Gabapentin as a novel adjunct for postoperative irritability after superior cavopulmonary connection operation in children.

OBJECTIVES: Describing our institution's off-label use of gabapentin to treat irritability after superior cavopulmonary connection surgery and its impact on subsequent opiate and benzodiazepine requirements. METHODS: This is a single-center retrospective cohort study including infants who underwent superior cavopulmonary connection operation between 2011 and 2019. RESULTS: Gabapentin was administered in 74 subjects (74/323, 22.9%) during the observation period, with a median (IQR) starting dose of 5.7 (3.3, 15.0) mg/kg/day and a maximum dose of 10.7 (5.5, 23.4) mg/kg/day. Infants who underwent surgery in 2015-19 were more likely to receive gabapentin compared with those who underwent surgery in 2011-14 (p < 0.0001). Infants prescribed gabapentin were younger at surgery (137 versus 146 days, p = 0.007) and had longer chest tube durations (1.8 versus 0.9 days, p < 0.001), as well as longer postoperative intensive care (5.8 versus 3.1 days, p < 0.0001) and hospital (11.5 versus 7.0 days, p < 0.0001) lengths of stays. The year of surgery was the only predisposing factor associated with gabapentin administration in multivariate analysis. In adjusted linear regression, infants prescribed gabapentin on postoperative day 0-4 (n = 64) had reduced benzodiazepine exposure in the following 3 days (-0.29 mg/kg, 95% CI -0.52 - -0.06, p = 0.01) compared with those not prescribed gabapentin, while no difference was seen in opioid exposure (p = 0.59). CONCLUSIONS: Gabapentin was used with increasing frequency during the study period. There was a modest reduction in benzodiazepine requirements associated with gabapentin administration and no reduction in opioid requirements. A randomised controlled trial could better assess gabapentin's benefits postoperatively in children with congenital heart disease.

Two months outcomes following delirium in the pediatric intensive care unit.

The lasting consequences of delirium in children are not well characterized. This study aimed to compare the two-month outcomes in pediatric intensive care unit (PICU) survivors according to the presence of delirium. Post-hoc analysis of a single-center prospective study of mechanically ventilated (invasive ventilation or non-invasive ventilation) children followed at the CHU Sainte-Justine PICU follow-up clinic two months after PICU discharge, between October 2018 and August 2022. Delirium was defined as one or more Cornell Assessment of Pediatric Delirium (CAPD) scores ≥ 9. Primary outcome was survivors' quality of life and secondary outcomes were sleep and posttraumatic stress and anxiety and depression in parents. Multivariable linear and logistic regression models assessed the independent associations between delirium and outcomes while adjusting for age, sex, comorbidity, diagnosis, severity of illness, PICU length of stay, and invasive mechanical ventilation. Of the 179 children included over a 47 month-period, 117 (65.4%) had delirium. Children with delirium were more commonly intubated (91.5% vs. 30.7%, p < 0.001) and had higher PELOD-2 scores (10 vs. 4, p < 0.001). On multivariable analysis, delirium was associated with a decreased quality of life at 2.3 months post discharge (p = 0.03). The severity of the delirium episode (higher scores of CAPD) was associated with a higher likelihood of sleep disturbances (OR 1.13, p = 0.01) and parental anxiety (OR 1.16, p = 0.01), in addition to lower quality of life (p = 0.03).Conclusions: Two months following their PICU stay, children with delirium had a lower quality of life, suggesting a lasting effect of delirium on children and their families.

Iron Deficiency in Anemic Children Surviving Critical Illness: Post Hoc Analysis of a Single-Center Prospective Cohort in Canada, 2019-2022.

OBJECTIVES: Many children leave the PICU with anemia. The mechanisms of post-PICU anemia are poorly investigated, and treatment of anemia, other than blood, is rarely started during PICU. We aimed to characterize the contributions of iron depletion (ID) and/or inflammation in the development of post-PICU anemia and to explore the utility of hepcidin (a novel iron marker) at detecting ID during inflammation. DESIGN: Post hoc analysis of a single-center prospective study (November 2019 to September 2022). SETTING: PICU, quaternary center, Canada. PATIENTS: Children admitted to PICU with greater than or equal to 48 hours of invasive or greater than or equal to 96 hours of noninvasive ventilation. We excluded patients with preexisting conditions causing anemia or those admitted after cardiac surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Hematological and iron profiles were performed at PICU discharge on 56 participants of which 37 (37/56) were diagnosed with anemia. Thirty-three children (33/56; 59%) were younger than 2 years. Median Pediatric Logistic Organ Dysfunction score was 11 (interquartile range, 6-16). Twenty-four of the 37 anemic patients had repeat bloodwork 2 months post-PICU. Of those, four (4/24; 16%) remained anemic. Hematologic profiles were categorized as: anemia of inflammation (AI), iron deficiency anemia (IDA), IDA with inflammation, and ID (low iron stores without anemia). Seven (7/47; 15%) had AI at discharge, and one had persistent AI post-PICU. Three patients (3/47; 6%) had IDA at discharge; of which one was lost to follow-up and the other two were no longer anemic but had ID post-PICU. Eleven additional patients developed ID post-PICU. In the exploratory analysis, we identified a diagnostic cutoff value for ID during inflammation from the receiver operating characteristic curve for hepcidin of 31.9 pg/mL. This cutoff would increase the detection of ID at discharge from 6% to 34%. CONCLUSIONS: The burden of ID in children post-PICU is high and better management strategies are required. Hepcidin may increase the diagnostic yield of ID in patients with inflammation.

Outcomes of patients supported by mechanical ventilation and their families two months after discharge from pediatric intensive care unit.

Introduction: The outcomes of children undergoing mechanical ventilation (MV) in a Pediatric Intensive Care Unit (PICU) remain poorly characterized and increasing knowledge in this area may lead to strategies that improve care. In this study, we reported the outcomes of children receiving invasive mechanical ventilation (IMV) and/or non-invasive ventilation (NIV), 2 months after PICU discharge. Methods: This is a post-hoc analysis of a single-center prospective study of PICU children followed at the PICU follow-up clinic at CHU Sainte-Justine. Eligible children were admitted to the PICU with ≥2 days of IMV or ≥4 days of NIV. Two months after PICU discharge, patients and families were evaluated by physicians and filled out questionnaires assessing Quality of life (Pediatric Quality of Life Inventory™), development milestones (Ages and Stages Questionnaire), and parental anxiety and depression (Hospital Anxiety and Depression Scale). Results: One hundred and fifty patients were included from October 2018 to December 2021; 106 patients received IMV (±NIV), and 44 patients received NIV exclusively. Admission diagnoses differed between groups, with 30.2% of patients in the IMV group admitted for a respiratory illness vs. 79.5% in the NIV group. For the entire cohort, QoL scores were 78.1% for the physical domain and 80.1% for the psychological domain, and were similar between groups. Children with a respiratory illness exhibited similar symptoms at follow-up whether they were supported by IMV vs. NIV. For developmental outcomes, only 22.2% of pre-school children had normal scores in all ASQ domains. In the entire cohort, symptoms of anxiety were reported in 29.9% and depression in 24.6 of patients. Conclusions: PICU survivors undergoing mechanical ventilation, and their families, experienced significant morbidities 2 months after their critical illness, whether they received IMV or NIV. Children with respiratory illness exhibited a higher prevalence of persistent respiratory difficulties post PICU, whether they underwent IMV or NIV. Patients' quality of life and parental symptoms of anxiety and depression did not differ according to the type of respiratory support. These findings justify the inclusion of patients receiving NIV in the PICU in follow-up assessments as well as those receiving IMV.

Determining Optimal Mean Arterial Blood Pressure Based on Cerebral Autoregulation in Children after Cardiac Surgery.

To evaluate the feasibility of continuous determination of the optimal mean arterial blood pressure (opt-MAP) according to cerebral autoregulation and to describe the opt-MAP, the autoregulation limits, and the time spent outside these limits in children within 48 h of cardiac surgery. Cerebral autoregulation was assessed using the correlation coefficient (COx) between cerebral oxygenation and MAP in children following cardiac surgery. Plots depicting the COx according to the MAP were used to determine the opt-MAP using weighted multiple time windows. For each patient, we estimated (1) the time spent with MAP outside the autoregulation limits and (2) the burden of deviation, defined as the area between the MAP curve and the autoregulation limits when the MAP was outside these limits. Fifty-one patients with a median age of 7.1 (IQR 0.7-52.0) months old were included. The opt-MAP was calculated for 94% (IQR 90-96) of the monitored time. The opt-MAP was significantly lower in neonates < 1 month old. The patients spent 24% (18-31) of the time outside of the autoregulation limits, with no significant differences between age groups. Continuous determination of the opt-MAP is feasible in children within the first 48 h following cardiac surgery.

Morphine versus hydromorphone in pediatrics: a narrative review of latest indications and optimal use in neonates and children.

The management of pain in pediatrics is multimodal and includes non-pharmacologic and pharmacologic approaches. Opioids, and particularly morphine and hydromorphone, are frequently used to treat moderate-to-severe pain. The goals of this review are to describe the pharmacological characteristics of both drugs, to cover the latest evidence of their respective indications, and to promote their safe use in pediatrics. Morphine is the most studied opioid in children and is known to be safe and effective. Morphine and hydromorphone can be used to manage acute pain and are usually avoided when treating chronic non-cancer pain. Current evidence suggests that both opioids have a similar efficacy and adverse effect profile. Hydromorphone has not been studied in neonates but in some centers, it has been used instead of morphine for certain patients. In palliative care, the use of opioids is often indicated and their benefits extend beyond analgesia; indications include treatment of central neuropathic pain in children with severe neurologic impairment and treatment of respiratory distress in the imminently dying patients. The longstanding belief that the use of well-titrated opioids hastens death should be abandoned as robust evidence has shown the opposite. With the current opioid crisis, a responsible use of opioids should be promoted, including limiting the opioid prescription to the patient's anticipated needs, optimizing a multimodal analgesic plan including the use of non-pharmacological measures and non-opioid medications, and providing information on safe storage and disposal to patients and families. More data is needed to better guide the use of morphine and hydromorphone in children.

The Three W's of Acetaminophen In Children: Who, Why, and Which Administration Mode.

Acetaminophen is one of the oldest medications commonly administered in children. Its efficacy in treating fever and pain is well accepted among clinicians. However, the available evidence supporting the use of acetaminophen's different modes of administration remains relatively scarce and poorly known. This short report summarizes the available evidence and provides a framework to guide clinicians regarding a rational use of acetaminophen in children.

Dose Escalation Pharmacokinetic Study of Intranasal Atomized Dexmedetomidine in Pediatric Patients With Congenital Heart Disease.

BACKGROUND: Atomized intranasal dexmedetomidine is an attractive option when sedation is required for pediatric patients as either premedication or the sole agent for noninvasive, nonpainful procedures. While intranasal dexmedetomidine is used frequently in this population, it is still unclear what dose and time of administration relative to the procedure will result in the optimal effect. Knowledge regarding the maximum concentration (C max ) and time to reach maximum concentration (T max ) of intranasally administered dexmedetomidine is the first step toward this. The risk of hemodynamic instability caused by increasing doses of dexmedetomidine necessitates a greater understanding of the pharmacokinetics in children. METHODS: Sixteen pediatric patients 2 to 6 years of age undergoing elective cardiac catheterization received 2 or 4 µg/kg dexmedetomidine intranasally. Plasma concentrations were determined by liquid chromatography-tandem mass spectrometry with a validated assay. Descriptive noncompartmental analysis provided estimates of peak concentrations and time to reach peak concentrations. A population pharmacokinetic model was developed using nonlinear mixed-effects modeling. Simulations were performed using the final model to assess dose concentrations with an alternative dosing regimen of 3 µg/kg. RESULTS: A median peak plasma concentration of 413 pg/mL was achieved 91 minutes after 2 µg/kg dosing, and a median peak plasma concentration of 1000 pg/mL was achieved 54 minutes after 4 µg/kg dosing. A 1-compartment pharmacokinetic model adequately described the data. Three subjects in the 4 µg/kg dosing cohort achieved a dose-limiting toxicity (DLT), defined as a plasma dexmedetomidine concentration >1000 pg/mL. None of these subjects had any significant hemodynamic consequences. Simulations showed that no subjects would experience a level >1000 pg/mL when using a dose of 3 µg/kg. CONCLUSIONS: Concentrations associated with adequate sedation can be achieved with intranasal dexmedetomidine doses of 2 to 4 µg/kg in children 2 to 6 years of age. However, 50% of our evaluable subjects in this cohort reached a plasma concentration >1000 pg/mL. Doses of 3 µg/kg may be optimal in this population, with simulated concentrations remaining below this previously established toxicity threshold. Further studies correlating concentrations with efficacy and adverse effects are needed.

Successful decompressive laparotomy in a neonate with abdominal compartment syndrome on extracorporeal membrane oxygenation following congenital diaphragmatic hernia repair.

Abdominal compartment syndrome (ACS) is a rare complication of extracorporeal membrane oxygenation (ECMO) and is associated with high morbidity and mortality. Despite being the treatment of choice for ACS, decompressive laparotomy (DL) has been a matter of debate in children supported with ECMO due to high bleeding risk and presumed futility. We report the first neonatal DL for ACS while on ECMO following congenital diaphragmatic hernia (CDH) repair. Given its excellent outcomes, our case challenges current literature and supports prompt bedside laparotomy to treat ACS on neonatal ECMO.

Dexmedetomidine in Children on Extracorporeal Membrane Oxygenation: Pharmacokinetic Data Exploration Using Previously Published Models.

Background: Dexmedetomidine is a sedative and analgesic increasingly used in children supported with extracorporeal membrane oxygenation (ECMO). No data is available to describe the pharmacokinetics (PK) of dexmedetomidine in this population. Methods: We performed a single-center prospective PK study. Children <18 years old, supported with ECMO, and on a dexmedetomidine infusion as part of their management were prospectively included. PK samples were collected. Dexmedetomidine dosing remained at the discretion of the clinical team. Six population PK models built in pediatrics were selected. Observed concentrations were compared with population predicted concentrations using the PK models. Results: Eight children contributed 30 PK samples. None of the PK models evaluated predicted the concentrations with acceptable precision and bias. Four of the six evaluated models overpredicted the concentrations. The addition of a correction factor on clearance improved models' fit. Two of the evaluated models were not applicable to our whole population age range because of their structure. Conclusion: Most of the evaluated PK models overpredicted the concentrations, potentially indicating increased clearance on ECMO. Population PK models applicable to a broad spectrum of ages and pathologies are more practical in pediatric critical care settings but challenging to develop.

Pharmacokinetics of Cefepime in Children on Extracorporeal Membrane Oxygenation: External Model Validation, Model Improvement and Dose Optimization.

BACKGROUND: Cefepime is a first-line therapy for Gram-negative infections in children on extracorporeal membrane oxygenation. Cefepime pharmacokinetics (PK) in children on extracorporeal membrane oxygenation still needs to be better established. METHODS: This was a prospective single-center PK study. A maximum of 12 PK samples per patient were collected in children <18 years old on extracorporeal membrane oxygenation who received clinically indicated cefepime. External validation of a previously published population PK model was performed by applying the model in a new data set. The predictive performance of the model was determined by calculating prediction errors. Because of poor predictive performance, a revised model was developed using NONMEM and a combined data set that included data from both studies. Dose-exposure simulations were performed using the final model. Optimal dosing was judged based on the ability to maintain free cefepime concentrations above the minimal inhibitory concentration (MIC) for 68% and 100% of the dosing interval. RESULTS: Seventeen children contributed 105 PK samples. The mean (95% CI) and median (interquartile range) prediction errors were 33.7% (19.8-47.7) and 17.5% (-22.6 to 74.4). A combined data set was created, which included 33 children contributing 310 PK samples. The final improved 2-compartment model included weight and serum creatinine on clearance and oxygenator day and blood transfusion on volume of the central compartment. At an MIC of 8 mg/L, 50 mg/kg/dose every 8 hours reached target concentrations. CONCLUSIONS: Dosing intervals of 8 hours were needed to reach adequate concentrations at an MIC of 8 mg/L. Longer dosing intervals were adequate with higher serum creatinine and lower MICs.

Population Pharmacokinetics of Phenobarbital in Neonates and Infants on Extracorporeal Membrane Oxygenation and the Influence of Concomitant Renal Replacement Therapy.

The objective of this study was to describe the pharmacokinetics (PK) of intravenous phenobarbital in neonates and infants on extracorporeal membrane oxygenation (ECMO) and to provide dosing recommendations in this population. We performed a retrospective single-center PK study of phenobarbital in neonates and infants on ECMO between January 1, 2014, and December 31, 2018. We developed a population PK model using nonlinear mixed-effects modeling, performed simulations using the final PK parameters, and determined optimal dosing based on attainment of peak and trough concentrations between 20 and 40 mg/L. We included 35 subjects with a median (range) age and weight of 14 days (1-154 days) and 3.4 kg (1.6-8.1 kg), respectively. A total of 194 samples were included in the analysis. Five children (14%) contributing 30 samples (16%) were supported by continuous venovenous hemodiafiltration (CVVHDF). A 1-compartment model best described the data. Typical clearance and volume of distribution for a 3.4-kg infant were 0.038 L/h and 3.83 L, respectively. Clearance increased with age and CVVHDF. Although on ECMO, phenobarbital clearance in children on CVVHDF was 6-fold higher than clearance in children without CVVHDF. In typical subjects, a loading dose of 30 mg/kg/dose followed by maintenance doses of 6-7 mg/kg/day administered as divided doses every 12 hours reached goal concentrations. Age did not impact dosing recommendations. However, higher doses were needed in children on CVVHDF. We strongly recommend therapeutic drug monitoring in children on renal replacement therapy (excluding slow continuous ultrafiltration) while on ECMO.

Population Pharmacokinetics of IV Phenobarbital in Neonates After Congenital Heart Surgery.

OBJECTIVES: To develop a population pharmacokinetic model for IV phenobarbital in neonates following cardiac surgery and perform simulations to identify optimal dosing regimens. DESIGN: Retrospective single-center pharmacokinetic study. SETTING: Cardiac ICU at Children's Hospital of Philadelphia. PATIENTS: Consecutive neonates who received greater than or equal to one dose of IV phenobarbital and had greater than or equal to one phenobarbital concentration drawn per standard of care from June 15, 2012, to October 15, 2018. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A population pharmacokinetic model was developed using nonlinear mixed-effects modeling. Simulations were performed using the final model variables. Optimal phenobarbital loading doses were determined based on attainment of peak and maintenance concentrations between 20 and 40 mg/L. A total of 37 neonates contributed 159 pharmacokinetic samples. The median (range) weight, postmenstrual age, and postnatal age were 3.2 kg (1.3-3.8), 39 2/7 weeks (28 2/7 to 42 6/7), and 5 days (0-26 d), respectively. Twelve patients (32%) were on extracorporeal membrane oxygenation. An one-compartment model best described the data. The final population pharmacokinetic model included (1) weight and postnatal age for clearance and (2) weight, extracorporeal membrane oxygenation, and albumin for volume of distribution. In neonates not on extracorporeal membrane oxygenation, loading doses of 30 and 20 mg/kg reached goal concentration with albumin values less than or equal to 3 and 3.5 mg/dL, respectively. Loading doses of 30 mg/kg reached goal concentration on extracorporeal membrane oxygenation regardless of albumin values. Maintenance doses of 4-5 mg/kg/d reached goal concentration in all neonates. CONCLUSIONS: In neonates following cardiac surgery, phenobarbital clearance increased with postnatal age. Volume of distribution increased with extracorporeal membrane oxygenation and lower albumin values. Loading doses of 30 mg/kg on extracorporeal membrane oxygenation and 20-30 mg/kg without extracorporeal membrane oxygenation were needed to reach goal concentration based on simulations.

A retrospective comparison of phenobarbital and levetiracetam for the treatment of seizures following cardiac surgery in neonates.

OBJECTIVE: To compare the safety and efficacy of phenobarbital and levetiracetam in a cohort of neonates with seizures following cardiac surgery. METHODS: We performed a retrospective single-center study of consecutive neonates with electrographically confirmed seizures managed with antiseizure medication after cardiac surgery from June 15, 2012 to December 31, 2018. We compared the safety and efficacy of phenobarbital and levetiracetam as first-line therapy. RESULTS: First-line therapy was phenobarbital in 31 neonates and levetiracetam in 22 neonates. Phenobarbital was associated with more adverse events (P = .006). Eight neonates (14%) experienced an adverse event related to phenobarbital use, including seven with hypotension and one with respiratory depression. No adverse events were reported with levetiracetam use. The cessation of electrographic seizures was similar in both groups, including 18 neonates (58%) with seizure cessation after phenobarbital and 12 neonates (55%) with seizure cessation after levetiracetam (P = 1.0). The combined cessation rates of phenobarbital and levetiracetam when used as first- or second-line therapy were 58% and 47%, respectively (P = .47). SIGNIFICANCE: Phenobarbital was associated with more adverse events than levetiracetam, and the two drugs were equally but incompletely effective in treating electrographically confirmed seizures in neonates following cardiac surgery. Given its more acceptable safety profile and potential noninferiority, levetiracetam may be a reasonable option for first-line therapy for treatment of seizures in this population. Further prospective studies are needed to confirm these results.

Population Pharmacokinetics and Safety of Piperacillin-Tazobactam Extended Infusions in Infants and Children.

Piperacillin-tazobactam (TZP) is frequently used to treat severe hospital-acquired infections in children. We performed a single-center, pharmacokinetic (PK) trial of TZP in children ranging in age from 2 months to 6 years from various clinical subpopulations. Children who were on TZP per the standard of care were prospectively included and assigned to receive a dose of 80 mg/kg of body weight every 6 h infused over 2 h (ages 2 to 5 months) or a dose of 90 mg/kg every 8 h infused over 4 h (ages 6 months to 6 years). Separate population PK models were developed for piperacillin and tazobactam using nonlinear mixed-effects modeling. Optimal dosing was judged based on the ability to maintain free piperacillin concentrations above the piperacillin MIC for enterobacteria and Pseudomonas aeruginosa for ≥50% of the dosing interval. Any untoward event occurring during treatment was collected as an adverse event. A total of 79 children contributed 174 PK samples. The median (range) age and weight were 1.7 years (2 months to 6 years) and 11.4 kg (3.8 to 27.6 kg), respectively. A 2-compartment model with first-order elimination best described the piperacillin and tazobactam data. Both final population PK models included weight and concomitant furosemide administration on clearance and weight on the volume of distribution of the central compartment. The optimal dosing regimens in children with normal renal function, based on the piperacillin component, were 75 mg/kg/dose every 4 h infused over 0.5 h in infants ages 2 to ≤6 months and 130 mg/kg/dose every 8 h infused over 4 h in children ages >6 months to 6 years against bacteria with MICs up to 16 mg/liter. A total of 44 children (49%) had ≥1 adverse event, with 3 of these (site infiltrations) considered definitely associated with the extended infusions.

Population Pharmacokinetics of Intravenous Linezolid in Premature Infants.

BACKGROUND: The emergence of coagulase-negative staphylococci with reduced vancomycin susceptibility in some neonatal intensive care units has resulted in an increase of linezolid use. Linezolid pharmacokinetics (PK) and safety in premature infants still need to be better established. METHODS: This was a retrospective PK study. All infants who received intravenous linezolid and had linezolid plasma concentrations per standard of care were included. Linezolid concentrations were measured by high performance liquid chromatography. A population PK model was developed using nonlinear mixed effects modeling. Optimal dosing was determined based on achievement of the surrogate pharmacodynamics target for efficacy: a ratio of the area under the concentration-time curve to minimum inhibitory concentration >80. We assessed the occurrence of thrombocytopenia and lactic acidosis in relation with drug exposure. RESULTS: A total of 78 plasma concentrations were collected from 26 infants, with a median postnatal age (PNA) of 24 days (8-88) and weight of 1423 g (810-3256). A 1-compartment model described linezolid data well. The final model included PNA and weight on clearance and weight on volume of distribution. Considering an MIC90 of 1 mg/L, all infants reached an area under the concentration-time curve/minimum inhibitory concentration > 80. Although thrombocytopenia and hyperlactatemia occurred frequently, they were not sustained and were not considered related to linezolid. CONCLUSION: and was well tolerated in critically ill premature infants. PNA was the main determinant of clearance.

Patterns of Medication Exposure in Children on Extracorporeal Membrane Oxygenation: A Step in Prioritizing Future Pharmacologic Studies.

To identify medications administered to pediatric patients on extracorporeal membrane oxygenation and to review the available pharmacokinetics and pharmacodynamics literature for the most commonly administered medications. DESIGN: Retrospective single-center study. SETTING: ICUs at Children's Hospital of Philadelphia. PATIENTS: Pediatric patients supported by extracorporeal membrane oxygenation between October 1, 2014, and September 30, 2018. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Drug exposure was described according to age group (< 1 mo, 1 mo to < 2 yr, 2 to < 12 yr, and > 12 yr) and ICU (cardiac, neonatal, pediatric). The association of drug exposure with patient's characteristics was examined using one-way analysis of variance for categorical variables and linear regression for continuous variables. All pharmacokinetics and pharmacodynamics literature for the 50 most commonly administered medications on extracorporeal membrane oxygenation was reviewed, with inclusion of studies that reported dosing regimens in conjunction with pharmacokinetics or pharmacodynamics data. A total of 179 different medications were administered to 254 children. Cumulative drug exposure increased with the duration of extracorporeal membrane oxygenation from a median (interquartile) of 10 drugs (6-14) at 1 week to 31 drugs (21-45) at 5 weeks following cannulation. There were significant differences in total drug exposure between age groups and ICUs. With exclusion of in vitro studies, published literature was available to support the use of 40% (20/50) of the most commonly administered medications. Dosing guidance was available for 20% (10/50) of medications and was primarily based on simulations and retrospective studies focusing on neonates and infants. CONCLUSIONS: This study highlights specific needs for future pharmacokinetics and pharmacodynamics studies. Dosing guidelines are essential to optimize the care of critically ill children supported by extracorporeal membrane oxygenation.

Dose-Exposure Simulation for Piperacillin-Tazobactam Dosing Strategies in Infants and Young Children.

BACKGROUND: Extended piperacillin-tazobactam (TZP) infusions have been associated with favourable outcomes. There are currently no pediatric dosing recommendations. OBJECTIVES: To determine appropriate TZP dosing strategies in children 2 months - 6 years according to age and different minimal inhibitory concentrations (MICs). METHODS: Age and weight were simulated for 1000 children. Post-hoc pharmacokinetic parameter estimates were generated using published clearance and volume of distribution data. For different dosing regimens, we estimated the probability of target attainment (PTA) over a range of MICs from 4 to 128 mg/L. The pharmacodynamic (PD) target was defined as free piperacillin concentrations above the MIC for ≥ 50% of the dosing interval. A PTA ≥ 90% was defined as optimal. RESULTS: PTA decreased as MIC and age increased. In all age groups, standard dosing regimens (240-300 mg/kg/day, 0.5h infusions) failed to reach PTAs ≥ 90% at MICs ≥ 16 mg/L. Standard 0.5h infusions reached PTAs ≥ 90% at MICs up to 8 mg/L in infants > 2 to 6m. No 0.5h infusion reached PTAs ≥ 90% for MICs ≥ 4 mg/L in children > 6m. While none of the tested regimens were optimal at MICs > 16 mg/L in children > 6m, 100 mg/kg/dose every 6h as a 3h infusion reached PD target at MICs of 32 mg/L in infants > 2 to 6m. CONCLUSIONS: Up to MICs of 16 mg/L, 90 mg/kg/dose every 8h as a 2h infusion in infants > 2 to 6m and 100 mg/kg/dose every 8h as a 4h infusion in children > 6m-6y achieved PTAs ≥ 90%.