Prescribing a Green Future: A Review of Antimicrobial Waste in Pediatric Hospitals and Practices to Promote Healthcare Sustainability

Abstract

Pediatric hospitals are uniquely positioned to be impacted by antimicrobial waste. To explore this issue, we reviewed the current literature to identify the reasons, costs, and potential solutions to waste. Identified reasons for waste included weight-based dosing, medication order changes due to changing patient status, loss or expiration of doses, and medication errors. The cost of waste included financial costs, promotion of antimicrobial resistance, and generation of greenhouse gases. Proposed interventions to reduce waste included an early switch from intravenous to oral administration, required stop dates, standardized dosing times, and optimization of the pharmacy batching process. However, additional studies are needed to assess the potential correlation between these proposed interventions and waste reduction. Antimicrobial stewardship programs have been identified as a group that can play a crucial role in partnering to implement these interventions to potentially reduce antimicrobial waste and promote better healthcare sustainability.

INTRODUCTION

Hospital-generated antimicrobial waste has been highlighted in several recent publications, which have reported worrying quantities of unused medications that are then thrown away [1, 2]. Pediatric hospitals are particularly vulnerable to producing antimicrobial waste due to several unique challenges, including weight-based dosing, preparation differences based on patient age, and lack of pediatric-specific commercial products [1–4]. Additional drivers of waste include dispensing, handling, and disposal of unused, expired, or patient-specific medication doses [1–3, 5].

The resulting antimicrobial waste carries both financial and environmental costs [1, 2, 6]. Additionally, hospital-generated antimicrobial waste negatively impacts global health through the development of antimicrobial resistance, the promotion of drug shortages, and the emission of greenhouse gases [1, 2, 7]. To combat these costs, the implementation of sustainable practices within hospital pharmacy departments to reduce antimicrobial waste has become increasingly crucial [8, 9].

This review article explores the current literature surrounding pharmaceutical waste, with a focus on antimicrobial waste in pediatric healthcare settings. Finally, this article reviews proposed solutions for mitigating waste and provides examples of how antimicrobial stewardship programs (ASPs) can help lead the way in promoting better healthcare sustainability.

METHODS

An initial identification of articles was conducted through a search of the published literature through the National Library of Medicine (PubMed) using the search terms (“pharmaceutical” [medical subject heading (MeSH) terms] OR “medication” [all fields]) AND (“waste” [MeSH Terms] OR “sustainability” [all fields]) AND (“child”[MeSH Terms] OR “child*”[all fields]) OR (“pediatric”[MeSH Terms] OR “children’s hospital*”[all fields]) AND (“antimicrobial” [MeSH Terms] OR “antibiotic” [all fields]). To supplement the search strategy, reference lists from all identified studies and key review articles on pharmaceutical waste and healthcare sustainability were subsequently reviewed. All abstracts in English were included, and no date limitations were applied. Articles were excluded if the full article was unavailable through PubMed. If a study did not occur in the hospital setting, it was not utilized.

Data were collected for the following variables: author, publication year, study setting, study design, and pharmaceutical waste type. Conclusions were included and results summarized in Table 1.

Table 1.

Published Literature Regarding Pharmaceutical Waste in Pediatric Healthcare Systems

Author/Year	Study Setting	Study Design	Waste Type	Conclusions
Aeng, ES (2020)	12 hospital sites across Fraser Health Authority in British Columbia from January 1 to 31, 2018	Retrospective chart review	Waste from fluticasone and salmeterol metered-dose inhalers (MDIs) identified	When medications are only available in multiple-dose formulations, there is an increase in drug waste and thus unnecessary healthcare expenditure.
Almeida, MA (2016)	4 pediatric units within a tertiary care hospital in Brazil	Descriptive and observational study design	All pharmaceutical waste over a 3-month period	Antimicrobials were the most frequently disposed pharmaceutical class of medication noted in this study, with the surgical unit having the highest proportion of antimicrobial waste.
Bucak, I (2020)	Pediatric emergency department in a university hospital in Turkey from January 1, 2017 to April 30, 2017	Prospective real-time analysis of drug waste	All IV and IM pharmaceutical waste over a 4-month period	Approximately 43% of the total medication volume dispensed was wasted.
Davis, S (2017)	Free-standing children’s hospital in the United States from January 2014 to August 2014	Process improvement assessing implementation of a workflow management system	All IV and PO medication errors over two 8-month periods, also capturing reduction in waste	Implementation of a new pharmacy workflow management system that included improved communication regarding order changes and discontinuations led to significant reductions in medication errors and waste.
Fan, KL (2023)	3 free-standing children’s hospitals in the United States from January 1, 2020, through December 31, 2021	Single center, retrospective review	Inpatient antibiotic waste over a 2-year span of time	On average there were 80 antibiotic doses wasted per day, associated with an estimated cost of $255 503. More than half of the doses were wasted near the time of hospital admission or discharge. System changes such as automated stop dates, prior authorization, and early discharge planning may reduce waste.
Hintzen, BL (2009)	Academic medical center in the United States	Process improvement	Waste from all sterile products	Noted an annual savings of $289 256 in waste reduction after implementing lead methodology into pharmacy workflow.
Hollis, K (2021)	Children’s Hospital in Canada	Process improvement	Waste from compounded IV medications or discarded in single-use vials over three 1-week periods	Implementation of 6-h beyond-use dating for IV medication compounding increased medication waste to an estimated volume and cost of 68 875 mL and $70 456 per year. Optimization of vial sizes purchased and utilized reduced waste volume by 34%.
L’Hommedieu, T (2010)	Free-standing children’s hospital in the United States over a 30-day period	Process improvement	All IV medications wasted over two 7-day time periods	Adjustments to pharmacy medication processes, including frequent preparation of batches, resulted in a reduced number of wasted doses from 191 to 122 per day.
Li, J (2023)	Free-standing children’s hospital in China	Process improvement	Estimated waste avoided using a vial-sharing strategy for 10 antibiotics over 1 year	Use of a vial-sharing (batching) strategy and adjusted medication payment model resulted in a 35% reduction in antibiotic waste and patient cost. Antibiotics with higher purchasing costs, frequent dosing intervals, and/or dosage formulations that differ from frequently prescribed doses have the largest potential for waste and cost reduction.
MacBrayne, CE (2019)	Free-standing children’s hospital in the United States from January 1 to December 31, 2016	Single center, retrospective chart review	Inpatient antimicrobial waste in 1 year	Noted that 9% of all antimicrobials dispensed were wasted with a resultant cost of approximately $100 000. Medication order changes or discontinuations, misplacement of doses, or patient discharge were the most frequent reasons for waste.
Nava-Ocampo, A (2004)	Anesthesia department in a pediatric hospital in Mexico	Prospective, blinded, observational study design	All pharmaceutical waste for patients undergoing elective or emergency surgical procedures	Anesthetic medication waste was common and more than 80% of all doses were wasted for 5 medications typically used during anesthesia.
Toerper, M (2014)	205-bed pediatric unit within an academic hospital in the United States, from June 1 to September 2012	Pre- and post-intervention analysis	All pharmaceutical waste from a batching process over a 3-month period	A once-daily medication preparation batching strategy wasted 29% of doses and an estimated $686 752 per year. A 3-times daily batching strategy reduced medication waste by 31%. Adjusting the frequency and time of medication batch preparations is an effective strategy to reduce pharmaceutical waste.

RESULTS

Study Settings and Populations

Search and screening strategies are shown in Figure 1. Twelve studies were found in the literature discussing pharmaceutical waste in either pediatric or adult healthcare settings for inclusion in this review (Table 1). Seven studies were prospective or retrospective research and 5 were process improvement initiatives. Six studies were conducted in the United States, with the others in Mexico, Turkey, British Columbia, Brazil, Canada, and China. Four of these studies either focused on antimicrobial waste exclusively or included antimicrobials as a subgroup in their analysis (Table 2).

Table 2.

Reasons, Costs, and Proposed Solutions Among Studies Specifically Addressing Antimicrobial Waste

Study	Reasons for Waste	Costs of Waste	Proposed Solutions
Almeida, MA (2016)	Limited pediatric dosage forms Lack of awareness/education regarding proper waste disposal processes Inadequate supplies to follow recommended processes	Environmental contamination caused by noncompliance with waste disposal processes	Educate healthcare teams on proper waste disposal processes and their importance Dispensing of individualized doses Legislation to promote and enforce healthcare waste reduction and proper disposal
Fan, KL (2023)	Order changes after dose preparation, particularly during transitions of care (within 48 h of admission and near the time of discharge)	Carbon emissions secondary to waste of plastic syringes, antibiotics, and carrier fluid Financial cost (>$120 000 annually) Loss of limited product during drug shortages	Automatic stop dates on empiric antibiotic orders Encourage early discharge planning to proactively place stop dates on antibiotic orders prior to discharge Prior authorization for select agents
Li, J (2023)	Patient-specific dosing with limited pediatric dosage formulations	Financial cost to healthcare systems and patients Occupational and environmental exposure of drug waste	Frequent batching to allow for vial sharing Identify and prioritize batching for commonly prescribed, high-cost antimicrobials with frequent dosing and prescribed doses that differ from available dosage formulations Unique charge models for batched medications
MacBrayne, CE (2013)	Order changes after dose preparation due to clinical changes or patient discharge Lost doses	Financial cost (>$100 000 annually) Wasted medical supplies and antimicrobials, including those on shortage	Electronic queue for high-waste or high-cost agents in the pharmacy to communicate order changes Standardization of doses and administration times Require order end dates Additional pharmacist monitoring in high-use units

Figure 1.

Figure detailing search and screening strategies within Pubmed.

Studies on Antimicrobial Waste

The published studies identified many causes of waste. Excess drug volume due to patient-specific dosing and limited available dosage formulations were noted as a contributory cause in all studies. One study estimated an annual intravenous (IV) medication waste volume of over 31 000 mL due to excess product in single-use vials [10]. After medication dispensing, order discontinuation or modification were frequent sources of antimicrobial waste in inpatient pediatric units. These occurred most frequently due to modifications to empiric antibiotic therapy near the time of patient admission or modifications to therapy at the time of discharge [1, 2]. In addition to hospital units, the emergency department and operating rooms were identified as locations with high volumes of waste [11, 12]. Additional reasons for waste were expired medications, lost doses, and medication errors [1, 2, 13, 14].

Several costs of antimicrobial waste were explored. Financial cost associated with waste to the healthcare system was described or noted as a concern in several studies. Three studies estimated the costs of waste at their institution to be greater than $100 000 per year [1, 2, 6]. Li and colleagues further demonstrated that the financial cost of waste may also directly affect patients [3]. Outside of financial implications, 2 studies noted that waste was common in antimicrobials on shortage, therefore further reducing the supply of first-line agents and potentially resulting in suboptimal care for other patients [1, 2]. Occupational and environmental exposure were emphasized as potential consequences of waste handling and disposal.

Interventions to target many of the identified underlying causes of waste were described. Changes to the medication preparation process such as adjustments in the number or time(s) of batched medication preparation, increased communication with the pharmacy, or optimization of vial sizes were most commonly assessed or suggested [1, 3, 6, 10, 11, 13–15]. Proactive efforts at the point of order entry, such as standardization of doses or administration times, were also suggested to allow for the re-use of unadministered doses [1]. Additionally, the implementation of automatic stop dates for empiric antimicrobials and preemptive adjustment of orders prior to patient discharge were proposed to combat waste generated near transitions of care [1, 2]. Prior authorization to ensure proper use of select agents could also be used to mitigate financial loss related to high-cost agents [2]. One study focused on opportunities to improve processes after waste is generated, proposing that increased awareness of proper waste disposal processes may reduce occupational and environmental exposure [5].

DISCUSSION

Reasons for Waste

The reasons for antimicrobial waste are multifactorial and easiest to consider along the life cycle of a treatment course in the hospital setting. Medication orders, whether placed in an electronic medical record (EMR) or on paper, eventually lead to a dispensed product from either a central pharmacy or an automated dispensing unit. It is assumed that the latter scenario does not generate much waste due to operations or workflow, since these automated units are often located in close physical proximity to patients and medication doses are often withdrawn shortly before administration. The more complex process occurs when a medication is dispensed from the central pharmacy using a batching process.

Reasons for Waste: Batching of Medication

For any hospital, but especially pertinent to pediatric hospitals, understanding how the batching process works is essential to understanding the reasons for waste generation. While dosing for adult patients is usually standardized, pediatric dosing is weight-based and varies for each patient. In addition, due to weight-based dosing, standard concentrations often require dilution to create a volume that can be administered to a pediatric patient.

Batching is the process by which a pharmacy optimizes operational efficiency through the preparation of all scheduled medication doses for an upcoming time window, typically several hours ahead of when the medications are due to be administered. This process ensures medications are available when needed while also allowing the pharmacy to respond to new medication requests or emergent orders promptly. Depending on the hospital, the pharmacy could have any number of batch times (eg, every 2, 4, 6, or 12 h), although it is important to note that there is no defined best practice for the frequency and number of batches a pharmacy prepares. It has been noted that batching in any capacity creates operational efficiency for pharmacies, but can also have significant potential for waste generation [3, 6, 10, 15]. To our knowledge, there has never been a comparison of pharmaceutical waste generation between adult and pediatric hospitals, but since patient-specific doses are less common in adult patients, less waste is thought to be generated.

Fan and colleagues identified wasted antibiotic doses that resulted from the batching process used in the pharmacy. They noted that most wasted doses occurred in the first 48 h or last 24 h of a hospital stay with 58 607 doses of antibiotic wasted during the study period, which equated to an average of 80 doses per day [2]. If we consider the timeline of a patient’s stay, we can see how waste can occur during these periods, from batching or otherwise.

The following are examples of common scenarios in which the batching process may lead to waste generation: (1) Antimicrobial therapy changes due to the clinical status of the patient; thus, any already prepared doses are wasted. (2) As microbiological culture results return and antimicrobial therapy is adjusted to target a particular pathogen, additional antimicrobial doses may be wasted. (3) A patient’s clinical status improves, and when they transition from the ICU to the floor, prepared medications are sometimes left upon transfer requiring additional doses to be prepared. (4) As a patient prepares for discharge, they may transition to a PO formulation. The pharmacy, unaware of the impending discharge, will likely prepare the next scheduled IV dose that will not be given. These scenarios highlight that waste is often generated when antimicrobials are changed or discontinued due to change in patient status, pending culture results, or discharge home [1, 2].

Cost of Antimicrobial Waste

To our knowledge, the cost of antimicrobial waste in a freestanding pediatric hospital was first described by MacBrayne and colleagues, who estimated an annual cost of $100 000 in drug cost based on data from 2016 that showed there were 10 062 wasted doses [1]. Building on this work, Fan and colleagues found that their hospital generated 58 607 wasted doses over a 2-year period from 2020 to 2021, leading to an estimated $127 751 annual cost of waste [2]. This cost estimate considered the cost of drugs plus an estimated cost of syringes wasted, assuming 1 syringe per dose prepared, and the cost of saline needed for compounding.

Cost of Antimicrobial Waste: Medication Charges

In hospital pharmacy settings, the point at which patients are charged for the medications they are receiving may differ. Some hospitals charge the patient’s account on the dispensation of the medication from the pharmacy vs others who charge based on documentation that the medication was administered to the patient. Due to this, wasted doses can have a significant financial impact to either the healthcare system or the patient and family. In the scenario where the hospital system is charging the patient for the medications at the point when they are dispensed from the pharmacy, the patient and family may be paying for doses that were never received. On the contrary, in the scenario where the patient is charged only on administration and a dose is not given, the hospital system is losing revenue due to that dose being wasted.

Cost of Antimicrobial Waste: Antimicrobial Resistance

Unfortunately, the cost of pharmaceutical waste goes beyond financial considerations alone and has been observed in the development of antimicrobial-resistant organisms. This is due to the disposal of unused medications down sink drains, allowing medications to enter our water systems. A systematic review by Kizny Gordon and colleagues looked at 32 reports of carbapenem-resistant organisms associated with water reservoirs (eg, sinks, drains) in hospitals over a 20-year period [16]. They concluded that the use of sinks for improper disposal of clinical waste was associated with at least 3 carbapenem-resistant organism infection outbreaks in patients [7, 17, 18]. An additional study by Constantinides and colleagues performed whole genome sequencing on 439 total isolates of Escherichia coli or Klebsiella spp. from hospital sinks and compared results to 46 contemporaneously collected isolates from patients [9]. This data highlighted that sinks within hospitals may contribute to 10% of infections over a given time. With the frequency of wasted medications, including antimicrobials, that are currently disposed of down the sinks, 1 can extrapolate that the water system exposure to unnecessary antimicrobials is leading to increased colonization with antimicrobial-resistant organisms.

Cost of Antimicrobial Waste: Environmental Sustainability

Beyond the confines of the individual hospital or hospital system, waste plays an important role in global environmental sustainability. Healthcare operations in the United States have been shown to account for approximately 8%–10% of the greenhouse gas emissions in this country, largely driven by the supply chain for goods and services [19, 20]. Due to this, Singh and colleagues recently proposed a plan for “net-zero healthcare” that included mandatory adoption of standardized metrics and reporting for hospital system climate emissions [21]. Solid medical waste, including antimicrobial waste, has been noted to contribute to overall greenhouse gas emissions in several ways. First, incinerating or autoclaving waste prior to disposal in a landfill contributes to greenhouse gas emissions. Second, waste in landfills is associated with methane production, which accounts for 16% of global emissions and is 28 times more potent as a greenhouse gas than carbon dioxide [22, 23]. As previously mentioned, in 2013 it was estimated that the healthcare sector in the United States was responsible for approximately 8%–10% of greenhouse gas emissions, which is much higher than the healthcare sectors of other countries such as England, Australia, and Canada, which are responsible for 3%, 7%, and 5%, respectively [19, 20].

To our knowledge, there is a lack of published data quantifying the greenhouse gas emissions from antimicrobial waste in hospital settings. To bridge this gap, as antimicrobial stewards, we can measure the environmental impact of waste by collecting estimates for the total weight of waste, understanding how our hospital systems process waste, and utilizing free waste calculators, such as the Mazzetti Wastecare Calculator (designed to be used for large amounts of waste disposal) and the Environmental Protection Agency (EPA) Greenhouse Gas Equivalencies Calculator, to convert the calculated waste into estimated emissions output and carbon dioxide equivalents, such as miles driven by a gasoline-powered car or number of houses using electricity for a year [24, 25].

Potential Solutions to Reduce Waste

ASPs can play a crucial role in supporting the implementation of interventions designed to reduce antimicrobial waste. The Centers for Disease Control and Prevention (CDC) defines antimicrobial stewardship as “the effort to measure and improve how [antimicrobials] are prescribed by clinicians and used by patients” [26]. While ASPs often focus on patient-centered outcomes, such as reducing the development of antimicrobial resistance and adverse drug effects, interventions aimed at optimizing antimicrobial use can also benefit healthcare sustainability. Proposed solutions where ASPs can help to reduce waste are detailed in Table 3.

Table 3.

Key Problems Leading to Antimicrobial Waste and Proposed Solutions

Problem	Solution
IV formulations are expensive and frequently wasted	ASPs should have robust IV-to-PO transition programs for highly bioavailable drugs
Pharmacies may be unaware of treatment plans and prepare unnecessary doses	ASPs should ensure that all antimicrobial orders utilize stop dates
Pharmacies may be unaware of patients being discharged or doses of medications being changed due to clinical factors	ASPs should work to standardize dosing times, especially for once-daily medications that allow for rounds to be completed prior to the next dose being due
Batching process leads to wasted doses due to early preparation of doses	ASPs should work to remove antimicrobials that are expensive, infrequently used, or require therapeutic drug monitoring from the batching process
Wasted patient-specific doses cannot be repurposed for another patient	ASPs should participate in the development of clinically appropriate dose rounding and/or dose banding protocols

Potential Solution: IV to PO Switch

One example of this is promoting the transition from IV to PO route of administration for highly bioavailable antimicrobials. Rodger and colleagues described a quality improvement initiative that incorporated healthcare staff education, EMR prompts, and pharmacy prospective audit and feedback to encourage IV to PO switch whenever clinically appropriate [27]. Compared to baseline, they observed a 44% median reduction in IV-defined daily doses for the targeted antimicrobial agents during the first 2 years after the implementation of the initiative. From the preference of PO over IV metronidazole alone, the investigators estimated a reduction of 1200 IV administrations and 600 nursing hours saved each month. Based on previous benchmarks, this single change could also save 1200 syringes (>10 kg of waste) per month [2]. In addition to saving syringes, reducing the use of IV medications secondarily reduces disposal of personal protective equipment which must be discarded each time a pharmacy employee enters and exits a sterile IV room suite. Thus, while the authors primarily discussed savings on syringes, waste reduction can also be extrapolated to other supplies required to prepare IV medications that are not needed to dispense oral medications.

Potential Solution: Antimicrobial Stop Dates

Another key antimicrobial stewardship intervention that can help reduce pharmaceutical waste is increased utilization of stop dates for antimicrobial orders. Stop dates provide a prespecified end date and time, which ensures that the pharmacy will not prepare extra doses. Entering a stop date once the appropriate duration has been determined also eliminates the need for providers to manually discontinue orders, thus decreasing accidental administration of additional doses. Antimicrobial stewardship teams may choose to develop institutional treatment guidelines, perform prospective audit and feedback, and create order sets to help providers select an optimal duration of therapy for a particular infection and enter stop dates accordingly.

Potential Solution: Pharmacy Operations

Antimicrobial stewardship teams can collaborate with their pharmacy operations colleagues to identify opportunities to reduce antimicrobial waste that occurs as part of the pharmacy workflow. Standardized administration times, particularly for IV antimicrobials that are administered less frequently (eg, every 24 h, 3 times weekly, or as a single dose), may allow the pharmacy to minimize the number of drug vials that are required to prepare weight-based doses for multiple patients at 1 time. In addition, moving these standardized administration times to the early afternoon may limit the impact of changes to antimicrobial orders made during routine morning rounds, while still facilitating timely hospital discharge if receipt of a dose is needed prior to going home.

Other automated methods to minimize discarded weight-based drugs include dose rounding (doses are rounded to the nearest vial size if they fall within a predefined safe percentage of the intended dose) and dose banding (doses that fall within a specified range are adjusted to fit predefined standard doses). Nass and colleagues published a hypothetical clinical scenario of dose rounding for the antineoplastic agent bortezomib [28]. This example showed that for a 75 kg patient receiving a dose of bortezomib 70 mg/m² once per week, rounding from the exact dose of 134 mg/week to 130 mg/week saved 11% in discarded drug cost while still providing 97% of the exact prescribed dose. Likewise, dose rounding for commonly used pediatric medications could allow an unused dose to be given to another patient of a similar (but not identical) weight before the preparation reaches its beyond-use date.

Potential Solution: Education

An essential component of antimicrobial stewardship is the provision of education regarding the benefits of appropriate antimicrobial use and the corresponding risks of antimicrobial misuse. Prescribers and patients alike are more likely to engage with programs to minimize antimicrobial waste if they clearly understand why it is important to do so. As a result, ASPs should monitor reductions in pharmaceutical waste as part of their quality improvement outcomes and report this information to administrators and clinicians at their institutions.

CONCLUSIONS

Pediatric hospitals have many unique challenges that predispose them to antimicrobial waste generation, which negatively impact patients and hospital systems alike through financial and environmental costs. ASPs are positioned to play a crucial role in helping to mitigate waste, thus reducing antimicrobial resistance and creating more sustainable healthcare systems. While proposed interventions for waste reduction are promising, further studies are needed to show efficacy and establish best practices to create a greener future.

Notes

Financial support. This work was supported by a grant from the National Institutes of Health [grant T32 AI106688 to ASP].

Potential conflicts of interest. All authors: No reported conflicts.

Data Availability

All data generated for this manuscript are presented in Table 1.