Evaluation of a pediatric continuous-infusion vancomycin therapy guideline

Evaluation of Continuous Infusion Vancomycin in a Pediatric Hematology/Oncology Population

BACKGROUND

Continuous infusion vancomycin (CIV) may benefit children who are unable to achieve therapeutic concentrations with intermittent vancomycin dosing and may facilitate outpatient administration by alleviating the burden of frequent dosing intervals. Previous studies have used variable dosing regimens and steady-state concentration goals. The purpose of this study was to evaluate the total daily dose (TDD) of CIV required to achieve therapeutic steady-state concentrations of 15-25 µg/mL in pediatric hematology/oncology patients.

METHODS

A single-center retrospective study was performed for patients treated with CIV from January 2017 to June 2019. The primary outcome was the TDD required to achieve therapeutic steady-state concentrations on CIV. Secondary outcomes included time to reach therapeutic steady-state concentrations, CIV indications and adverse events associated with CIV.

RESULTS

Data were collected for 71 courses of CIV in 60 patients. Median patient age was 4 years (range: 0.4-20 years). The median TDD required to achieve initial therapeutic concentrations was 50.3 mg/kg/d (interquartile range: 38.8-59.2) and was further divided into age-based cohorts. TDD in mg/kg was significantly lower in the older cohort ( P < 0.001), but there was no statistically significant difference between age-based cohorts with TDD in mg/m 2 ( P = 0.97). Median time to achieve first therapeutic concentration was 19.3 hours (range: 8.6-72.3 hours). The most common indication for CIV was ease of outpatient administration (69.0%). Acute kidney injury incidence was minimal (4.2%).

CONCLUSIONS

CIV is associated with rapid attainment of target concentrations in pediatric hematology/oncology patients and is safe and well tolerated.

Dose optimization and target attainment of vancomycin in children

Vancomycin is a glycopeptide antibiotic that has been adopted in clinical practice to treat gram-positive infections for more than 70 years. Despite vancomycin's long history of therapeutic use, optimal dose adjustments and pharmacokinetic/pharmacodynamic (PK/PD) target attainment in children are still under debate. Therapeutic drug monitoring (TDM) has been widely integrated into pediatric clinical practice to maximize efficacy and safety of vancomycin treatment. Area under the curve (AUC)-guided TDM has been recently recommended instead of trough-only TDM to ensure PK/PD target attainment of AUC0-24h/minimal inhibitory concentration (MIC) > 400 to 600 and minimize acute kidney injury risk. Bayesian forecasting in pediatric patients allows estimation of population PK to accurately predict individual vancomycin concentrations over time, and consequently total vancomycin exposure. AUC-guided TDM for vancomycin, preferably with Bayesian forecasting, is therefore suggested for all pediatric age groups and special pediatric populations. In this review we aim to analyze the current literature on the pediatric use of vancomycin and summarize the current knowledge on dosing optimization for target attainment in special patient populations.

When There Is No Trough: Use and Outcomes of Continuous-Infusion Vancomycin at a Free-Standing Children's Hospital

OBJECTIVE

There is minimal published literature regarding the use of continuous-infusion vancomycin (CIV) in children. The objective of this study was to describe the use, dosing requirements, and outcomes of CIV at a free-standing children's hospital.

METHODS

This is a retrospective review of patients who received CIV while admitted to Nationwide Children's Hospital between July 1, 2010, and June 30, 2020. The total daily dose (TDD) of vancomycin required to attain a target serum vancomycin concentration (SVC) was compared between CIV and intermittent-infusion vancomycin (IIV) administration regimens. Safety outcomes and treatment failure were also explored.

RESULTS

Fourteen patients (77% male) with a median age of 7 years (IQR = 1, 10 years) were included. Most patients (71%) were started on CIV in anticipation of outpatient parenteral antimicrobial therapy. The median TDD required to achieve a target SVC was higher with IIV compared with CIV (82.4 mg/kg/day vs 50.5 mg/kg/day; p = 0.02). Despite higher TDD with IIV, median SVC with IIV was similar to SVC with CIV (16.6 mg/L vs 17.6 mg/L; p = 2.00). There were no safety concerns or therapeutic failures identified with CIV.

CONCLUSIONS

Continuous-infusion vancomycin was a well-tolerated and effective alternative to IIV for the patients included in this study. The TDD of vancomycin required to achieve a target SVC was lower in patients receiving CIV compared with those receiving IIV.

Efficacy and Safety of Continuous Infusion of Vancomycin in Children: A Systematic Review

Vancomycin is used to treat a wide variety of infections within the pediatric population. In adults, continuous infusion of vancomycin (CIV) has been evaluated as an alternative to intermittent infusion of vancomycin (IIV) with potential advantages. In children, the use of CIV is increasing; however, data is currently limited. The objective is to provide efficacy and safety evidence for CIV within this population. The review was carried out following PRISMA guidelines. A bibliographic search was performed for studies on PubMed and EMBASE. Clinical trials and observational studies that reported clinical efficacy and/or target attainment of CIV in pediatrics were included. Articles were reviewed to assess their design and target population, characteristics of vancomycin treatment and the main findings in terms of safety and efficacy. A total of 359 articles were identified, of which seven met the inclusion criteria. All of them evaluated the target attainment, six assessed safety but only three assessed clinical efficacy. The best administration method for this antibiotic within the pediatric population is still unknown due to limited evidence. However, studies conducted thus far suggest pharmacokinetic advantages for CIV. Further investigation is required, in particular for studies comparing IIV with CIV for clinical efficacy and toxicity outcomes.

Pharmacokinetics and safety of pegylated recombinant human granulocyte colony-stimulating factor in children with acute leukaemia

AIMS

This open-label, phase I study evaluated the pharmacokinetics and safety of pegylated recombinant human granulocyte colony-stimulating factor (PEG-rhG-CSF) for the treatment of chemotherapy-induced neutropenia in children with acute leukaemia.

METHODS

PEG-rhG-CSF was administered as a single 100 mcg/kg (3 mg maximum dose) subcutaneous injection at the end of each chemotherapy period when neutropenia occurred. Blood samples were obtained from patients treated with PEG-rhG-CSF. PEG-rhG-CSF serum concentrations were determined by an enzyme-linked immunosorbent assay. Population pharmacokinetic (PPK) analysis was implemented using the nonlinear mixed-effects model. Short-term safety was evaluated through adverse events collection (registered at clinicaltrials.gov identifier: 03844360).

RESULTS

A total of 16 acute leukaemia patients (1.8-13.6 years) were included, of whom two (12.5%) had grade 3 neutropenia, six (37.5%) had grade 4 neutropenia, and eight (50.0%) had severe neutropenia. For PPK modelling, 64 PEG-rhG-CSF serum concentrations were obtainable. A one-compartment model with first-order elimination was used for pharmacokinetic data modelling. The current weight was a significant covariate. The median (range) of clearance (CL) and area under the serum concentration-time curve (AUC) were 5.65 (1.49-14.45) mL/h/kg and 16514.75 (6632.45-54423.30) ng·h/mL, respectively. Bone pain, pyrexia, anaphylaxis and nephrotoxicity were not observed. One patient died 13 days after administration, and the objective assessment of causality was that an association with PEG-rhG-CSF was "possible".

CONCLUSIONS

The AUC of PEG-rhG-CSF (100 mcg/kg, 3 mg maximum dose) in paediatric patients with acute leukaemia were similar to those of PEG-rhG-CSF (100 mcg/kg) in children with sarcoma. PEG-rhG-CSF is safe, representing an important therapeutic option for chemotherapy-induced neutropenia in paediatric patients with acute leukaemia.

Optimizing the Use of Antibiotic Agents in the Pediatric Intensive Care Unit: A Narrative Review

Antibiotics are one of the most prescribed drug classes in the pediatric intensive care unit, yet the incidence of inappropriate antibiotic prescribing remains high in critically ill children. Optimizing the use of antibiotics in this population is imperative to guarantee adequate treatment, avoid toxicity and the occurrence of antibiotic resistance, both on a patient level and on a population level. Antibiotic stewardship encompasses all initiatives to promote responsible antibiotic usage and the PICU represents a major target environment for antibiotic stewardship programs. This narrative review provides a summary of the available knowledge on the optimal selection, duration, dosage, and route of administration of antibiotic treatment in critically ill children. Overall, more scientific evidence on how to optimize antibiotic treatment is warranted in this population. We also give our personal expert opinion on research priorities.

Practice survey on the use of vancomycin in pediatrics in the New Aquitaine region and guidelines of learned societies

INTRODUCTION

Vancomycin is an old antibiotic whose use is still being debated today. The objective of this work was to establish an inventory of the use of vancomycin in the various pediatric and neonatal hospital services in the New Aquitaine region.

MATERIALS AND METHODS

A declaratory practice survey was conducted in 49 pediatric and neonatal hospital units. These practices were compared with the guidelines of several learned societies.

RESULTS

A total of 36 responses could be analyzed: 12 units (33%) used vancomycin in discontinuous administration, 18 (50%) had opted for continuous infusion, and six used it in both modalities (17%). The reported dosages were highly variable. Blood tests were performed by 26 units (72%), but the target values of the trough serum concentration were also highly variable. After dosing, all units reported adjusting the dosage and re-dosing after modification (26/26). Finally, 21 units (58%) reported taking into account the MIC of the possibly isolated bacterium.

CONCLUSION

Our study shows that vancomycin is used in very different ways from one unit to another, within the same region, including in ways not recommended by the main learned societies. Much work remains to be done to determine the optimal dosages of vancomycin in pediatrics, to set the serum trough concentration of vancomycin values, and to determine whether continuous infusion use is comparable to discontinuous administration in terms of efficacy.

Continuous Infusion Vancomycin in Pediatric Patients: A Critical Review of the Evidence

OBJECTIVE

To evaluate the use of continuous infusion vancomycin in pediatric patients.

DATA SOURCES AND STUDY SELECTION

PubMed, Cochrane Library, International Pharmaceutical Abstracts, and Google Scholar were searched to identify relevant published articles (1977 to November 2019) using the following search terms: vancomycin, neonates, pediatrics, infusion, continuous, administration, children, nephrotoxicity, pharmacokinetics, and pharmacodynamics. All English-language primary references that evaluated continuous infusion vancomycin in pediatric patients were included in this review.

DATA SYNTHESIS

Vancomycin is typically administered with intermittent infusions, but continuous infusion is an alternative delivery method used to improve achievement of target serum concentrations. Fifteen articles were reviewed that evaluated continuous infusion vancomycin in pediatric patients. Study data were heterogeneous with limited evidence to support improved clinical or microbiologic outcomes as compared with intermittent dosing. Potential benefits and limitations of continuous infusions are discussed.

CONCLUSIONS

Currently available evidence is lacking to support routine implementation of continuous infusion vancomycin in pediatric patients. However, it is a therapeutic option in certain clinical conditions and could be beneficial for individuals with serious Gram-positive infections where rapid achievement of target serum concentrations is critical. Continuous infusions may also benefit individuals who do not achieve target concentrations or who experience significant red man syndrome with traditional dosing, particularly when high daily doses are required. Optimal dosing and ideal target serum concentrations have not been established and may vary for different populations. Future prospective randomized clinical trials should be performed to identify optimal dosing and monitoring regimens and determine comparative safety and efficacy with traditional intermittent dosing in various pediatric populations.

Vancomycin-associated Nephrotoxicity and Risk Factors in Critically Ill Children Without Preexisting Renal Injury

BACKGROUND

A recent systematic review concluded that critically ill pediatric patients have higher odds of vancomycin-related nephrotoxicity [odds ratio (OR): 3.61, 95% CI: 1.21-10.74]. We aimed to assess the incidence and risk factors for vancomycin-associated nephrotoxicity in critically ill children without preexisting renal injury.

METHODS

A cohort of children admitted to a pediatric intensive care unit, from 2011 to 2016 treated with vancomycin without preexisting renal injury. The main diagnosis, therapeutic interventions and medications administered in this period were evaluated. Generalized estimating equation models were used to assess the association between clinical covariates and the dependent variable pediatric risk, injury, failure, loss, end-stage renal disease (pRIFLE).

RESULTS

Hundred ten patients, representing 1177 vancomycin days, were analyzed. Vancomycin-associated nephrotoxicity was seen in 11.8%. In a multivariate model, higher vancomycin doses were not associated with poorer renal function (P = 0.08). Higher serum vancomycin levels were weakly associated with pRIFLE classification (OR: 1.05, 95% CI: 1.02-1.07). Furosemide or amphotericin B in addition to the vancomycin treatment was associated with impaired renal function (OR: 2.56, 95% CI: 1.38-4.8 and OR: 7.7 95% CI: 2.55-23, respectively).

CONCLUSIONS

Vancomycin-associated nephrotoxicity in acute ill children without preexisting renal injury, measured with pRIFLE, is close to 11.8%. Furosemide and amphotericin B in addition to the vancomycin treatment are strong predictors of worse pRIFLE scores. The influence of acute kidney injury status at pediatric intensive care unit admission and the method used for renal function assessment might influence the incidence of vancomycin-associated nephrotoxicity and its associated risk factors.

Use of Body Surface Area for Dosing of Vancomycin

OBJECTIVES

Vancomycin weight-based dosing regimens often fail to achieve therapeutic trough serum concentration in children ≤12 years of age and rigorous studies evaluating efficacy and safety of body surface area (BSA)-based dosing regimens have not been performed. We compared vancomycin trough serum concentrations in pediatric patients receiving a weight- or BSA-based dosing regimen.

METHODS

This was a single-center, retrospective study evaluating pediatric patients, ages 1 to 12 years, who received vancomycin from September 2012 to October 2015. Patients received a minimum of 3 consecutive doses at the same scheduled interval within a dosing regimen prior to a measured vancomycin serum trough concentration. The primary outcome was percentage of initial vancomycin trough concentrations ≥10 mg/L. The secondary outcomes were percentage of supratherapeutic, therapeutic, and subtherapeutic vancomycin serum concentration for all patients, including a subset of overweight and obese patients, and number of nephrotoxic occurrences.

RESULTS

BSA-based dosing regimens resulted in 50% of the initial vancomycin trough concentrations ≥ 10 mg/L compared with 17% for the weight-based dosing regimens (p < 0.0001). No statistically significant differences were noted between the 2 dosing regimens for supratherapeutic, therapeutic, or subtherapeutic trough concentrations for all patients, and for the subset of overweight and obese patients. Nephrotoxic occurrences were noted in 7% of the weight-based dosing regimens compared with none in the BSA-based dosing regimens.

CONCLUSIONS

A BSA-based vancomycin dosing regimen resulted in significantly more initial vancomycin trough concentrations ≥10 mg/L and trended towards higher initial vancomycin trough concentrations without observable nephrotoxicity.

Experience with Continuous Infusion Vancomycin Dosing in a Large Pediatric Hospital

BACKGROUND

There is a paucity of data on dosing of continuous infusion of vancomycin (CIV) in pediatric patients, despite it being an attractive treatment option for limiting escalating doses of intermittent infusion of vancomycin. The purpose of this study was to determine the total daily dose of CIV required to attain therapeutic serum vancomycin concentrations (SVCs) in pediatric patients according to age (≥31 days to <2 years, 2 to <8 years, and 8 to <18 years).

METHODS

We retrospectively evaluated patients who were transitioned from intermittent infusion of vancomycin to CIV between January 2013 and December 2016. Demographic data, vancomycin data (indication, dosing, steady-state SVCs, and time to reach goal SVC), and adverse-effect data (infusion reactions and serum creatinine level) were collected.

RESULTS

Of the 240 patients included, 76 had a goal SVC of 10 to 15 µg/mL and 164 had a goal of 15 to 20 µg/mL. The dose of CIV required to reach an SVC of 10 to 15 µg/mL in the youngest age group was 48.4 mg/kg per day versus 45.6 and 39.4 mg/kg per day in the older age groups (P < .005). The 2 younger age groups of patients with a goal SVC of 15 to 20 µg/mL required 50.2 and 50.6 mg/kg per day, respectively, whereas patients aged ≥8 years required 44.7 mg/kg per day (P = .008). One patient experienced renal injury, and 1 experienced renal failure.

CONCLUSIONS

CIV is an effective method for attaining a therapeutic SVC in pediatric patients. Patients <8 years of age require higher dosing than older pediatric patients to reach the goal SVCs of 10 to 15 and 15 to 20 µg/mL.

Continuous vancomycin in a pediatric cystic fibrosis patient

Continuous vancomycin has been previously reported to maximize antimicrobial activity while avoiding toxicities associated with dose escalation, but the efficacy of this dosing strategy has not been reported. This case report describes the successful use of continuous vancomycin, including improvement in lung function and avoidance of nephrotoxicity, demonstrated in a pediatric cystic fibrosis (CF) patient with MRSA.

Implementing an Antibiotic Stewardship Program: Guidelines by the Infectious Diseases Society of America and the Society for Healthcare Epidemiology of America

Evidence-based guidelines for implementation and measurement of antibiotic stewardship interventions in inpatient populations including long-term care were prepared by a multidisciplinary expert panel of the Infectious Diseases Society of America and the Society for Healthcare Epidemiology of America. The panel included clinicians and investigators representing internal medicine, emergency medicine, microbiology, critical care, surgery, epidemiology, pharmacy, and adult and pediatric infectious diseases specialties. These recommendations address the best approaches for antibiotic stewardship programs to influence the optimal use of antibiotics.

Continuous Infusion Vancomycin Through the Addition of Vancomycin to the Continuous Renal Replacement Therapy Solution in the PICU: A Case Series

OBJECTIVES

To describe our experience with achieving therapeutic serum vancomycin concentrations in pediatric continuous renal replacement therapy by using continuous infusion vancomycin by mixing vancomycin into the continuous renal replacement therapy solution.

DESIGN

Retrospective chart review.

SETTING

A 189-bed, freestanding children's tertiary care teaching hospital in Philadelphia, PA.

PATIENTS

Pediatric patients receiving continuous renal replacement therapy from April 1, 2009, through December 31, 2014.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

There were a total of 21 patients who received continuous renal replacement therapy during the study period. Of these, 11 (52.3%) received vancomycin in the continuous renal replacement therapy solution. The median (range) concentration of vancomycin added to the continuous renal replacement therapy solution was 25 mg/L (18-35 mg/L). The mean vancomycin plateau level was 22.8 ± 3.3 mg/L. All patients achieved a serum vancomycin plateau level that was greater than 15 mg/L. There were no adverse events related to the addition of vancomycin to the continuous renal replacement therapy solution.

CONCLUSIONS

The addition of vancomycin to the continuous renal replacement therapy solution(s) is an effective modality that is used for delivering vancomycin continuous infusion and for ensuring therapeutic vancomycin serum plateau levels in the setting of pediatric continuous renal replacement therapy. Further studies are required to evaluate whether this delivery method can lead to improved patient outcomes.

Towards Rational Dosing Algorithms for Vancomycin in Neonates and Infants Based on Population Pharmacokinetic Modeling

Because of the recent awareness that vancomycin doses should aim to meet a target area under the concentration-time curve (AUC) instead of trough concentrations, more aggressive dosing regimens are warranted also in the pediatric population. In this study, both neonatal and pediatric pharmacokinetic models for vancomycin were externally evaluated and subsequently used to derive model-based dosing algorithms for neonates, infants, and children. For the external validation, predictions from previously published pharmacokinetic models were compared to new data. Simulations were performed in order to evaluate current dosing regimens and to propose a model-based dosing algorithm. The AUC/MIC over 24 h (AUC24/MIC) was evaluated for all investigated dosing schedules (target of >400), without any concentration exceeding 40 mg/liter. Both the neonatal and pediatric models of vancomycin performed well in the external data sets, resulting in concentrations that were predicted correctly and without bias. For neonates, a dosing algorithm based on body weight at birth and postnatal age is proposed, with daily doses divided over three to four doses. For infants aged <1 year, doses between 32 and 60 mg/kg/day over four doses are proposed, while above 1 year of age, 60 mg/kg/day seems appropriate. As the time to reach steady-state concentrations varies from 155 h in preterm infants to 36 h in children aged >1 year, an initial loading dose is proposed. Based on the externally validated neonatal and pediatric vancomycin models, novel dosing algorithms are proposed for neonates and children aged <1 year. For children aged 1 year and older, the currently advised maintenance dose of 60 mg/kg/day seems appropriate.