Patterns of medication exposures in hospitalized pediatric patients with acute renal failure requiring intermittent or continuous hemodialysis

Medication patterns and dosing guidance in pediatric patients supported with intermittent hemodialysis or continuous kidney replacement therapy

BACKGROUND

Hemodialysis is a life-saving technology used during periods of acute or chronic kidney failure to remove toxins, and maintain fluid, electrolyte and metabolic balance. While this technology plays an important role for pediatric patients with kidney dysfunction, it can alter the pharmacokinetic behavior of medications placing patients at risk for suboptimal dosing and drug toxicity. The ability to directly translate pharmacokinetic alterations into dosing recommendations has thus far been limited and dosing guidance specific to pediatric hemodialysis patients is rare. Despite differences in dialysis prescription and patient populations, intermittent (iHD) and continuous kidney replacement therapy (CKRT) patients are often pooled together. In order to develop evidence-based dosing guidelines, it is important to first prioritize drugs for study in each modality.

METHODS

Here we aim to identify priority drugs in two hemodialysis modalities, through: 1) Identification of hospitalized, pediatric patients who received CKRT or intermittent hemodialysis (iHD) using a machine learning-based predictive model based on medications; 2) Identification of medication administration patterns in these patient cohorts; and 3) Identification of the most commonly prescribed drugs that lack published dosing guidance.

RESULTS

Notable differences were found in the pattern of medications and drug dosing guidance between iHD and CKRT patients. Antibiotics, diuretics and sedatives were more common in CKRT patients. Out of the 50 most commonly administered medications in the two modalities, only 34% and 28% had dosing guidance present for iHD and CKRT, respectively.

CONCLUSIONS

Our results add to the understanding of the differences between iHD and CKRT patient populations by identifying commonly used medications that lack dosing guidance for each hemodialysis modality, helping to pinpoint priority medications for further study. Overall, this study provides an overview of the current limitations in medication use in this at-risk population, and provides a framework for future studies by identifying commonly used medications in pediatric CKRT and iHD patients.

Antimicrobial Dosing Recommendations in Pediatric Continuous Renal Replacement Therapy: A Critical Appraisal of Current Evidence

OBJECTIVES

Continuous renal replacement therapy (CRRT) is commonly employed in critically ill children and is known to affect antimicrobial pharmacokinetics. There is a lack of readily available, evidence-based antimicrobial dosing recommendations in pediatric CRRT. This study aims to quantify commonly used antimicrobial drugs in pediatric CRRT and identify gaps between contemporary literature-based dosing recommendations and those presented in a frequently used dosing reference.

METHODS

The Pediatric Health Information System (PHIS) database was queried from July 1, 2018 through June 30, 2021 to identify admissions in which antimicrobials were billed on the same day as CRRT. Drugs of interest were selected if at least 10% of admission involved administration on at least one CRRT day, with additional clinically important antimicrobials selected by the authors. A comprehensive literature search was performed to identify antimicrobial pharmacokinetic (PK) studies in children for each selected drug. For identified articles, dosing recommendations were extracted and compared to those in a popular tertiary dosing reference (Lexi-Comp Online database). The level of agreement of the dosing recommendations was assessed.

RESULTS

77 unique antimicrobial agents were identified amongst 812 admissions from 20 different PHIS hospitals. Fifteen antimicrobials were billed on the same day as CRRT in ≥10% of admissions, with 4 additional drugs deemed clinically relevant by the authors. Twenty PK studies were identified for these 19 drugs, and dosing recommendations were included in 8 (42.1%) of them. Seventeen agents (89.5%) had some type of CRRT-specific dosing guidance in Lexi-Comp, with only 1 directly based on a pediatric CRRT study. For the 8 agents with PK data available, Lexi-Comp recommendations matched primary literature dosing guidance in 3 (37.5%). Two (25%) lacked agreement between the Lexi-Comp and primary literature, and the remaining 3 (37.5%) had partial agreement with multiple dosing regimens suggested in the primary literature and at least one of these regimens recommended by Lexi-Comp.

CONCLUSION

Significant gaps exist in the data supporting antimicrobial dosing recommendations for children receiving CRRT. Future studies should focus on antimicrobial dosing in pediatric CRRT, emphasizing provision of robust data from which dosing recommendations can be promptly incorporated into tertiary dosing references.

Medication based machine learning to identify subpopulations of pediatric hemodialysis patients in an electronic health record database

Electronic health records (EHRs) have given rise to large and complex databases of medical information that have the potential to become powerful tools for clinical research. However, differences in coding systems and the detail and accuracy of the information within EHRs can vary across institutions. This makes it challenging to identify subpopulations of patients and limits the widespread use of multi-institutional databases. In this study, we leveraged machine learning to identify patterns in medication usage among hospitalized pediatric patients receiving renal replacement therapy and created a predictive model that successfully differentiated between intermittent (iHD) and continuous renal replacement therapy (CRRT) hemodialysis patients. We trained six machine learning algorithms (logistical regression, Naïve Bayes, k-nearest neighbor, support vector machine, random forest, and gradient boosted trees) using patient records from a multi-center database (n = 533) and prescribed medication ingredients (n = 228) as features to discriminate between the two hemodialysis types. Predictive skill was assessed using a 5-fold cross-validation, and the algorithms showed a range of performance from 0.7 balanced accuracy (logistical regression) to 0.86 (random forest). The two best performing models were further tested using an independent single-center dataset and achieved 84–87% balanced accuracy. This model overcomes issues inherent within large databases and will allow us to utilize and combine historical records, significantly increasing population size and diversity within both iHD and CRRT populations for future clinical studies. Our work demonstrates the utility of using medications alone to accurately differentiate subpopulations of patients in large datasets, allowing codes to be transferred between different coding systems. This framework has the potential to be used to distinguish other subpopulations of patients where discriminatory ICD codes are not available, permitting more detailed insights and new lines of research.

Pharmacotherapy in Critically Ill Children: A Retrospective Review of 17,199 Admissions

OBJECTIVES

Despite the ubiquitous role of pharmacotherapy in the care of critically ill children, descriptions of the extent of pharmacotherapy in critical illness are limited. Greater understanding of drug therapy can help identify clinically important associations and assist in the prioritization of efforts to address knowledge gaps. The objectives of this study were to describe the diversity, volume, and patterns of pharmacotherapy in critically ill children.

DESIGN

A retrospective cohort study was performed with patient admissions to the ICU between July 31, 2006, and July 31, 2015.

SETTING

The study took place at a single, free-standing, pediatric, quaternary center.

PATIENTS

Eligible patient admissions were admitted to the ICU for more than 6 hours and received one or more drug administration. There were a total 17,482 patient-admissions and after exclusion of 283 admissions (2%) with no documented enteral or parenteral drug administration, 17,199 eligible admissions were studied.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The 17,199 eligible admissions were admitted to the ICU for 2,208,475 hours and received 515 different drugs. The 1,954,171 administrations were 894,709 (45%) enteral administrations, 998,490 (51%) IV injections and 60,972 (3%) infusions. Infusions were administered for 4,476,538 hours. Twelve-thousand two-hundred seventy-three patients (71%) were administered five or more different drugs on 80,943 of patient days (75%). The 10 most commonly administered drugs comprised of 834,441 administrations (43%).

CONCLUSIONS

Drug administration in the ICU is complex, involves many medications, and the potential for drug interaction and reaction is compounded by the volume and diversity of therapies routinely provided in ICU. Further evaluation of polytherapy could be used to improve outcomes and enhance the safety of pharmacotherapy in critically ill children.

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.

Variation of the prevalence of pediatric polypharmacy: A scoping review

PURPOSE

To examine the range of prevalence of pediatric polypharmacy in literature through a scoping review, focusing on factors that contribute to its heterogeneity in order to improve the design and reporting of quality improvement, pharmacovigilance, and research studies.

METHODS

We searched Ovid Medline, PubMed, EMBASE, CINAHL, Ovid PsycINFO, Cochrane CENTRAL, and Web of Science Core Collection databases for studies with concepts of children and polypharmacy, along with a hand search of the bibliographies of six reviews and 30 included studies. We extracted information regarding study design, disease conditions, and prevalence of polypharmacy.

RESULTS

Two hundred eighty-four studies reported prevalence of polypharmacy. They were more likely to be conducted in North America (37.7%), published after 2010 (44.4%), cross-sectional (67.3%), in outpatient settings (59.5%). Prevalence ranged from 0.9% to 98.4%, median 39.7% (interquartile range [IQR] 22.0%-54.0%). Studies from Asia reported the highest median prevalence of 45.4% (IQR 27.3%-61.0%) while studies from North America reported the lowest median prevalence of 30.4% (IQR 14.7%-50.2%). Prevalence decreased over time: median 45.6% before 2001, 38.1% during 2001 to 2010, and 34% during 2011 to 2017. Studies involving children under 12 years had a higher median prevalence (46.9%) than adolescent studies (33.7%). Inpatient setting studies had a higher median prevalence (50.3%) than studies in outpatient settings (38.8%). Community level samples, higher number and duration of medications defining polypharmacy, and psychotropic medications were associated with lower prevalence.

CONCLUSIONS

The prevalence of pediatric polypharmacy is high and variable. Studies reporting pediatric polypharmacy should account for context, design, polypharmacy definition, and medications evaluated.

Defining pediatric polypharmacy: A scoping review

OBJECTIVES

Lack of consensus regarding the semantics and definitions of pediatric polypharmacy challenges researchers and clinicians alike. We conducted a scoping review to describe definitions and terminology of pediatric polypharmacy.

METHODS

Medline, PubMed, EMBASE, CINAHL, PsycINFO, Cochrane CENTRAL, and the Web of Science Core Collection databases were searched for English language articles with the concepts of "polypharmacy" and "children". Data were extracted about study characteristics, polypharmacy terms and definitions from qualifying studies, and were synthesized by disease conditions.

RESULTS

Out of 4,398 titles, we included 363 studies: 324 (89%) provided numeric definitions, 131 (36%) specified duration of polypharmacy, and 162 (45%) explicitly defined it. Over 81% (n = 295) of the studies defined polypharmacy as two or more medications or therapeutic classes. The most common comprehensive definitions of pediatric polypharmacy included: two or more concurrent medications for ≥1 day (n = 41), two or more concurrent medications for ≥31 days (n = 15), and two or more sequential medications over one year (n = 12). Commonly used terms included polypharmacy, polytherapy, combination pharmacotherapy, average number, and concomitant medications. The term polypharmacy was more common in psychiatry literature while epilepsy literature favored the term polytherapy.

CONCLUSIONS

Two or more concurrent medications, without duration, for ≥1 day, ≥31 days, or sequentially for one year were the most common definitions of pediatric polypharmacy. We recommend that pediatric polypharmacy studies specify the number of medications or therapeutic classes, if they are concurrent or sequential, and the duration of medications. We propose defining pediatric polypharmacy as "the prescription or consumption of two or more distinct medications for at least one day". The term "polypharmacy" should be included among key words and definitions in manuscripts.

Hospitalizations for Respiratory Syncytial Virus and Vaccine-Preventable Infections in the First 2 Years After Pediatric Liver Transplant

OBJECTIVES

To examine in liver transplant recipients at centers participating in the Pediatric Health Information System dataset the number of hospitalizations for respiratory syncytial virus (RSV) and vaccine-preventable infections (VPIs) in the first 2 years after transplantation, morbidity and mortality associated with these hospitalizations, and costs associated with these hospitalizations.

STUDY DESIGN

A retrospective cohort study of patients <18 years of age who underwent liver transplantation at a Pediatric Health Information System center between January 1, 2004, and December 31, 2012. Hospitalizations for RSV/VPIs during the first 2 years post-transplant were ascertained using International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes. Data were collected on clinical care, outcomes, and costs during these hospitalizations.

RESULTS

There were 2554 liver transplant recipients identified; 415 patients (16.3%) had 544 cases of RSV/VPIs. RSV, rotavirus, and influenza were the most common infections resulting in hospitalization. Ninety-two patients (3.6%) had RSV/VPI during their transplant hospitalization. Transplant hospitalizations complicated by RSV/VPI were longer (44 days vs. 21 days; P < .001), had higher rejection rates (37% vs. 26%; P = .02), and were more expensive ($259 697 vs. $190 860; P < .001). Multivariate analyses identified age <2 years at transplant (P < .001) and multivisceral recipient (P = .04) as predictors of a hospitalization for RSV.

CONCLUSIONS

VPIs occurred in 1 of 6 liver transplant recipients in the first 2 years post-transplant, a significantly higher rate than in the general pediatric population. These hospitalizations had substantial morbidity, mortality, and costs, demonstrating the importance of vaccinating patients before transplantation.

Extracorporeal therapies in pediatric severe sepsis: findings from the pediatric health-care information system

Introduction

Pediatric severe sepsis (PSS) continues to be a major health problem. Extracorporeal therapies (ETs), defined as extracorporeal membrane oxygenation (ECMO) and RRenal replacement therapyenal replacement therapy (RRT), are becoming more available for utilization in a variety of health conditions. We aim to describe (1) rates of utilization of ET in PSS, (2) outcomes for PSS patients receiving ET, and (3) epidemiologic characteristics of patients receiving ET.

Methods

We conducted a retrospective review of a prospectively collected database. Data from the Pediatric Health Information System (PHIS) database collected by the Children’s Hospital Association (CHA) from 2004–2012 from 43 US children’s hospitals’ pediatric intensive care units (PICUs) were used. Patients with PSS were defined by (1) International Classification of Diseases, 9th Revision (ICD-9) codes reflecting severe sepsis and septic shock and (2) ICD-9 codes of infection and organ dysfunction as defined by updated Angus criteria. Among the patients with PSS, those with a PHIS flag of ECMO or RRT were identified further as our main cohort.

Results

From 2004 to 2012, 636,842 patients were identified from 43 hospitals, and PSS prevalence was 7.7 % (49,153 patients). Nine point eight percent (4795 patients) received at least one form of ET, and the associated mortality rate was 39 %. Mortality rates were 47.8 % for those who received ECMO, 32.3 % in RRT, and 58.0 % in RRT + ECMO. Underlying co-morbidities were found in 3745 patients (78.1 %) who received ET (81 % for ECMO, 77.9 % in RRT, and 71.2 % in those who received both). There was a statistically significant increase in ECMO utilization in patients with at least three organ dysfunctions from 2004 to 2012 (6.9 % versus 10.3 %, P < 0.001) while RRT use declined (24.5 % versus 13.2 %, P < 0.001). After 2009, there was a significant increase in ECMO utilization (3.6 % in 2004–2008 versus 4.0 % in 2009–2012, P = 0.004). ECMO and RRT were used simultaneously in only 500 patients with PSS (1 %).

Conclusions

ETs were used in a significant portion of PSS patients with multiple organ dysfunction syndrome (MODS) during this time period. Mortality was significant and increased with increasing organ failure. ECMO use in PSS patients with MODS increased from 2004 to 2012. Further evaluation of ET use in PSS is warranted.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-015-1105-4) contains supplementary material, which is available to authorized users.