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Azimaraghi O, Rudolph MI, Luedeke CM, Ramishvili T, Jaconia GD, Scheffenbichler FT, Chambers TA, Karaye IM, Eikermann M, Chao J, Jackson WM. Association of dexmedetomidine use with haemodynamics, postoperative recovery, and cost in paediatric anaesthesia: a hospital registry study. Br J Anaesth 2024; 133:326-333. [PMID: 38631942 DOI: 10.1016/j.bja.2024.03.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 03/15/2024] [Accepted: 03/22/2024] [Indexed: 04/19/2024] Open
Abstract
BACKGROUND Dexmedetomidine utilisation in paediatric patients is increasing. We hypothesised that intraoperative use of dexmedetomidine in children is associated with longer postanaesthesia care unit length of stay, higher healthcare costs, and side-effects. METHODS We analysed data from paediatric patients (aged 0-12 yr) between 2016 and 2021 in the Bronx, NY, USA. We matched our cohort with the Healthcare Cost and Utilization Project-Kids' Inpatient Database (HCUP-KID). RESULTS Among 18 104 paediatric patients, intraoperative dexmedetomidine utilisation increased from 51.7% to 85.7% between 2016 and 2021 (P<0.001). Dexmedetomidine was dose-dependently associated with a longer postanaesthesia care unit length of stay (adjusted absolute difference [ADadj] 19.7 min; 95% confidence interval [CI]: 18.0-21.4 min; P<0.001, median length of stay of 122 vs 98 min). The association was magnified in children aged ≤2 yr undergoing short (≤60 min) ambulatory procedures (ADadj 33.3 min; 95% CI: 26.3-40.7 min; P<0.001; P-for-interaction <0.001). Dexmedetomidine was associated with higher total hospital costs of USD 1311 (95% CI: USD 835-1800), higher odds of intraoperative mean arterial blood pressure below 55 mm Hg (adjusted odds ratio [ORadj] 1.27; 95% CI: 1.16-1.39; P<0.001), and higher odds of heart rate below 100 beats min-1 (ORadj 1.32; 95% CI: 1.21-1.45; P<0.001), with no preventive effects on emergence delirium requiring postanaesthesia i.v. sedatives (ORadj 1.67; 95% CI: 1.04-2.68; P=0.034). CONCLUSIONS Intraoperative use of dexmedetomidine is associated with unwarranted haemodynamic effects, longer postanaesthesia care unit length of stay, and higher costs, without preventive effects on emergence delirium.
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Affiliation(s)
- Omid Azimaraghi
- Department of Anesthesiology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Maíra I Rudolph
- Department of Anesthesiology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA; University of Cologne, Faculty of Medicine and University Hospital Cologne, Department for Anesthesiology and Intensive Care Medicine, Germany
| | - Can M Luedeke
- Department of Anesthesiology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Tina Ramishvili
- Department of Anesthesiology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Giselle D Jaconia
- Department of Anesthesiology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Flora T Scheffenbichler
- Department of Anesthesiology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA; Department of Anesthesiology and Intensive Care Medicine, Ulm University, Ulm, Germany
| | - Terry-Ann Chambers
- Department of Anesthesiology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Ibraheem M Karaye
- Department of Anesthesiology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA; Department of Population Health, Hofstra University, Hempstead, NY, USA
| | - Matthias Eikermann
- Department of Anesthesiology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA; Department of Anesthesiology and Intensive Care Medicine, University of Duisburg-Essen, Essen, Germany.
| | - Jerry Chao
- Department of Anesthesiology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA
| | - William M Jackson
- Department of Anesthesiology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA
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McCann S, Helfer VE, Balevic SJ, Hornik CD, Goldstein SL, Autmizguine J, Meyer M, Al-Uzri A, Anderson SG, Payne EH, Turdalieva S, Gonzalez D. Using Real-World Data to Externally Evaluate Population Pharmacokinetic Models of Dexmedetomidine in Children and Infants. J Clin Pharmacol 2024; 64:963-974. [PMID: 38545761 DOI: 10.1002/jcph.2434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Accepted: 03/04/2024] [Indexed: 07/30/2024]
Abstract
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.
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Affiliation(s)
- Sean McCann
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Victória E Helfer
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Stephen J Balevic
- Department of Pediatrics, Duke University Medical Center, Durham, NC, USA
- Duke Clinical Research Institute, Durham, NC, USA
| | - Chi D Hornik
- Department of Pediatrics, Duke University Medical Center, Durham, NC, USA
- Duke Clinical Research Institute, Durham, NC, USA
| | | | - Julie Autmizguine
- Department of Pediatrics, Center Hospitalier Universitaire Sainte-Justine, Montreal, Quebec, Canada
| | - Marisa Meyer
- Critical Care Medicine, Nemours Children's Hospital, Delaware, Wilmington, DE, USA
| | - Amira Al-Uzri
- Oregon Health and Science University, Portland, OR, USA
| | | | | | | | - Daniel Gonzalez
- Duke Clinical Research Institute, Durham, NC, USA
- Division of Clinical Pharmacology, Department of Medicine, Duke University School of Medicine, Durham, NC, USA
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Bardol M, Pan S, Walker SM, Standing JF, Dawes JM. Pharmacokinetic pharmacodynamic modeling of analgesics and sedatives in children. Paediatr Anaesth 2023; 33:781-792. [PMID: 37341161 PMCID: PMC10947261 DOI: 10.1111/pan.14712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 05/18/2023] [Accepted: 05/21/2023] [Indexed: 06/22/2023]
Abstract
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.
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Affiliation(s)
- Maddlie Bardol
- Infection, Immunity and Inflammation, Great Ormond Street Institute of Child HealthUniversity College LondonLondonUK
| | - Shan Pan
- Infection, Immunity and Inflammation, Great Ormond Street Institute of Child HealthUniversity College LondonLondonUK
| | - Suellen M. Walker
- Department of Anaesthesia and Pain MedicineGreat Ormond St Hospital NHS Foundation TrustLondonUK
- Developmental Neurosciences Program, UCL Great Ormond St Institute of Child HealthUniversity College LondonLondonUK
| | - Joseph F. Standing
- Infection, Immunity and Inflammation, Great Ormond Street Institute of Child HealthUniversity College LondonLondonUK
- Department of PharmacyGreat Ormond St Hospital NHS Foundation TrustLondonUK
| | - Joy M. Dawes
- Infection, Immunity and Inflammation, Great Ormond Street Institute of Child HealthUniversity College LondonLondonUK
- Department of Anaesthesia and Pain MedicineGreat Ormond St Hospital NHS Foundation TrustLondonUK
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4
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Morse JD, Cortinez LI, Anderson BJ. Considerations for Intravenous Anesthesia Dose in Obese Children: Understanding PKPD. J Clin Med 2023; 12:jcm12041642. [PMID: 36836174 PMCID: PMC9960599 DOI: 10.3390/jcm12041642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 02/09/2023] [Accepted: 02/16/2023] [Indexed: 02/22/2023] Open
Abstract
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.
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Affiliation(s)
- James Denzil Morse
- Department of Anaesthesiology, University of Auckland, Park Road, Auckland 1023, New Zealand
| | - Luis Ignacio Cortinez
- División Anestesiología, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
| | - Brian Joseph Anderson
- Department of Anaesthesiology, University of Auckland, Park Road, Auckland 1023, New Zealand
- Department of Anaesthesia, Auckland Children’s Hospital, Park Road, Private Bag 92024, Auckland 1023, New Zealand
- Correspondence: ; Tel.:+64-9-3074903; Fax: +64-9-3078986
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Disma N, Goffredo BM, Cairoli S, Cirillo G, Morse J, Anderson BJ. Justification Of Empiric Methodology to Determine Dexmedetomidine Dose for the TREX Study. Paediatr Anaesth 2022; 33:236-242. [PMID: 36398423 PMCID: PMC10107467 DOI: 10.1111/pan.14605] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 11/08/2022] [Accepted: 11/12/2022] [Indexed: 11/19/2022]
Abstract
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.
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Affiliation(s)
- Nicola Disma
- Unit for Research and Innovation, Department of AnaesthesiaIRCCS Istituto Giannina GasliniGenovaItaly
| | - Bianca M. Goffredo
- Division of Metabolic Disease and Drug BiologyIRCCS Ospedale Bambino GesùRomeItaly
| | - Sara Cairoli
- Division of Metabolic Disease and Drug BiologyIRCCS Ospedale Bambino GesùRomeItaly
| | - Ginevra Cirillo
- Unit for Research and Innovation, Department of AnaesthesiaIRCCS Istituto Giannina GasliniGenovaItaly
| | - James Morse
- Department Anesthesiology, Faculty Medicine and Health ScienceUniversity of AucklandAucklandNew Zealand
| | - Brian J. Anderson
- Department Anesthesiology, Faculty Medicine and Health ScienceUniversity of AucklandAucklandNew Zealand
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Eizaga Rebollar R, García Palacios MV, Fernández Riobó MC, Torres Morera LM. Dexmedetomidine and perioperative analgesia in children. REVISTA ESPANOLA DE ANESTESIOLOGIA Y REANIMACION 2022; 69:487-492. [PMID: 36100555 DOI: 10.1016/j.redare.2022.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 03/25/2021] [Indexed: 06/15/2023]
Abstract
Dexmedetomidine (DEX) is an anaesthetic agent that mimics natural deep sleep and produces minimal cardiorespiratory depression. As such, it is a very valuable option in the management of such a challenging population as paediatric patients. The main objective of this mini review was to evaluate the role of DEX as a perioperative analgesic in children receiving anaesthesia. We searched Google, Pubmed, Embase and the Cochrane Library for articles published between 2010 and 2021, and reviewed various of aspects of DEX, such as pharmacology, effectiveness, safety, and the most recent evidence on its clinical use as an analgesic in paediatric anaesthesia. We also include a cost estimate of perioperative analgesia with DEX.
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Affiliation(s)
- R Eizaga Rebollar
- Servicio de Anestesiología y Reanimación, Hospital Universitario Puerta de Mar, Cádiz, Spain.
| | - M V García Palacios
- Servicio de Medicina Preventiva y Salud Pública, Hospital Universitario Puerta de Mar, Cádiz, Spain
| | - M C Fernández Riobó
- Servicio de Anestesiología y Reanimación, Hospital Universitario Puerta de Mar, Cádiz, Spain
| | - L M Torres Morera
- Servicio de Anestesiología y Reanimación, Hospital Universitario Puerta de Mar, Cádiz, Spain
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7
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Morse JD, Cortinez LI, Anderson BJ. Pharmacokinetic Pharmacodynamic Modelling Contributions to Improve Paediatric Anaesthesia Practice. J Clin Med 2022; 11:jcm11113009. [PMID: 35683399 PMCID: PMC9181587 DOI: 10.3390/jcm11113009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 05/24/2022] [Accepted: 05/25/2022] [Indexed: 12/10/2022] Open
Abstract
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.
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Affiliation(s)
- James D. Morse
- Department of Anaesthesiology, University of Auckland, Park Road, Auckland 1023, New Zealand;
| | - Luis Ignacio Cortinez
- División Anestesiología, Escuela de Medicina, Pontificia Universidad Católica de Chile, San Diego de Chile 8331150, Chile;
| | - Brian J. Anderson
- Department of Anaesthesiology, University of Auckland, Park Road, Auckland 1023, New Zealand;
- Correspondence: ; Tel.: +64-9-3074903; Fax: +64-9-3078986
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James NT, Breeyear JH, Caprioli R, Edwards T, Hachey B, Kannankeril PJ, Keaton JM, Marshall MD, Van Driest SL, Choi L. Population Pharmacokinetic Analysis of Dexmedetomidine in Children using Real World Data from Electronic Health Records and Remnant Specimens. Br J Clin Pharmacol 2021; 88:2885-2898. [PMID: 34957589 DOI: 10.1111/bcp.15194] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 11/18/2021] [Accepted: 12/14/2021] [Indexed: 11/30/2022] Open
Abstract
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.
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Affiliation(s)
- Nathan T James
- Departments of Biostatistics, Vanderbilt University Medical Center, Nashville, TN
| | | | | | - Todd Edwards
- Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Brian Hachey
- Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Prince J Kannankeril
- Pediatrics, Vanderbilt University Medical Center, Nashville, TN.,Center for Pediatric Precision Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Jacob M Keaton
- Medicine, Vanderbilt University Medical Center, Nashville, TN.,Center for Precision Health Research, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD
| | - Matthew D Marshall
- Pharmaceutical Services, Vanderbilt University Medical Center, Nashville, TN
| | - Sara L Van Driest
- Medicine, Vanderbilt University Medical Center, Nashville, TN.,Pediatrics, Vanderbilt University Medical Center, Nashville, TN.,Center for Pediatric Precision Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Leena Choi
- Departments of Biostatistics, Vanderbilt University Medical Center, Nashville, TN
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Ashraf MW, Uusalo P, Scheinin M, Saari TI. Population Modelling of Dexmedetomidine Pharmacokinetics and Haemodynamic Effects After Intravenous and Subcutaneous Administration. Clin Pharmacokinet 2021; 59:1467-1482. [PMID: 32462542 PMCID: PMC7658092 DOI: 10.1007/s40262-020-00900-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Background and Objective Dexmedetomidine is a potent agonist of α2-adrenoceptors causing dose-dependent sedation in humans. Intravenous dexmedetomidine is commonly used perioperatively, but an extravascular route of administration would be favoured in palliative care. Subcutaneous infusions provide desired therapeutic plasma concentrations with fewer unwanted effects as compared with intravenous dosing. We aimed to develop semi-mechanistic population models for predicting pharmacokinetic and pharmacodynamic profiles of dexmedetomidine after intravenous and subcutaneous dosing. Methods Non-linear mixed-effects modelling was performed using previously collected concentration and haemodynamic effects data from ten (eight in the intravenous phase) healthy human subjects, aged 19–27 years, receiving 1 µg/kg of intravenous or subcutaneous dexmedetomidine during a 10-min infusion. Results The absorption of dexmedetomidine from the subcutaneous injection site, and distribution to local subcutaneous fat tissue was modelled using a semi-physiological approach consisting of a depot and fat compartment, while a two-compartment mammillary model explained further disposition. Dexmedetomidine-induced reductions in plasma norepinephrine concentrations were accurately described by an indirect response model. For blood pressure models, the net effect was specified as hyper- and hypotensive effects of dexmedetomidine due to vasoconstriction on peripheral arteries and sympatholysis mediated via the central nervous system, respectively. A heart rate model combined the dexmedetomidine-induced sympatholytic effect, and input from the central nervous system, predicted from arterial blood pressure levels. Internal evaluation confirmed the predictive performance of the final models, as well as the accuracy of the parameter estimates with narrow confidence intervals. Conclusions Our final model precisely describes dexmedetomidine pharmacokinetics and accurately predicts dexmedetomidine-induced sympatholysis and other pharmacodynamic effects. After subcutaneous dosing, dexmedetomidine is taken up into subcutaneous fat tissue, but our simulations indicate that accumulation of dexmedetomidine in this compartment is insignificant. ClinicalTrials.org NCT02724098 and EudraCT 2015-004698-34 Electronic supplementary material The online version of this article (10.1007/s40262-020-00900-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Muhammad W Ashraf
- Department of Anaesthesiology and Intensive Care, University of Turku, Kiinamyllynkatu 4-8 (11A5), P.O. Box 52, 20521, Turku, Finland
| | - Panu Uusalo
- Department of Anaesthesiology and Intensive Care, University of Turku, Kiinamyllynkatu 4-8 (11A5), P.O. Box 52, 20521, Turku, Finland.,Division of Perioperative Services, Intensive Care and Pain Medicine, Turku University Hospital, Turku, Finland
| | - Mika Scheinin
- Institute of Biomedicine, University of Turku, Turku, Finland.,Unit of Clinical Pharmacology, Turku University Hospital, Turku, Finland
| | - Teijo I Saari
- Department of Anaesthesiology and Intensive Care, University of Turku, Kiinamyllynkatu 4-8 (11A5), P.O. Box 52, 20521, Turku, Finland. .,Division of Perioperative Services, Intensive Care and Pain Medicine, Turku University Hospital, Turku, Finland.
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10
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Morse JD, Cortinez LI, Anderson BJ. Pharmacokinetic concepts for dexmedetomidine target-controlled infusion pumps in children. Paediatr Anaesth 2021; 31:924-931. [PMID: 34085357 DOI: 10.1111/pan.14235] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 05/26/2021] [Accepted: 05/31/2021] [Indexed: 12/15/2022]
Abstract
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.
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Affiliation(s)
- James D Morse
- Department of Pharmacology & Clinical Pharmacology, Auckland University, Auckland, New Zealand
| | - Luis Ignacio Cortinez
- División Anestesiología, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago de Chile, Chile
| | - Brian J Anderson
- Department of Anaesthesiology, University of Auckland, Auckland, New Zealand
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Estimation of the Loading Dose for Target-Controlled Infusion of Dexmedetomidine. Reply to Eleveld et al. Comment on "Morse et al. A Universal Pharmacokinetic Model for Dexmedetomidine in Children and Adults. J. Clin. Med. 2020, 9, 3480". J Clin Med 2021; 10:jcm10143004. [PMID: 34300170 PMCID: PMC8306792 DOI: 10.3390/jcm10143004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 05/30/2021] [Indexed: 01/27/2023] Open
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Eizaga Rebollar R, García Palacios MV, Del Carmen Fernández Riobó M, Torres Morera LM. Dexmedetomidine & perioperative analgesia in children. REVISTA ESPANOLA DE ANESTESIOLOGIA Y REANIMACION 2021; 69:S0034-9356(21)00144-4. [PMID: 34049712 DOI: 10.1016/j.redar.2021.03.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 03/24/2021] [Accepted: 03/25/2021] [Indexed: 10/21/2022]
Abstract
Dexmedetomidine (DEX) is an anaesthetic agent that mimics natural deep sleep and produces minimal cardiorespiratory depression. As such, it is a very valuable option in the management of such a challenging population as paediatric patients. The main objective of this mini review was to evaluate the role of DEX as a perioperative analgesic in children receiving anaesthesia. We searched Google, Pubmed, Embase and the Cochrane Library for articles published between 2010 and 2021, and reviewed various of aspects of DEX, such as pharmacology, effectiveness, safety, and the most recent evidence on its clinical use as an analgesic in paediatric anaesthesia. We also include a cost estimate of perioperative analgesia with DEX.
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Affiliation(s)
- R Eizaga Rebollar
- Servicio de Anestesiología y Reanimación, Hospital Universitario Puerta de Mar, Cádiz, España.
| | - M V García Palacios
- Servicio de Medicina Preventiva y Salud Pública, Hospital Universitario Puerta de Mar, Cádiz, España
| | | | - L M Torres Morera
- Servicio de Anestesiología y Reanimación, Hospital Universitario Puerta de Mar, Cádiz, España
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van Hoorn CE, Flint RB, Skowno J, Davies P, Engelhardt T, Lalwani K, Olutoye O, Ista E, de Graaff JC. Off-label use of dexmedetomidine in paediatric anaesthesiology: an international survey of 791 (paediatric) anaesthesiologists. Eur J Clin Pharmacol 2021; 77:625-635. [PMID: 33119787 PMCID: PMC7935836 DOI: 10.1007/s00228-020-03028-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 10/15/2020] [Indexed: 01/02/2023]
Abstract
PURPOSE The purpose of this international study was to investigate prescribing practices of dexmedetomidine by paediatric anaesthesiologists. METHODS We performed an online survey on the prescription rate of dexmedetomidine, route of administration and dosage, adverse drug reactions, education on the drug and overall experience. Members of specialist paediatric anaesthesia societies of Europe (ESPA), New Zealand and Australia (SPANZA), Great Britain and Ireland (APAGBI) and the USA (SPA) were consulted. Responses were collected in July and August 2019. RESULTS Data from 791 responders (17% of 5171 invitees) were included in the analyses. Dexmedetomidine was prescribed by 70% of the respondents (ESPA 53%; SPANZA 69%; APAGBI 34% and SPA 96%), mostly for procedural sedation (68%), premedication (46%) and/or ICU sedation (46%). Seventy-three percent had access to local or national protocols, although lack of education was the main reason cited by 26% of the respondents not to prescribe dexmedetomidine. The main difference in dexmedetomidine use concerned the age of patients (SPA primarily < 1 year, others primarily > 1 year). The dosage varied widely ranging from 0.2-5 μg kg-1 for nasal premedication, 0.2-8 μg kg-1 for nasal procedural sedation and 0-4 μg kg-1 intravenously as adjuvant for anaesthesia. Only ESPA members (61%) had noted an adverse drug reaction, namely bradycardia. CONCLUSION The majority of anaesthesiologists use dexmedetomidine in paediatrics for premedication, procedural sedation, ICU sedation and anaesthesia, despite the off-label use and sparse evidence. The large intercontinental differences in prescribing dexmedetomidine call for consensus and worldwide education on the optimal use in paediatric practice.
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Affiliation(s)
- Camille E van Hoorn
- Department of Anaesthesiology, Erasmus University Medical Centre -Sophia Children's Hospital, Rotterdam, The Netherlands.
- Department of Paediatric Surgery, Erasmus University Medical Centre -Sophia Children's Hospital, PO Box: 2060, 3000 CB, Rotterdam, The Netherlands.
| | - Robert B Flint
- Division of Neonatology, Department of Paediatrics, Erasmus University Medical Centre -Sophia Children's Hospital, Rotterdam, The Netherlands
- Department of Hospital Pharmacy, Erasmus University Medical Centre, Rotterdam, The Netherlands
| | - Justin Skowno
- Department of Anaesthesiology, Children's Hospital at Westmead, University of Sydney, Sydney, Australia
| | - Paul Davies
- Department of Anaesthesia and Pain Management, The Royal Children's Hospital, Melbourne, Australia
| | - Thomas Engelhardt
- Department of Anaesthesia, Royal Children's Hospital Aberdeen and School of Medicine, University of Aberdeen, Aberdeen, UK
- Department of Anaesthesia, McGill University Health Center, Montreal Children's Hospital, Montreal, QC, Canada
| | - Kirk Lalwani
- Department of Anaesthesiology and Paediatrics, Oregon Health and Science University, Portland, OR, USA
| | - Olutoyin Olutoye
- Department of Anaesthesiology, Peri-operative and Pain Medicine, Texas Children's Hospital, Houston, TX, 77030, USA
| | - Erwin Ista
- Department of Internal Medicine - Nursing Science, Erasmus University Medical Centre, Rotterdam, The Netherlands
- Department of Paediatric Surgery, Paediatric Intensive Care, Erasmus University Medical Centre - Sophia Children's Hospital, Rotterdam, The Netherlands
| | - Jurgen C de Graaff
- Department of Anaesthesiology, Erasmus University Medical Centre -Sophia Children's Hospital, Rotterdam, The Netherlands
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A Universal Pharmacokinetic Model for Dexmedetomidine in Children and Adults. J Clin Med 2020; 9:jcm9113480. [PMID: 33126702 PMCID: PMC7692360 DOI: 10.3390/jcm9113480] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Revised: 10/25/2020] [Accepted: 10/26/2020] [Indexed: 02/07/2023] Open
Abstract
A universal pharmacokinetic model was developed from pooled paediatric and adult data (40.6 postmenstrual weeks, 70.8 years, 3.1-152 kg). A three-compartment pharmacokinetic model with first-order elimination was superior to a two-compartment model to describe these pooled dexmedetomidine data. Population parameter estimates (population parameter variability%) were clearance (CL) 0.9 L/min/70 kg (36); intercompartmental clearances (Q2) 1.68 L/min/70 kg (63); Q3 0.62 L/min/70 kg (90); volume of distribution in the central compartment (V1) 25.2 L/70 kg (103.9); rapidly equilibrating peripheral compartment (V2) 34.4 L/70 kg (41.8); slow equilibrating peripheral compartment (V3) 65.4 L/70 kg (62). Obesity was best described by fat-free mass for clearances and normal fat mass for volumes with a factor for fat mass (FfatV) of 0.293. Models describing dexmedetomidine pharmacokinetics in adults can be applied to children by accounting for size (allometry) and age (maturation). This universal dexmedetomidine model is applicable to a broad range of ages and weights: neonates through to obese adults. Lean body weight is a better size descriptor for dexmedetomidine clearance than total body weight. This parameter set could be programmed into target-controlled infusion pumps for use in a broad population.
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Dexmedetomidine: What's New for Pediatrics? A Narrative Review. J Clin Med 2020; 9:jcm9092724. [PMID: 32846947 PMCID: PMC7565844 DOI: 10.3390/jcm9092724] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 07/17/2020] [Accepted: 07/28/2020] [Indexed: 02/07/2023] Open
Abstract
Over the past few years, despite the lack of approved pediatric labelling, dexmedetomidine’s (DEX) use has become more prevalent in pediatric clinical practice as well as in research trials. Its respiratory-sparing effects and bioavailability by various routes are only some of the valued features of DEX. In recent years the potential organ-protective effects of DEX, with the possibility for preserving neurocognitive function, has put it in the forefront of clinical and bench research. This comprehensive review focused on the pediatric literature but presents relevant, supporting adult and animal studies in order to detail the recent growing body of literature around the pharmacology, end-organ effects, organ-protective effects, alternative routes of administration, synergetic effects, and clinical applications, with considerations for the future.
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A Population Pharmacokinetic Model of Intravenous Dexmedetomidine for Mechanically Ventilated Children after Neurosurgery. J Clin Med 2019; 8:jcm8101563. [PMID: 31581476 PMCID: PMC6832515 DOI: 10.3390/jcm8101563] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 09/13/2019] [Accepted: 09/24/2019] [Indexed: 01/24/2023] Open
Abstract
Dexmedetomidine is a selective alpha-2 adrenergic agonist with concurrent sedative and analgesic effects, and it is being increasingly used in pediatric anesthesia and intensive care. This study aimed to investigate the pharmacokinetics of intravenous dexmedetomidine in mechanically ventilated children in the intensive care unit (ICU) after neurosurgery. Pediatric patients aged 2–12 years, who were mechanically ventilated in ICU after neurosurgery, were allocated into a low-dose (n = 15) or high-dose (n = 14) group. The low-dose group received dexmedetomidine at a loading dose of 0.25 µg/kg for 10 min, followed by a maintenance dose of 0.25 µg/kg/h for 50 min, whereas the high-dose group received dexmedetomidine at a loading dose of 0.5 µg/kg for 10 min, followed by a maintenance dose of 0.5 µg/kg/h for 50 min. Serial blood samples were collected for a pharmacokinetic analysis up to 480 min after the end of the infusion. The sedative effect of dexmedetomidine was assessed using the Bispectral Index and University of Michigan Sedation Scale. Adverse reactions, electrocardiography findings, and vital signs were monitored for a safety assessment. A population pharmacokinetic analysis was performed using non-linear mixed effects modeling. Dexmedetomidine induced a moderate-to-deep degree of sedation during infusion in both groups. The pharmacokinetics of dexmedetomidine were best described by a two-compartment disposition model with first-order elimination kinetics. The parameters were standardized for a body weight of 70 kg using an allometric power model. The population estimates (95% confidence interval) per 70 kg body weight were as follows: clearance of 81.0 (72.9–90.9) L/h, central volume of distribution of 64.2 (50.6–81.0) L, intercompartment clearance of 116.4 (90.6–156.0) L/h, and peripheral volume of distribution of 167 (132–217) L. No serious adverse reactions or hemodynamic changes requiring the discontinuation of dexmedetomidine were observed. Dexmedetomidine had increased clearance and volume of distribution in mechanically ventilated children in ICU after neurosurgery, thereby indicating the need to adjust the dosage to obtain a target plasma concentration.
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van Dijkman SC, De Cock PAJG, Smets K, Decaluwe W, Smits A, Allegaert K, Vande Walle J, De Paepe P, Della Pasqua O. Dose rationale and pharmacokinetics of dexmedetomidine in mechanically ventilated new-borns: impact of design optimisation. Eur J Clin Pharmacol 2019; 75:1393-1404. [PMID: 31312867 DOI: 10.1007/s00228-019-02708-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Accepted: 06/11/2019] [Indexed: 12/11/2022]
Abstract
PURPOSE There is a need for alternative analgosedatives such as dexmedetomidine in neonates. Given the ethical and practical difficulties, protocol design for clinical trials in neonates should be carefully considered before implementation. Our objective was to identify a protocol design suitable for subsequent evaluation of the dosing requirements for dexmedetomidine in mechanically ventilated neonates. METHODS A published paediatric pharmacokinetic model was used to derive the dosing regimen for dexmedetomidine in a first-in-neonate study. Optimality criteria were applied to optimise the blood sampling schedule. The impact of sampling schedule optimisation on model parameter estimation was assessed by simulation and re-estimation procedures for different simulation scenarios. The optimised schedule was then implemented in a neonatal pilot study. RESULTS Parameter estimates were more precise and similarly accurate in the optimised scenarios, as compared to empirical sampling (normalised root mean square error: 1673.1% vs. 13,229.4% and relative error: 46.4% vs. 9.1%). Most importantly, protocol deviations from the optimal design still allowed reasonable parameter estimation. Data analysis from the pilot group (n = 6) confirmed the adequacy of the optimised trial protocol. Dexmedetomidine pharmacokinetics in term neonates was scaled using allometry and maturation, but results showed a 20% higher clearance in this population compared to initial estimates obtained by extrapolation from a slightly older paediatric population. Clearance for a typical neonate, with a post-menstrual age (PMA) of 40 weeks and weight 3.4 kg, was 2.92 L/h. Extension of the study with 11 additional subjects showed a further increased clearance in pre-term subjects with lower PMA. CONCLUSIONS The use of optimal design in conjunction with simulation scenarios improved the accuracy and precision of the estimates of the parameters of interest, taking into account protocol deviations, which are often unavoidable in this event-prone population.
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Affiliation(s)
- Sven C van Dijkman
- Division of Pharmacology, Leiden Academic Centre for Drug Research, Leiden, The Netherlands
| | - Pieter A J G De Cock
- Heymans Institute of Pharmacology, Ghent University, Ghent, Belgium
- Department of Pharmacy, Ghent University Hospital, Ghent, Belgium
| | - Koenraad Smets
- Department of Neonatology, Ghent University Hospital, Ghent, Belgium
| | - Wim Decaluwe
- Department of Neonatology, AZ Sint Jan Brugge-Oostende AV, Bruges, Belgium
| | - Anne Smits
- Neonatal Intensive Care Unit, University Hospital Leuven, Leuven, Belgium
| | - Karel Allegaert
- Intensive Care and Department of Pediatric Surgery, Erasmus MC-Sophia Children's Hospital, Rotterdam, The Netherlands
- Department of Development and Regeneration, KU Leuven, Leuven, Belgium
| | - Johan Vande Walle
- Department of Paediatric Nephrology, Ghent University Hospital, Ghent, Belgium
| | - Peter De Paepe
- Heymans Institute of Pharmacology, Ghent University, Ghent, Belgium
| | - Oscar Della Pasqua
- Clinical Pharmacology and Therapeutics, University College London, BMA House, Tavistock Square, London, WC1H 9JP, UK.
- Clinical Pharmacology Modelling & Simulation, GlaxoSmithKline, Uxbridge, UK.
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Pharmacokinetic–pharmacodynamic population modelling in paediatric anaesthesia and its clinical translation. Curr Opin Anaesthesiol 2019; 32:353-362. [DOI: 10.1097/aco.0000000000000725] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Rivera-Espinosa L, Toledo-López A, Chávez-Pacheco JL, Alemón-Medina R, Gómez-Garduño J, Lugo-Goytia G, García-Álvarez R, Juárez-Olguín H, Torres-Espíndola LM, Pérez-Guillé MG. Determination of blood dexmedetomidine in dried blood spots by LC-MS/MS to screen therapeutic levels in paediatric patients. PLoS One 2019; 14:e0210391. [PMID: 30640937 PMCID: PMC6331108 DOI: 10.1371/journal.pone.0210391] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 12/21/2018] [Indexed: 12/04/2022] Open
Abstract
Dexmedetomidine is an imidazole derivative, with high affinity for α2 adrenergic receptors, used for sedation, analgesia and adjuvant anaesthesia. In this study, an analytical method for the quantification of dexmedetomidine in dried blood spots was developed, validated and applied. The drug was extracted from dried blood spot by liquid extraction; the separation was carried out by ultra high-resolution liquid chromatography in reverse phase coupled to tandem mass spectrometry method. An X Select cyano 5 μm HSS column (2.1 X 150 mm, Waters) and a mobile phase composed of 0.1% formic acid: acetonitrile [50:50 v/v], were used. The test was linear over the concentration range of 50 to 2000 pg/mL. The coefficients of variation for the intra and interday trials were less than 15%. The drug was stable under the conditions tested. The method was successfully applied for the quantification of 6 patients, aged 0 to 2 years, with classification ASA I, who underwent ambulatory surgeries, receiving a dose of 1 μg/Kg dexmedetomidine IV. The drug concentrations in the different sampling times were in the range of 76 to 868 pg/mL.
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Affiliation(s)
| | | | | | | | | | - Gustavo Lugo-Goytia
- Anaesthesiology and Critical Medicine Department, National Institute of Medical Sciences and Nutrition, Mexico City, Mexico, Intensive Care Unit, National Institute of Respiratory Diseases, Mexico City, Mexico
| | | | - Hugo Juárez-Olguín
- Pharmacology Laboratory, National Institute of Paediatrics, Mexico City, Mexico
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