of agitation. Moreover, three SNPs in the methionine synthase reductase (MTRR) gene were correlated to the susceptibility to agitation (p < 5.0 × 10⁻⁶). Carrying rs1801394 A > G (odds ratio 3.50, 95% CI 1.43–9.45) and/or rs2307116 G > A (3.31, 1.36–8.95) predicted a higher risk of agitation.

Discussion: This study suggests that the agitation/paradoxical excitation induced by sevoflurane is characterized as increases in Ai index, EMG, HR and MAP, and the high frequency with spikes in EEG. Moreover, our results provide preliminary evidence for MTRR genetic polymorphisms, involving folate metabolism function, may be related to the susceptibility to agitation.

Clinical Trial Number and Registry URL: ChiCTR1900026218; http://www.chictr.org.cn/showproj.aspx?proj=40655.

General Anesthesia During Neurodevelopment Reduces Autistic Behavior in Adult BTBR Mice, a Murine Model of Autism

Preclinical studies suggest that repeated exposure to anesthetics during a critical period of neurodevelopment induces long-term changes in synaptic transmission, plasticity, and behavior. Such changes are of great concern, as similar changes have also been identified in animal models of neurodevelopmental disorders (NDDs) such as autism. Because of overlapping synaptic changes, it is also possible that anesthetic exposures have a more significant effect in individuals diagnosed with NDDs. Thus, we evaluated the effects of early, multiple anesthetic exposures in BTBR mice, an inbred strain that displays autistic behavior. We discovered that three cycles of sevoflurane anesthesia (2.5%, 1 h) with 2-h intervals between each exposure in late postnatal BTBR mice did not aggravate, but instead improved pathophysiological mechanisms involved with autistic behavior. Sevoflurane exposures restored E/I balance (by increasing inhibitory synaptic transmission), and increased mitochondrial respiration and BDNF signaling in BTBR mice. Most importantly, such changes were associated with reduced autistic behavior in BTBR mice, as sociability was increased in the three-chamber test and repetitive behavior was reduced in the self-grooming test. Our results suggest that anesthetic exposures during neurodevelopment may affect individuals diagnosed with NDDs differently.

Prophylactic progesterone prevents adverse behavioural and neurocognitive effects of neonatal anaesthesia exposure in rat

BACKGROUND

Evidence from animal models and human studies suggests an association between early general anaesthesia exposure and development of long-lasting neurocognitive problems including learning and memory impairments and an anxious phenotype. Because millions of children each year undergo procedures that require anaesthesia, it is important to investigate ways to protect the vulnerable developing brain. We evaluated whether progesterone treatment administered before general anaesthesia exposure could prevent long-term anaesthesia-induced neurocognitive and behavioural changes.

METHODS

Female and male Long-Evans rat pups were repeatedly exposed to 2 h of sevoflurane or control procedures at postnatal days 7, 10, and 13. Subcutaneous injections of progesterone or vehicle were administered immediately before general anaesthesia exposure or control procedures. Neurobehavioural and cognitive outcomes were evaluated using elevated plus maze and Morris water maze tests.

RESULTS

Prophylactic progesterone treatment attenuated the chemokine (C-X-C motif) ligand 1 (CXCL1) response to sevoflurane exposure. Rats given vehicle treatment with general anaesthesia exposure exhibited increased anxiety on the elevated plus maze and learning and memory impairments on the Morris water maze. However, rats treated with progesterone before general anaesthesia lacked these impairments and performed in a similar manner to controls on both tasks.

CONCLUSIONS

Progesterone attenuated the anaesthesia-induced, acute peripheral inflammatory response and prevented cognitive and behavioural alterations associated with early repeated general anaesthesia exposure. Importantly, our results suggest that progesterone treatments given before general anaesthesia may help to protect the developing brain.

Longitudinal assessment of cognitive function in young children undergoing general anaesthesia

BACKGROUND

Exposure to general anaesthesia in children may be related to deficits in certain areas of cognition. It is unclear if these deficits could be measured in the immediate postoperative period in young children. The goal of the current study was to evaluate the trajectory of cognitive function in the domains of processing speed, working memory, and fine motor skills amongst children aged 2.5-6 yr who underwent general anaesthesia for elective surgery.

METHODS

Children who were scheduled to receive general anaesthesia for surgery were recruited for assessment of cognitive function at three times: preoperatively, 1-2 weeks postoperatively, and 3 months postoperatively. Assessments included processing speed, working memory, and fine motor skills. To assess longitudinal changes in the cognitive outcomes, linear mixed models were built with visit number included as a categorical variable and subject-specific random intercepts.

RESULTS

Sixty-one children (33 girls [54%]) enrolled in the study. Twenty-three children (38%) had received general anaesthesia previously. Significant improvements in picture memory, cancellation, and the processing speed composite were found at Visit 2. The improvement in cancellation and processing speed composite remained significant at Visit 3. Statistically significant improvement in Mullen fine motor score was noticed at Visit 3 compared with Visit 1. The pattern of results did not depend upon prior anaesthesia exposure.

CONCLUSIONS

General anaesthesia for elective surgery in young children was not associated with declines in working memory, processing speed, and fine motor skills in the first 3 months postoperatively, including in children with prior exposure to anaesthesia.

Epitranscriptomic Analysis of N6-methyladenosine in Infant Rhesus Macaques after Multiple Sevoflurane Anesthesia

Clinical investigations to date have proposed the possibility that exposure to anesthetics is associated with neurodevelopmental deficits. Sevoflurane is the most commonly used general anesthetic in pediatric patients. Animal studies have demonstrated that multiple exposures to sevoflurane during the postnatal period resulted in neuropathological brain changes and long-term cognitive deficits. However, the underlying mechanisms remain to be clarified. In this study, methylated RNA immunoprecipitation sequencing (MeRIP-Seq) was performed to acquire genome-wide profiling of RNA N6-methyladenosine (m⁶A) in the prefrontal cortex of infant rhesus macaques. The macaques in the sevoflurane group had more m⁶A peaks than the macaques in the control group (p ≤ 0.05). After sevoflurane treatment, the mRNA levels of YT521-B homology domain family 1 (YTHDF1) and YT521-B homology domain family 3 (YTHDF3) were decreased, and sevoflurane anesthesia dynamically regulated RNA m⁶A methylation. Gene ontology (GO) analysis revealed that after sevoflurane exposure, genes with increased methylation of m⁶A sites were enriched in some physiological processes relevant to neurodevelopment, mainly focused on synaptic plasticity. The female macaques had 18 hypermethylated genes. The males had 35 hypermethylated genes, and some physiological processes related to the regulation of synaptic structure were enriched. Rhesus macaques are genetically closer to human beings. Our findings can help in the study of the mechanism of sevoflurane-relevant neurodevelopmental deficits at the posttranscriptional level and can provide new insights into potential clinical preventions and interventions for the neurotoxicity of neonatal anesthesia exposure.

Testosterone attenuates sevoflurane-induced tau phosphorylation and cognitive impairment in neonatal male mice

BACKGROUND

Sevoflurane anaesthesia induces phosphorylation of the microtubule-associated protein tau and cognitive impairment in neonatal, but not adult, mice. The underlying mechanisms remain largely to be determined. Sex hormones can be neuroprotective, but little is known about the influence of testosterone on age-dependent anaesthesia effects.

METHODS

Six- and 60-day-old male mice received anaesthesia with sevoflurane 3% for 2 h daily for 3 days. Morris water maze, immunoassay, immunoblotting, co-immunoprecipitation, nanobeam technology, and electrophysiology were used to assess cognition; testosterone concentrations; tau phosphorylation; glycogen synthase kinase-3β (GSK3β) activation; binding or interaction between tau and GSK3β; and neuronal activation in mice, cells, and neurones.

RESULTS

Compared with 60-day-old male mice, 6-day-old male mice had lower testosterone concentrations (3.03 [0.29] vs 0.44 [0.12] ng ml^-1; P<0.01), higher sevoflurane-induced tau phosphorylation in brain (133 [20]% vs 100 [6]% in 6-day-old mice, P<0.01; 103 [8]% vs 100 [13]% in 60-day-old mice, P=0.77), and sevoflurane-induced cognitive impairment. Testosterone treatment increased brain testosterone concentrations (1.76 [0.10] vs 0.39 [0.05] ng ml^-1; P<0.01) and attenuated the sevoflurane-induced tau phosphorylation and cognitive impairment in neonatal male mice. Testosterone inhibited the interaction between tau and GSK3β, and attenuated sevoflurane-induced inhibition of excitatory postsynaptic currents in hippocampal neurones.

CONCLUSIONS

Lower brain testosterone concentrations in neonatal compared with adult male mice contributed to age-dependent tau phosphorylation and cognitive impairment after sevoflurane anaesthesia. Testosterone might attenuate the sevoflurane-induced tau phosphorylation and cognitive impairment by inhibiting the interaction between tau and GSK3β.

Blockade of the NLRP3/caspase-1 axis attenuates ketamine-induced hippocampus pyroptosis and cognitive impairment in neonatal rats

Background

Multiple studies have revealed that repeated or long-term exposure to ketamine causes neurodegeneration and cognitive dysfunction. Pyroptosis is an inflammatory form of programmed cell death that has been linked to various neurological diseases. However, the role of NLRP3/caspase-1 axis-related pyroptosis in ketamine-induced neurotoxicity and cognitive dysfunction remains uncertain.

Methods

To evaluate whether ketamine caused NLRP3/caspase1-dependent pyroptosis, flow cytometry analysis, western blotting, ELISA test, histopathological analysis, Morris water maze (MWM) test, cell viability assay, and lactate dehydrogenase release (LDH) assay were carried out on PC12 cells, HAPI cells, and 7-day-old rats. In addition, the NLRP3 inhibitor MCC950 or the caspase-1 inhibitor VX-765 was used to investigate the role of the NLRP3/caspase-1 axis in ketamine-induced neurotoxicity and cognitive dysfunction.

Results

Our findings demonstrated that ketamine exposure caused cell damage and increased the levels of pyroptosis in PC12 cells, HAPI cells, and the hippocampus of neonatal rats. After continuous exposure to ketamine, targeting NLRP3 and caspase-1 with MCC950 or VX765 improved pyroptosis, reduced neuropathological damages, and alleviated cognitive dysfunction.

Conclusion

NLRP3/Caspase-1 axis-dependent pyroptosis is involved in ketamine-induced neuroinflammation and cognitive dysfunction, and it provides a promising strategy to treat ketamine-related neurotoxicity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12974-021-02295-9.

Opioid-free anesthesia with interfascial dexmedetomidine in a high-risk infant

Despite the advances in pediatric anesthesia, infants have higher mortality and critical incidents rates than children, especially ex-prematures and those with comorbidity. We present the case of a high-risk infant who underwent elective laparoscopic gastrostomy under opioid-free anesthesia (OFA) combined with transversus abdominis plane (TAP) block with Dexmedetomidine (DEX). Perioperative opioids were entirely avoided, and intraoperative anesthetics and postoperative analgesic were considerably reduced. The infant showed cardiorespiratory stability and optimal analgesia during the uneventful procedure and the postoperative period. We consider OFA and TAP block with DEX a safe and effective anesthetic combination for high-risk infants.

Association Between Exposure of Children to General Anesthesia and Autism Spectrum Disorder

This study tested the hypothesis that exposure of children prior to their third birthday to procedures requiring general anesthesia is associated with an increased incidence of autism spectrum disorder (ASD) in later life. This study employed a nested, 1:2 matched-case control study design using ASD cases identified in a population-based birth cohort of children born in Olmsted County, MN from 1976 to 2000. Matching variables included sex, date of birth, and mother's age in conditional logistic regression including 499 ASD cases and 998 controls. After adjusting for birth weight and health status, there was no significant association between exposure and ASD (OR 1.27 [95% CI 0.92-1.76]), indicating that general anesthesia is not associated with an increased risk of ASD.

The potential role of stress and sex steroids in heritable effects of sevoflurane†

Most surgical procedures require general anesthesia, which is a reversible deep sedation state lacking all perception. The induction of this state is possible because of complex molecular and neuronal network actions of general anesthetics (GAs) and other pharmacological agents. Laboratory and clinical studies indicate that the effects of GAs may not be completely reversible upon anesthesia withdrawal. The long-term neurocognitive effects of GAs, especially when administered at the extremes of ages, are an increasingly recognized health concern and the subject of extensive laboratory and clinical research. Initial studies in rodents suggest that the adverse effects of GAs, whose actions involve enhancement of GABA type A receptor activity (GABAergic GAs), can also extend to future unexposed offspring. Importantly, experimental findings show that GABAergic GAs may induce heritable effects when administered from the early postnatal period to at least young adulthood, covering nearly all age groups that may have children after exposure to anesthesia. More studies are needed to understand when and how the clinical use of GAs in a large and growing population of patients can result in lower resilience to diseases in the even larger population of their unexposed offspring. This minireview is focused on the authors' published results and data in the literature supporting the notion that GABAergic GAs, in particular sevoflurane, may upregulate systemic levels of stress and sex steroids and alter expressions of genes that are essential for the functioning of these steroid systems. The authors hypothesize that stress and sex steroids are involved in the mediation of sex-specific heritable effects of sevoflurane.

Moderators of the association between attention-deficit/hyperactivity disorder and exposure to anaesthesia and surgery in children

BACKGROUND

Children's exposure to anaesthesia has been associated with risk of developing attention-deficit/hyperactivity disorder (ADHD). The goal of this study was to determine if selected patient characteristics moderate the association between exposure to anaesthesia and ADHD.

METHODS

In a cohort of children born in between 2006 and 2012, exposure to anaesthesia before the age of 5 yr was categorised into unexposed, singly, or multiply exposed. Weighted proportional hazard regression was performed to evaluate the hazard ratios (HRs) of ADHD diagnosis related to anaesthesia exposure. Interaction analyses were performed to evaluate potential moderators.

RESULTS

Among 185 002 children in the cohort, 9179 were diagnosed with ADHD. Compared with unexposed children, a single exposure to anaesthesia was associated with a HR of 1.39, (95% confidence interval [CI], 1.32-1.47) for ADHD. Multiple exposures were associated with a HR of 1.75 (95% CI, 1.62-1.87). In the analyses evaluating moderators of the association between exposure and ADHD, only the interaction for race was statistically significant (P=0.006); exposure increased the incidence of ADHD to a greater extent in non-White compared with White children. Among children with a single exposure, the age at exposure did not affect the relationship between exposure and incidence of ADHD (P=0.78).

CONCLUSIONS

Exposure of young children to anaesthesia and surgery is associated with an increased incidence of ADHD, with more exposures associated with greater risk. Compared with White children, non-White children are at greater risk for reasons that are unknown but need to be further explored.

Histone Deacetylase 2-Mediated Epigenetic Regulation is Involved in the Early Isoflurane Exposure-Related Increase in Susceptibility to Anxiety-Like Behaviour Evoked by Chronic Variable Stress in Mice

Increasing studies report that prolonged or multiple anaesthetic exposures early in life are associated with detrimental effects on brain function. Although studies have evaluated the detrimental effects on neurocognitive function, few have focused on long-term neuropsychiatric effects. In the present study, C57BL/6 mice received either three neonatal isoflurane exposures or control exposure. Starting on postnatal day 45, the mice were either exposed or not to a chronic variable stress (CVS) paradigm, and CVS-related neuropsychiatric performance was evaluated using a series of behavioural tests. The expression levels of histone 3 lysine 9 acetylation (acetyl-H3K9), brain-derived neurotrophic factor (BDNF), cAMP response element-binding protein-binding protein, and histone deacetylases 1-4 in the amygdala were measured by immunoblotting or immunohistochemistry analysis. In mice with neonatal isoflurane exposure, the effects of sodium butyrate (NaB), a commonly used HDAC inhibitor, were examined on CVS-related behavioural and molecular alterations. The results showed that repeated neonatal isoflurane exposure did not affect innate depression-like and anxiety-like behaviours under non-stress conditions but facilitated the CVS-induced anxiety-like behavioural phenotype. Increased HDAC2 expression in the amygdala was associated with an increase in the CVS-induced repression of acetyl-H3K9 and BDNF expression and an enhanced CVS-evoked anxiety-like behavioural phenotype in mice neonatal isoflurane exposure. NaB significantly decreased the CVS-induced anxiety level by elevating acetyl-H3K9 and BDNF expression. These results suggested that early anaesthesia exposure facilitated chronic stress-induced neuropsychiatric outcomes, and the HDAC2-related epigenetic dysregulation of BDNF gene expression is involved in the underlying mechanism.

Exposure to general anaesthesia in childhood and the subsequent risk of attention-deficit hyperactivity disorder: A meta-analysis of cohort studies

BACKGROUND

The evidence for a relationship between general anaesthesia induced in childhood and the risk of attention-deficit hyperactivity disorder (ADHD) in later life is inconsistent. We systematically assessed whether such an association existed.

METHODS

We searched the PubMed and EMBASE databases for relevant cohort studies. Relative risks (RRs) and 95 % confidence intervals (CIs) were calculated to determine the relationship between induction of childhood general anaesthesia and the risk of ADHD in later life.

RESULTS

Seven studies (eight publications) on developmental outcomes after the induction of childhood general anaesthesia met our inclusion criteria but not our exclusion criteria. Repeat childhood general anaesthesia (RR = 1.84, 95 CI% 1.14-2.97; P < 0.001; I² = 74.8 %), but not one-off general anaesthesia (RR = 1.09, 95 CI% 0.93-1.27; P = 0.301; I² = 0%), was associated with an increased risk of ADHD in later life. The association was evident only when the total general anaesthesia exposure exceeded 90 min.

CONCLUSIONS

Our meta-analysis indicated that the effect of general anaesthesia on the risk of ADHD is dose- or duration-dependent.

Intranasal insulin rescues repeated anesthesia-induced deficits in synaptic plasticity and memory and prevents apoptosis in neonatal mice via mTORC1

Long-lasting cognitive impairment in juveniles undergoing repeated general anesthesia has been observed in numerous preclinical and clinical studies, yet, the underlying mechanisms remain unknown and no preventive treatment is available. We found that daily intranasal insulin administration to juvenile mice for 7 days prior to repeated isoflurane anesthesia rescues deficits in hippocampus-dependent memory and synaptic plasticity in adulthood. Moreover, intranasal insulin prevented anesthesia-induced apoptosis of hippocampal cells, which is thought to underlie cognitive impairment. Inhibition of the mechanistic target of rapamycin complex 1 (mTORC1), a major intracellular effector of insulin receptor, blocked the beneficial effects of intranasal insulin on anesthesia-induced apoptosis. Consistent with this finding, mice lacking mTORC1 downstream translational repressor 4E-BP2 showed no induction of repeated anesthesia-induced apoptosis. Our study demonstrates that intranasal insulin prevents general anesthesia-induced apoptosis of hippocampal cells, and deficits in synaptic plasticity and memory, and suggests that the rescue effect is mediated via mTORC1/4E-BP2 signaling.

Astrogliosis in juvenile non-human primates 2 years after infant anaesthesia exposure

BACKGROUND

Infant anaesthesia causes acute brain cell apoptosis, and later in life cognitive deficits and behavioural alterations, in non-human primates (NHPs). Various brain injuries and neurodegenerative conditions are characterised by chronic astrocyte activation (astrogliosis). Glial fibrillary acidic protein (GFAP), an astrocyte-specific protein, increases during astrogliosis and remains elevated after an injury. Whether infant anaesthesia is associated with a sustained increase in GFAP is unknown. We hypothesised that GFAP is increased in specific brain areas of NHPs 2 yr after infant anaesthesia, consistent with prior injury.

METHODS

Eight 6-day-old NHPs per group were exposed to 5 h isoflurane once (1×) or three times (3×), or to room air as a control (Ctr). Two years after exposure, their brains were assessed for GFAP density changes in the primary visual cortex (V1), perirhinal cortex (PRC), hippocampal subiculum, amygdala, and orbitofrontal cortex (OFC). We also assessed concomitant microglia activation and hippocampal neurogenesis.

RESULTS

Compared with controls, GFAP densities in V1 were increased in exposed groups (Ctr: 0.208 [0.085-0.427], 1×: 0.313 [0.108-0.533], 3×: 0.389 [0.262-0.652]), whereas the density of activated microglia was unchanged. In addition, GFAP densities were increased in the 3× group in the PRC and the subiculum, and in both exposure groups in the amygdala, but there was no increase in the OFC. There were no differences in hippocampal neurogenesis among groups.

CONCLUSIONS

Two years after infant anaesthesia, NHPs show increased GFAP without concomitant microglia activation in specific brain areas. These long-lasting structural changes in the brain caused by infant anaesthesia exposure may be associated with functional alterations at this age.

Association Between Behavioral and Learning Outcomes and Single Exposures to Procedures Requiring General Anesthesia Before Age 3: Secondary Analysis of Data From Olmsted County, MN

BACKGROUND

Two prior population-based (children born in Olmsted County, MN), retrospective cohort studies both found that multiple exposures to anesthesia before age 3 were associated with a significant increase in the frequency of attention-deficit hyperactivity disorder (ADHD) and learning disabilities (LD) later in life. The primary purpose of this secondary analysis of these data was to test the hypothesis that a single exposure to anesthesia before age 3 was associated with an increased risk of ADHD. We also examined the association of single exposures with LD and the need for individualized educational plans as secondary outcomes.

METHODS

This analysis includes 5339 children who were unexposed to general anesthesia before age 3 (4876 born from 1976 to 1982 and 463 born from 1996 to 2000), and 1054 children who had a single exposure to anesthesia before age 3 (481 born from 1976 to 1982 and 573 born from 1996 to 2000). The primary outcome of interest was ADHD. Secondary outcomes included LD (reading, mathematics, and written language) and the need for individualized educational programs (speech/language and emotion/behavior). To compare the incidence of each outcome between those who were unexposed and singly exposed to anesthesia before the age of 3 years, an inverse probability of treatment weighted proportional hazards model was used.

RESULTS

For children not exposed to anesthesia, the estimated cumulative frequency (95% confidence interval [CI]) of ADHD at age 18 was 7.3% (95% CI, 6.5-8.1) and 13.0% (95% CI, 10.1-16.8) for the 1976-1982 and 1996-2000 cohorts, respectively. For children exposed to a single anesthetic before age 3, the cumulative frequency of ADHD was 8.1% (95% CI, 5.3-12.4) and 17.6% (95% CI, 14.0-21.9) for the 1976-1982 and 1996-2000 cohorts, respectively. In weighted analyses, single exposures were not significantly associated with an increased frequency of ADHD (hazard ratio [HR], 1.21; 95% CI, 0.91-1.60; P = .184). Single exposures were also not associated with an increased frequency of any LD (HR, 0.98; 95% CI, 0.78-1.23), or the need for individualized education plans.

CONCLUSIONS

This analysis did not find evidence that single exposures to procedures requiring general anesthesia, before age 3, are associated with an increased risk of developing ADHD, LD, or the need for individualized educational plans in later life.

Comparing Results of Syndactyly Operated Children Younger and Older Than 1 Year

INTRODUCTION

Syndactyly has a cosmetic, functional, and psychosocial impact, and surgical treatment is indicated in most cases. This study aimed to retrospectively identify whether patients undergoing surgical release of syndactyly younger than 1 year presented different results compared with those operated older than 1 year.

METHODS

Patients were assessed through photographic records by 3 independent specialist surgeons for the quality of scar, presence of web creep, rotational, flexion-extension, and lateral flexion deformities using the Withey score.

RESULTS

Thirty-four patients were included in the study, totaling 51 commissures operated. The score was higher in the group operated younger than 1 year (5.83 ± 2.39) compared with the group older than 1 year (3.94 ± 1.93), being statistically significant, with a P value of 0.011.

CONCLUSIONS

Children with syndactyly operated younger than 1 year have worse postoperative outcomes measured by the Withey score than those operated older than 1 year.

Why do We Use the Concepts of Adult Anesthesia Pharmacology in Developing Brains? Will It Have an Impact on Outcomes? Challenges in Neuromonitoring and Pharmacology in Pediatric Anesthesia

BACKGROUND

Pediatric sedation and anesthesia techniques have plenty of difficulties and challenges. Data on the pharmacologic, electroencephalographic, and neurologic response to anesthesia at different brain development times are only partially known. New data in neuroscience, pharmacology, and intraoperative neuromonitoring will impact changing concepts and clinical practice. In this article, we develop a conversation to guide the debate and search for a view more attuned to the updated knowledge in neurodevelopment, electroencephalography, and clinical pharmacology for the anesthesiologic practice in the pediatric population.