Anesthesia and Developing Brains: Unanswered Questions and Proposed Paths Forward

Association between general anesthesia in early childhood and neurodevelopment up to 4 years of age: the Japan Environment and Children's Study

PURPOSE

The effects of general anesthesia on neurodevelopment in children remain controversial. We explored the relationship between general anesthesia and neurodevelopment in children participating in the Japan Environment and Children's Study (JECS).

METHODS

This study enrolled children born between 37 and 41 weeks of pregnancy via single-vaginal delivery to pregnant women registered in the JECS between January 2011 and March 2014. Data were collected from mother-completed questionnaires and medical transcripts. Neurodevelopment in five domains was assessed every 6 months between 12 and 48 months of age, using the Ages and Stages Questionnaires. The associations between general anesthesia exposure during early childhood and neurodevelopment in children were evaluated at each time point. Adjusted odds ratios and 95% confidence intervals were estimated after covariate adjustment using logistic regression models.

RESULTS

Children who received general anesthesia before age 1 year had higher risks of neurodevelopmental delay in all five domains throughout the observational period. The largest risk was for gross motor delay at 18 months (adjusted odds ratio: 3.51; 95% confidence interval: 2.75-4.49). The effects on the incidence of neurodevelopmental delays after age 3 were not observed except for problem solving at 48 months. The risk of neurodevelopmental delay in children who first received general anesthesia after age 1 was considerably small.

CONCLUSIONS

This study suggests that general anesthesia administration before age 1 is associated with neurodevelopmental delay during 1-4 years of age. The risk of general anesthesia after age 1 may be small.

Gut Microbiota-Metabolite-Brain Axis Reconstitution Reverses Sevoflurane-Induced Social and Synaptic Deficits in Neonatal Mice

Background: The mechanisms underlying social dysfunction caused by repeated sevoflurane in early life remain unclear. Whether the gut microbiota-metabolite-brain axis is involved in the mechanism of sevoflurane developmental neurotoxicity still lacks report. Methods: Mice received 3% sevoflurane at postnatal day (PND) 6, 7, and 8 for 2 h per day. Metagenomic sequencing and untargeted metabolomic analysis were applied to investigate the effects of sevoflurane on gut microbiota and metabolism. The animal social behavior and the synaptic development were analyzed during PND 35. Subsequently, fecal microbiota transplantation (FMT) from the control group and bile acid administration were performed to see the expected rescuing effect on socially related behaviors that were impaired by repeated sevoflurane exposure in the mice. Results: In the 3-chamber test, sevoflurane-exposed mice spent less time with stranger mice compared with the control group. The density of both the apical and basal spine decreased in mice exposed to sevoflurane. In addition, repeated sevoflurane exposure led to a notable alteration in the gut microbiota and metabolite synthesis, particularly bile acid. FMT reduced the production of intestinal bile acid and attenuated the effect of sevoflurane exposure on social function and synaptic development. Cholestyramine treatment mimics the protective effects of FMT. Conclusions: The gut microbiota-metabolite-brain axis underlies social dysfunction caused by sevoflurane exposure in early age, and bile acid regulation may be a promising intervention to this impairment.

Unraveling the effects of prenatal anesthesia on neurodevelopment: A review of current evidence and future directions

Human brain development is a complex, multi-stage, and sensitive process, especially during the fetal stage. Animal studies over the last two decades have highlighted the potential risks of anesthetics to the developing brain, impacting its structure and function. This has raised concerns regarding the safety of anesthesia during pregnancy and its influence on fetal brain development, garnering significant attention from the anesthesiology community. Although preclinical studies predominantly indicate the neurotoxic effects of prenatal anesthesia, these findings cannot be directly extrapolated to humans due to interspecies variations. Clinical research, constrained by ethical and technical hurdles in accessing human prenatal brain tissues, often yields conflicting results compared to preclinical data. The emergence of brain organoids as a cutting-edge research tool shows promise in modeling human brain development. When integrated with single-cell sequencing, these organoids offer insights into potential neurotoxic mechanisms triggered by prenatal anesthesia. Despite several retrospective and cohort studies exploring the clinical impact of anesthesia on brain development, many findings remain inconclusive. As such, this review synthesizes preclinical and clinical evidence on the effects of prenatal anesthesia on fetal brain development and suggests areas for future research advancement.

Exposure to Operative Anesthesia in Childhood and Subsequent Neurobehavioral Diagnoses: A Natural Experiment Using Appendectomy

BACKGROUND

Observational studies of anesthetic neurotoxicity may be biased because children requiring anesthesia commonly have medical conditions associated with neurobehavioral problems. This study takes advantage of a natural experiment associated with appendicitis to determine whether anesthesia and surgery in childhood were specifically associated with subsequent neurobehavioral outcomes.

METHODS

This study identified 134,388 healthy children with appendectomy and examined the incidence of subsequent externalizing or behavioral disorders (conduct, impulse control, oppositional defiant, attention-deficit hyperactivity disorder) or internalizing or mood or anxiety disorders (depression, anxiety, or bipolar disorder) when compared to 671,940 matched healthy controls as identified in Medicaid data between 2001 and 2018. For comparison, this study also examined 154,887 otherwise healthy children admitted to the hospital for pneumonia, cellulitis, and gastroenteritis, of which only 8% received anesthesia, and compared them to 774,435 matched healthy controls. In addition, this study examined the difference-in-differences between matched appendectomy patients and their controls and matched medical admission patients and their controls.

RESULTS

Compared to controls, children with appendectomy were more likely to have subsequent behavioral disorders (hazard ratio, 1.04; 95% CI, 1.01 to 1.06; P = 0.0010) and mood or anxiety disorders (hazard ratio, 1.15; 95% CI, 1.13 to 1.17; P < 0.0001). Relative to controls, children with medical admissions were also more likely to have subsequent behavioral (hazard ratio, 1.20; 95% CI, 1.18 to 1.22; P < 0.0001) and mood or anxiety (hazard ratio, 1.25; 95% CI, 1.23 to 1.27; P < 0.0001) disorders. Comparing the difference between matched appendectomy patients and their matched controls to the difference between matched medical patients and their matched controls, medical patients had more subsequent neurobehavioral problems than appendectomy patients.

CONCLUSIONS

Although there is an association between neurobehavioral diagnoses and appendectomy, this association is not specific to anesthesia exposure and is stronger in medical admissions. Medical admissions, generally without anesthesia exposure, displayed significantly higher rates of these disorders than appendectomy-exposed patients.

EDITOR’S PERSPECTIVE

Maternal-Fetal Conflicts in Anesthesia Practice

Anesthesia clinicians often navigate a delicate balance between maternal and fetal safety. Interventions for at fetal well-being may introduce risks of harm to the mother and raise ethical dilemmas. Emergency procedures often focus on direct fetal safety, sidelining maternal physical and mental well-being. The clash between ethical principles, particularly nonmaleficence and beneficence, often arises, with maternal autonomy guiding decisions. Fetal surgery exemplifies risking maternal health for fetal benefit, whereas emergent cesarean deliveries pose physical and psychological challenges for both the mother and child.

Unveiling the hidden dangers: a review of non-apoptotic programmed cell death in anesthetic-induced developmental neurotoxicity

Anesthetic-induced developmental neurotoxicity (AIDN) can arise due to various factors, among which aberrant nerve cell death is a prominent risk factor. Animal studies have reported that repeated or prolonged anesthetic exposure can cause significant neuroapoptosis in the developing brain. Lately, non-apoptotic programmed cell deaths (PCDs), characterized by inflammation and oxidative stress, have gained increasing attention. Substantial evidence suggests that non-apoptotic PCDs are essential for neuronal cell death in AIDN compared to apoptosis. This article examines relevant publications in the PubMed database until April 2024. Only original articles in English that investigated the potential manifestations of non-apoptotic PCD in AIDN were analysed. Specifically, it investigates necroptosis, pyroptosis, ferroptosis, and parthanatos, elucidating the signaling mechanisms associated with each form. Furthermore, this study explores the potential relevance of these non-apoptotic PCDs pathways to the pathological mechanisms underlying AIDN, drawing upon their distinctive characteristics. Despite the considerable challenges involved in translating fundamental scientific knowledge into clinical therapeutic interventions, this comprehensive review offers a theoretical foundation for developing innovative preventive and treatment strategies targeting non-apoptotic PCDs in the context of AIDN.

Oral Health Care for Children and Youth With Developmental Disabilities: Clinical Report

Oral health is an essential component of overall health for all individuals. The oral health of children and youth with developmental disabilities (CYDD) involves unique characteristics and needs of which pediatricians and pediatric clinicians can be aware. Risk for oral disease in CYDD is multifactorial and includes underlying medical conditions, medications, and ability to participate in preventive oral health care and treatment, and lack of access to providers is common for this population despite being eligible for Medicaid. Pediatric clinicians are uniquely positioned to support the oral health needs of CYDD and their families through the medical home. This clinical report aims to inform pediatric clinicians about the unique oral health needs of CYDD. It provides guidance on assessing caries risk and periodontal status using structured screening instruments; understanding dental trauma, the role of diet and caries risk, trauma prevention, and malocclusion; and providing anticipatory guidance on oral hygiene that includes tooth brushing, use of fluoridated toothpaste, assessing community water fluoridation, advocating for a dental home by 1 year of age, and transition to adult dental care as part of adolescent health care. It also highlights special considerations for dental treatment rendered under sedation or general anesthesia that CYDD may need. Pediatric clinicians can help reduce risk of CYDD developing dental disease by understanding the unique needs of their patients and their barriers to accessing oral health care in their community, communicating with the child's dental home, and advocating for safe and accessible dental procedures.

Exposure to lidocaine in early life does not cause negative long-term behavioural changes in mice

BACKGROUND

The local anaesthetic lidocaine is widely used in the neonatal intensive unit to treat seizures in premature babies. However, other antiepileptics administered during early development in various animal models have shown negative long-term behavioural effects. Since no long-term behavioural data so far exist regarding lidocaine exposure at an early age, we decided to perform this extended follow-up study using a sensitive behavioural test.

METHODS

Neonatal mice received a subcutaneous administration of saline or one dose of lidocaine (0.5, 4, or 12 mg kg-1) on postnatal day 10 (P10; peak of the Brain Growth Spurt). A well-established test to detect long-term behavioural alterations was conducted at 2 and 6 months of age, corresponding to early and late adulthood in humans.

RESULTS

All animal survived to later testing. No signs of acute toxicity were observed. Lidocaine exposure did not result in any negative behavioural effects during habituation to a new home environment at any of the two studied time points, compared to saline placebo.

CONCLUSIONS

Lidocaine does not by itself produce any negative long-term behavioural effects in mice exposed in early life (P10) despite long-term follow-up. This is reassuring regarding the current practice of treating seizures in premature babies with intravenous lidocaine.

Risk of Pediatric Bipolar Disorder After General Anesthesia in Infants and Toddlers: A Propensity Score-Matched Population-Based Cohort Study

BACKGROUND AND HYPOTHESIS

The potential role of anesthesia as an independent risk factor for childhood bipolar disorder (BD) remains unclear. To address this, we conducted a population-based cohort study employing propensity score matching to compare BD incidence between pediatric patients undergoing surgery with and without general anesthesia.

STUDY DESIGN

Our study included patients aged 0-3 years who received at least 1 episode of general anesthesia and were hospitalized for over 1 day in Taiwan between January 2004 and December 2014. They were matched 1:1 with a population not receiving general anesthesia to assess pediatric BD incidence.

STUDY RESULTS

The study cohort comprised 15 070 patients, equally distributed between the general anesthesia and nongeneral anesthesia groups (7535 each). Multivariate Cox regression analysis revealed adjusted hazard ratios (aHRs; 95% CIs) for pediatric BD in the general anesthesia group as 1.26 (1.04-1.54; P = .021) compared to the nongeneral anesthesia group. Moreover, the incidence rate ratio (95% CI) for the general anesthesia group was 1.26 (1.03-1.53) compared to the nongeneral anesthesia group.

CONCLUSIONS

Early childhood exposure to general anesthesia is significantly associated with an increased risk of pediatric BD. This expands understanding of pediatric BD's complex development, informing preventive strategies, and enhancing mental health outcomes for vulnerable young patients and global pediatric healthcare.

Experiencing anesthesia and surgery early in life impairs cognitive and behavioral development

Background

The impact of anesthesia and surgery on neurocognitive and behavioral development in infants and children remains inadequately understood.

Objective

To investigate the impact of early-life exposure to general anesthesia and surgery on cognitive and behavioral development.

Methods and materials

Children aged 0-3 years who underwent general anesthesia and surgical procedures between 2012 and 2015 were included. The cognitive and behavioral development of these children at ages 4-6 years was assessed. Age-, race-, and gender-matched children from the same geographic region, who did not undergo general anesthesia or surgery, served as the control group. The Wechsler Preschool Primary Scale of Intelligence, Fourth Edition (WPPSI-IV) was used to evaluate children's total intelligence quotient (FSIQ) and specific cognitive domains. The Gesell Development Schedules (GSCH) and Child Behavior Checklist (CBCL) were employed to assess behavioral and personality development. Additionally, the study analyzed the effects of various factors including anesthesia drugs, surgery duration, number of surgeries, age, weight, ethnicity, and gender on postoperative neurocognitive and behavioral outcomes.

Results

The study included 447 children with anesthesia/surgical exposure (AS) and 459 children in the control group. Analysis of cognitive and behavioral development showed a significant difference in the working memory index (WMI) between the AS and control groups (p < 0.05). Exploratory findings indicated that children administered remifentanil exhibited lower developmental quotient (DQ) values, whereas those given fentanyl showed higher (worse) Child Behavior Checklist (CBCL) total scores. Moreover, increased anesthesia/surgical exposures, younger age and lower body weight at exposure, and longer surgery durations were associated with cognitive and behavioral developmental challenges.

Conclusion

This study examined the impact of early-life exposure to surgery and anesthesia on postoperative cognitive and behavioral development. Findings indicate that higher frequency of exposure to surgery and anesthesia, younger age, and lower body weight at exposure could negatively influence cognitive and behavioral development. Furthermore, variations in the effects of different anesthetics on behavior and cognition were observed. Caution is advised regarding the use of opioid analgesics such as remifentanil and fentanyl for more rigorous clinical applications.

Microglial EPOR Contribute to Sevoflurane-induced Developmental Fine Motor Deficits Through Synaptic Pruning in Mice

Clinical researches including the Mayo Anesthesia Safety in Kids (MASK) study have found that children undergoing multiple anesthesia may have a higher risk of fine motor control difficulties. However, the underlying mechanisms remain elusive. Here, we report that erythropoietin receptor (EPOR), a microglial receptor associated with phagocytic activity, was significantly downregulated in the medial prefrontal cortex of young mice after multiple sevoflurane anesthesia exposure. Importantly, we found that the inhibited erythropoietin (EPO)/EPOR signaling axis led to microglial polarization, excessive excitatory synaptic pruning, and abnormal fine motor control skills in mice with multiple anesthesia exposure, and those above-mentioned situations were fully reversed by supplementing EPO-derived peptide ARA290 by intraperitoneal injection. Together, the microglial EPOR was identified as a key mediator regulating early synaptic development in this study, which impacted sevoflurane-induced fine motor dysfunction. Moreover, ARA290 might serve as a new treatment against neurotoxicity induced by general anesthesia in clinical practice by targeting the EPO/EPOR signaling pathway.

Pre-school children single inhalation anesthetic exposure and neuro-psychological development: a prospective study and Mendelian randomization analysis

Background

For children who are unable to cooperate due to severe dental anxiety (DA), dental treatment of childhood caries under Dental General Anesthesia (DGA) is a safe and high-quality treatment method. This study aims to evaluate the impact on neurocognitive functions and the growth and development of children 2 years after dental procedure based on previous research, and further establish a causal relationship between general anesthesia (GA) and changes in children's neurocognitive functions by incorporating Mendelian Randomization (MR) analysis.

Methods

Data were collected and analyzed from 340 cases of S-ECC procedures of preschool children conducted in 2019. This involved comparing the neurocognitive outcomes 2 years post-operation of preschool children receiving dental procedures under general anesthesia or local anesthesia. Physical development indicators such as height, weight, and body mass index (BMI) of children were also compared at baseline, half a year post-operation, and 2 years post-operation. We performed a Mendelian randomization analysis on the causal relationship between children's cognitive development and general anesthesia, drawing on a large-scale meta-analysis of GWAS for anesthesia, including multiple general anesthesia datasets.

Results

Outcome data were obtained for 111 children in the general anesthesia group and 121 children in the local anesthesia group. The mean FSIQ score for the general anesthesia group was 106.77 (SD 6.96), while the mean score for the local anesthesia group was 106.36 (SD 5.88). FSIQ scores were equivalent between the two groups. The incidence of malnutrition in children in the general anesthesia group was 27.93% (p < 0.001) before surgery and decreased to 15.32% (p > 0.05) after 2 years, which was not different from the general population. The IVW method suggested that the causal estimate (p = 0.99 > 0.05, OR = 1.04, 95% CI = 5.98 × 10-4-1.82 × 103) was not statistically significant for disease prevalence. This indicates no genetic cause-and-effect relationship between anesthesia and childhood intelligence.

Conclusion

There were no adverse outcomes in neurocognitive development in 2 years after severe early childhood caries (S-ECC) procedure under total sevoflurane-inhalation in preschool children. The malnutrition condition in children can be improved after S-ECC procedure under general anesthesia. Limited MR evidence does not support a correlation between genetic susceptibility to anesthesia and an increased risk for intelligence in children.

Children and the Opioid Crisis: We Can Make a Difference

The use of opioid-sparing and opioid-free strategies in children can provide adequate analgesia while decreasing the risk of adverse events and contributing to the ongoing battle against the opioid crisis. However, every child must be evaluated individually so that a safe and efficacious perioperative pain management plan can be created. A working knowledge of the risks and benefits of opioids, nonopioid adjuncts, and regional anesthesia along with the ethical considerations for balancing stewardship and beneficent care is essential to the success of these strategies. As perioperative practitioners caring for children, we have an obligation to consider opioid-sparing and opioid-free strategies to promote overall best outcomes. We can make a difference, one child at a time.

NUFIP1-engineered exosomes derived from hUMSCs regulate apoptosis and neurological injury induced by propofol in newborn rats

BACKGROUND

Propofol can increase neurotoxicity in infants but the precise mechanism is still unknown. Our previous study revealed that nuclear FMR1 interacting protein 1 (NUFIP1), a specific ribophagy receptor, can alleviate T cell apoptosis in sepsis. Yet, the effect of NUFIP1-engineered exosomes elicited from human umbilical cord blood mesenchymal stem cells (hUMSCs) on nerve injury induced by propofol remains unclear. This study intended to investigate the effect of NUFIP1-engineered exosomes on propofol-induced nerve damage in neonatal rats.

METHODS

Firstly, NUFIP1-engineered exosomes were extracted from hUMSCs serum and their identification was conducted using transmission electron microscopy (TEM), Flow NanoAnalyzer, quantitative real-time polymerase chain reaction (qRT-PCR), and western blot (WB). Subsequently, the optimal exposure duration and concentration of propofol induced apoptosis were determined in SH-SY5Y cell line using WB. Following this, we co-cultured the NUFIP1-engineered exosomes in the knockdown group (NUFIP1-KD) and overexpression group (NUFIP1-OE) with SH-SY5Y cells and assessed their effects on the apoptosis of SH-SY5Y cells using terminal-deoxynucleotidyl transferase mediated nick end labeling (TUNEL) assay, Hoechst 33258 staining, WB, and flow cytometry, respectively. Finally, NUFIP1-engineered exosomes were intraperitoneally injected into neonatal rats, and their effects on the learning and memory ability of neonatal rats were observed through the righting reflex and Morris water maze (MWM) test. Hippocampi were extracted from different groups for hematoxylin-eosin (HE) staining, immunohistochemistry, immunofluorescence, and WB to observe their effects on apoptosis in neonatal rats.

RESULTS

TEM, Flow NanoAnalyzer, qRT-PCR, and WB analyses confirmed that the exosomes extracted from hUMSCs serum exhibited the expected morphology, diameter, surface markers, and expression of target genes. This confirmed the successful construction of NUFIP1-KD and NUFIP1-OE-engineered exosomes. Optimal exposure duration and concentration of propofol were determined to be 24 hours and 100 µg/ml, respectively. Co-culture of NUFIP1 engineered exosomes and SH-SY5Y cells resulted in significant up-regulation of pro-apoptotic proteins Bax and c-Caspase-3 in the KD group, while anti-apoptotic protein Bcl-2 was significantly decreased. The OE group showed the opposite trend. TUNEL apoptosis assay, Hoechst 33258 staining, and flow cytometry yielded consistent results. Animal experiments demonstrated that intraperitoneal injection of NUFIP1-KD engineered exosomes prolonged the righting reflex recovery time of newborn rats, and MWM tests revealed a significant diminution in the time and number of newborn rats entering the platform. HE staining, immunohistochemistry, immunofluorescence, and WB results also indicated a significant enhancement in apoptosis in this group. Conversely, the experimental results of neonatal rats in the OE group revealed a certain degree of anti-apoptotic effect.

CONCLUSIONS

NUFIP1-engineered exosomes from hUMSCs have the potential to regulate nerve cell apoptosis and mitigate neurological injury induced by propofol in neonatal rats. Targeting NUFIP1 may hold great significance in ameliorating propofol-induced nerve injury.

Developmental anaesthesia neurotoxicity in humans: finding the sweet spot?

A recent human epidemiological study in this issue of British Journal of Anaesthesia examined the association between anaesthesia exposure in pregnant women undergoing appendicectomy or cholecystectomy and the subsequent diagnosis of behavioural disorders in their offspring. When compared with unexposed children, prenatally exposed children had ∼30% greater likelihood of a diagnosis of disruptive or internalising behavioural disorders. Although these data are new and interesting, they should be interpreted with caution. Indeed, appendicitis and cholecystitis can produce acute and chronic systemic inflammation, and maternal immune activation can affect fetal neurodevelopment through inflammatory and epigenetic mechanisms. It is, therefore, possible that the findings are related to maternal and fetal inflammation than to anaesthesia exposure. As there is no causal evidence for the implication that anaesthesia and surgery induce such pathologies, it is unwise to consider alternative treatments when surgery is indicated in pregnant patients.

Behavioural disorders after prenatal exposure to anaesthesia for maternal surgery

BACKGROUND

The association between prenatal exposure to general anaesthesia for maternal surgery during pregnancy and subsequent risk of disruptive or internalising behavioural disorder diagnosis in the child has not been well-defined.

METHODS

A nationwide sample of pregnant women linked to their liveborn infants was evaluated using the Medicaid Analytic eXtract (MAX, 1999-2013). Multivariate matching was used to match each child prenatally exposed to general anaesthesia owing to maternal appendectomy or cholecystectomy during pregnancy with five unexposed children. The primary outcome was diagnosis of a disruptive or internalising behavioural disorder in children. Secondary outcomes included diagnoses for a range of other neuropsychiatric disorders.

RESULTS

We matched 34,271 prenatally exposed children with 171,355 unexposed children in the database. Prenatally exposed children were more likely than unexposed children to receive a diagnosis of a disruptive or internalising behavioural disorder (hazard ratio [HR], 1.31; 95% confidence interval [CI], 1.23-1.40). For secondary outcomes, increased hazards of disruptive (HR, 1.32; 95% CI, 1.24-1.41) and internalising (HR, 1.36; 95% CI, 1.20-1.53) behavioural disorders were identified, and also increased hazards of attention-deficit/hyperactivity disorder (HR, 1.32; 95% CI, 1.22-1.43), behavioural disorders (HR, 1.28; 95% CI, 1.14-1.42), developmental speech or language disorders (HR, 1.16; 95% CI, 1.05-1.28), and autism (HR, 1.31; 95% CI, 1.05-1.64).

CONCLUSIONS

Prenatal exposure to general anaesthesia is associated with a 31% increased risk for a subsequent diagnosis of a disruptive or internalising behavioural disorder in children. Caution is advised when making any clinical decisions regarding care of pregnant women, as avoidance of necessary surgery during pregnancy can have detrimental effects on mothers and their children.

Modern Radiation Treatment Planning Parameters and Outcomes in Pediatric Tectal Gliomas

Purpose

Pediatric low-grade tectal gliomas are rare, indolent tumors of the brain stem. We reviewed outcomes of pediatric patients who received a diagnosis of low-grade tectal gliomas and report dosimetric parameters for those receiving radiation therapy (RT).

Methods and Materials

We retrospectively reviewed all pediatric patients (age <18 years) at our institution diagnosed with a low-grade glioma between 1993 and 2020 (n = 288). Twenty-three patients with tectal gliomas were identified. Patients who received RT (n = 8) had detailed dosimetric analyses performed. Doses to critical structures and any resulting toxicities were reviewed. Minimum follow-up was 2 years and complete follow-up was available for all patients.

Results

Twenty-three patients, with a median age of 8.9 years, were included (range, 0.5-16.2 years). At a median follow-up of 7.4 years (range, 2-24 years), all were alive at the end of the study period. Three patients (13%) were treated with upfront RT; none of these patients developed local failure (LF) after a median follow-up of 10.6 years. One patient was treated with upfront chemotherapy with no evidence of progression afterward. Nineteen patients were initially observed after diagnosis and 26% of them (n = 5) experienced local progression. All 5 were treated with salvage RT, with 1 patient requiring further treatment with chemotherapy. Fractionation schedules for patients undergoing upfront or salvage RT included 50.4 Gy in 28 fractions (n = 4), 54 Gy in 30 fractions (n = 2), and 51 Gy in 30 fractions (n = 2). For patients treated after 2007, the gross tumor volume was delineated on a T2 magnetic resonance imaging with an average gross tumor volume-to-planning target volume expansion of 4.5 mm (range, 3-5 mm). Detailed dosimetric parameters were available for all patients treated with RT.

Conclusions

Our review supports the indolent behavior for most tectal gliomas. For the subset of tumors with evidence of progression, modern photon RT results in excellent oncologic outcomes with minimal late effects.

Single exposure to anesthesia/surgery in neonatal mice induces cognitive impairment in young adult mice

BACKGROUND

The effects of a solitary neonatal exposure to anesthesia plus surgery (anesthesia/surgery) on cognitive function and the underlying mechanism in developing brains remains largely undetermined. We, therefore, set out to investigate the impact of single exposure to anesthesia/surgery in neonatal mice.

METHODS

Six-day-old male and female mice received abdominal surgery under 3% sevoflurane plus 50% oxygen for 2 h. The new object recognition (NOR) and Morris water maze (MWM) were used to evaluate cognitive function in young adult mice. Western blot, ELISA and RT-PCR were used to measure levels of NR2B and IL-6 in medial prefrontal cortex and IL-6 in blood of the mice. We employed NR2B siRNA and IL-6 antibody in the interaction studies.

RESULTS

The anesthesia/surgery decreased the ratio of novel time to novel plus familiar time in NOR and the number of platform crossings, but not escape latency, in MWM compared to sham condition. The mice in anesthesia/surgery group had increased NR2B expression in medial prefrontal cortex, and IL-6 amounts in blood and medial prefrontal cortex. Local injection of NR2B siRNA in medial prefrontal cortex alleviated the anesthesia/surgery-induced cognitive impairment. IL-6 antibody mitigated the anesthesia/surgery-induced upregulation of NR2B and cognitive impairment in young adult mice.

CONCLUSIONS

These results suggest that a single neonatal exposure to anesthesia/surgery causes impairment of memory, but not learning, in young adult mice through IL-6-regulated increases in NR2B concentrations in medial prefrontal cortex, highlighting the need for further research on the underlying mechanisms of anesthesia/surgery's impact on cognitive function in developing brains.

General anaesthesia, the developing brain, and cerebral white matter alterations: a narrative review

The potential neurotoxic impact of anaesthetic agents has been the subject of sustained debate and continuing research. White matter, which comprises more than half of the brain volume and largely consists of myelinated axonal bundles, is critical for communication between diverse brain regions and for supporting neurobehavioural function. Evidence points to a correlation between exposure to anaesthesia and white matter alterations, which might underpin the ensuing cognitive and behavioural abnormalities. This review summarises the neuropathological and neuroimaging findings related to anaesthesia-induced white matter alterations in the developing brain. Future research is required to understand the effects of anaesthesia exposure on white matter development.

Cannulation via the external jugular vein--An alternative to conventional peripherally inserted central catheterisation for paediatric patients

PURPOSE

This study aimed to describe a peripherally inserted central catheterisation (PICC) for paediatric patients with inaccessible access and a high risk of general anaesthesia (GA).

METHODS

This was a retrospective observational study involving all paediatric inpatients who performed the PICC via an EJV approach without GA between September 2014 and September 2021 in a provincial key clinical speciality.

RESULTS

A total of 290 EJV line placement attempts were performed, and 29 were excluded due to missing placement results, resulting in a sample size of 261. The anatomical localisation, punctures, and catheterisation success rates for this practice were 100%, 100%, and 90.04%, respectively. The placement success rate in children younger than one year was 93.75% (45/48). The median line duration of use was 19 days, with a median length of catheter insertion of 13 cm. The most common complications were catheter malposition (n = 20) and dislodgement (n = 7).

CONCLUSION

The PICC via an EJV approach without GA is a feasible and safe practice with acceptable success and complication rates, and low costs. It might be an attractive alternative for obtaining central vascular access for paediatric patients.

[Formula: see text] Trajectories of neurodevelopment and opportunities for intervention across the lifespan in congenital heart disease

Children with congenital heart disease (CHD) are at increased risk for neurodevelopmental challenges across the lifespan. These are associated with neurological changes and potential acquired brain injury, which occur across a developmental trajectory and which are influenced by an array of medical, sociodemographic, environmental, and personal factors. These alterations to brain development lead to an array of adverse neurodevelopmental outcomes, which impact a characteristic set of skills over the course of development. The current paper reviews existing knowledge of aberrant brain development and brain injury alongside associated neurodevelopmental challenges across the lifespan. These provide a framework for discussion of emerging and potential interventions to improve neurodevelopmental outcomes at each developmental stage.

Unanswered questions of anesthesia neurotoxicity in the developing brain

PURPOSE OF REVIEW

This article reviews recent advances and controversies of developmental anesthesia neurotoxicity research with a special focus on the unanswered questions in the field both from clinical and preclinical perspectives.

RECENT FINDINGS

Observational cohort studies of prenatal and early childhood exposure to anesthesia have reported mixed evidence of an association with impaired neurodevelopment. Meta-analyses of currently available studies of early childhood exposure to anesthesia suggest that, while limited to no change in general intelligence can be detected, more subtle deficits in specific neurodevelopmental domains including behavior and executive function may be seen. Several studies have evaluated intraoperative blood pressure values and neurocognitive outcomes and have not found an association. Although many animal studies have been performed, taking into consideration other peri-operative exposures such as pain and inflammation may help with translation of results from animal models to humans.

SUMMARY

Advances have been made in the field of developmental anesthetic neurotoxicity over the past few years, including the recognition that anesthetic exposure is associated with deficits in certain cognitive domains but not others. Although the most important question of whether anesthetic agents actually cause long-term neurodevelopmental effects in children has still not been answered, results from recent studies will guide further studies necessary to inform clinical decision-making in children.

Neurobehavioral effects of general anesthesia and cochlear implantation on hearing-impaired infants: A prospective observational cohort study

INTRODUCTION

The potential adverse effects of prolonged exposure to anesthetics in pediatric patients with severe-to-profound sensorineural hearing loss remain unclear. This study aimed to examine whether early bilateral cochlear implantation involving long-duration anesthetic exposure caused greater developmental impairment than that with unilateral cochlear implantation.

METHODS

This prospective observational study included normally developing infants with bilateral severe-to-profound sensorineural hearing loss aged 6 months to 2 years who were candidates for unilateral/bilateral cochlear implantation surgery. Baseline (T0), 6-month (T1), and 1-year (T2) Gesell Scale scores were measured. The outcomes included fine motor, adaptability, gross motor, language, and social skills scale 6 and 12 months postoperatively.

RESULT

The 90 enrolled children with bilateral severe-to-profound sensorineural hearing loss (unilateral n = 43; bilateral n = 47) had a younger bilateral group (11.00 ± 3.66 vs. 15.63 ± 6.99 months, p < .001). Anesthesia duration was longer in the bilateral group (271.57 ± 36.09 vs. 148.81 ± 25.60 min, p < .001). Gross motor, fine motor, adaptability, and language scores improved in both groups, and no significant between-group differences occurred in the fine motor scale at T1 and T2. Language developmental quotients improved significantly in the bilateral group compared with the unilateral group at T1 (mean differences: 25.07 ± 4.37 vs. 10.88 ± 4.61, p < .001) and T2 (mean differences: 34.98 ± 5.94 vs. 15.28 ± 6.55, p < .001). Stepwise regression revealed that gross motor, adaptability, language, and social skill developmental quotients at T1 were positively correlated with those at T0. Gross motor, fine motor, and social skill developmental quotients at T2 were negatively correlated with age at operation. Language developmental quotients were positively correlated with T0 values (p < .001) and in the bilateral group (p < .001) at T1 and T2.

CONCLUSIONS

When evaluating young children with bilateral severe-to-profound sensorineural hearing loss, despite longer exposures to general anesthesia, bilateral cochlear implantations were associated with more improvement in language scores and no differences in other skills compared with those with only unilateral implantation.

Anesthesia and Sedation Exposure and Neurodevelopmental Outcomes in Infants Undergoing Congenital Cardiac Surgery: A Retrospective Cohort Study

BACKGROUND

Children undergoing complex cardiac surgery are exposed to substantial cumulative doses of sedative medications and volatile anesthetics and are more frequently anesthetized with ketamine, compared with healthy children. This study hypothesized that greater exposure to sedation and anesthesia in this population is associated with lower neurodevelopmental scores at 18 months of age.

METHODS

A secondary analysis was conducted of infants with congenital heart disease who participated in a prospective observational study of environmental exposures and neurodevelopmental outcomes to assess the impact of cumulative volatile anesthetic agents and sedative medications. Cumulative minimum alveolar concentration hours of exposure to volatile anesthetic agents and all operating room and intensive care unit exposures to sedative and anesthesia medications were collected before administration of Bayley Scales of Infant and Toddler Development, 3rd edition (Bayley III), at 18 months of age.

RESULTS

The study cohort included 41 (37%) single-ventricle and 69 (63%) two-ventricle patients. Exposures to volatile anesthetic agents, opioids, benzodiazepines, and dexmedetomidine were not associated with abnormal Bayley III scores. At 18-month follow-up, after adjusting for confounders, each mg/kg increase in ketamine exposure was associated with a 0.34 (95% CI, -0.64 to -0.05) point decrease in Bayley III motor scores (P = 0.024).

CONCLUSIONS

Total cumulative exposures to volatile anesthetic agents were not associated with neurodevelopmental impairment in infants with congenital heart disease undergoing various imaging studies and procedures, whereas higher ketamine doses were associated with poorer motor performance.

EDITOR’S PERSPECTIVE

Effects of Early Exposure to Isoflurane on Susceptibility to Chronic Pain Are Mediated by Increased Neural Activity Due to Actions of the Mammalian Target of the Rapamycin Pathway

Patients who have undergone surgery in early life may be at elevated risk for suffering neuropathic pain in later life. The risk factors for this susceptibility are not fully understood. Here, we used a mouse chronic pain model to test the hypothesis that early exposure to the general anesthetic (GA) Isoflurane causes cellular and molecular alterations in dorsal spinal cord (DSC) and dorsal root ganglion (DRG) that produces a predisposition to neuropathic pain via an upregulation of the mammalian target of the rapamycin (mTOR) signaling pathway. Mice were exposed to isoflurane at postnatal day 7 (P7) and underwent spared nerve injury at P28 which causes chronic pain. Selected groups were treated with rapamycin, an mTOR inhibitor, for eight weeks. Behavioral tests showed that early isoflurane exposure enhanced susceptibility to chronic pain, and rapamycin treatment improved outcomes. Immunohistochemistry, Western blotting, and q-PCR indicated that isoflurane upregulated mTOR expression and neural activity in DSC and DRG. Accompanying upregulation of mTOR and rapamycin-reversible changes in chronic pain-associated markers, including N-cadherin, cAMP response element-binding protein (CREB), purinergic P2Y12 receptor, glial fibrillary acidic protein (GFAP) in DSC; and connexin 43, phospho-extracellular signal-regulated kinase (p-ERK), GFAP, Iba1 in DRG, were observed. We concluded that early GA exposure, at least with isoflurane, alters the development of pain circuits such that mice are subsequently more vulnerable to chronic neuropathic pain states.

Update on lasers in pediatric dermatology: how primary care providers can help patients and families navigate appropriate treatment options and timelines

PURPOSE OF REVIEW

The use of lasers in pediatric dermatology is well established, but recent literature has expanded the evidence for specific timelines of treatment. Additionally, new devices and combinations with medical therapy have improved outcomes and treatment options for various conditions.

RECENT FINDINGS

Pulsed dye laser remains the first-line laser for vascular lesions. Recent guidelines support early initiation of laser treatment in port-wine birthmarks to optimize outcomes. For hemangiomas, laser treatment can offer a meaningful addition to oral propranolol therapy. Lasers with shorter wavelengths offer improved outcomes with decreased downtime for pigmented lesions. General anesthesia in the pediatric population continues to be a controversial topic, and the decision to perform laser under general versus topical anesthesia requires discussion with family of risks and benefits.

SUMMARY

Primary care providers can benefit their patients by prompt referral to dermatology for discussion of laser treatment. Port-wine birthmarks require referral in the first weeks of life so that laser treatment can be initiated if appropriate. Although many dermatologic conditions cannot be completely cleared or cured with laser, treatment can offer meaningful outcomes and benefit for patients and families.

Effects of anesthesia exposure on postnatal maturation of white matter in rhesus monkeys

There is increasing concern about the potential effects of anesthesia exposure on the developing brain. The effects of relatively brief anesthesia exposures used repeatedly to acquire serial magnetic resonance imaging scans could be examined prospectively in rhesus macaques. We analyzed magnetic resonance diffusion tensor imaging (DTI) of 32 rhesus macaques (14 females, 18 males) aged 2 weeks to 36 months to assess postnatal white matter (WM) maturation. We investigated the longitudinal relationships between each DTI property and anesthesia exposure, taking age, sex, and weight of the monkeys into consideration. Quantification of anesthesia exposure was normalized to account for variation in exposures. Segmented linear regression with two knots provided the best model for quantifying WM DTI properties across brain development as well as the summative effect of anesthesia exposure. The resulting model revealed statistically significant age and anesthesia effects in most WM tracts. Our analysis indicated there were major effects on WM associated with low levels of anesthesia even when repeated as few as three times. Fractional anisotropy values were reduced across several WM tracts in the brain, indicating that anesthesia exposure may delay WM maturation, and highlight the potential clinical concerns with even a few exposures in young children.

A new view on old problems in paediatric anaesthesia: premedication, postoperative agitation and dosing

PURPOSE OF REVIEW

The aim of this review is to discuss recent developments in paediatric anaesthesia, which have evolved in an undulating fashion.

RECENT FINDINGS

The role and efficacy of pharmacological premedication is reevaluated. The anxiolytic and sedative properties of midazolam and α 2 -agonists have now been defined more precisely. Both classes of drugs have their unique profile, and there is no reason to condemn one or the other. Midazolam is an excellent anxiolytic, whereas dexmedetomidine is superior in the postoperative period and for sedation during diagnostic imaging.A total intravenous technique with propofol is often considered to be the standard for the prevention of emergence agitation; but alternatives do exist, such as a co-medication with dexmedetomidine or opioids. In clinical reality, a multimodal approach may often be advisable.The theoretical basis for propofol dosing has recently been adapted. In contrast to previous beliefs, the context-sensitive half-life of propofol seems to be quite short beyond the first year of life.

SUMMARY

Midazolam and dexmedetomidine are not interchangeable; each compound has its pros and cons. As an anxiolytic drug, midazolam indisputably deserves its place, whereas dexmedetomidine is a better sedative and particularly beneficial in the postoperative period. New data will allow more precise age-adapted dosing of propofol.

Sevoflurane Induces a Cyclophilin D-Dependent Decrease of Neural Progenitor Cells Migration

Clinical studies have suggested that repeated exposure to anesthesia and surgery at a young age may increase the risk of cognitive impairment. Our previous research has shown that sevoflurane can affect neurogenesis and cognitive function in young animals by altering cyclophilin D (CypD) levels and mitochondrial function. Neural progenitor cells (NPCs) migration is associated with cognitive function in developing brains. However, it is unclear whether sevoflurane can regulate NPCs migration via changes in CypD. To address this question, we treated NPCs harvested from wild-type (WT) and CypD knockout (KO) mice and young WT and CypD KO mice with sevoflurane. We used immunofluorescence staining, wound healing assay, transwell assay, mass spectrometry, and Western blot to assess the effects of sevoflurane on CypD, reactive oxygen species (ROS), doublecortin levels, and NPCs migration. We showed that sevoflurane increased levels of CypD and ROS, decreased levels of doublecortin, and reduced migration of NPCs harvested from WT mice in vitro and in WT young mice. KO of CypD attenuated these effects, suggesting that a sevoflurane-induced decrease in NPCs migration is dependent on CypD. Our findings have established a system for future studies aimed at exploring the impacts of sevoflurane anesthesia on the impairment of NPCs migration.

Bicuculline and Bumetanide Attenuate Sevoflurane-Induced Impairment of Myelination and Cognition in Young Mice

Sevoflurane (Sevo) is one of the most commonly used general anesthetics for infants and young children. We investigated whether Sevo impairs neurological functions, myelination, and cognition via the γ-aminobutyric acid A receptor (GABA_AR) and Na⁺-K⁺-2Cl^- cotransporter (NKCC1) in neonatal mice. On postnatal days 5-7, mice were exposed to 3% Sevo for 2 h. On postnatal day 14, mouse brains were dissected, and oligodendrocyte precursor cell line level lentivirus knockdown of GABRB3, immunofluorescence, and transwell migration assays were performed. Finally, behavioral tests were conducted. Multiple Sevo exposure groups exhibited increased neuronal apoptosis levels and decreased neurofilament protein levels in the mouse cortex compared with the control group. Sevo exposure inhibited the proliferation, differentiation, and migration of the oligodendrocyte precursor cells, thereby affecting their maturation process. Electron microscopy revealed that Sevo exposure reduced myelin sheath thickness. The behavioral tests showed that multiple Sevo exposures induced cognitive impairment. GABA_AR and NKCC1 inhibition provided protection against Sevo-induced neurotoxicity and cognitive dysfunction. Thus, bicuculline and bumetanide can protect against Sevo-induced neuronal injury, myelination impairment, and cognitive dysfunction in neonatal mice. Furthermore, GABA_AR and NKCC1 may be mediators of Sevo-induced myelination impairment and cognitive dysfunction.

Practical and societal implications of the potential anesthesia-induced neurotoxicity: The safetots perspective

Key elements for safe and high-quality care in pediatric anesthesia are personal and institutional competence, perioperative maintenance of physiological homeostasis, prevention, prompt recognition, and appropriate treatment of critical situations as well as the reassurance of the parents and respecting the children's rights. Training in pediatric anesthesia should take place within the framework of harmonized curricular structures. International quality assessment and improvement projects should be encouraged and supported by collaborations. Healthy communication and providing information in a balanced way to the public and all stakeholders is an important task for pediatric anesthesia societies and individuals. The Safetots.org initiative was established to emphasize the role of the conduct of anesthesia to prevent harm, promote quality in the perioperative period, and provide safe and high-quality clinical care. This initiative considers that the prevention of complications and other well-known risk factors of perioperative care, as well as the quality of anesthesia management, have a far more important impact on outcomes following anesthesia and surgery than anesthetic drugs themselves.

Localization and Laparoscopic Excision of Gastric Heterotopic Pancreas in a Child by Endoscopic SPOT® Tattooing

Heterotopic pancreas (HP) is defined as pancreatic tissue lacking vascular or anatomic connection with the normal pancreas. Surgical resection is often indicated for symptomatic gastric HP. However, intraoperative identification of gastric HP is often difficult during laparoscopic surgery. Herein, we describe a patient with gastric HP, which was marked with SPOT^® dye (GI Supply, Camp Hill, PA, USA). The dye was seen clearly laparoscopically facilitating total excision of the lesion. The final pathology report confirmed the presence of heterotopic pancreatic tissue including pancreatic acini, small pancreatic ducts tissue with islets of Langerhans in the deep gastric submucosal area. There were no postoperative complications, and the patient was symptom-free. To the best of our knowledge, this was the first case report in the literature in which endoscopic tattooing of gastric HP before laparoscopic resection was performed. This method of localization was simple and reliable in children.

Usefulness of serum neurofilament light in the assessment of neurologic outcome in the pediatric population: a systematic literature review

Children undergoing general anesthesia and surgery in the early years of life are exposed to the possible neurotoxicity of anesthetic agents. Prospective studies have shown deficits in behavior, executive function, social communication, and motor function in children undergoing anesthesia and surgery. Different biomarkers of neuronal injury have been evaluated neuronal injury in the pediatric population, among which neurofilaments represent a significant advantage as they are proteins exclusively expressed in neuronal tissue. Our aim was to evaluate the utility of serum neurofilament light (NfL) as a prognostic biomarker of neuronal injury in the pediatric population. A literature search was performed on PubMed, Embase, and Cochrane Databases in November 2022 for studies concerning serum NfL in the pediatric population in addition to a neurological assessment. Inclusion criteria were as follows: (1) prospective or retrospective studies, (2) studies including pediatric population until the age of 18 years, (3) serum NfL sampling, and (4) evaluation of neurological outcome. Data collection regarding study design, pediatric age, serum NfL levels, and results for neurological assessment were extracted from each study. Four manuscripts met the inclusion criteria and evaluated the prognostic utility of serum NfL in neonatal encephalopathy in correlation with the neurodevelopmental outcome that was assessed by the Bayley Scales of Infant Development until the age of 2 years. Children with neonatal encephalopathy showed significantly higher serum NfL vs. healthy controls and high serum NfL levels predicted an adverse neurological outcome. The decrease of serum NfL to a nadir point between 10 and 15 years old reflects the brain growth in healthy controls. No studies were available in the perioperative period.  Conclusions: Serum NfL is a valuable biomarker in evaluating neuronal injury in the pediatric population. Further studies with perioperative serial sampling of serum NfL combined with standardized neurodevelopmental tests should be conducted to evaluate the neurotoxicity of anesthetic agents and monitor the effectiveness of specific neuroprotective strategies in pediatric patients undergoing anesthesia and surgery. What is Known: • Preclinical animal data have shown neurotoxicity of the anesthetic agents in the developing brain. • Data regarding anesthetic neurotoxicity in humans show limitations and no objective tools are available. What is New: • This systematic review showed that serum NfL is a valuable biomarker of neuronal injury in the pediatric population. • Perioperative use of serum NfL may be considered in future trials evaluating anesthetic neurotoxicity in the pediatric population and in monitoring neuroprotective strategies.

Association of sedation and anesthesia on cognitive outcomes in very premature infants: a retrospective observational study

PURPOSE

Cognitive outcomes in preterm infants may be adversely affected by use of sedation and anesthetic agents. We investigated the associations between anesthetics/sedatives and full-scale intelligence quotient (FSIQ) measured at 36 months corrected age (CA) in very preterm infants (born < 29 weeks gestational age).

METHODS

This retrospective cohort study included preterm infants born at < 29 weeks of gestation between 1 January 2006 and 31 December 2012, whose cognitive outcomes were assessed at 36 months CA. Imputed and complete case univariable and adjusted multivariable linear regressions were used to investigate the associations between FSIQ [standardized to mean (standard deviation) 100 (15)] and exposure to volatile anesthetics, propofol, benzodiazepines, barbiturates, and ketamine. These agents were the subject of a 2016 warning from regulatory authorities in the USA recommending caution for administration to children and pregnant women.

RESULTS

A total of 731 infants met the inclusion criteria. Unadjusted associations were -7 (95% confidence interval [CI], -10 to -4; P < 0.001) and -6 (95% CI, -10 to -3; P < 0.001) FSIQ points with exposure to warned medications using imputed and complete case analyses, respectively. Imputed and complete case adjusted associations between FSIQ and warned medications were -3 (95% CI, -7 to 0; P = 0.045) and -4 (95% CI, -8 to 0; P = 0.071) FSIQ points, respectively. Adjusted associations between volatile anesthetic exposure only and FSIQ were -3 (95% CI, -6 to 0; P = 0.072) and -5 (95% CI, -9 to -2; P = 0.004) FSIQ points using imputed and complete case data sets, respectively. FSIQ was not associated with opioid exposure.

CONCLUSION

Exposure of very preterm infants to anesthetics/sedatives on the United States Food and Drug Administration warning list was associated with a decrease in FSIQ points at 36 months CA. There was no association between opioid exposure and FSIQ.

General Anesthesia and the Premature Baby: Identifying Risks for Poor Neurodevelopmental Outcomes

Preterm birth affects 1 in every 10 infants born in the United States. Importantly, more preterm infants are surviving to discharge from hospital, including those born at the cusp of viability (eg, 22 to 24 wk gestation). Such improvements, however, come at a cost as those delivered at less than 28 weeks gestation have the highest rates of morbidity and mortality. To complicate matters, these extremely preterm infants often require multiple surgical procedures resulting in repeated and prolonged exposures to anesthetic, analgesic, and sedative agents both during procedures and in the neonatal intensive care unit. Consequently, all of these factors, including premature birth itself, correlate with a higher risk for neurodevelopmental disabilities. More studies are needed to address the effects of prematurity-related morbidities and drug exposures on this vulnerable population, with the goal of improving neurodevelopmental outcomes. This brief review will discuss risk factors that impact neurodevelopmental outcomes in premature infants, with a particular focus on anesthetic, analgesic, and sedative agents.

mTORC1-Dependent and GSDMD-Mediated Pyroptosis in Developmental Sevoflurane Neurotoxicity

Developmental sevoflurane exposure leads to neuronal cell death, and subsequent learning and memory cognitive defects. The underlyi\ng mechanism remains to be elucidated. Gasdermin D (GSDMD)-mediated pyroptosis is a form of inflammatory cell death and participates in a variety of neurodegenerative diseases. Several studies illustrated that dysregulation of mTOR activity is involved in pyroptotic cell death. The current study was designed to interrogate the role of GSDMD-mediated pyroptosis and mTOR activity in developmental sevoflurane exposure. We found that inhibition of GSDMD pore formation with Disulfiram (DSF) or Necrosulfonamide (NSA) significantly attenuated sevoflurane neurotoxicity in vitro. In addition, treatment with DSF or NSA also mitigated damage-associated molecular patterns (DAMPs) release and subsequent plasma membrane rupture (PMR) induced by sevoflurane challenge. Further investigation showed that the overactivation of mTOR signaling is involved in sevoflurane induced pyroptosis both in vivo and in vitro. Intriguingly, we found that the DAMPs release and subsequent PMR triggered by developmental sevoflurane priming were compromised by knocking down the expression of mTORC1 component Raptor, but not mTORC2 component Rictor. Moreover, sevoflurane induced pyroptosis could also be restored by suppressing mTOR activity or knocking down the expressions of Ras-related small GTPases RagA or RagC. Finally, administration of DSF or NSA dramatically improved the spatial and emotional cognitive disorders without alternation of locomotor activity. Taken together, these results indicate that mTORC1-dependent and GSDMD-mediated pyroptosis contributes to the developmental sevoflurane neurotoxicity. Characterizing these processes may provide experimental evidence for the possible prevention of developmental sevoflurane neurotoxicity.

Anesthesia and developing brain: What have we learned from recent studies

Anesthesia is unavoidable in surgical procedures. However, whether the general anesthetics are neurotoxic to immature brains remains undefined. Neurodevelopmental impairment induced by anesthesia has been a critical health issue and topic of concern. This review summarizes recent progress made in clinical and preclinical studies to provide useful suggestions and potential therapeutic targets for the protection of the immature brain. On the one hand, clinical researchers continue the debate about the effect of single and multiple exposures to anesthesia on developing brains. On the other hand, preclinical researchers focus on exploring the mechanisms of neurotoxic effects of general anesthesia on immature brains and seeking novel solutions. Rodent models have always been used in preclinical studies, but it is still unclear whether the mechanisms observed in rodent models have clinical relevance. Compared with these models, non-human primates (NHPs) are more genetically similar to humans. However, few research institutions in this area can afford to use NHP models in their studies. One way to address both problems is by combining single-cell sequencing technologies to screen differential gene expression in NHPs and perform in vivo validation in rodents. The mechanism of anesthesia-induced neurotoxicity still requires further elucidation in primates.

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.

Role of GABAA receptor depolarization-mediated VGCC activation in sevoflurane-induced cognitive impairment in neonatal mice

Background

In neonatal mice, anesthesia with sevoflurane depolarizes the GABA Type A receptor (GABAAR), which leads to cognitive impairment. Calcium accumulation in neurons can lead to neurotoxicity. Voltage-gated calcium channels (VGCCs) can increase intracellular calcium concentration under isoflurane and hypoxic conditions. The underlying mechanisms remain largely unknown.

Methods

Six-day-old mice were anesthetized with 3% sevoflurane for 2 h/day for 3 days. The Y-Maze, new object recognition (NOR) test, the Barnes maze test, immunoassay, immunoblotting, the TUNEL test, and Golgi-Cox staining were used to assess cognition, calcium concentration, inflammatory response, GABAAR activation, VGCC expression, apoptosis, and proliferation of hippocampal nerve cells in mice and HT22 cells.

Results

Compared with the control group, mice in the sevoflurane group had impaired cognitive function. In the sevoflurane group, the expression of Gabrb3 and Cav1.2 in the hippocampal neurons increased (p < 0.01), the concentration of calcium ions increased (p < 0.01), inflammatory reaction and apoptosis of neurons increased (p < 0.01), the proliferation of neurons in the DG area decreased (p < 0.01), and dendritic spine density decreased (p < 0.05). However, the inhibition of Gabrb3 and Cav1.2 alleviated cognitive impairment and reduced neurotoxicity.

Conclusions

Sevoflurane activates VGCCs by inducing GABAAR depolarization, resulting in cognitive impairment. Activated VGCCs cause an increase in intracellular calcium concentration and an inflammatory response, resulting in neurotoxicity and cognitive impairment.

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.

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.

Enhanced hippocampal neurogenesis mediated by PGC-1α-activated OXPHOS after neonatal low-dose Propofol exposure

Background

Developing brain is highly plastic and can be easily affected. Growing pediatric usage of anesthetics during painless procedures has raised concerns about the effect of low-dose anesthetics on neurodevelopment. It is urgent to ascertain the neuronal effect of low-dose Propofol, a widely used anesthetic in pediatrics, on developing brains.

Methods

The behavioral tests after neonatal exposure to low-dose/high-dose Propofol in mice were conducted to clarify the cognitive effect. The nascent cells undergoing proliferation and differentiation stage in the hippocampus and cultured neural stem cells (NSCs) were further identified. In addition, single-nuclei RNA sequencing (snRNA-seq), NSCs bulk RNA-seq, and metabolism trials were performed for pathway investigation. Furthermore, small interfering RNA and stereotactic adenovirus injection were, respectively, used in NSCs and hippocampal to confirm the underlying mechanism.

Results

Behavioral tests in mice showed enhanced spatial cognitive ability after being exposed to low-dose Propofol. Activated neurogenesis was observed both in hippocampal and cultured NSCs. Moreover, transcriptome analysis of snRNA-seq, bulk RNA-seq, and metabolism trials revealed a significantly enhanced oxidative phosphorylation (OXPHOS) level in NSCs. Furthermore, PGC-1α, a master regulator in mitochondria metabolism, was found upregulated after Propofol exposure both in vivo and in vitro. Importantly, downregulation of PGC-1α remarkably prevented the effects of low-dose Propofol in activating OXPHOS and neurogenesis.

Conclusions

Taken together, this study demonstrates a novel alteration of mitochondrial function in hippocampal neurogenesis after low-dose Propofol exposure, suggesting the safety, even potentially beneficial effect, of low-dose Propofol in pediatric use.