Efficacy and safety of continuous infusions with elastomeric pumps for outpatient parenteral antimicrobial therapy (OPAT): an observational study

Feasibility of 24 h continuous-infusion cefiderocol administered by elastomeric pump in attaining an aggressive PK/PD target in the treatment of NDM-producing Klebsiella pneumoniae otomastoiditis

Objectives

Cefiderocol has emerged as a key treatment for managing MDR infections, and its time-dependent pharmacodynamics are optimized by prolonged infusion to maintain time above the MIC (T  > MIC). Whereas recent stability studies have shown cefiderocol remains stable up to 72 h in elastomeric pumps, its use in 24 h continuous infusions (CIs) for outpatient parenteral antibiotic therapy (OPAT) is undocumented. This case highlights its suitability for 24 h CI via elastomeric pumps in an OPAT setting, supported by therapeutic drug monitoring (TDM) to ensure optimal treatment efficacy.

Patient/case description

A 31-year-old male developed right-sided otomastoiditis caused by Klebsiella pneumoniae producing New Delhi MBL (NDM). Given the resistance profile and the need for prolonged therapy, cefiderocol was initiated at a daily dose of 6 g, administered by 24 h CI using an elastomeric pump. TDM was performed on Days 17 and 45 to assess plasma concentrations.

Results

TDM confirmed steady-state concentrations (C ss 25.2-28.1 mg/L), achieving optimal pharmacokinetic/pharmacodynamic (PK/PD) target attainment such as 100% T  > 4-6 MIC (free [f]C ss/MIC 10.58-11.80). Significant clinical improvement avoided the need for planned surgery, with no adverse events reported from the venous catheter, antibiotic therapy or elastomeric pump.

Conclusions

This approach underscores the feasibility and efficacy of cefiderocol administered by 24 h CI by means of an elastomeric pump and supported by real-time TDM in achieving an aggressive PK/PD target for the treatment of otomastoiditis due to NDM-producing K. pneumoniae.

Antibiotic Stability and Feasibility in Elastomeric Infusion Devices for OPAT: A Review of Current Evidence

Background/Objectives: Elastomeric infusion pumps have emerged as a transformative tool in outpatient parenteral antimicrobial therapy (OPAT), enabling continuous intravenous administration outside hospital settings, enhancing patient autonomy, reducing healthcare costs, and playing a role in antimicrobial stewardship. This aim of this review is to update current evidence on antibiotic stability in elastomeric infusion pumps, analyzing environmental factors, clinical efficacy, and practical challenges associated with OPAT implementation. Methods: A narrative review was conducted using PubMed and the Cochrane Library, focusing on studies published between 2022 and 2025. Included studies assessed antibiotic stability in elastomeric pumps under real-world and laboratory conditions, examining factors such as temperature sensitivity, light exposure, and material interactions. Results: Findings indicate considerable variability in antibiotic stability, with some agents maintaining prolonged efficacy while others degrade rapidly under certain conditions. Antibiotics with greater stability are better suited for OPAT, whereas those prone to degradation present challenges for continuous infusion. Clinical studies report favorable treatment outcomes, including high cure rates and manageable adverse event profiles. However, discrepancies between laboratory-controlled conditions and real-world settings highlight the necessity for more comprehensive stability evaluations to ensure optimal antibiotic selection and administration in OPAT programs. Conclusions: Optimizing antibiotic formulations, standardizing stability protocols, and advancing elastomeric pump technologies are essential for enhancing OPAT effectiveness. Future research should focus on real-world simulation studies and refining device materials to expand the range of stable antibiotics, ensuring safer and more efficient outpatient antimicrobial therapy.

Fusobacterium necrophorum septic arthritis of the hip: A case-report and literature review

INTRODUCTION

Fusobacterium necrophorum is a rare but significant cause of septic arthritis, typically following oropharyngeal infections in adolescents. This anaerobic pathogen, commonly associated with Lemierre's syndrome, can lead to joint infections, posing risks for severe morbidity if diagnosis and treatment are delayed. Awareness and timely intervention are essential for preventing long-term joint damage.

CASE REPORT

We report the case of a 19-year-old woman who developed high fever and acute right hip pain one week after a sore throat. Imaging revealed septic arthritis, with F. necrophorum identified in both blood and synovial fluid cultures. She received intravenous piperacillin/tazobactam, followed by outpatient parenteral therapy through an elastomeric pump, achieving full recovery. This case adds to the 42 cases documented in our literature review, reinforcing the need for prompt antimicrobial therapy.

CONCLUSION

Fusobacterium-induced septic arthritis, though uncommon, should be considered in young patients presenting with joint infections post-pharyngitis. Early diagnosis and targeted antimicrobial therapy, particularly with β-lactamase inhibitors, are critical for effective management and preventing joint sequelae.

Patient-reported outcome measures in an outpatient parenteral antimicrobial therapy program: a prospective cohort study

OBJECTIVES

To evaluate the improvements in the mean Short Form-36 (SF-36) score (95% CI) from predischarge to postdischarge among prospective participants of a Swiss Outpatient Parenteral Antimicrobial Therapy (OPAT) programme using Patient Reported Outcomes.

DESIGN

Prospective cohort study.

SETTING

A public tertiary care hospital in Switzerland.

PARTICIPANTS

Patients enrolled in the University Hospital Zurich's OPAT programme between October 2020 and September 2022. They were interviewed predischarge (interview 1) and 7-14 days postdischarge (interview 2) using a shortened, four-domain version of the validated SF-36) questionnaire, complemented by four additional questions gauging patient satisfaction.

CO-PRIMARY OUTCOMES

The primary outcomes were the scores in four domains of the SF-36 questionnaire.

RESULTS

33 patients participated in the study. Univariate analysis revealed substantial improvement in three of the four SF-36 domains. Specifically, participants reported improvements in the mean SF-36 score (95% CI) from interviews 1 to 2 for 'emotional role' (24.2 (5.0-43.5)), 'social functioning' (22.0 (95%CI 10.8 to 33.2)) and 'emotional well-being' (11.9 (95%CI 5.6 to 18.2)). Furthermore, 97% of patients would recommend OPAT to others.

CONCLUSION

Patients experienced significant improvements in Health-Related Quality of Life (HRQoL) while enrolled in OPAT and the programme yields high patient satisfaction. Hospitals considering new OPAT programmes should include both patient satisfaction and HRQoL impact in their argument repertoire for the introduction of OPAT.

Outpatient parenteral antibiotic therapy (OPAT) through elastomeric continuous infusion pumps in a real-life observational study: Characteristics, safety, and efficacy analysis

INTRODUCTION

This study aimed to present real-life data on the use, efficacy, and safety of administering antibiotic therapy through portable elastomeric pumps (pEP) in the outpatient setting.

METHODS

This retrospective observational cohort study was conducted from January 2020 to May 2023 in a large academic hospital in Rome, Italy. All patients receiving antibiotic therapy via pEP were included up to a follow-up period of 90 days after the end of antibiotic therapy. The primary outcome was the treatment response. Secondary endpoints were adverse events attributable to the drug administered, the vascular catheter, or the infection itself.

RESULTS

Of the 490 patients referred to our outpatient parenteral antibiotic therapy (OPAT) unit, 94 (19.2%) received antibiotic therapy via pEP and were included in the final analysis. The most frequently treated infections were those involving bone and prosthetics, including spondylodiscitis (n=27; 28.8%). Most infections were due to Pseudomonas aeruginosa (n=55; 48.3%). Cefepime (n=32; 34.0%), piperacillin/tazobactam (n=29; 30.9%), ceftolozane/tazobactam (n=7; 7.5%), and oxacillin (n=7; 7.5%) were the most frequently administered antibiotics. The infection cure rate reached 88.3% (n=83). 12 patients (12.8%) reported adverse events, of which half (6.4%) were drug-related and half (6.4%) were line-related.

CONCLUSIONS

OPAT through portable elastomeric infusion pumps proved to be safe and effective. It also contributed to the reduction of healthcare costs, fully respecting the principles of personalized medicine. This strategy has emerged as a promising tool for antibiotic stewardship and infection control.

A review of antimicrobial stability testing guidance for outpatient parenteral antimicrobial therapy programmes: is it time for global harmonization of testing frameworks?

Antimicrobial stability is an important consideration for treatment planning and service delivery in outpatient parenteral antimicrobial therapy (OPAT) programmes. Regulation of stability assessment varies by region, and conflicting guidance and standards exist. This leads to disparity of equity in access and limits availability of certain antimicrobials for managing infections in the outpatient setting. This review discusses the degree to which the international regulatory bodies have reached consensus on the regulation of antimicrobial stability testing, specifically for OPAT, and describes the variation in antimicrobial recommendations across regulatory bodies. The three major findings in this review are (i) variation in antimicrobial stability testing guidance, particularly in relation to temperature; (ii) lack of regulatory guidance, specifically in that some regions did not have OPAT guidelines; and (iii) only the UK's NHS has provided non-regulatory OPAT-specific advice on antimicrobial stability testing. In conclusion, harmonization of antimicrobial stability testing to form a global OPAT-specific regulatory framework, particularly considering 'areas of variation' amongst current guidance, is required. We call for the development of a global OPAT antimicrobial stability testing framework with consensus from accepted antimicrobial stability criteria, expert opinion and pharmacopoeial best practice.

Enhancing Stability and Investigating Target Attainment of Benzylpenicillin in Outpatient Parenteral Antimicrobial Therapy: Insights from In Vitro and In Vivo Evaluations

Background/Objective: Narrow-spectrum beta-lactam antibiotics such as benzylpenicillin and flucloxacillin are increasingly used in outpatient parenteral antimicrobial therapy (OPAT) programs to mitigate the adverse effects associated with broad-spectrum antibiotics. These beta-lactams require continuous administration via portable infusion devices during OPAT. However, the use of benzylpenicillin in OPAT requires special consideration because of its limited stability at elevated temperatures. Methods: We tested the benzylpenicillin stability, pH, and degradation of products in elastomeric pumps at different concentrations in saline and in buffered solution containing sodium citrate during a prolonged storage and at high temperatures (seven days at 2-8 °C followed by 24 h at 37 °C). Additionally, drug concentrations during intermittent bolus infusion and during OPAT were determined in five patients. The concentrations and degradation products of benzylpenicillin were measured using liquid chromatography mass spectrometry (LC-MS/MS). Results: Unbuffered benzylpenicillin solutions that were already degraded during refrigerator storage and analyte concentration were not measurable after 8 days. The stability of the buffered solutions was acceptable at all three of the tested concentrations (97.6 ± 1.3%, 96.3 ± 0.8%, and 94.9 ± 1.1% for 10 Mio IU, 20 Mio IU, and 40 Mio IU of benzylpenicillin). The stability was influenced by benzylpenicillin concentration, and several breakdown products were identified. Benzylpenicillin concentrations were measured in five patients during OPAT and ranged from 7.2 to 60 mg/L. Conclusions: Benzylpenicillin buffered with sodium citrate is a safe and convenient option for use in continuous infusions during OPAT and should be favored over broad-spectrum antibiotics. Therapeutic drug monitoring data indicate sufficient to high plasma levels when patients received benzylpenicillin as continuous infusions.

Cost comparison analysis of continuous versus intermittent antimicrobial therapy infusions in inpatient and outpatient care: real-world data from Finland

OBJECTIVE

This study compared the costs and nursing time associated with the delivery of continuous infusion of antibiotics via elastomeric infusion pumps (EIP) versus conventional intermittent infusion (CII) across different care pathways.

DESIGN

Retrospective real-world data informed a cost comparison analysis that compared costs and nursing hours between infusion of antibiotics via EIP versus CII across eight care pathways in inpatient or outpatient care during infection episodes. Real-world data were obtained from patients treated within a year with parenteral antimicrobial therapy in Päijät-Häme Region, Finland.

SETTING

Inpatient care with hospital admission and outpatient care at hospital at home in Päijät-Häme Region in Finland.

PARTICIPANTS

3778 patients with a total of 4214 infection episodes treated with intravenous antimicrobial therapy.

INTERVENTIONS

Eight treatment strategies with various combinations of EIP and CII administered in inpatient or outpatient care.

PRIMARY AND SECONDARY OUTCOME MEASURES

Direct costs and nursing time.

RESULTS

Skin and soft tissue infections accounted for the highest number of episodes treated with EIP overall (30.8%; 74 out of 240 episodes) and in outpatient care specifically (53.3%; 128 out of 240 episodes). Compared with inpatient care costs with CII (€4590 per episode), treating skin and soft tissue infections in outpatient care with EIP or CII incurred only 24% (€1104) and 35% (€1620) of the costs, respectively. Across all treatment strategies and infections studied, the use of EIP consistently required less nursing time. The highest nursing time in the outpatient care was observed in sepsis episodes treated with CII (37 hours with CII vs 7 hours with EIP per episode).

CONCLUSION

Delivery of antimicrobial therapy using continuous infusions with EIP instead of CII can significantly decrease the nursing time and cost in both inpatient and outpatient care. For skin and soft tissue infections and sepsis, the utilisation of EIP is a cost-saving option in outpatient care compared with the use of CII.

Current practices and challenges of outpatient parenteral antimicrobial therapy: a narrative review

Extended hospitalization for infection management increases inpatient care costs and the risk of healthcare-associated adverse events, including infections. The growing global demand for healthcare, the diminishing availability of hospital beds and an increasing patient preference for care within their own home have been the primary drivers of the expansion of hospital-in-the-home programmes. Such programmes include the use of IV antimicrobials in outpatient settings, known as outpatient parenteral antimicrobial therapy (OPAT). However, OPAT practices vary globally. This review article aims to describe the current OPAT practices and challenges worldwide. OPAT practice begins with patient evaluation and selection using eligibility criteria, which requires collaboration between the interdisciplinary OPAT team, patients and caregivers. Depending on care requirements, eligible patients may be enrolled to various models of care, receiving medication by healthcare professionals at outpatient infusion centres, hospital clinics, home visits or through self-administration. OPAT can be used for the management of many infections where an effective oral treatment option is lacking. Various classes of parenteral antimicrobials, including β-lactams, aminoglycosides, glycopeptides, fluoroquinolones and antifungals such as echinocandins, are used globally in OPAT practice. Despite its benefits, OPAT has numerous challenges, including complications from medication administration devices, antimicrobial side effects, monitoring requirements, antimicrobial instability, patient non-adherence, patient OPAT rejection, and challenges related to OPAT team structure and administration, all of which impact its outcome. A negative outcome could include unplanned hospital readmission. Future research should focus on mitigating these challenges to enable optimization of the OPAT service and thereby maximize the documented benefits for the healthcare system, patients and healthcare providers.

Improving antimicrobial treatment in terms of antimicrobial stewardship and health costs by an OPAT service

PURPOSE

Outpatient parenteral antimicrobial therapy (OPAT) is a standard for antimicrobial therapy internationally. With this prospective cohort study, we aimed to assess the impact of an OPAT service as part of antimicrobial stewardship (AMS) and evaluate the safety and efficiency of the program while illuminating the financial benefit for the hospital.

METHODS

Socio-demographic data, treatment regimen and outcomes were prospectively recorded for all patients assigned to the program of the OPAT unit of the University Hospital of Zurich between November 2018 and September 2022.

RESULTS

In total, we recorded 303 OPAT assignments of which 260 resulted in effective OPAT episodes. The 260 OPAT episodes were further optimized toward the choice of antimicrobial agent (n = 18) and length of therapy (n = 6). Moreover, OPAT resulted in alteration of patient assessment and care led by AMS strategies in 247 of 260 episodes (95%). While the bed days saved per year increased consistently with time, a total of 3934 in-hospital treatment days were saved amounting to a cost saving of 9,835,000 CHF over 47 months. Adverse events were recorded in 46 cases whilst only two of these have been the reason for readmission during OPAT treatment. Clinical cure was noted in 77% (199/260) and was negatively associated with Charlson Comorbidity Index (CCI; OR per 1 unit higher 0.85 (95% CI 0.78-0.93)).

CONCLUSION

This study demonstrates the impact of an OPAT service in the framework of AMS as well as its benefits for the hospital whilst preserving safety and efficacy for the patient's parenteral antimicrobial treatment.

Effectiveness and safety of a disposable elastomeric continuous infusion pump for outpatient parenteral antimicrobial therapy (OPAT) in a UK setting

We evaluated the effectiveness and safety of continuous antimicrobial infusion using a disposable elastomeric device in an outpatient parenteral antimicrobial therapy (OPAT) setting. We conducted a retrospective analysis of all patients who received either flucloxacillin (n = 131 episodes) or piperacillin/tazobactam (n = 301 episodes) as continuous infusion via elastomeric devices over 5 years (January 2018-December 2022) at a tertiary referral hospital in Derbyshire, UK. Overall, 81 adverse events were recorded in 77 (18%; 77/432) patient-episodes. Most adverse events were vascular access-related (59%; 4.6 events per 1000 OPAT-days), including one line-related infection (0.2%; 0.1 events per 1000 OPAT-days). 165 (38%) patient-episodes experienced at least one incident of incomplete infusion. Successful outcome (cure or improvement) occurred in 364 (84%) episodes. Our findings suggest that elastomeric infusion pumps are safe and effective for administering selected antimicrobial agents in OPAT. However, close monitoring of patients and the device are essential to ensure optimal delivery of prescribed therapy.

Clinical Effectiveness of Continuous Infusion Flucloxacillin in the Outpatient Parenteral Antimicrobial Therapy (OPAT) Setting in a UK Hospital: A Service Evaluation

The availability of stability data for the use of continuous intravenous flucloxacillin in an elastomeric device has enabled the treatment of serious Methicillin Sensitive Staphylococcus aureus (MSSA) in the outpatient parenteral antimicrobial therapy (OPAT) setting. This service review aimed to evaluate current standard of care to establish the clinical effectiveness and complication rates associated with its use since its introduction at our institution. A retrospective review of clinical outcomes and adverse events/complications, was undertaken for all patients who received continuous infusion flucloxacillin for complicated MSSA infection between January 2019 and July 2022 via our OPAT service. Thirty-nine patients were included. An OPAT treatment outcome of 'Treatment aim attained uncomplicated' was achieved in 29/39 (74%) patients. Two patients had an OPAT treatment outcome of treatment aim not attained, both of which required unexpected hospital re-admission. An adverse event/complication occurred in 8 patients. There were two relapses in the 12-month follow-up period. Our review supports the assertion that continuous infusion flucloxacillin is clinically effective and well tolerated for the treatment of complicated MSSA infection in the OPAT setting.

Feasibility of individualised patient modelling for continuous vancomycin infusions in outpatient antimicrobial therapy, a retrospective study

BACKGROUND

The area under the curve (AUC) to minimum inhibitory concentration (MIC) ratio is proposed as a therapeutic drug-monitoring parameter for dosing vancomycin continuous infusion in methicillin-resistant Staphylococcus aureus (MRSA) infection. Individualised pharmacokinetic-pharmacodynamic (PK/PD) calculation of AUC24 may better represent therapeutic dosing than current Therapeutic Drug Monitoring (TDM) practices, targeting a Steady State Concentration of 15-25 mg/L.

AIM

To compare real world TDM practice to theoretical, individualised, PK/PD target parameters utilising Bayesian predictions to steady state concentrations (Css) for outpatients on continuous vancomycin infusions.

METHOD

A retrospective single centre study was conducted at a tertiary hospital on adult patients, enrolled in an outpatient parenteral antimicrobial therapy (OPAT) program, receiving vancomycin infusions for MRSA infection. Retrospective Bayesian dosing was modelled to target PK/PD parameters and compared to real world data.

RESULTS

Fifteen patients were evaluated with 53% (8/15) achieved target CSS during hospitalisation, and 83% (13/15) as outpatient. Median Bayesian AUC/MIC was 613 mg.h/L with CSS 25 mg/L. Patients suffering an Acute Kidney Injury (33%) had higher AUC0-24/MIC values. Retrospective Bayesian modelling demonstrated on median 250 mg/24 h lower doses than that administered was required (R2 = 0.81) which achieved AUC24/MIC median 444.8 (range 405-460) mg.h/L and CSS 18.8 (range 16.8-20.4) mg/L.

CONCLUSION

Bayesian modelling could assist in obtaining more timely target parameters at lower doses for patients receiving continuous vancomycin infusion as part of an OPAT program, which may beget fewer adverse effects. Utilisation of personalised predictive modelling may optimise vancomycin prescribing, achieving earlier target concentrations as compared to empiric dosing regimens.

Early switch from intravenous to oral antibiotic treatment in bone and joint infections

OBJECTIVES

The timing of the switch from intravenous (i.v.) to oral antibiotic therapy for orthopaedic bone and joint infections (BJIs) is debated. In this narrative article, we discuss the evidence for and against an early switch in BJIs.

DATA SOURCES

We performed a PubMed and internet search investigating the association between the duration of i.v. treatment for BJI and remission of infection among adult orthopaedic patients.

CONTENT

Among eight randomized controlled trials and multiple retrospective studies, we failed to find any minimal duration of postsurgical i.v. therapy associated with clinical outcomes. We did not find scientific data to support the prolonged use of i.v. therapy or to inform a minimal duration of i.v.

THERAPY

Growing evidence supports the safety of an early switch to oral medications once the patient is clinically stable.

IMPLICATIONS

After surgery for BJI, a switch to oral antibiotics within a few days is reasonable in most cases. We recommend making the decision on the time point based on clinical criteria and in an interdisciplinary team at the bedside.

Feasibility, Effectiveness and Safety of Elastomeric Pumps for Delivery of Antibiotics to Adult Hospital Inpatients-A Systematic Review

Elastomeric infusion pumps (EMPs) have been implemented in many fields, including analgesia, chemotherapy and cardiology. Their application in antimicrobials is mainly limited to the outpatient setting, but with a need to optimise inpatient antimicrobial treatment, the use of EMPs presents a potential option. This review aimed to identify if the use of EMPs within an inpatient setting is feasible, effective and safe for antimicrobial use. Criteria for inclusion were human studies that involved the treatment of an infection with intravenous antimicrobial agents via an EMP. A search strategy was developed covering both the indexed and grey literature, with all study designs included. The review found 1 eligible study enrolling 6 patients. There was strong patient preference for EMPs (6/6), and daily tasks were easily completed whilst attached to the EMP. Nurses (5/5) also preffered the pumps, and the majority reported them as easy to use. The review has identified the need for further research in the area. Evidence for the use of EMPs to administer antibiotics in the inpatient setting is scarce, and more work is needed to understand the advantages to patients, to healthcare workers and from an antimicrobial stewardship perspective. Potential disadvantages that may put patients at risk also need investigating.

Elastomeric, fillable infusion pumps: an overview for clinical practice

Due to advances in elastomeric pump technology, there are now devices available that can be filled with intravenous (IV) therapy at the bed or chair side. These devices are safe, reliable and enable the patient to be mobile when having their infusion. The Surefuser™+ elastomeric infusion pump is available in multiple configurations and allows patients to remain independent and receive IV therapy infusions in their own homes. The pump can also be used in the acute healthcare setting where traditional electronic infusion pumps may not be available. This article provides an overview of the Surefuser+ elastomeric infusion pump, its features and mode of action and how it can be used in clinical practice.

International consensus recommendations for the use of prolonged-infusion beta-lactam antibiotics: Endorsed by the American College of Clinical Pharmacy, British Society for Antimicrobial Chemotherapy, Cystic Fibrosis Foundation, European Society of Clinical Microbiology and Infectious Diseases, Infectious Diseases Society of America, Society of Critical Care Medicine, and Society of Infectious Diseases Pharmacists

Intravenous β-lactam antibiotics remain a cornerstone in the management of bacterial infections due to their broad spectrum of activity and excellent tolerability. β-lactams are well established to display time-dependent bactericidal activity, where reductions in bacterial burden are directly associated with the time that free drug concentrations remain above the minimum inhibitory concentration (MIC) of the pathogen during the dosing interval. In an effort to take advantage of these bactericidal characteristics, prolonged (extended and continuous) infusions (PIs) can be applied during the administration of intravenous β-lactams to increase time above the MIC. PI dosing regimens have been implemented worldwide, but implementation is inconsistent. We report consensus therapeutic recommendations for the use of PI β-lactams developed by an expert international panel with representation from clinical pharmacy and medicine. This consensus guideline provides recommendations regarding pharmacokinetic and pharmacodynamic targets, therapeutic drug-monitoring considerations, and the use of PI β-lactam therapy in the following patient populations: severely ill and nonseverely ill adult patients, pediatric patients, and obese patients. These recommendations provide the first consensus guidance for the use of β-lactam therapy administered as PIs and have been reviewed and endorsed by the American College of Clinical Pharmacy (ACCP), the British Society for Antimicrobial Chemotherapy (BSAC), the Cystic Fibrosis Foundation (CFF), the European Society of Clinical Microbiology and Infectious Diseases (ESCMID), the Infectious Diseases Society of America (IDSA), the Society of Critical Care Medicine (SCCM), and the Society of Infectious Diseases Pharmacists (SIDP).

Outpatient parenteral antimicrobial therapy with continuous infusion of meropenem: A retrospective analysis of three years of clinical experience

INTRODUCTION

Data regarding outpatient parenteral antimicrobial therapy (OPAT) with continuous infusion of meropenem (CIM) remain scarce and controversial. We aimed to analyze its outcomes.

METHODS

We conducted a retrospective analysis of a cohort of patients who received OPAT with CIM during a three-year period at a single center in northwest Spain. Demographics, clinical data and OPAT outcomes were recorded.

RESULTS

Since January 2017-December 2019, 34 patients received 35 OPAT episodes with CIM. The median age was 75 years, and 18 (51.4%) had a Charlson comorbidity index>2. Twelve (34.3%) had respiratory infection, 11 (31.4%) urinary tract infection, and 12 (34.3%) other infections. Twenty-one (60%) received a dose of 6g/day, and 27 (77.1%) received combined antibiotic therapy. The duration of OPAT with CIM was 10 median days. Pseudomonas aeruginosa was the most frequently (34.3%) isolated microorganism and 10 (28.6%) infections were polymicrobial. During OPAT and hospital at home unit admission, 4 (11.4%) patients had any adverse reaction that required CIM withdrawal, 2 (5.7%) were readmitted, and 3 (8.8%) died (2 infection-related deaths). After 30 days from discharge 6 (18.8%) of 32 not-censored patients had unplanned readmissions (2 infection-related), 6 (18.8%) developed recurrence (3 relapses, 3 reinfections) and 1 (3.1%) died (none-infection-related death). Twenty-three (71.9%) of these 32 patients did not experience unplanned readmission, recurrence or death.

CONCLUSION

CIM can be an option to be administrated in OPAT programs in selected patients. Further studies are warranted to increase evidence regarding its use, and to externally validate our findings.

Continuous infusion of beta-lactam antibiotics: narrative review of systematic reviews, and implications for outpatient parenteral antibiotic therapy

INTRODUCTION

Continuous infusion (CI) of beta-lactam antibiotics may be of benefit in some patients, particularly those with severe infections. However, most studies have been small and conflicting results have been reported. The best available evidence on clinical outcomes of beta-lactam CI comes from systematic reviews/meta-analyses that integrate the available data.

AREAS COVERED

A search of PubMed from inception to the end of February 2022 for systematic reviews of clinical outcomes with beta-lactam CI for any indication identified 12 reviews, all of which focused on hospitalized patients, most of whom were critically ill. A narrative overview of these systematic reviews/meta-analyses is provided. No systematic reviews evaluating the use of beta-lactam CI for outpatient parenteral antibiotic therapy (OPAT) were identified, as few studies have focused on this area. Relevant data are summarized, and consideration is given to issues that need to be addressed when using beta-lactam CI in the setting of OPAT.

EXPERT OPINION

Evidence from systematic reviews supports a role for beta-lactam CI in the treatment of hospitalized patients with severe/life-threatening infections. Beta-lactam CI can play a role in patients receiving OPAT for severe chronic/difficult-to-treat infections, but additional data are needed to clarify its optimal use.

A review of evidence, antimicrobial stability, and feasibility considerations for OPAT continuous infusion

Outpatient parenteral antimicrobial therapy (OPAT) has been widely used in clinical practice for many decades because of its associated cost savings, reductions in inpatient hospital days, and decreases in hospital-associated infections. Despite this long history, evolving practice patterns and new drug delivery devices continue to present challenges as well as opportunities for clinicians when designing appropriate outpatient antimicrobial regimens. One such change is the increasing use of extended and continuous infusion (CI) of antimicrobials to optimize the achievement of pharmacokinetic and pharmacodynamic targets. Elastomeric devices are also becoming increasingly popular in OPAT, including for the delivery of CI. In this article, we review the clinical evidence for CI in OPAT, as well as practical considerations of patient preferences, cost, and antimicrobial stability.

Successful Integration of Clinical Pharmacists in an OPAT Program: A Real-Life Multidisciplinary Circuit

Outpatient parenteral antimicrobial therapy (OPAT) programs encompass a range of healthcare processes aiming to treat infections at home, with the preferential use of the intravenous route. Although several barriers arise during the implementation of OPAT circuits, recent cumulative data have supported the effectiveness of these programs, demonstrating their application in a safe and cost-effective manner. Given that OPAT is evolving towards treating patients with higher complexity, a multidisciplinary team including physicians, pharmacists, and nursing staff should lead the program. The professionals involved require previous experience in infectious diseases treatment as well as in outpatient healthcare and self-administration. As we describe here, clinical pharmacists exert a key role in OPAT multidisciplinary teams. Their intervention is essential to optimize antimicrobial prescriptions through their participation in stewardship programs as well as to closely follow patients from a pharmacotherapeutic perspective. Moreover, pharmacists provide specialized counseling on antimicrobial treatment technical compounding. In fact, OPAT elaboration in sterile environments and pharmacy department clean rooms increases OPAT stability and safety, enhancing the quality of the program. In summary, building multidisciplinary teams with the involvement of clinical pharmacists improves the management of home-treated infections, promoting a safe self-administration and increasing OPAT patients' quality of life.

Clinical Efficacy and Safety of Vancomycin Continuous Infusion in Patients Treated at Home in an Outpatient Parenteral Antimicrobial Therapy Program

Vancomycin is commonly used in outpatient parenteral antimicrobial therapy (OPAT) of Gram-positive infections. Therapeutic drug monitoring and adverse event monitoring pose a challenge. Outcome data of vancomycin in OPAT (vOPAT) are limited. The study aim was to report the safety and efficacy of a structured vOPAT program implemented in the University Hospitals Leuven. The program provides continuous elastomeric infusion of vancomycin at home with biweekly follow-up at the outpatient clinic. Demographics, clinical, biochemical and treatment parameters, target attainment parameters and clinical outcomes were recorded. An e-survey was conducted to assess patient satisfaction. Thirty-five vOPAT episodes in 32 patients were included. During 206 follow-up consultations, 203 plasma concentration measurements were registered with a median vancomycin plasma concentration of 22.5 mg/L (range 6.6–32.0). The majority of concentrations (68.5%) were within the therapeutic range (20.0–25.0 mg/L). Adverse event rates, including drug- (5.7%) and catheter-related (5.7%) events, were low. For 32 vOPAT episodes, a clinical cure rate of 100% was observed. All patients who completed the e-survey were satisfied with their vOPAT course. These findings show that a structured vOPAT program with rigorous follow-up provides safe and effective ambulatory treatment of patients with vancomycin in continuous infusion.

Stability Studies of 16 Antibiotics for Continuous Infusion in Intensive Care Units and for Performing Outpatient Parenteral Antimicrobial Therapy

The use of continuous infusion to improve the therapeutic efficacy of time-dependent antibiotics has been demonstrated. There is still a lack of data to safely perform these continuous infusions. The objectives in this study were to evaluate the stability by using stability-indicating methods (High-Performance Liquid Chromatography) of 16 antibiotics in concentrated solutions, especially for administration in intensive care units and solutions in elastomeric diffusers at 37 °C for outpatient parenteral antimicrobial therapy. The solutions were considered stable if the percentage of the drug was ≥90%, and the colour and clearness remained unchanged. In syringes, the stability data vary from 4 to 8 h (h) for meropenem in Dextrose 5% (D5W) and Normal Saline (NS), respectively, 6 h for cefotaxime, 12 h for cefoxitin, and 24 h for aztreonam, cefazolin, cefepime, cefiderocol, ceftazidime/avibactam, ceftolozane/tazobactam in NS and D5W, and in water for injection for cloxacillin. A stability period of 48 h has been validated for vancomycin (D5W), aztreonam, and piperacillin/tazobactam. Cefoxitin, cefazolin, cefepime, cefotaxime, cloxacillin, and piperacillin are unstable for diffuser administration. In diffusers, stability times vary from 6 h for cefiderocol, 8 h for ceftazidime, 12 h for ceftazidime/avibactam and ceftolozane/tazobactam (NS), 24 h for temocillin (NS) and piperacillin/tazobactam (D5W), up to 48 h for aztreonam and vancomycin. Solutions stored at 37 °C are less stable and allow the administration of seven antibiotics using diffusers.

Recent Updates in Antimicrobial Stewardship in Outpatient Parenteral Antimicrobial Therapy

Purpose of Review

Antimicrobial stewardship within acute care is common and has been expanding to outpatient areas. Some inpatient antimicrobial stewardship tactics apply to outpatient parenteral antimicrobial therapy (OPAT) and complex outpatient antimicrobial therapy (COpAT) management, but differences do exist.

Recent Findings

OPAT/COpAT is a growing area of practice and research with its own unique considerations for antimicrobial stewardship. Potential ideas for antimicrobial stewardship in the OPAT/COpAT setting include redesigning the regimen to COpAT instead of OPAT, ensuring the use of the shortest effective duration of antimicrobial therapy; using antimicrobials dosed less frequently, such as long-acting glycopeptides; optimizing antimicrobial susceptibility testing reporting for common OPAT/COpAT drugs; and establishing routine laboratory and safety monitoring. Future consensus is needed to determine validated OPAT program metrics and outcomes.

Summary

As more focus is placed on outpatient antimicrobial stewardship, clinicians practicing in OPAT should publish more data regarding OPAT program methods and outcomes as they relate to antimicrobial stewardship. These can involve patient clinical outcomes, OPAT readmission rates, OPAT therapy completion, and central line-related complications.

Characteristics, safety and cost-effectiveness analysis of self-administered outpatient parenteral antibiotic therapy via a disposable elastomeric continuous infusion pump at two county hospitals in Houston, Texas, United States

WHAT IS KNOWN AND OBJECTIVE

Outpatient parenteral antibiotic therapy (OPAT) is an attractive option for patients who require parenteral antimicrobials as outpatients. Few OPAT studies have assessed the impact of IV antibiotic therapy via elastomeric continuous pumps, with most having been conducted outside the United States and few in county hospitals. The OPAT program in Harris Health system, the county hospital system of Houston, Texas, United States, has implemented a disposable elastomeric continuous infusion pump (eCIP) for self-administered intravenous antibiotics (s-OPAT) since December 2018. Our goal was to describe the clinical characteristics of patients discharged with an eCIP, as well as the safety and cost-effectiveness of this pump.

METHODS

We retrospectively analysed patients discharged from Harris Health hospitals between 12/2018 and 02/2021 with s-OPAT via eCIP at home. We extracted various patient characteristics and outcomes related to OPAT.

RESULTS AND DISCUSSION

Among 481 OPAT patients during the study period, 91 patients received s-OPAT via eCIP. A total of 1925 days of s-OPAT were administered at home, with a median duration of 12 days. Eighty-three patients (93.4%) achieved a cure from infection, six patients (6.6%) had side effects, and nine patients (9.9%) experienced 30-day hospital readmission. Twenty-two patients (24.2%) presented to the ED during s-OPAT, with 13 patients (14.3%) presenting with PICC line concerns. We estimated that s-OPAT via eCIP saved $2,360,500 to $3,503,900 compared to inpatient-only therapy.

WHAT IS NEW AND CONCLUSION

Our study showed that patients with s-OPAT via eCIP had a high cure rate with a relatively low incidence of side effects and 30-day hospital readmission. ED visits during therapy were relatively high, which indicates the necessity of close patient monitoring via the OPAT program. eCIP appears to be a good option to facilitate an early disposition of patients in county hospitals.

Assessment of ceftolozane/tazobactam stability in elastomeric devices and suitability for continuous infusion via outpatient parenteral antimicrobial therapy

Objectives

To investigate the stability of ceftolozane/tazobactam 5 mg/mL and 20 mg/mL solutions for infusion in two elastomeric devices: FOLFusor LV10 (Baxter Healthcare) and Easypump^® II (B. Braun Medical Ltd) and determine if an extended shelf life of up to 8 days storage at 2–8°C plus 24 h ‘in use’ at 32°C was achievable.

Methods

Testing was as per the latest NHS Pharmaceutical Quality Assurance Committee Yellow Cover Document (YCD) requirements. A stability-indicating LC method was used for assessing the stability of solutions of ceftolozane/tazobactam at 5 mg/mL and 20 mg/mL (combined concentration of both actives) respectively, tested in two batches in triplicate (n = 3) at five timepoints according to the requirements of the YCD.

Results

Ceftolozane/tazobactam, diluted in 0.9% w/v sodium chloride at 5 mg/mL and 20 mg/mL, degraded during in-use storage at 32°C with <95% remaining after 18 h for some device/concentration combinations and all device/concentration combinations at 24 h, respectively. The data does support extended storage of up to 8 days at 2–8°C plus 12 h at 32°C ‘in-use’ when using either FOLFusor LV10 or Easypump^® II devices and is compliant with YCD.

Conclusions

Solutions of ceftolozane/tazobactam can be administered in outpatient parenteral antimicrobial therapy (OPAT) services following refrigerated storage for up to 8 days, when limited to a 12 h infusion at in-use temperature of 32°C. For UK OPAT services where twice daily dosing is feasible, our data provides another treatment option for challenging infections. In countries where a 10% loss of ceftolozane/tazobactam is acceptable, a 24 h infusion is supported by the data.

Outpatient therapy with piperacillin/tazobactam using elastomeric pumps in patients with Pseudomonas aeruginosa infection

The aim of this study was to evaluate the efficacy and safety of outpatient antimicrobial therapy with piperacillin-tazobactam in continuous infusion using elastomeric pumps and to evaluate the economic impact compared with conventional hospital treatment in patients with Pseudomonas aeruginosa (PA) infections. This is an observational study. Patients with PA infection treated with continuous piperacillin-tazobactam infusion using elastomeric pumps in our hospital between January 2015 and December 2017 were included. Primary outcomes were mortality during antibiotic treatment and mortality at 30 days. Secondary outcomes were reinfection or relapse at 30 days and clinical cure rate. The cost of each episode was compared with theoretical cost of the same treatment using conventional hospitalization. 35 patients were included. One patient (2.9%) died during the treatment. Overall 30-day mortality was 5.7%. No death was related to infection by PA. One patient (2.9%) had a reinfection at 30 days. Cure was achieved in 93% of patients at the end of treatment. There were no severe complications related to elastomeric pumps. Treatment cost with outpatient antimicrobial therapy was 67% lower than theoretical cost with conventional hospital treatment. Oupatient antimicrobial therapy with piperacillin-tazobactam in continuous infusion using elastomeric pumps in patients with PA infections is safe and effective with lower costs.

Continuous infusion of antibiotics using elastomeric pumps in the hospital at home setting

Introduction

To describe the avoided costs and to analyze the effectiveness of intravenous antibiotic treatment in continuous perfusion in patients at Hospital at Home Units (HHU) administered using elastomeric infusion pumps (EIP) prepared in a Hospital Pharmacy Service (HPS).

Materials and methods

Retrospective observational study of the number and type of EIP prepared in the HPS and of the treated patients. Study period: January 2017-December2018. Analyzed data: demographic data of patients, location of infection, responsible microorganism, medication and type of EIP, dose and duration of treatment and its effectiveness in terms of cure or non-cure or patient’s death. Economic valuation considering: costs of EIP, nursing time needed for preparation and cost of HHU care.

Results

A total of 1,688 EIP to treat 102 patients resulted in 106 episodes of outpatient treatment of parenteral antibiotic therapy (OPAT) for 1,409 days, thereby avoiding 1,409 days of hospital admission. A total of 59.8% of the patients were men and the mean age was 70.5 ± 17 years. A 31.1% and 68.9% of the cases were empirical and pathogen-directed treatments, respectively. The most used antimicrobials were piperacillin/ tazobactam (42.7%), ceftazidime (24.5%), meropenem (19.8%), ceftolozane/tazobactam (2.8%), and cloxacillin (1.9%). Mean duration of treatment was 13.29 ± 8.60 days. Location of infection: respiratory (42.5%), urinary (17.9%), skin and soft tissue (12.3%), bacteraemia (11.3%), osteomyelitis (7.5%), abdominal (3.8%) and 4.7% in other locations. The cure rate was 84%. Total avoided cost: 580,788.28€ in the 24 months studied.

Conclusion

This program represents very important economic savings for the health system, and the effectiveness of the antibiotic treatment has not been compromised.

Home intravenous antibiotherapy and the proper use of elastomeric pumps: Systematic review of the literature and proposals for improved use

Over several decades, the economic situation and consideration of patient quality of life have been responsible for increased outpatient treatment. It is in this context that outpatient antimicrobial treatment (OPAT) has rapidly developed. The availability of elastomeric infusion pumps has permitted prolonged or continuous antibiotic administration by dint of a mechanical device necessitating neither gravity nor a source of electricity. In numerous situations, its utilization optimizes administration of time-dependent antibiotics while freeing the patient from the constraints associated with infusion by gravity, volumetric pump or electrical syringe pump and, more often than not, limiting the number of nurse interventions to one or two a day. That much said, the installation of these pumps, which is not systematically justified, entails markedly increased OPAT costs and is liable to expose the patient to a risk of therapeutic failure or adverse effects due to the instability of the molecules utilized in a non-controlled environment, instability that necessitates close monitoring of their use. More precisely, a prescriber must take into consideration the stability parameters of each molecule (infusion duration, concentration following dilution, nature of the diluent and pump temperature). The objective of this work is to evaluate the different means of utilization of elastomeric infusion pumps in intravenous antibiotic administration outside of hospital. Following a review of the literature, we will present a tool for optimized antibiotic prescription, in a town setting by means of an infusion device.

Recent innovations and new applications of outpatient parenteral antimicrobial therapy

INTRODUCTION

Outpatient parenteral antimicrobial therapy (OPAT) is safe and effective for selected patients managed within an organized clinical service. Service configurations however are evolving, patient populations are changing and new evidence is emerging which challenges traditional OPAT practice.

AREAS COVERED

This review will discuss evolving OPAT service delivery from the traditional model of infusion center toward nonspecialist, community and remotely delivered OPAT and the challenges this represents. We consider new patient populations including those with incurable infection or infections at the end of life and difficult to reach populations including people who inject drugs. The evidence base that underpins the multi-disciplinary approach to OPAT delivery will be examined and particularly the role of the antimicrobial pharmacist and specialist nurse. Evidence for new treatment options which challenge established OPAT practice including complex oral antibiotic regimens, long acting parenteral agents and drug stability in continuous infusion antibiotics will be considered. Finally we emphasize the central importance of antimicrobial stewardship and good clinical governance which should underpin OPAT practice.

EXPERT OPINION

Changing patient populations, service structures and team roles coupled with a growing infection management evidence base means that OPAT services and practice must evolve. Challenging traditional practice is essential to ensure best patient outcomes and cost-efficiency.

Antimicrobial Stewardship: From Bedside to Theory. Thirteen Examples of Old and More Recent Strategies from Everyday Clinical Practice

"Antimicrobial stewardship" is a strategy that promotes the responsible use of antimicrobials. The objective of this paper is to focus on consolidated and more recent improvements in clinical strategies that should be adopted in hospitalized patients to ameliorate their infectious diseases' outcome and to reduce the antibiotic resistance risk through judicious use of antibiotics. We present 13 common clinical scenarios, the respective suggested interventions and the explanations of the supporting evidence, in order to help clinicians in their decision-making process. Strategies including the choice of antibiotic and dose optimization, antibiotic spectrum narrowing (de-escalation), shortening of duration, shift to oral route or outpatient parenteral antibiotic (including elastomeric pumps), and biomarkers are described and discussed.

Benefits of prolonged infusion of beta-lactam antibiotics in patients with sepsis: personal perspectives

INTRODUCTION

In the current era of relatively scarce antibiotic production and significant levels of antimicrobial resistance, optimization of pharmacokinetics and pharmacodynamics of antibiotic therapy is mandatory. Prolonged infusion of beta-lactam antibiotics in comparison to the intermittent infusion has the theoretical advantage of better patient outcomes. Apparently, conflicting data in the literature possibly underestimate the benefits of prolonged infusion of antibiotic treatment.

AREAS COVERED

We provide our perspective on the subject based on our experience and by critically evaluating literature data.

EXPERT OPINION COMMENTARY

In our opinion, the available data are suggestive of the beneficial role of prolonged infusion of beta-lactams in regard to piperacillin/tazobactam and carbapenems after administering a loading dose. While more data from randomized controlled trials are necessary to solidify or negate the evident benefits of prolonged infusion of the aforementioned antibiotics, clinicians should strongly consider this mode of administration of relevant antibiotics, especially in patients with severe infections.

Optimizing Antibiotic Treatment Strategies for Neonates and Children: Does Implementing Extended or Prolonged Infusion Provide any Advantage?

Optimizing the use of antibiotics has become mandatory, particularly for the pediatric population where limited options are currently available. Selecting the dosing strategy may improve overall outcomes and limit the further development of antimicrobial resistance. Time-dependent antibiotics optimize their free concentration above the minimal inhibitory concentration (MIC) when administered by continuous infusion, however evidences from literature are still insufficient to recommend its widespread adoption. The aim of this review is to assess the state-of-the-art of intermittent versus prolonged intravenous administration of antibiotics in children and neonates with bacterial infections. We identified and reviewed relevant literature by searching PubMed, from 1 January 1 2000 to 15 April 2020. We included studies comparing intermittent versus prolonged/continuous antibiotic infusion, among the pediatric population. Nine relevant articles were selected, including RCTs, prospective and retrospective studies focusing on different infusion strategies of vancomycin, piperacillin/tazobactam, ceftazidime, cefepime and meropenem in the pediatric population. Prolonged and continuous infusions of antibiotics showed a greater probability of target attainment as compared to intermittent infusion regimens, with generally good clinical outcomes and safety profiles, however its impact in terms on efficacy, feasibility and toxicity is still open, with few studies led on children and adult data not being fully extendable.

Recommendations for Systemic Antimicrobial Therapy in Fracture-Related Infection: A Consensus From an International Expert Group

Fracture-related infection (FRI) is a major complication in musculoskeletal trauma and one of the leading causes of morbidity. Standardization of general treatment strategies for FRI has been poor. One of the reasons is the heterogeneity in this patient population, including various anatomical locations, multiple fracture patterns, different degrees of soft-tissue injury, and different patient conditions. This variability makes treatment complex and hard to standardize. As these infections are biofilm-related, surgery remains the cornerstone of treatment, and this entails multiple key aspects (eg, fracture fixation, tissue sampling, debridement, and soft-tissue management). Another important aspect, which is sometimes less familiar to the orthopaedic trauma surgeon, is systemic antimicrobial therapy. The aim of this article is to summarize the available evidence and provide recommendations for systemic antimicrobial therapy with respect to FRI, based on the most recent literature combined with expert opinion. LEVEL OF EVIDENCE:: Therapeutic Level V. See Instructions for Authors for a complete description of levels of evidence.

Updated good practice recommendations for outpatient parenteral antimicrobial therapy (OPAT) in adults and children in the UK

UK good practice recommendations for outpatient parenteral antimicrobial therapy (OPAT) were published in 2012 and 2015 for adult and paediatric patients, respectively. Here we update the initial good practice recommendations in a combined document based on a further review of the OPAT literature and an extensive consultation process. As with the previous good practice recommendations, these updated recommendations are intended to provide pragmatic guidance for new and established OPAT services across a range of settings and to act as a set of quality indicators for service evaluation and quality improvement.

Outpatient parenteral antimicrobial therapy and antibiotic stewardship: opponents or teammates?

PURPOSE

This narrative review aims to describe barriers of outpatient parenteral antimicrobial therapy at home (OPAT), potentially compromising general standards of antibiotic stewardship (ABS) and facilitators of OPAT for ABS.

METHODS

After a literature review, five authors determined the barriers and facilitators to discuss in this review.

RESULTS

Sixty-six publications were included in the narrative review and seven barriers and five facilitators are discussed in this article. The impracticability of multiple daily dosing during OPAT, the impact of real-life temperature variations, deviations of the infusion rates of elastomeric devices, access to prolonged intravenous antibiotic therapy, not administering loading doses before the initiation of extended or continuous infusions and the transmural nature of care associated with OPAT, can lead to deviations of recommended treatment regimens and sub-optimal clinical and laboratory follow-up, with a risk of inferior clinical outcomes, adverse events, drug-resistance and higher costs. On the other hand, OPAT provides access to treatments with intravenous antibiotics and simultaneously avoids prolonged hospitalization.

CONCLUSION

Implementing ABS guidelines in OPAT programs, e.g., by using a multidisciplinary team approach and facility-specific protocols for OPAT with patient selection criteria and instructions for selection, storage, preparation and administration of antibiotics, can improve appropriate antibiotic use. Additionally, further research should examine the effectiveness of these interventions on outcomes of OPAT.