Outpatient parenteral antimicrobial therapy (OPAT) is a strategy to administer parenteral antibiotics in the outpatient setting.1 Potential OPAT benefits include decreased length of stay, reduced costs, and improved patient satisfaction.1–5 Outpatient parenteral antimicrobial therapy requires a vascular access device for antibiotic infusion, often a peripherally inserted central catheter (PICC ).6 Thus, OPAT risks include PICC -associated complications such as phlebitis, catheter-associated infections, and venous thrombosis.1,2,6–8 Prior literature suggests vascular access complication rates between 9% and 13% among patients with OPAT.6,8 Ensuring prompt PICC removal after OPAT completion can minimize these complications.2,6,8 There is ample literature demonstrating benefits of a multidisciplinary OPAT team, but there is no literature evaluating impact of a dedicated OPAT clinic on PICC removal rates. In March 2018, Grady Health System (GHS) implemented a multidisciplinary OPAT clinic dedicated to the care of patients discharged on OPAT. The goal of this study was to measure PICC removal rates before and after implementation of a dedicated multidisciplinary OPAT clinic at a safety-net hospital.
MATERIALS AND METHODS
Study Design and Setting
This study was a single-center, institutional review board approved, retrospective observational study conducted at GHS, a large urban safety-net hospital in Atlanta, GA. Patients at least 18 years of age, discharged on OPAT and followed up at GHS for OPAT management, were included. The pre-OPAT clinic group included patients referred from January 1, 2017, through March 31, 2018, and the post-OPAT clinic group included patients referred from April 1, 2018, through June 30, 2019. Patients could have more than one treatment course included during the study period and each unique OPAT course was counted individually. The primary outcome was the rate of documented PICC removal before and after implementation of a dedicated OPAT clinic. Secondary outcomes included difference in rates of emergency department (ED) visits and readmissions, frequency and reasons for ED visits, rate of pharmacist referral to the ED or for readmission, and difference in rates of OPAT follow-up visits after discharge between the pre- and post-OPAT clinic groups.
The multidisciplinary OPAT clinic implemented in March 2018 included a dedicated pharmacist, physicians, nurses, and social workers. The majority of patients seen in the OPAT clinic were uninsured or underinsured. The OPAT pharmacist assisted in coordinating patient follow-up, provided patient education, assessed for adherence and adverse effects, and performed therapeutic drug monitoring. Patients also received PICC care and underwent PICC removal in the clinic at the end of their treatment course. In our study, patients presenting to the clinic did not always see a physician, but rather a nurse and/or pharmacist for wound care or antibiotic drug monitoring. Thus, it was possible that during such appointment, the patient would be recommended to be admitted from clinic. Before the establishment of the OPAT clinic, patients following up at GHS were managed via telemedicine by GHS pharmacists who were not dedicated to the OPAT program. Peripherally inserted central catheter removal was typically performed at the patient primary care physician office or in the ED.
Study Definitions
An OPAT course was defined as the anticipated antibiotic treatment duration per the infectious diseases (ID) consult service at hospital discharge or per the outpatient ID providers in the case the OPAT course was shortened or extended based on patient disease progression. In addition, a course was considered completed at the time of the last OPAT encounter at GHS if the patient was lost to follow-up before treatment completion.
Data Analyses
Baseline characteristics were described for patients in the study population. Characteristics of OPAT treatment courses are described separately as patients may have had more than one OPAT treatment course during the study period.
Patient and OPAT characteristics were compared before and after implementation of the OPAT clinic using either a Fisher exact or χ2 test for categorical variables and using a t test for continuous variables. Monthly PICC removal rates before and after OPAT clinic implementation were compared using a t test. Monthly PICC removal rates were fitted in linear regression models separately for pre- and post-OPAT clinic groups, and the slopes of the 2 regression models were compared to assess whether the linear trends for PICC removal were significantly different between the 2 groups. Data analyses were conducted in SPSS for Windows (Version 11.0, Chicago, Ill) and R version (3.6.3). All tests were 2-sided with significance defined as P values less than 0.05.
RESULTS
Four-hundred fifty patients received at least one OPAT course for a total of 490 OPAT treatment courses. There were 244 OPAT treatment courses in the pre-OPAT clinic group and 246 in the post-OPAT clinic group. Both groups composed of predominately Black, male patients. Additional baseline patient characteristics are shown in Table 1 . Patients were most commonly being treated for osteomyelitis with a median OPAT treatment duration of 39 days in the pre-OPAT clinic group and 38 days in the post-OPAT clinic group (Table 2 ). Treatment regimens and their durations are described in the supplemental table, https://links.lww.com/IDCP/xxx . The median OPAT-treatment duration after discharge was 22 days and 26 days in the pre-OPAT clinic group and post-OPAT clinic groups, respectively. The most commonly identified organism was Staphylococcus aureus, although many treatment courses were empiric without an organism identified.
TABLE 1 -
Baseline Patient Characteristics (n = 450)
Pre-OPAT clinic (n = 230)
Post-OPAT clinic (n = 220)
P
Male, n (%)
159 (69.1)
167 (75.9)
0.108
Age, median (IQR), y
46.5 (34–56)
49 (38–57)
0.065
Black race, n (%)
169 (73.9)
162 (73.6)
0.947
Comorbidities, n (%)
 Hypertension
103 (44.8)
96 (43.6)
0.807
 Diabetes
81 (35.2)
89 (40.5)
0.252
 Chronic kidney disease
27 (11.7)
18 (8.2)
0.209
IQR included interquartile range.
TABLE 2 -
Baseline Treatment Characteristics (N = 490)
Pre-OPAT clinic (n = 244)
Post-OPAT clinic (n = 246)
P
Treatment duration of therapy in days, median (IQR)
39 (20–43)
38 (24–43)
0.59
Indication, n (%)
 Osteomyelitis
119 (48.8)
129 (52.4)
0.417
 Skin and soft tissue infection
28 (11.5)
13 (5.3)
0.013
 Bacteremia
56 (23.0)
55 (22.4)
0.875
 Joint infection
21 (8.6)
11 (4.5)
0.064
 Pyelonephritis
25 (10.2)
9 (3.7)
0.004
 Endocarditis
10 (4.1)
10 (4.1)
0.838
 CNS infection
10 (4.1)
11 (4.5)
0.677
 Other
20 (8.2)
34 (13.8)
0.061
Microorganisms, n (%)
 MSSA
62 (25.4)
68 (27.6)
0.576
 MRSA
43 (17.6)
42 (17.1)
0.889
 
Streptococcus species
27 (11.1)
48 (19.5)
0.009
 
Escherichia coli
23 (9.4)
11 (4.5)
0.031
 
Enterococcus species
15 (6.1)
16 (6.5)
0.871
 Other gram-positive organisms
28 (11.5)
10 (4.1)
0.002
 Other gram-negative organisms
58 (23.8)
42 (17.1)
0.066
 Mycobacterium
0 (0)
1 (0.4)
1.000
 
Treponema pallidum
10 (4.1)
3 (1.2)
0.053
 Anaerobic organisms
9 (3.7)
5 (2.0)
0.293
 
Candida species
0 (0)
5 (2.0)
0.061
 No organism identified
52 (21.3)
49 (19.9)
0.703
MRSA indicates methicillin-resistant Staphylococcus aureus ; MSSA, Methicillin-susceptible Staphylococcus aureus .
Documented PICC removal was evaluated for all treatment courses and PICC removal was compared between the pre-OPAT clinic and post-OPAT clinic groups. One hundred eighty treatment courses (73.8%) in the pre-OPAT clinic group and 213 treatment courses (86.6%) in the post-OPAT clinic group had documented PICC removal (P < 0.001). Rate of PICC removal by month is shown in Figure 1 . When evaluating monthly PICC removal data over time, there was no significant linear trend in the pre-OPAT clinic group (slope = 0.0065, P = 0.355), but there was an increasing trend in PICC removal rate post-OPAT clinic group (slope = 0.01, P = 0.00282). This illustrated a significant difference between the monthly rate of PICC removal between the pre- and post-OPAT clinic groups.
FIGURE 1: Peripherally inserted central catheter removal by month. One hundred eighty-three treatment courses (73.8%) in the pre-OPAT clinic group and 213 treatment courses (86.6%) in the post-OPAT clinic group had documented PICC removal (P < 0.001). There was no significant linear trend in the pre-OPAT clinic group, but there was an increasing trend in the PICC removal rate in the post-OPAT clinic group.
With respect to ED visits, there were 128 total ED visits in the pre-OPAT clinic group and 118 total ED visits in the post-OPAT clinic group (P = 0.864). There was no difference in the number of treatment courses in which the patient visited the ED, with 77 patients in each group presenting to the ED. Of the 128 ED visits in the pre-OPAT clinic group, 11 visits (8.6%) were referred by a GHS pharmacist compared with 17 of the 118 visits (14.4%) by the dedicated OPAT pharmacist in the post-OPAT clinic group (P = 0.324). Reasons for ED visits are described in Table 3 . There were significantly more patients who visited the ED for a PICC -related reason in the pre-OPAT clinic group (62 vs 44, P = 0.006). Patients in the post-OPAT clinic group were more likely to visit the ED for a reason unrelated to their OPAT treatment, PICC , or infection.
TABLE 3 -
Reasons for ED Visits (n = 246)
Pre-OPAT clinic (n = 128)
Post-OPAT clinic (n = 118)
P
Combined PICC -related reasons, n (%)
79 (62)
52 (44)
0.006
 PICC removal
1 (1)
2 (2)
0.609
 PICC occlusion
56 (44)
43 (36)
0.609
 PICC -related VTE
4 (3)
0 (0)
0.123
 Other PICC complication
18 (14)
7 (6)
0.035
Antibiotic adverse effect, n (%)
14 (11)
7 (6)
0.160
Worsening infection, n (%)
5 (4)
9 (8)
0.208
Other, n (%)
30 (23)
50 (42)
0.002
VTE indicates venous thromboembolism.
Twenty-eight patients (11.5%) in the pre-OPAT clinic group were readmitted to the hospital during their OPAT treatment course and 47 patients (19.1%) in the post-OPAT clinic group (P = 0.019). Of the 75 patients readmitted, 3 patients (10.7%) in the pre-OPAT clinic group were referred by a GHS pharmacist compared with 18 patients (38.3%) by the dedicated OPAT pharmacist in the post-OPAT clinic group. In the 30 days after completion of OPAT treatment, 42 patients (17.2%) in the pre-OPAT clinic group were admitted to the hospital and 37 (15.0%) in the post-OPAT clinic group (P = 0.259). In the pre-OPAT clinic group, 169 (69.3%) attended a follow-up visit scheduled within 7 days of discharge compared with 134 (54.5%) in the post-OPAT clinic group (P = 0.003). Overall, 200 patients (82%) in the pre-OPAT clinic group and 205 patients (83.3%) in the post-OPAT clinic group completed their treatment course (P = 0.690).
DISCUSSION
This study found a greater rate of documented PICC removal after the implementation of a dedicated OPAT clinic with a multidisciplinary team. In addition, there was an increasing trend for PICC removal during the study period after the OPAT clinic implementation. This same trend was not seen in the pre-OPAT clinic group. Although there was no difference in the number of treatment courses in which a patient visited the ED in this study, PICC -related ED visits decreased after implementation of the OPAT clinic. To our knowledge, there are no published data evaluating the impact of a multidisciplinary OPAT clinic on PICC removal rates. Our findings highlight the importance of an OPAT clinic with a dedicated multidisciplinary team to the care of patients on OPAT.
Outpatient parenteral antibiotic therapy is an attractive cost-effective option for patients to safely administer antibiotics at home that many health systems have incorporated for infections requiring prolonged parenteral antibiotics. However, OPAT risks include vascular access complications, which the literature reports are as many as 13% of patients on OPAT.6,8 Shrestha and colleagues6 evaluated vascular access-related complications among patients receiving OPAT at home and infusing antibiotics without assistance from a healthcare provider. The rate of vascular access-related complications was associated with a longer OPAT duration suggesting prompt vascular access removal (including PICC ) could play a role in minimizing complications. Patients who are not following up through end of therapy, and thus PICC removal, may not be receiving appropriate monitoring of their infection and antibiotics. In our study, having a dedicated multidisciplinary OPAT clinic improved PICC removal rate, therefore potentially preventing access-related complications.
Prior studies have evaluated frequency of ED visits in OPAT patients and found rates ranging from 2.9% to 4.6%.4,6 Our study had similar findings at a rate of approximately 3%. Unlike the patients in our study, Shah and colleagues4 specifically looked at a cohort of OPAT patients with private insurance and compared the impact of ID specialists managing a patient's OPAT as compared with other physicians. They found that ID-led OPAT had lower odds of an ED admission. Both the pre-OPAT clinic and post-OPAT clinic groups in our study were ID physician driven, and there was no difference in ED visits between groups. However, patients in the post-OPAT clinic group were more likely to visit the ED for a reason unrelated to OPAT. This furthered our suspicion that before implementation of the OPAT clinic, patients were presenting to the ED with PICC concerns or other infection-related issues, potentially due to poor access to other healthcare services as these patients are vulnerable to other, non-OPAT–related complications. These outcomes regarding ED visits for patients discharged with OPAT have not previously been studied in this unique, underserved population.
Many studies have evaluated readmission rates for patients on OPAT.9–12 Rates of readmission ranged from 16.7% to 26% within 30 days of discharge with OPAT in these studies. Similar to our study, Huck and colleagues9 specifically reported readmission rates throughout the duration of OPAT therapy. Readmission rates were reported as 21%, which is greater than readmission rates in our study of 11.5% and 19.1% in the pre- and post-OPAT clinic groups, respectively. Despite an increase in readmissions in the post-OPAT clinic group, significantly more patients were referred by the OPAT clinic pharmacist to be readmitted than in the pre-OPAT clinic group. This may stem from how closely the patients were being followed up in the post-OPAT clinic group as compared with the pre-OPAT clinic group, where problems may have still existed, but were not identified as they were not monitored as closely. It is unknown whether these patients would have otherwise presented for readmission if not recommended to by the OPAT clinic pharmacist.
Outpatient ID follow-up within 14 days of discharge has been independently associated with lower 30-day readmission.12 This emphasizes the importance of early outpatient follow-up for patients with OPAT. In our study, greater than 50% of patients attended a follow-up appointment visit within 7 days of discharge from the hospital with OPAT. It is unclear why more patients attended follow-up visits within 7 days in the pre-OPAT clinic group compared with the post-OPAT clinic group. To our knowledge, no prior studies have specifically evaluated the impact of a dedicated OPAT clinic on follow-up rates.
Although a positive impact on documented PICC removal was observed, there are notable limitations. First, this study relied on retrospective review of patients' medical charts and therefore was limited by incomplete documentation of PICC removal. Second, patients who only required short courses of parenteral antibiotics may have been dispensed their full antibiotic supply at discharge and only required follow-up for PICC removal. These patients may not have required a follow-up appointment, which was not specifically evaluated. Third, there is potential for misclassification of ED visits due to lack of evaluation for medication adverse effects or documentation of concern for a PICC -related infection. Only documentation from the pharmacist was evaluated for referral to the ED; thus, if other providers from the OPAT clinic provided this recommendation, it was not captured. Despite the previously mentioned limitations, it is unlikely that they would have changed over time and would not likely have been different between the 2 groups. Finally, the included patients were underinsured or uninsured with potentially poor access to healthcare services. It is unclear whether including underinsured or uninsured patients played a role in the outcomes seen and results may differ if this were a predominately insured patient population.
This study identified a positive impact of a dedicated OPAT clinic with a multidisciplinary OPAT team on documented PICC removals. Although there was a decrease identified in PICC -related ED visits, this was not necessarily translated to a reduction in total ED visits or readmissions during OPAT therapy. Future studies are needed with varying patient populations to understand the impact of a dedicated multidisciplinary OPAT clinic in other settings.
REFERENCES
1. 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.
CID . 2019;68(1):e1–e35.
2. Hatcher J, Costelloe C, Cele R, et al. Factors associated with successful completion of outpatient parenteral antibiotic therapy (OPAT): a 10-year review from a large West London service.
Int J Antimicrob Agents . 2019;54(2):207–214.
3. Chung EK, Beeler CB, Muloma EW, et al. Development and implementation of a pharmacist-managed outpatient parenteral antimicrobial therapy program.
Am J Health-Syst Pharm . 2016;73:e24–e33.
4. Shah PJ, Berman SJ, Graham DR, et al. Monitoring of outpatient parenteral antimicrobial therapy and implementation of clinical pharmacy services at a community hospital infusion unit.
J Pharm Pract . 2015;28(5):462–468.
5. Mitchell ED, Czoski Murray C, Meads D, et al. Clinical and cost-effectiveness, safety and acceptability of community intravenous antibiotic service models: CIVAS systematic review.
BMJ Open . 2017;7:e013560.
6. Shrestha NK, Shrestha J, Everett A, et al. Vascular access complications during outpatient parenteral antimicrobial therapy at home: a retrospective cohort study.
J Antimicrob Chemother . 2016;71:506–512.
7. Keller SC, Williams D, Gavgani M, et al. Rates of and risk factors for adverse drug events in outpatient parenteral antimicrobial therapy.
CID . 2018;66(1):11–19.
8. Keller SC, Dzintars K, Gorski LA, et al. Antimicrobial agents and catheter complications in outpatient parenteral antimicrobial therapy.
Pharmacotherapy . 2018;38(4):476–481.
9. Huck D, Ginsberg JP, Gordon SM, et al. Association of laboratory test result availability and rehospitalizations in an outpatient parenteral antimicrobial therapy programme.
CID . 2014;69(1):228–233.
10. Allison GM, Muldoon EG, Kent DM, et al. Prediction model for 3-day hospital readmissions among patients discharged receiving outpatient parenteral antibiotic therapy.
CID . 2014;58(6):812–819.
11. Bhavan KP, Brown LS, Haley RW. Self-administered outpatient antimicrobial infusion by uninsured patients discharged from a safety-net hospital: a propensity-score-balanced retrospective cohort study.
PLoS Med . 2015;12(12):e1001922.
12. Saini E, Ali M, Dur P, et al. Early infectious disease outpatient follow-up of outpatient parenteral antimicrobial therapy patients reduced 30-day readmission.
CID . 2019;69(5):865–868.