A Universal Pharmacokinetic Model for Dexmedetomidine in Children and Adults

Using Real-World Data to Externally Evaluate Population Pharmacokinetic Models of Dexmedetomidine in Children and Infants

Dexmedetomidine is a sedative used in both adults and off-label in children with considerable reported pharmacokinetic (PK) interindividual variability affecting drug exposure across populations. Several published models describe the population PKs of dexmedetomidine in neonates, infants, children, and adolescents, though very few have been externally evaluated. A prospective PK dataset of dexmedetomidine plasma concentrations in children and young adults aged 0.01-19.9 years was collected as part of a multicenter opportunistic PK study. A PubMed search of studies reporting dexmedetomidine PK identified five population PK models developed with data from demographically similar children that were selected for external validation. A total of 168 plasma concentrations from 102 children were compared with both population (PRED) and individualized (IPRED) predicted values from each of the five published models by quantitative and visual analyses using NONMEM (v7.3) and R (v4.1.3). Mean percent prediction errors from observed values ranged from -1% to 120% for PRED, and -24% to 60% for IPRED. The model by James et al, which was developed using similar "real-world" data, nearly met the generalizability criteria from IPRED predictions. Other models developed using clinical trial data may have been limited by inclusion/exclusion criteria and a less racially diverse population than this study's opportunistic dataset. The James model may represent a useful, but limited tool for model-informed dosing of hospitalized children.

Absorption pharmacokinetics and feasibility of intranasal dexmedetomidine in patients under general anaesthesia

BACKGROUND

The use of intranasal dexmedetomidine is hampered by a limited understanding of its absorption pharmacokinetics.

METHODS

We examined the pharmacokinetics and feasibility of intranasal dexmedetomidine administered in the supine position to adult patients undergoing general anaesthesia. Twenty-eight patients between 35 and 80 years of age, ASA 1-3 and weight between 50 and 100 kg, who underwent elective unilateral total hip or knee arthroplasty under general anaesthesia were recruited. All patients received 100 μg of intranasal dexmedetomidine after anaesthesia induction. Six venous blood samples (at 0, 5, 15, 45, 60, 240 min timepoints from dexmedetomidine administration) were collected from each patient and dexmedetomidine plasma concentrations were measured. Concentration-time profiles after nasal administration were pooled with earlier data from a population analysis of intravenous dexmedetomidine (n = 202) in order to estimate absorption parameters using nonlinear mixed effects. Peak concentration (CMAX) and time (TMAX) were estimated using simulation (n = 1000) with parameter estimates and their associated variability.

RESULTS

There were 28 adult patients with a mean (SD) age of 66 (8) years and weight of 83 (10) kg. The mean weight-adjusted dose of dexmedetomidine was 1.22 (0.15) μg kg-1. CMAX 0.273 μg L-1 was achieved at 98 min after intranasal administration (TMAX). The relative bioavailability of dexmedetomidine was 80% (95% CI 75-91%). The absorption half-time (TABS = 120 min; 95% CI 90-147 min) was slower than that in previous pharmacokinetic studies on adult patients. Perioperative haemodynamics of all patients remained stable.

CONCLUSIONS

Administration of intranasal dexmedetomidine in the supine position during general anaesthesia is feasible with good bioavailability. This administration method has slower absorption when compared to awake patients in upright position, with consequent concentrations attained after TMAX for several hours.

Pediatric anesthesia in Australia and New Zealand and health inequity among First Nations and Māori children

Australia and New Zealand are two countries in the Southern Pacific region. They share many pediatric anesthesia similarities in terms of medical organizational systems, education, training, and research, however there are important differences between the two nations in relation to geography, the First Nations populations and the history of colonization. While the standards for pediatric anesthesia and the specialty training requirements are set by the Australian and New Zealand College of Anesthetists and the Society for Pediatric Anesthesia in New Zealand and Australia, colonization has created distinct challenges that each nation now faces in order to improve the anesthetic care of its pediatric population. Australia generally has a high standard of living and good access to health care; disparities exist for First Nations People and for those living in rural or remote areas. Two influences have shaped training within New Zealand over the past 40 years; establishment of a national children's hospital in 1990 and, more importantly, acknowledgement that the First Nations people of New Zealand (Māori) have suffered because of failure to recognize their rights consequent to establishing a partnership treaty between Māori and the British Crown in 1840. Health inequities among Māori in New Zealand and First Nations People in Australia have implications for the health system, culturally appropriate approaches to treatment, and the importance of having an appreciation of First Nations people's history and culture, language, family structure, and cultural safety. Trainees in both countries need to be adequately supported in these areas in order for the sub-specialty of pediatric anesthesia to develop further and improve the anesthetic and surgical outcomes of our children.

Physiologically based modeling reveals different risk of respiratory depression after fentanyl overdose between adults and children

Despite a rapid increase in pediatric mortality rate from prescription and illicit opioids, there is limited research on the dose-dependent impact of opioids on respiratory depression in children, the leading cause of opioid-associated death. In this article, we extend a previously developed translational model to cover pediatric populations by incorporating age-dependent pharmacokinetic, pharmacodynamic, and physiological changes compared to adults. Our model reproduced previous perioperative clinical findings that adults and children have similar risk of respiratory depression at the same plasma fentanyl concentration when specific endpoints (minute ventilation, CO2 tension in the blood) were used. However, our model points to a potential caveat that, in a perioperative setting, routine use of mechanical ventilation and supplemental oxygen maintained the blood and tissue oxygen partial pressures in patients and prevented the use of oxygen-related endpoints to evaluate the consequences of respiratory depression. In a community setting when such oxygenation procedures are not immediately available, our model suggests that the higher oxygen demand and reduced cerebrovascular reactivity could make children more susceptible to severe hypoxemia and brain hypoxia, even with the same plasma fentanyl concentration as adults. Our work indicates that when developing intervention strategies to protect children from opioid overdose in a community setting, these pediatric-specific factors may need to be considered.

Preliminary pharmacokinetics and patient experience of jet-injected dexmedetomidine in healthy adults

Jet injection is a drug delivery system without a needle. A compressed liquid drug formulation pierces the skin, depositing the drug into the subcutaneous or intramuscular tissues. We investigated the pharmacokinetics and patient experience of dexmedetomidine administered using jet injection in six healthy adult study participants. This needleless jet injection device was used to administer dexmedetomidine 0.5 μg/kg to the subcutaneous tissues overlying the deltoid muscle. Serum concentrations of dexmedetomidine were assayed at approximately 5 minutes, 15 minutes, 30 minutes, 1 hour and 4 hours after administration. Pharmacokinetic interrogation of concentration time profiles estimated an absorption half time for jet-injected dexmedetomidine of 21 minutes (coefficient of variation 69.4%) with a relative bioavailability assumed unity. In our samples the measured median peak (range) concentration was 0.164 μg/l (0.011-0.325 μg/l), observed in the sample taken at a median (range) of 13.5 minutes (11-30 minutes). The Richmond agitation sedation scale was used to assess the sedative effect, and scored 0 (alert and calm) or -1 (drowsy) in all participants. Five of the six participants stated they would prefer jet injection to needle injection in the future and one had no preference. The findings suggest that the use of a larger dose (>2 μg/kg) would be required to achieve the clinically relevant target concentration of 1 μg/l necessary to achieve deeper sedation (Richmond agitation sedation scale ≤3).

Pharmacokinetic pharmacodynamic modeling of analgesics and sedatives in children

Pharmacokinetic pharmacodynamic modeling is an important tool which uses statistical methodology to provide a better understanding of the relationship between concentration and effect of drugs such as analgesics and sedatives. Pharmacokinetic pharmacodynamic models also describe between-subject variability that allows identification of subgroups and dose adjustment for optimal pain management in individual patients. This approach is particularly useful in the pediatric population, where most drugs have received limited evaluation and dosing is extrapolated from adult practice. In children, the covariates of weight and age are used to describe size- and maturation-related changes in pharmacokinetics. It is important to consider both size and maturation in order to develop an accurate model and determine the optimal dose for different age groups. An adequate assessment of analgesic and sedative effect using pain scales or brain activity measures is essential to build reliable pharmacokinetic pharmacodynamic models. This is often challenging in children due to the multidimensional nature of pain and the limited sensitivity and specificity of some measurement tools. This review provides a summary of the pharmacokinetic and pharmacodynamic methodology used to describe the dose-concentration-effect relationship of analgesics and sedation in children, with a focus on the different pharmacodynamic endpoints and the challenges of pharmacodynamic modeling.

Anesthesia management of neonates and infants requiring intraoperative neurophysiological monitoring: A concise review

Intraoperative neurophysiological monitoring is currently used to prevent intraoperative spinal cord and nerve injuries during neonatal and infant surgeries. However, its use is associated with some issues in these young children. The developing nervous system of infants and neonates requires higher stimulation voltage than adults to ensure adequate signals, thereby necessitating reduced anesthesia dose to avoid suppressing motor and somatosensory-evoked potentials. Excessive dose reduction, however, increases the risk of unexpected body movement when used without neuromuscular blocking drugs. Most recent guidelines for older children and adults recommend total intravenous anesthesia with propofol and remifentanil. However, the measurement of anesthetic depth is less well understood in infants and neonates. Size factors and physiological maturation cause pharmacokinetics differences compared with adults. These issues make neurophysiological monitoring in this young population a challenge for anesthesiologists. Furthermore, monitoring errors such as false-negative results immediately affect the prognosis of motor and bladder-rectal functions in patients. Therefore, anesthesiologists need to be familiar with the effects of anesthetics and age-specific neurophysiological monitoring challenges. This review provides an update regarding available anesthetic options and their target concentration in neonates and infants requiring intraoperative neurophysiological monitoring.

Pharmacokinetics of dexmedetomidine in pediatric patients undergoing cardiac surgery with cardiopulmonary bypass

BACKGROUND

Cardiopulmonary bypass can affect the pharmacokinetics of anesthetic agents.

AIMS

We aimed to evaluate the pharmacokinetics of dexmedetomidine for infants and small children undergoing cardiac surgery with cardiopulmonary bypass based on population pharmacokinetics.

METHODS

We enrolled 30 pediatric cardiac surgical patients in this study. After anesthetic induction with atropine (0.02 mg/kg), thiopental sodium (5 mg/kg), and fentanyl (2-3 μg/kg), we administered 1 μg/kg of dexmedetomidine for 10 min, followed by administration of 0.5 μg/kg of dexmedetomidine per hour during surgery. At the initiation of cardiopulmonary bypass, 1 μg/kg of dexmedetomidine was infused over 5 min. Arterial blood was obtained at predefined time points. A pharmacokinetic model was developed using NONMEM. Theory-based allometric scaling with fixed exponents was applied. Weight, age, post-menstrual age, fat-free mass, whether to implement cardiopulmonary bypass and temperature were explored as covariates.

RESULTS

A total of 376 blood samples were obtained from 29 children (age: 20.3 ± 19.3 months, weight: 9.7 ± 4.1 kg). A two-compartment mammillary model with third compartment associated cardiopulmonary bypass procedure best explained the pharmacokinetics of dexmedetomidine. The pharmacokinetic parameter estimates (95% CI) standardized to a 70-kg person were as follows: V₁ (L) = 31.6 (17.9-39.5), V₂ (L) = 90.1 (44.0-330), Cl (L/min) = 1.08 (0.70-1.25), Q (L/min) = 2.0 (1.05-3.46). Volume for third compartment associated cardiopulmonary bypass procedure (L) = 39.4 (19.3-50.9). Clearance was not influenced by the presence of cardiopulmonary bypass in this model.

CONCLUSION

When cardiopulmonary bypass is applied, the plasma concentration of dexmedetomidine decreases due to an increase in the volume of distribution, so a loading dose is required to maintain the previous concentration.

Considerations for Intravenous Anesthesia Dose in Obese Children: Understanding PKPD

The intravenous induction or loading dose in children is commonly prescribed per kilogram. That dose recognizes the linear relationship between volume of distribution and total body weight. Total body weight comprises both fat and fat-free mass. Fat mass influences the volume of distribution and the use of total body weight fails to recognize the impact of fat mass on pharmacokinetics in children. Size metrics alternative to total body mass (e.g., fat-free and normal fat mass, ideal body weight and lean body weight) have been proposed to scale pharmacokinetic parameters (clearance, volume of distribution) for size. Clearance is the key parameter used to calculate infusion rates or maintenance dosing at steady state. Dosing schedules recognize the curvilinear relationship, described using allometric theory, between clearance and size. Fat mass also has an indirect influence on clearance through both metabolic and renal function that is independent of its effects due to increased body mass. Fat-free mass, lean body mass and ideal body mass are not drug specific and fail to recognize the variable impact of fat mass contributing to body composition in children, both lean and obese. Normal fat mass, used in conjunction with allometry, may prove a useful size metric but computation by clinicians for the individual child is not facile. Dosing is further complicated by the need for multicompartment models to describe intravenous drug pharmacokinetics and the concentration effect relationship, both beneficial and adverse, is often poorly understood. Obesity is also associated with other morbidity that may also influence pharmacokinetics. Dose is best determined using pharmacokinetic-pharmacodynamic (PKPD) models that account for these varied factors. These models, along with covariates (age, weight, body composition), can be incorporated into programmable target-controlled infusion pumps. The use of target-controlled infusion pumps, assuming practitioners have a sound understanding of the PKPD within programs, provide the best available guide to intravenous dose in obese children.

Justification Of Empiric Methodology to Determine Dexmedetomidine Dose for the TREX Study

INTRODUCTION

Dexmedetomidine is the sedative agent administered in combination with remifentanil and low dose of sevoflurane in the interventional arm of the ongoing TREX trial (Trial Remifentanil DExmedetomidine). The TREX pilot study (published in Paediatr Anaesth 2019;29:59-67) established infusion rates higher than those initially proposed. This could be attributed to an inappropriate target concentration for sedation or incorrect initial pharmacokinetic parameter estimates.

METHODS

The TREX study is a Phase III, randomized, active controlled, parallel group, blinded evaluator, multicentre, superiority trial comparing neurological outcome after standard sevoflurane anaesthesia with dexmedetomidine/remifentanil and low dose sevoflurane anaesthesia in children aged less than 2 years undergoing anaesthesia of 2 hours or longer. In this report, dexmedetomidine pharmacokinetics were analysed in the interventional arm of the Italian population.

RESULTS

There were 162 blood samples from 32 infants (22 male and 10 female). The median (IQR) age was 12 (5.2-15.5) months, weight 9.9 (7.3-10.8) kg. Duration of anaesthesia ranged from 2-6 hours. None of the children were born premature (median postnatal age 39 weeks, IQR 38-40 weeks). A 3-compartment PK model that incorporated allometric scaling and a maturation function demonstrated plasma concentration observations from the current Italian arm of the TREX study were consistent with those predicted by a "universal" model using pooled data obtained from neonates to adults.

CONCLUSIONS

This current PK analysis from the Italian arm of the TREX study confirms that plasma concentration of dexmedetomidine is predictable using known covariates such as age and size. The initial target concentration (0.6 μg.L-1 ) used to sedate children cared for in the intensive care after cardiac surgery was inadequate for infants in the current TREX study. A target concentration 1 mcg.L-1 , corresponding to a loading dose of 1 mcg.kg-1 followed by an infusion of 1 mcg.kg-1 .hour-1 , provided adequate sedation.

Interactions of the protease inhibitor, ritonavir, with common anesthesia drugs

The protease inhibitor, ritonavir, is a strong inhibitor of CYP 3A. The drug is used for management of the human immunovirus and is currently part of an oral antiviral drug combination (nirmatrelvir-ritonavir) for the early treatment of SARS-2 COVID-19-positive patients aged 12 years and over who have recognized comorbidities. The CYP 3A enzyme system is responsible for clearance of numerous drugs used in anesthesia (e.g., alfentanil, fentanyl, methadone, rocuronium, bupivacaine, midazolam, ketamine). Ritonavir will have an impact on drug clearances that are dependent on ritonavir concentration, anesthesia drug intrinsic hepatic clearance, metabolic pathways, concentration-response relationship, and route of administration. Drugs with a steep concentration-response relationship (ketamine, midazolam, rocuronium) are mostly affected because small changes in concentration have major changes in effect response. An increase in midazolam concentration is observed after oral administration because CYP 3A in the gastrointestinal wall is inhibited, causing a large increase in relative bioavailability. Fentanyl infusion may be associated with a modest increase in plasma concentration and effect, but the large between subject variability of pharmacokinetic and pharmacodynamic concentration changes suggests it will have little impact on an individual patient, especially when used with adverse effect monitoring. It has been proposed that drugs that have no or only a small metabolic pathway involving the CYP 3A enzyme be used during anesthesia, for example, propofol, atracurium, remifentanil, and the volatile agents. That anesthesia approach denies children of drugs with considerable value. It is better that the inhibitory changes in clearance of these drugs are understood so that rational drug choices can be made to tailor drug use to the individual patient. Altered drug dose, anticipation of duration of effect, timing of administration, use of reversal agents and perioperative monitoring would better behoove children undergoing anesthesia.

Pharmacokinetic Pharmacodynamic Modelling Contributions to Improve Paediatric Anaesthesia Practice

The use of pharmacokinetic-pharmacodynamic models has improved anaesthesia practice in children through a better understanding of dose-concentration-response relationships, developmental pharmacokinetic changes, quantification of drug interactions and insights into how covariates (e.g., age, size, organ dysfunction, pharmacogenomics) impact drug prescription. Simulation using information from these models has enabled the prediction and learning of beneficial and adverse effects and decision-making around clinical scenarios. Covariate information, including the use of allometric size scaling, age and consideration of fat mass, has reduced population parameter variability. The target concentration approach has rationalised dose calculation. Paediatric pharmacokinetic-pharmacodynamic insights have led to better drug delivery systems for total intravenous anaesthesia and an expectation about drug offset when delivery is stopped. Understanding concentration-dependent adverse effects have tempered dose regimens. Quantification of drug interactions has improved the understanding of the effects of drug combinations. Repurposed drugs (e.g., antiviral drugs used for COVID-19) within the community can have important effects on drugs used in paediatric anaesthesia, and the use of simulation educates about these drug vagaries.

General Purpose Pharmacokinetic-Pharmacodynamic Models for Target-Controlled Infusion of Anaesthetic Drugs: A Narrative Review

Target controlled infusion (TCI) is a clinically-available and widely-used computer-controlled method of drug administration, adjusting the drug titration towards user selected plasma- or effect-site concentrations, calculated according to pharmacokinetic-pharmacodynamic (PKPD) models. Although this technology is clinically available for several anaesthetic drugs, the contemporary commercialised PKPD models suffer from multiple limitations. First, PKPD models for anaesthetic drugs are developed using deliberately selected patient populations, often excluding the more challenging populations, such as children, obese or elderly patients, of whom the body composition or elimination mechanisms may be structurally different compared to the lean adult patient population. Separate PKPD models have been developed for some of these subcategories, but the availability of multiple PKPD models for a single drug increases the risk for invalid model selection by the user. Second, some models are restricted to the prediction of plasma-concentration without enabling effect-site controlled TCI or they identify the effect-site equilibration rate constant using methods other than PKPD modelling. Advances in computing and the emergence of globally collected databases has allowed the development of new “general purpose” PKPD models. These take on the challenging task of identifying the relationships between patient covariates (age, weight, sex, etc) and the volumes and clearances of multi-compartmental pharmacokinetic models applicable across broad populations from neonates to the elderly, from the underweight to the obese. These models address the issues of allometric scaling of body weight and size, body composition, sex differences, changes with advanced age, and for young children, changes with maturation and growth. General purpose models for propofol, remifentanil and dexmedetomidine have appeared and these greatly reduce the risk of invalid model selection. In this narrative review, we discuss the development, characteristics and validation of several described general purpose PKPD models for anaesthetic drugs.

Propofol context-sensitive decrement times in children

Plasma drug concentration is the variable linking dose to effect. The decrement time required for plasma concentration of anesthetic agents to decrease by 50% (context-sensitive half-time) correlates with the time taken to regain consciousness. However, the decrement time to consciousness may not be 50%. An effect compartment concentration is associated more closely with return of consciousness than plasma concentration. An alternative decrement time, the time required for propofol to decrease to a predetermined effect compartment concentration associated with movement (eg, 2 µg.ml^-1 ), was used to simulate time for the concentration to decrease from steady state at a typical targeted effect compartment concentration 3.5 µg.ml^-1 in children. These times were short and reflected a decrement time to consciousness (CST_AWAKE ) increase that was small with longer infusion time. CST_AWAKE ranged from 7.5 min in 1-year-old infant given propofol for 15 min to 13.5 min in a 15-year-old adolescent given a 2-hour infusion. Changes in decrement time with age reflect maturation of drug clearance. Neonates had prolonged increment times, 10 min after 15 min infusion and 18 min after 120 min infusion using a target concentration of 3.5 µg.ml^-1 . Decrement times to a targeted arousal concentration are context-sensitive. Use of a higher target concentration of 6 µg.ml^-1 doubled decrement times. Decrement times are associated with variability: delayed recovery beyond these simulated times is likely more attributable to the use of adjuvant drugs or the child's clinical status. An understanding of propofol decrement times can be used to guide recovery after anesthesia.

Population Pharmacokinetic Analysis of Dexmedetomidine in Children using Real World Data from Electronic Health Records and Remnant Specimens

AIM

Our objectives were to perform a population pharmacokinetic analysis of dexmedetomidine in children using remnant specimens and electronic health records (EHRs) and explore the impact of patient's characteristics and pharmacogenetics on dexmedetomidine clearance.

METHODS

Dexmedetomidine dosing and patient data were gathered from EHRs and combined with opportunistically sampled remnant specimens. Population pharmacokinetic models were developed using nonlinear mixed-effects modeling. Stage one developed a model without genotype variables; Stage two added pharmacogenetic effects.

RESULTS

Our final study population included 354 post-cardiac surgery patients age 0 to 22 years (median 16 months). The data were best described with a two-compartment model with allometric scaling for weight and Hill maturation function for age. Population parameter estimates and 95% confidence intervals were 27.3 L/hr (24.0 - 31.1 L/hr) for total clearance (CL), 161 L (139 - 187 L) for central compartment volume of distribution (V₁ ), 26.0 L/hr (22.5 - 30.0 L/hr) for intercompartmental clearance (Q), and 7903 L (5617 - 11119 L) for peripheral compartment volume of distribution (V₂ ). The estimate for postmenstrual age when 50% of adult clearance is achieved was 42.0 weeks (41.5 - 42.5 weeks) and the Hill coefficient estimate was 7.04 (6.99 - 7.08). Genotype was not statistically or clinically significant.

CONCLUSION

Our study demonstrates the use of real-world EHR data and remnant specimens to perform a population PK analysis and investigate covariate effects in a large pediatric population. Weight and age were important predictors of clearance. We did not find evidence for pharmacogenetic effects of UGT1A4 or UGT2B10 genotype or CYP2A6 risk score.

Pharmacokinetic concepts for dexmedetomidine target-controlled infusion pumps in children

Pharmacokinetic parameter estimates are used in mathematical equations (pharmacokinetic models) to describe concentration changes with time in a population and are specific to that population. Simulation using these models and their parameter estimates can enrich understanding of drug behavior and serve as a basis for study design. Pharmacokinetic concepts are presented pertaining to future designs of dexmedetomidine target-controlled infusion pumps in children. This manuscript provides the pediatric anesthesiologist with an understanding of the nuances that should be considered when using target-controlled infusion pumps; how the central volume may differ between populations, how clearance changes with age, and the impact of adverse effects on dose. In addition, the ideal loading dose and rate of delivery to achieve target concentration without adverse cardiovascular effects are reviewed, and finally, dose considerations for obese children, based on contact-sensitive half-time, are introduced. An understanding of context-sensitive half-time changes with age enables anesthetic practitioners to better estimate duration of effect after cessation of dexmedetomidine infusion. Use of these known pharmacokinetic parameters and covariate information for the pediatric patient could readily be incorporated into commercial target-controlled infusion pumps to allow effective and safe open-loop administration of dexmedetomidine in children.

A decade later, there are still major issues to be addressed in paediatric anaesthesia

PURPOSE OF REVIEW

Despite real advances in paediatric anaesthesia management, such as a growing awareness of the relevance of anaesthesia conduct as well as of the lack of evidence for neurotoxicity of anaesthetic agents, it must be said that there are still important questions in our specialty that remain unanswered. Standardization and harmonization of airway management, analgesia techniques and outcome measures are the important issues we are facing at the beginning of this decade.

RECENT FINDINGS

Major improvements in airway management of neonates and infants resulted from the introduction of videolaryngoscopes and the systematic use of nasal oxygenation during endotracheal intubation. Similarly, the increasing popularity of dexmedetomidine has led to the generalization of its use, which, considering that it may produce undesirable effects, poses a challenge for the future. Moreover, recent systematic reviews have confirmed a lack of evidence for the efficacy of many techniques used in clinical practice.

SUMMARY

The shift in research from the neurotoxicity of anaesthetic agents to factors related to anaesthetic conduct are discussed. Examples for an improvement in anaesthesia management are highlighted with advocacy for including these evidence-based findings in routine clinical practice. Finally, the impact of using clinically relevant age-related and patient-centred perioperative outcomes is essential for comparing and/or interpreting the safety and efficacy of anaesthesia and analgesia management in children.