Although close clinician monitoring is warranted to avoid complications for this this type of treatment, it can be beneficial to patients and help reduce care costs.
Outpatient parenteral antimicrobial therapy (OPAT) has been used for patients requiring long courses of antimicrobial therapy since the 1970s.1 It was first employed for patients with cystic fibrosis with recurrent infections requiring the use of intravenous (IV) therapy, but since that time, its use has become increasingly more widespread, with more than 1 in 1000 patients receiving IV antibiotics through an OPAT program annually.2
The advantages of OPAT programs are multifold, including decreases in hospital length of stay, reductions in health care costs, and declines in nosocomial infections. Additionally, patient satisfaction may be increased when patients are able to receive IV antibiotics at home compared with other settings, likely due to a sooner return to “normalcy.”3 Unfortunately, patients receiving OPAT are at a heightened risk for complications, including line-associated deep venous thrombosis, catheter-related infection, and adverse drug reactions. Thirty-day hospital readmission rates in patients receiving OPAT courses range from 17% to 27%, highlighting the importance of close monitoring.4
To ensure appropriate transitions of care and frequent (eg, once weekly) monitoring, a structured multidisciplinary OPAT team is of critical importance. Many OPAT programs consist of a variation of infectious diseases (ID) physicians, advanced practice providers, nurses, and pharmacists, but the exact team composition usually varies by institution. Although the concept of OPAT has been around for nearly half a century, many institutions still lack the resources needed to compose a complete OPAT team, as recommended by the Infectious Diseases Society of America.5 In a 2014 survey of adult ID physicians participating in the Emerging Infections Network, more than 80% of respondents reported discharging patients on OPAT during an average month, but only 26% of respondents (118/448) reported having a dedicated OPAT team.6 A lack of dedicated personnel was listed as the most common barrier from respondents, which continues to be an issue nearly 10 years later with many newly established OPAT programs still working to demonstrate the critical importance of having a structured team.
In a study by Agnihotri et al, the University of Illinois Hospital and Health Sciences System set out to highlight the impact that a dedicated and formalized OPAT team can have on patient care. The group performed a retrospective quasi-experimental study evaluating patients who received an ID consultation and were discharged on OPAT for at least 2 days. The 2 time periods that were evaluated included a preintervention group, in which patients on IV antibiotics were managed by an individual physician (January 2012 to August 2013), and a postintervention group, in which patients were followed by a new structured OPAT program (October 2017 to January 2019) consisting of an ID physician (0.1 full-time equivalent [FTE]), a dedicated registered nurse (1.0 FTE), and an inpatient ID pharmacist for support as needed. The ID physician served as the medical director for the program and developed laboratory monitoring protocols and enhanced documentation standards. The nurse coordinator used protocols for laboratory review/actions and performed care coordination responsibilities. Rates of hospital readmission, OPAT-related complications, and clinical cure rates were compared between groups, and risk factors related to OPAT readmission were evaluated.
This study included 428 patients, 73 of whom received IV antibiotics preintervention and 355 of whom received IV antibiotics post intervention. Patient demographics in both groups were relatively well matched, with bone/joint infection being the most common antimicrobial indication and home infusion being the most frequent administration location in both groups. The preintervention group included more patients on vancomycin (53.4% pre vs 31.0% post; P < .001), whereas the postintervention group included more patients receiving b-lactams (56.2% pre vs 78.0% post; P < .001). Median outpatient treatment durations were longer in the preintervention group (30 days [IQR, 19-41] pre vs 25 days [IQR, 12-38] post; P = .068).
When evaluating patient outcomes, rates of unplanned OPAT-related hospital readmission declined after implementation of a structured OPAT program (17.8% [n = 13] pre vs 7.0% [n = 25] post). Of 38 total patients who had an OPAT-related readmission, the most common reasons were infection progression (53%), adverse drug reaction (26%), and line-associated issues (21%). Rates of clinical cure, defined as completion of IV antibiotics, increased from 69.8% preintervention to 94.9% post intervention (P < .001).7
In a multivariate analysis, factors independently associated with unplanned OPAT-related hospital readmission included receipt of vancomycin (overall response [OR], 2.448; 95% CI, 1.203-4.984; P = .014) and longer treatment duration (OR, 1.009; 95% CI, 1.002-1.019; P = .019). Enrollment in the strengthened OPAT program (OR, 0.449; 95% CI, 0.208-0.968; P = .041) and older age (OR, 0.969; 95% CI, 0.946-0.989; P = .007) were associated with decreased odds of OPAT-related hospital readmission, similarly to previous findings in the literature.7,8 Notably, the authors highlight several limitations to their study, including the inability to capture readmissions to other hospitals and the lack of available information related to outpatient ID follow-up appointments and timeliness of laboratory results, both of which could impact readmission rates.
The findings by Agnihotri et al are exciting for OPAT programs nationwide. The authors highlight the importance of having a multidisciplinary team dedicated to OPAT follow-up and the impact that it can have on patient care. By having dedicated resources and personnel closely monitoring a high-risk patient population, interventions can often be implemented before patients may progress to needing hospital admission. The financial impact of preventing readmissions is certainly significant and may be useful in highlighting the need for expansion of such services. The additional impact that is important to consider but difficult to monetize is the impact that formalized OPAT programs can have on patient satisfaction by providing a dedicated team available for questions, monitoring, and reassurance as they navigate a process that may be new and intimidating to them.
Highlighted Study Agnihotri G, Gross AE, Seok M, et al. Decreased hospital readmissions after programmatic strengthening of an outpatient parenteral antimicrobial therapy (OPAT) program. Antimicrob Steward Healthc Epidemiol. 2023;3(1):e33. doi:10.1017/ash.2022.330
1. Rucker RW, Harrison GM. Outpatient intravenous medications in the management of cystic fibrosis. Pediatrics. 1974;54(3):358-360.
2. Tice AD, Rehm SJ, Dalovisio JR, et al. Practice guidelines for outpatient parenteral antimicrobial therapy. IDSA guidelines. Clin Infect Dis. 2004;38(12):1651-1672. doi:10.1086/420939
3. Mansour O, Arbaje AI, Townsend JL. Patient experiences with outpatient parenteral antibiotic therapy: results of a patient survey comparing skilled nursing facilities and home infusion. Open Forum Infect Dis. 2019;6(12):ofz471. doi:10.1093/ofid/ofz471
4. Keller SC, Williams D, Gavgani M, et al. Rates of and risk factors for adverse drug events in outpatient parenteral antimicrobial therapy. Clin Infect Dis. 2018;66(1):11-19. doi:10.1093/cid/cix733
5. Norris AH, Shrestha NK, Allison GM, et al. 2018 Infectious Diseases Society of America clinical practice guideline for the management of outpatient parenteral antimicrobial therapy. Clin Infect Dis. 2019;68(1):e1-e35. doi:10.1093/cid/ciy745
6. Lane MA, Marschall J, Beekmann SE, et al. Outpatient parenteral antimicrobial therapy practices among adult infectious disease physicians. Infect Control Hosp Epidemiol. 2014;35(7):839-844. doi:10.1086/676859
7. Agnihotri G, Gross AE, Seok M, et al. Decreased hospital readmissions after programmatic strengthening of an outpatient parenteral antimicrobial therapy (OPAT) program. Antimicrob Steward Healthc Epidemiol. 2023;3(1):e33. doi:10.1017/ash.2022.330
8. Keller SC, Wang NY, Salinas A, Williams D, Townsend J, Cosgrove SE. Which patients discharged to home-based outpatient parenteral antimicrobial therapy are at high risk of adverse outcomes? Open Forum Infect Dis. 2020;7(6):ofaa178. doi:10.1093/ofid/ofaa178