Report on the Sixth Pediatric Anesthesia Neurodevelopmental Assessment (PANDA) Symposium, "Anesthesia and Neurodevelopment in Children"

Repeated Ketamine Anesthesia during the Neonatal Period Impairs Hippocampal Neurogenesis and Long-Term Neurocognitive Function by Inhibiting Mfn2-Mediated Mitochondrial Fusion in Neural Stem Cells

The mechanism of ketamine-induced neurotoxicity development remains elusive. Mitochondrial fusion/fission dynamics play a critical role in regulating neurogenesis. Therefore, this study was aimed to evaluate whether mitochondrial dynamics were involved in ketamine-induced impairment of neurogenesis in neonatal rats and long-term synaptic plasticity dysfunction. In the in vivo study, postnatal day 7 (PND-7) rats received intraperitoneal (i.p.) injection of 40 mg/kg ketamine for four consecutive times at 1 h intervals. The present findings revealed that ketamine induced mitochondrial fusion dysfunction in hippocampal neural stem cells (NSCs) by downregulating Mitofusin 2 (Mfn2) expression. In the in vitro study, ketamine treatment at 100 μM for 6 h significantly decreased the Mfn2 expression, and increased ROS generation, decreased mitochondrial membrane potential and ATP levels in cultured hippocampal NSCs. For the interventional study, lentivirus (LV) overexpressing Mfn2 (LV-Mfn2) or control LV vehicle was microinjected into the hippocampal dentate gyrus (DG) 4 days before ketamine administration. Targeted Mfn2 overexpression in the DG region could restore mitochondrial fusion in NSCs and reverse the inhibitory effect of ketamine on NSC proliferation and its faciliatory effect on neuronal differentiation. In addition, synaptic plasticity was evaluated by transmission electron microscopy, Golgi-Cox staining and long-term potentiation (LTP) recordings at 24 h after the end of the behavioral test. Preconditioning with LV-Mfn2 improved long-term cognitive dysfunction after repeated neonatal ketamine exposure by reversing the inhibitory effect of ketamine on synaptic plasticity in the hippocampal DG. The present findings demonstrated that Mfn2-mediated mitochondrial fusion dysfunction plays a critical role in the impairment of long-term neurocognitive function and synaptic plasticity caused by repeated neonatal ketamine exposure by interfering with hippocampal neurogenesis. Thus, Mfn2 might be a novel therapeutic target for the prevention of the developmental neurotoxicity of ketamine.

Computed Analysis of Retinal Vascular Growth After Bevacizumab Treatment of Retinopathy of Prematurity Until Age 3 Years

PURPOSE

Premature infants, after anti-vascular endothelial growth factor injections for retinopathy of prematurity, have persistent peripheral avascular retina (PAR). PAR is ablated with laser; however, physiologic growth of the retinal vasculature in the long term has not been measured. The purposes of this study were to measure retinal vessel growth after treatment with intravitreal bevacizumab (IVB) for retinopathy of prematurity, using serial fluorescein angiography (FA), until age 3 years, and to assess the timing for providing laser ablation in PAR.

METHODS

Data from an observational, longitudinal clinical study were collected. Angiographic images of eyes treated with IVB were included; imaging data from laser photocoagulation were excluded. All eyes underwent initial examination under general anesthesia with FA and photographic imaging. The retinal vessel length was measured from the temporal margin of the optic disc passing through the foveal center, and the lengths at subsequent FA were compared. To compare the changes in retinal vessel length over time in individual eyes, a paired-sample t test was performed.

FINDINGS

FA images from 70 eyes (35 infants) treated with IVB were available. A total of 150 FA images were available for review; data from 125 images of good quality were used for analysis. The mean postmenstrual ages (PMAs) at first, second, third, and fourth FA were 66.2, 100.9, 135.1, and 180.7 weeks, respectively. The mean retinal vessel length was 14.177 mm at first FA and 13.199 mm at fourth FA (PMA range, 42...234 weeks). Retinal vascular lengths of individual eyes compared over time showed no statistically significant growth from the first FA to age 3 years. The changes in retinal vessel length from first to second FA were -0.117 ± 0.79 mm (p = 0.42; n = 30); from first to third FA, +0.060 ± 0.85 mm (p = 0.79; n = 15); and first to fourth FA, -0.404 ± 1.32 mm (p = 0.45; n = 7).

IMPLICATIONS

Beyond 65 weeks' PMA, no meaningful retinal vascular growth occurred after IVB up to age 3 years, guiding the timing for physicians if laser photocoagulation is being considered. Future studies are needed to address retinal growth changes in the growing eyes of infants.

Ketamine-induced neurotoxicity in neurodevelopment: A synopsis of main pathways based on recent in vivo experimental findings

Ketamine, a phencyclidine derivative and N-methyl-D-aspartate (NMDA) receptor antagonist, is widely used as an anesthetic, analgesic, and sedative agent in daily pediatric practice. Experimental studies have suggested that early prenatal or postnatal exposure to ketamine can induce neuroapoptosis, and establish neurobehavioral deficits that are evident in adulthood. However, most of the currently available clinical evidence is derived from retrospective and observational clinical studies. We, herein, attempt a brief review of the cellular and molecular mechanisms suggested to mediate ketamine-induced developmental neurotoxicity, utilizing a selected number of recent in vivo experimental evidence.

A Cross-Sectional Analysis of Community Water Fluoridation and Prevalence of Pediatric Dental Surgery Among Medicaid Enrollees

IMPORTANCE

Dental surgery under general anesthesia (DGA) is an ineffective, costly treatment for caries. Interventions to reduce the need for DGA are challenging because children's parents may not seek care until surgery is required. Community water fluoridation (CWF) effectively prevents early childhood caries, but its effectiveness in reducing severe early childhood caries is unknown.

OBJECTIVE

To determine whether access to CWF is associated with the prevalence of DGA.

DESIGN, SETTING, AND PARTICIPANTS

This is a cross-sectional analysis of Medicaid claims data from 2011 to 2012. Deidentified data were derived from Medicaid claims and enrollee files for Massachusetts, Texas, Connecticut, Illinois, and Florida for children aged 9 years and younger enrolled in either a fee-for-service or managed care plan through their state's Medicaid program. Linear regression models tested for associations between CWF and covariates. Multivariable linear regression models tested for associations between CWF and outcomes. Regression models included clustered SEs at the county level. Data analysis was performed from December 2018 to March 2020.

EXPOSURES

Access to CWF was determined by estimating the proportion of a county's total population that had access to a fluoridated public water system.

MAIN OUTCOMES AND MEASURES

The main outcome was county-level DGA prevalence. Other outcomes were caries-related visit prevalence and patient quality indicators (asthma and diabetes). Covariates included county-level demographic, socioeconomic, and dental practitioner variables.

RESULTS

A total of 436 counties within 5 states per year (872 county-year observations), were included in the analysis. Adjusted analysis revealed that a 10% increase in the proportion of county's population access to CWF was associated with lower caries-related visit prevalence (-0.45 percentage points; 95% CI, -0.59 to -0.31 percentage points; P < .001). Increasing CWF access in 10% increments was associated with decreased DGA prevalence in unadjusted analysis (-0.39 percentage points; 95% CI, -0.67 to -0.12 percentage points; P = .006) but not in adjusted analysis (-0.23 percentage points; 95% CI, -0.49 to 0.02 percentage points; P = .07). Increasing the proportion of county's access to CWF by 10% was not associated with the prevalence of asthma-related exacerbations (-0.02 percentage points; 95% CI, -0.10 to 0.05 percentage points; P = .53) or diabetes-related exacerbations (-0.0003 percentage points; 95% CI, -0.0014 to 0.0009 percentage points; P = .66).

CONCLUSIONS AND RELEVANCE

This study extends our understanding of CWF's benefits for children's oral health. Specifically, these findings suggest that increasing a population's access to CWF's is associated with decreased caries-related visits and may also be associated with use of dental surgical services within high-risk populations.

Cleft Palate Repair: A New Maxillary Nerve Block Approach

OBJECTIVE

To introduce a different approach for maxillary nerve block (MNB), in cleft palate repair. To reduce the use of opioids during surgery and to prevent frequent respiratory complications by means of an adequate intra and postoperative pain relief.

PATIENTS AND METHODS

A prospective clinical trial was planned, to collect scientific evidences between 2 groups of patients with primary cleft palate, receiving surgery in 2 Pediatric centers of Buenos Aires, utilizing a different protocol.Sixty patients undergoing primary cleft palate repair in both hospitals, from January 2017 to July 2018, by senior surgeons and the same expert anesthesiologists' team, were included.Syndromic and secondary cases, and patients whose parents rejected to participate of this study were excluded. The first group called Hospital A included 45 children, the second group identified as Hospital B was formed by 15 patients.A combination of general whit local anesthesia and a bilateral regional MNB, was used in all the patients of the Hospital A. Utilizing an aspirating syringe, children received 0.15 ml/kg of lidocaine clorhidrate 2% with epinephrine 1:50.000, under direct vision through the spheno palatine holes, just before surgery. A traditional general anesthesia procedure plus local anesthesia, was utilized in all the patients treated at the Hospital B Medial blood pressure and cardiac frequency parameters were tested during induction, along the surgical procedure and in the immediate post op, to detect any sign of pain (12). After surgery, patient reactivity, airway depression symptoms, time of initial feeding and discharge time, were also monitored (13).This study was approved by the Hospitals Ethics Committees of both hospitals, and is in accordance with the 1975 Helsinki Declaration, as amended in 1983. The parents have signed an informed consent form for all the patients included.

RESULTS

Patients of both groups did not show any significant variant in the monitored parameters to detect signals of pain, along the surgery. The rest of controls during and after surgery showed significant differences in favor of the patients of Hospital A.

CONCLUSIONS

Bilateral regional MNB, under direct vision trough the spheno palatine holes results an effective, easy, and safe method for pain relief during and after primary cleft palate repair surgeries.The combination of slight general anesthesia with local anesthesia and regional blocks, results a good option to reduce opioids utilization, to prevent neurotoxicity, respiratory depression, sickness, and vomiting facilitating early feeding and patient discharge.

Inguinal Hernia in Premature Infants

Inguinal hernia is a common problem affecting infants in the NICU. As a group, preterm infants have the highest incidence of inguinal hernia and this risk increases as gestational age decreases. The etiopathologic factors leading to the development of an inguinal hernia are not clear and interventions to alter these factors have not been thoroughly investigated. Diagnosis of an inguinal hernia is often straightforward, but occasionally it may be difficult to determine if the hernia is strangulated or simply obstructed. Rarely, investigative modalities, such as ultrasonography, may be needed to rule out other potential causes. The ideal timing of surgical repair in this population is unknown and complicated by comorbid conditions and limited randomized controlled trials. During surgery, the choice of regional versus general anesthesia requires a team-based approach and studies have found that greater clinical experience is associated with lower morbidity. The techniques of hernia surgery range from open to laparoscopic repair and have been investigated in small prospective studies, while larger databases have been used to analyze outcomes retrospectively.

Neuroanesthesiology Update

This review is intended to provide a summary of the literature pertaining to the perioperative care of neurosurgical patients and patients with neurological diseases. General topics addressed in this review include general neurosurgical considerations, stroke, neurological monitoring, and perioperative disorders of cognitive function.