scholarly journals Nebulization of Vancomycin Provides Higher Lung Tissue Concentrations than Intravenous Administration in Ventilated Female Piglets with Healthy Lungs

2020 ◽  
Vol 132 (6) ◽  
pp. 1516-1527 ◽  
Author(s):  
Cristiane Luchesi de Mello Morais ◽  
Jorge Willian Leandro Nascimento ◽  
Aline Corrêa Ribeiro ◽  
Luis Ignacio Cortinez ◽  
Maria José Carvalho Carmona ◽  
...  
Keyword(s):  
Lung Tissue ◽  
High Performance ◽  
Intravenous Route ◽  
Tissue Concentrations ◽  
Mixed Effect ◽  
Mechanically Ventilated ◽  
Routes Of Administration ◽  
Nonlinear Mixed Effect ◽  
Nonlinear Mixed Effect Modeling ◽  
Serum Vancomycin

Abstract Background Intravenous vancomycin is used to treat ventilator-associated pneumonia caused by methicillin-resistant Staphylococcus aureus, but achieves high rates of failure. Vancomycin nebulization may be efficient to provide high vancomycin lung tissue concentrations. The aim of this study was to compare lung tissue and serum concentrations of vancomycin administered intravenously and by aerosol in mechanically ventilated and anesthetized healthy piglets. Methods Twelve female piglets received a single intravenous dose of vancomycin (15 mg/kg) and were killed 1 (n = 6) or 12 h (n = 6) after the end of administration. Twelve piglets received a single nebulized dose of vancomycin (37.5 mg/kg) and were killed 1 (n = 6) or 12 h (n = 6) after the end of the aerosol administration. In each group, vancomycin lung tissue concentrations were assessed on postmortem lung specimens using high-performance liquid chromatography. Blood samples were collected for serum vancomycin concentration measurement 30 min and 1, 2, 4, 6, 8, and 12 h after the end of vancomycin administration. Pharmacokinetics was analyzed by nonlinear mixed effect modeling. Results One hour after vancomycin administration, lung tissue concentrations in the aerosol group were 13 times the concentrations in the intravenous group (median and interquartile range: 161 [71, 301] μg/g versus 12 [4, 42] μg/g; P < 0.0001). Twelve hours after vancomycin administration, lung tissue concentrations in the aerosol group were 63 (23, 119) μg/g and 0 (0, 19) μg/g in the intravenous group (P < 0.0001). A two-compartment weight-scaled allometric model with first-order absorption and elimination best fit serum pharmacokinetics after both routes of administration. Area under the time-concentration curve from 0 to 12 h was lower in the aerosol group in comparison to the intravenous group (56 [8, 70] mg · h · l−1vs. 121 [103, 149] mg · h · l−1, P = 0.002). Using a population model, vancomycin bioavailability was 13% (95% CI, 6 to 69; coefficient of variation = 85%) and absorption rate was slow (absorption half life = 0.3 h). Conclusions Administration of vancomycin by nebulization resulted in higher lung tissue concentrations than the intravenous route. Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New

scholarly journals Pharmacokinetics of Efavirenz at a High Dose of 25 Milligrams per Kilogram per Day in Children 2 to 3 Years Old

2017 ◽  
Vol 61 (7) ◽  
Author(s):  
Claire Pressiat ◽  
Madeleine Amorissani-Folquet ◽  
Caroline Yonaba ◽  
Jean-Marc Treluyer ◽  
Désiré Lucien Dahourou ◽  
...  
Keyword(s):  
Antiretroviral Treatment ◽  
Recommended Dose ◽  
Pharmacokinetic Parameters ◽  
High Dose ◽  
Age Group ◽  
Mixed Effect ◽  
Sleeping Disorders ◽  
Nonlinear Mixed Effect ◽  
Nonlinear Mixed Effect Modeling ◽  
Mixed Effect Modeling

ABSTRACT The MONOD ANRS 12206 trial was designated to assess simplification of a successful lopinavir (LPV)-based antiretroviral treatment in HIV-infected children younger than 3 years of age using efavirenz (EFV; 25 mg/kg of body weight/day) to preserve the class of protease inhibitors for children in that age group. In this substudy, EFV concentrations were measured to check the consistency of an EFV dose of 25 mg/kg and to compare it with the 2016 FDA recommended dose. Fifty-two children underwent blood sampling for pharmacokinetic study at 6 months and 12 months after switching to EFV. We applied a Bayesian approach to derive EFV pharmacokinetic parameters using the nonlinear mixed-effect modeling (NONMEM) program. The proportion of midinterval concentrations 12 h after drug intake (C 12 h) corresponding to the EFV therapeutic pharmacokinetic thresholds (1 to 4 mg/liter) was assessed according to different dose regimens (25 mg/kg in the MONOD study versus the 2016 FDA recommended dose). With both the 25 mg/kg/day dose and the 2016 FDA recommended EFV dose, simulations showed that the majority of C 12 h values were within the therapeutic range (62.6% versus 62.8%). However, there were more children underexposed with the 2016 FDA recommended dose (11.6% versus 1.2%). Conversely, there were more concentrations above the threshold of toxicity with the 25 mg/kg dose (36.2% versus 25.6%), with C 12 h values of up to 15 mg/liter. Only 1 of 52 children was switched back to LPV because of persistent sleeping disorders, but his C 12 h value was within therapeutic ranges. A high EFV dose of 25 mg/kg per day in children under 3 years old achieved satisfactory therapeutic effective levels. However, the 2016 FDA recommended EFV dose appeared to provide more acceptable safe therapeutic profiles. (This study has been registered at ClinicalTrials.gov under identifier NCT01127204.)

Spectral Entropy as an Electroencephalographic Measure of Anesthetic Drug Effect

2004 ◽  
Vol 101 (1) ◽  
pp. 34-42 ◽  
Author(s):  
Ann L.G. Vanluchene ◽  
Hugo Vereecke ◽  
Olivier Thas ◽  
Eric P. Mortier ◽  
Steven L. Shafer ◽  
...  
Keyword(s):  
Drug Effect ◽  
Rank Correlation ◽  
Burst Suppression ◽  
Spectral Entropy ◽  
Anesthetic Drug ◽  
Mixed Effect ◽  
Nonlinear Mixed Effect ◽  
Prediction Probability ◽  
Nonlinear Mixed Effect Modeling ◽  
Mixed Effect Modeling

Background The authors compared the behavior of two calculations of electroencephalographic spectral entropy, state entropy (SE) and response entropy (RE), with the A-Line ARX Index (AAI) and the Bispectral Index (BIS) and as measures of anesthetic drug effect. They compared the measures for baseline variability, burst suppression, and prediction probability. They also developed pharmacodynamic models relating SE, RE, AAI, and BIS to the calculated propofol effect-site concentration (Ceprop). Methods With institutional review board approval, the authors studied 10 patients. All patients received 50 mg/min propofol until either burst suppression greater than 80% or mean arterial pressure less than 50 mmHg was observed. SE, RE, AAI, and BIS were continuously recorded. Ceprop was calculated from the propofol infusion profile. Baseline variability, prediction of burst suppression, prediction probability, and Spearman rank correlation were calculated for SE, RE, AAI, and BIS. The relations between Ceprop and the electroencephalographic measures of drug effect were estimated using nonlinear mixed effect modeling. Results Baseline variability was lowest when using SE and RE. Burst suppression was most accurately detected by spectral entropy. Prediction probability and individualized Spearman rank correlation were highest for BIS and lowest for SE. Nonlinear mixed effect modeling generated reasonable models relating all four measures to Ceprop. Conclusions Compared with BIS and AAI, both SE and RE seem to be useful electroencephalographic measures of anesthetic drug effect, with low baseline variability and accurate burst suppression prediction. The ability of the measures to predict Ceprop was best for BIS.

scholarly journals Fluconazole Population Pharmacokinetics and Dosing for Prevention and Treatment of Invasive Candidiasis in Children Supported with Extracorporeal Membrane Oxygenation

2015 ◽  
Vol 59 (7) ◽  
pp. 3935-3943 ◽  
Author(s):  
Kevin M. Watt ◽  
Daniel Gonzalez ◽  
Daniel K. Benjamin ◽  
Kim L. R. Brouwer ◽  
Kelly C. Wade ◽  
...  
Keyword(s):  
Extracorporeal Membrane Oxygenation ◽  
Compartment Model ◽  
Volume Of Distribution ◽  
Mixed Effect ◽  
Final Model ◽  
Content Type ◽  
Membrane Oxygenation ◽  
Nonlinear Mixed Effect ◽  
Nonlinear Mixed Effect Modeling ◽  
Drug Pharmacokinetics

ABSTRACTCandidainfections are a leading cause of infectious disease-related death in children supported by extracorporeal membrane oxygenation (ECMO). The ECMO circuit can alter drug pharmacokinetics (PK); thus, standard fluconazole dosing may result in suboptimal drug exposures. The objective of our study was to determine the PK of fluconazole in children on ECMO. Forty children with 367 PK samples were included in the analysis. The PK data were analyzed using nonlinear mixed-effect modeling (NONMEM). A one-compartment model best described the data. Weight was included in the base model for clearance (CL) and volume of distribution (V). The final model included the effect of serum creatinine (SCR) level on CL and the effect of ECMO onVas follows: CL (in liters per hour) = 0.019 × weight × (SCR/0.4)−0.29× exp(ηCL) andV(in liters) = 0.93 × weight × 1.4ECMO× exp(ηV). The fluconazoleVwas increased in children supported by ECMO. Consequently, children on ECMO require a higher fluconazole loading dose for prophylaxis (12 mg/kg of body weight) and treatment (35 mg/kg) paired with standard maintenance doses to achieve exposures similar to those of children not on ECMO.

Tetrahydrobiopterin (BH4) responsiveness in neonates with hyperphenylalaninemia: A semi-mechanistically-based, nonlinear mixed-effect modeling

2015 ◽  
Vol 114 (4) ◽  
pp. 564-569 ◽  
Author(s):  
Friedrich Trefz ◽  
Olaf Lichtenberger ◽  
Nenad Blau ◽  
Ania C. Muntau ◽  
Francois Feillet ◽  
...  
Keyword(s):  
Mixed Effect ◽  
Nonlinear Mixed Effect ◽  
Nonlinear Mixed Effect Modeling ◽  
Mixed Effect Modeling

scholarly journals Population Pharmacokinetic/Pharmacogenetic Model for Optimization of Efavirenz Therapy in Caucasian HIV-Infected Patients

2011 ◽  
Vol 55 (11) ◽  
pp. 5314-5324 ◽  
Author(s):  
Almudena Sánchez ◽  
Salvador Cabrera ◽  
Dolores Santos ◽  
M. Paz Valverde ◽  
Aurelio Fuertes ◽  
...  
Keyword(s):  
High Performance ◽  
Plasma Concentrations ◽  
Compartment Model ◽  
Population Pharmacokinetic ◽  
Nucleotide Polymorphisms ◽  
Mixed Effect ◽  
Factors Affecting ◽  
Nonlinear Mixed Effect ◽  
Study Population ◽  
Major Factors

ABSTRACTDespite extensive clinical experience with efavirenz (EFV), unpredictable interindividual variabilities in efficacy and toxicity remain important limitations associated with the use of this antiretroviral. The purpose of this study was to determine the factors affecting EFV pharmacokinetics and to develop a pharmacokinetic/pharmacogenetic (PK/PG) model in a Caucasian population of HIV-infected patients. In total, 869 EFV plasma concentrations from 128 HIV-infected patients treated with EFV were quantitatively assessed using a validated high-performance liquid chromatography technique. All patients were genotyped for 90 single nucleotide polymorphisms (SNPs) in genes coding for proteins involved in the metabolism and transport of EFV, using a MassArray platform provided by Sequenom. The influence of these polymorphisms on EFV pharmacokinetics and the effects of demographic, clinical, biochemical, lifestyle, and concurrent drug covariates were evaluated. Plasma concentrations were fitted by a one-compartment model, with first-order absorption and elimination using nonlinear mixed-effect modeling (NONMEM program). The CYP2B6*6 allele, multidrug resistance-associated protein 4 (MRP4) 1497C→T, and gamma-glutamyltranspeptidase (GGT) were identified as major factors influencing the apparent EFV oral clearance (CL/F), reducing the initial interindividual variability by 54.8%, according to the model CL/F = (12.2 − 0.00279·GGT)·0.602CYP2B6*6 [G/T]·0.354CYP2B6*6 [T/T]·0.793MRP4 1497C→T, where CYP2B6*6 [G/T], CYP2B6*6 [T/T], and MRP4 1497C→T take values of 0 or 1 to indicate the absence or presence of polymorphisms. The detailed genetic analysis conducted in this study identified two of 90 SNPs that significantly impacted CL/F, which might indicate that the remaining SNPs analyzed do not influence this PK parameter, at least in Caucasian populations with characteristics similar to those of our study population.

scholarly journals Multi-experiment nonlinear mixed effect modeling of single-cell translation kinetics after transfection

2018 ◽  
Vol 4 (1) ◽  
Author(s):  
Fabian Fröhlich ◽  
Anita Reiser ◽  
Laura Fink ◽  
Daniel Woschée ◽  
Thomas Ligon ◽  
...  
Keyword(s):  
Single Cell ◽  
Mixed Effect ◽  
Nonlinear Mixed Effect ◽  
Nonlinear Mixed Effect Modeling ◽  
Mixed Effect Modeling

scholarly journals Performance of the SAEM and FOCEI Algorithms in the Open‐Source, Nonlinear Mixed Effect Modeling Tool nlmixr

2019 ◽  
Vol 8 (12) ◽  
pp. 923-930 ◽  
Author(s):  
Rik Schoemaker ◽  
Matthew Fidler ◽  
Christian Laveille ◽  
Justin J. Wilkins ◽  
Richard Hooijmaijers ◽  
...  
Keyword(s):  
Open Source ◽  
Mixed Effect ◽  
Modeling Tool ◽  
Nonlinear Mixed Effect ◽  
Nonlinear Mixed Effect Modeling ◽  
Mixed Effect Modeling
Sign in / Sign up

Export Citation Format

Share Document