The Penn Medicine COVID-19 Therapeutics Committee-Reflections on a Model for Rapid Evidence Review and Dynamic Practice Recommendations During a Public Health Emergency

The Penn Medicine COVID-19 Therapeutics Committee-an interspecialty, clinician-pharmacist, and specialist-front line primary care collaboration-has served as a forum for rapid evidence review and the production of dynamic practice recommendations during the 3-year coronavirus disease 2019 public health emergency. We describe the process by which the committee went about its work and how it navigated specific challenging scenarios. Our target audiences are clinicians, hospital leaders, public health officials, and researchers invested in preparedness for inevitable future threats. Our objectives are to discuss the logistics and challenges of forming an effective committee, undertaking a rapid evidence review process, aligning evidence-based guidelines with operational realities, and iteratively revising recommendations in response to changing pandemic data. We specifically discuss the arc of evidence for corticosteroids; the noble beginnings and dangerous misinformation end of hydroxychloroquine and ivermectin; monoclonal antibodies and emerging viral variants; and patient screening and safety processes for tocilizumab, baricitinib, and nirmatrelvir-ritonavir.

1292. Accessible Antibiotic Stewardship: Development of an Open-Source, Interactive Online Curriculum

Background

Significant gaps exist at all levels of medical training with regards to knowledge and confidence in antimicrobial prescribing and stewardship. Studies of antimicrobial prescribing perceptions have also noted that trainees and physicians desire further education on antibiotics and antimicrobial stewardship. Although courses in antimicrobial stewardship exist, these have generally been limited in scope and accessibility.

Methods

We first performed a needs assessment by reviewing all existing online antibiotic curricula. We then developed an open-source, comprehensive online antibiotic curriculum comprising educational modules for adult clinical learners to build expertise at their own pace, without financial burden. We based the curriculum on a previously validated framework for learning principles of antibiotics and drew on cognitive-load theory. Our intended learners were medical students, medical and surgical residents, and advanced practice provider trainees.

Results

There are 24 currently accessible online antibiotic learning materials, 4% of which are comprehensive, 25% of which include interactive content, and >40% of which include inaccuracies. We designed a curriculum to address these gaps. Our curriculum consists of 22 modules including videos lasting 8 minutes or less and accompanied by activities to apply and reinforce content. We partnered with a student in graphic design to create visually appealing and memorable animated videos. The modules reinforce the “3Ps and 3Ds”: 1) from what place is the infection coming, 2) what pathogens tend to live in the place of the infection and should be empirically covered with antibiotics, 3) are there patient-specific factors that affect antibiotic choice, and ) what are the drug, dose, and duration of antibiotic therapy.

Conclusion

To our knowledge, this would be the first open-source, comprehensive online curriculum targeting appropriate antibiotic selection using a novel framework for choosing antimicrobials: the “3Ps and 3Ds”. Our antibiotic curriculum is also novel in that we have built short, interactive learner-friendly modules that incorporate microbiology concepts as well as fundamentals of antimicrobial stewardship to facilitate antibiotic learning.

Disclosures

Kathleen Degnan, MD, Gilead: Grant/Research Support.

1759. Risk Factors for OPAT-Related Adverse Drug Events: A Case-Control Study

Background

Outpatient parenteral antimicrobial therapy (OPAT) offers numerous clinical advantages, though adverse drug events (ADEs) are a common and potentially preventable challenge that may contribute to 30-day readmissions and other negative outcomes. In January 2021, our OPAT program began documenting all significant ADEs using an electronic template. The purpose of this study was to characterize significant OPAT ADEs and to identify potential risk factors for their development.

Methods

Outpatient parenteral antimicrobial therapy (OPAT) offers numerous clinical advantages, though adverse drug events (ADEs) are a common and potentially preventable challenge that may contribute to 30-day readmissions and other negative outcomes. In January 2021, our OPAT program began documenting all significant ADEs using an electronic template. The purpose of this study was to characterize significant OPAT ADEs and to identify potential risk factors for their development.

Results

Cumulative ADE incidence was 11%, and median time-to-ADE was 13 days after discharge. During the study period, 54 ADE patients vs. 100 control patients were identified. The most common ADEs attributed to OPAT were kidney injury (50%), rash (10%), and leukopenia (9%) (Table 1). Most ADEs resulted in an OPAT regimen change (33%), dosage adjustment (29%), or early cessation of OPAT (21%) (Table 2). In the final logistic regression model, receipt of vancomycin, use of empiric therapy for culture-negative infection, and OPAT duration ≥ 28 days were associated with increased ADE risk, whereas African American race and receipt of ceftriaxone were protective (Table 3).

Conclusion

Several modifiable risk factors may increase the likelihood of an ADE during OPAT and should be carefully considered prior to hospital discharge. Based on these data, OPAT programs should consider employing vancomycin alternatives, diagnostic stewardship, and strategies to minimize duration of therapy.

Disclosures

Kathleen Degnan, MD, Gilead: Grant/Research Support.

1146. Real-World Experience Highlighting Tocilizumab Use in the Treatment of COVID-19

Background

Tocilizumab (TCZ) was approved by the Food and Drug Administration under emergency use authorization for treatment of COVID-19 in patients requiring supplemental oxygen, non-invasive or invasive mechanical ventilation, or extracorporeal membrane oxygenation. Despite multiple clinical trials, there remain unanswered questions surrounding TCZ use.

Methods

This multi-hospital retrospective cohort study included patients who received TCZ for COVID-19 between January 29^th, 2021 and June 30^th, 2021 at five University of Pennsylvania Health System (UPHS) hospitals. Patients were eligible for TCZ per UPHS criteria if they scored ≥ 5 on the World Health Organization (WHO) ordinal scale for ≤ 24 hours and experienced < 14 days of acute COVID-19 symptoms. Descriptive statistics were performed to characterize usage within the health system.

Results

This study evaluated 134 patients who received TCZ for the treatment of COVID-19. TCZ was ordered a median of 22 hours (interquartile range [IQR], 13.2 – 41.5) after hospital admission. A majority of patients (76.1%) were admitted to the intensive care unit and a small portion (12.7%) had a WHO ordinal scale that was >5 at time of TCZ order entry. All patients received concomitant dexamethasone therapy at a total prednisone equivalent of 400 mg (IQR, 335.6 – 480). Overall 33.6% of patients experienced an adverse event (ADE) within 30 days of TCZ administration (Table 1). Most common ADEs included bacterial infection (29.9%), hepatitis (6.7%), and fungal infection (3%); other etiologies of ADEs were not accounted for. All-cause mortality (Table 2) at day 30 occurred in 20.9% of patients and median time from TCZ administration to mortality was 12.5 days (IQR 5 – 18.3). Ninety-six patients in the cohort (71.6%) were discharged by day 30. Of the subgroup discharged by day 30, the majority (70.8%) were discharged to home.

Conclusion

Patients who received TCZ for severe COVID-19 experienced 20.9% mortality; mortality was higher among those with higher ordinal scale at the time of TCZ dosing. A large portion of patients (70.8%) were discharged to home within 30 days. One third of patients experienced an adverse event, primarily bacterial or fungal infection. Our experience may be useful in counseling patients about anticipated effects of TCZ.

Disclosures

George L Anesi, MD, MSCE, AHRQ, NHLBI, UpToDate: Advisor/Consultant|AHRQ, NHLBI, UpToDate: Grant/Research Support Kathleen Degnan, MD, Gilead: Grant/Research Support.

1833. Evaluating the Impact of Reported Beta-Lactam Allergies on Clinical Outcomes in Gram-Negative Bloodstream Infections: A Retrospective Cohort Study

Background

Approximately 15% of hospitalized patients are labeled as beta-lactam (BL) allergic. Despite this, it is estimated that &gt; 90% of patients do not have clinically significant hypersensitivity reactions and are BL-tolerant. The BL allergy label is associated with a host of downstream consequences, including receipt of suboptimal antibiotic therapy, healthcare-associated infections, and bacterial resistance. There are limited data investigating the impact of this allergy label on clinical outcomes in bloodstream infections caused by Gram-negative pathogens (GN-BSI).

Methods

This was a retrospective, single center, cohort study evaluating the impact of BL allergies on clinical outcomes in patients with GN-BSI from January 2017 to August 2021. Adult inpatients with index blood cultures positive for Pseudomonas species or Enterobacterales who received intravenous antibiotics with Gram-negative activity were included. The primary endpoint was time to effective therapy (defined as treatment with in vitro activity against a causative pathogen, as determined by phenotypic susceptibilities) and the key secondary endpoint was 30-day all-cause mortality.

Results

Overall, 120 patients were included, representing 30 BL-allergic (BL-A) and 90 BL-non-allergic (BL-NA) patients. Blood cultures positive for Pseudomonas species or Enterobacterales were evenly distributed (Table 1). Among Enterobacterales, Escherichia coli was implicated in 25% of cases overall. The most common source of infection was intra-abdominal infection. Across groups, median quick Pitt Bacteremia Score was 1 (IQR 0-2). Infectious Diseases was consulted in 37% of BL-A patients vs. 29% of BL-NA patients. Of BL allergies reported, 86% were classified as likely immunoglobulin E (IgE) mediated reactions. Allergy was not consulted in any of these cases. Median time to effective therapy was 162 minutes (IQR 20-824 minutes) vs. 103 minutes (IQR 27-775 minutes) in the BL-A and BL-NA groups, respectively. Thirty-day mortality occurred in 31% of BL-A and 21% of BL-NA patients.

Conclusion

Increased time to effective therapy and mortality rates were observed among patients with reported BL allergies. These findings highlight the importance of allergy clarification in antibiotic stewardship.

Disclosures

Kathleen Degnan, MD, Gilead: Grant/Research Support.

905. Impact of a Real-Time Electronic Alert on Antibiotic Treatment Duration for Pneumonia in Hospitalized Patients

Background

Limiting antibiotic prescribing to the shortest effective duration reduces antibiotic-associated adverse events and resistance. Up to two-thirds of patients receive excessive durations of therapy for pneumonia. This study evaluated the effect of a stewardship intervention to reduce excess antibiotic duration for inpatients with pneumonia.

Methods

A dashboard was developed to generate real-time alerts when inpatients at an academic medical center received antibiotics with an indication of community- or hospital-acquired pneumonia for more than 5 or 7 days, respectively. From November 2019 through April 2021, alerts were regularly reviewed by the antibiotic stewardship (AS) team and intervened upon when patients exceeded the guideline recommended duration of therapy for pneumonia without additional indications for continuing antibiotics. We compared inappropriate duration of therapy pre- and post-implementation of the dashboard by calculating the mean number of excess days of antibiotics beyond the recommended duration. Patients with SARS-CoV-2 infection and patients on hospital services that care for patients with cystic fibrosis, bronchiectasis, or immunocompromising conditions were excluded. Four other hospitals within the same health system that did not utilize the dashboard generated alerts served as a comparison group.

Results

During the intervention period, the AS team reviewed 834 patients with dashboard alerts and documented 115 interventions. For alerts reviewed without intervention, reasons for lack of intervention included active Infectious Diseases consult, additional infection diagnosis requiring a longer duration, and delayed clinical improvement. In the post-implementation period there was a mean of 1.28 excess days of antibiotics for pneumonia compared to the pre-implementation mean of 1.36 excess days. In comparison, aggregating data from the hospitals not utilizing the dashboard, there was a mean of 0.67 excess days post-intervention, compared to a mean 0.62 days pre-intervention.

Conclusion

The pneumonia dashboard is a potentially valuable stewardship tool which may reduce excess days of antibiotics for pneumonia. The dashboard’s impact may be improved by daily review and excluding patients with additional infection diagnoses.

Disclosures

Kathleen Degnan, MD, Gilead: Grant/Research Support.

932. Analysis of Seasonal Variation of Antibiotic Prescribing for Respiratory Tract Diagnoses in Primary Care Practices

Background

Seasonal fluctuations in antibiotic prescribing for respiratory tract diagnoses (RTDs) have been identified, but characteristics and appropriateness of these variations have not been well described. The objectives of this study were to describe seasonal variations for RTDs and to determine whether seasonal variation in prescribing is associated with inappropriate use.

Methods

From July 1, 2016 through June 30, 2017, antibiotic prescribing was analyzed for 31 primary care practices comparing winter (October-March) and summer (April-September) months. ICD-10 codes for RTDs were described as tier 1, 2, or 3 based on whether antibiotics are almost always, sometimes, or almost never indicated, respectively. Twenty visits from each of 60 providers were randomly selected and manually reviewed to determine a gold standard of antibiotic appropriateness in order to characterize the appropriateness of these seasonal variations. Associations between season and diagnosis tier, season and appropriateness, and individual provider seasonal changes in antibiotic prescribing and provider characteristics were determined.

Results

There was a lower proportion of visits with tier 3 diagnoses in winter months (68% v. 74%, p&lt; 0.01), but a greater proportion of tier 2 diagnoses (29% v. 23%, p&lt; 0.01). There were greater proportions of visits in which an antibiotic was prescribed for both tier 2 (80% vs 74%, p&lt; 0.01) and tier 3 diagnoses (23% v. 16%, p&lt; 0.01) in winter months. Using medical record review, inappropriate antibiotics were prescribed more frequently for RTDs in winter compared to summer months (73% v. 64%, p&lt; 0.01). Greater individual provider difference in proportion of RTD visits in which an antibiotic was prescribed from summer to winter was associated with family medicine v. internal medicine specialty (8.2% v. 5.1%, p&lt; 0.01), nonteaching v. teaching practice (8.1% v. 2.9%, p&lt; 0.01), and nonurban v. urban setting (9.1% v. 3.9%, p&lt; 0.01).

Conclusion

Although there was a greater proportion of tier 2 compared to tier 3 RTDs in winter months, winter months were associated with more inappropriate prescribing than in summer months. More investigation is needed to understand the drivers for seasonal variations in RTDs and inappropriate prescribing.

Disclosures

Kathleen Degnan, MD, Gilead: Grant/Research Support Michael Z. David, MD PhD, Contrafect: Grant/Research Support|GSK: Advisor/Consultant|Johnson and Johnson: Advisor/Consultant.

1654. Analysis of Prescribing Patterns for Respiratory Tract Illnesses Following the Conclusion of an Education and Feedback Intervention

Background

We previously conducted a study in primary care practices assessing the impact of an educational session paired with peer comparison feedback on antibiotic prescribing, demonstrating a reduction in overall prescribing for respiratory tract diseases (RTDs). However, the lasting effects of this intervention on antibiotic prescribing patterns without ongoing feedback are unknown.

Methods

To study the long-term effects of this feedback on antibiotic prescribing, we analyzed prescribing trends for 14 months after the initial study. We collected encounter-level data, including patient and provider information, ICD-10 codes, and antibiotics prescribed. RTDs were grouped into tiers based on prescribing appropriateness: tier 1 (almost always indicated), tier 2 (may be indicated), and tier 3 (rarely indicated). A χ² test was used to compare proportions of antibiotic prescribing between three time periods: pre-intervention, intervention, and post-intervention (following cessation of provider feedback). A mixed-effects multivariable logistic regression analysis was performed to assess the association between the period and antibiotic prescribing.

Results

We analyzed 260,900 encounters (127,324 pre-intervention, 58,431 during the intervention, and 75,145 post-intervention) from 28 practices, with patient, provider and practice characteristics in Table 1. Rates of antibiotic prescribing for RTD visits were higher in the post-intervention period than the intervention period (28.9% vs 23.0%, p< 0.001), but remained lower than the 35.2% pre-intervention rate (Figure 1, p< 0.001). In multivariable analyses, the odds of receiving a prescription was higher in the post-intervention compared to the intervention period for tier 2 (OR 1.19, 95% CI 1.10–1.30, p< 0.05) and tier 3 (OR 1.20, 95% CI 1.12–1.30) indications, but was still lower when compared to the pre-intervention period for each tier (OR 0.66, 95% CI 0.59–0.73 for tier 2; OR 0.68, 95% CI 0.61–0.75 for tier 3) (Table 2).

Table 1 includes patient, provider, and encounter level demographics.

Table 2 includes the results of the multivariable analysis.

Figure 1 is a graph of proportion of encounters with an antibiotic prescribed over time. The time period associated with the intervention is highlighted and graphs are separated by tier of appropriateness of antibiotic prescribing associated with the encounter.

Conclusion

The effects of this targeted educational and feedback program last beyond the intervention period, but without ongoing provider feedback there is a trend toward increased prescribing. Future studies are needed to determine optimal strategies to maintain the efficacy of this intervention.

Disclosures

Kathleen Degnan, MD, Gilead: Grant/Research Support Michael Z. David, MD PhD, Contrafect: Grant/Research Support|GSK: Advisor/Consultant|Johnson and Johnson: Advisor/Consultant.

168. Syndrome-Based Analysis of Oral Antimicrobial Stewardship Opportunities at Hospital Discharge

Background

Suboptimal oral antibiotic prescriptions (OAPs) are prevalent at discharge and contribute to treatment failure, resistance, toxicity, and excess costs. Syndrome-specific prescribing patterns have not been widely described at discharge, nor have specific reasons for excessive treatment durations (the most commonly cited prescribing error).

Methods

Retrospective cohort of patients discharged from a general medicine service at an academic hospital with ≥1 OAP for urinary tract infection (UTI), skin and soft tissue infection (SSTI), or lower respiratory tract infection (LRTI). Study period varied to include a random sample of encounters occurring after the most recent institutional guideline update for each syndrome. Exclusions: multiple infectious indications, discharge against medical advice, parenteral antibiotics at discharge, pregnancy, cystic fibrosis, and immunocompromising conditions. Discharge OAPs were assessed for suboptimal selection, dose, frequency, or duration according to institutional guidelines (with secondary adjudication).

Results

Analysis included 160 encounters: 70 UTIs, 66 SSTIs, and 24 LRTIs. Of 71 (44%) culture-positive infections, Enterobacterales (61%) and Streptococcus spp. (15%) were most often identified. In total, 180 OAPs were issued – most commonly cefpodoxime (21%), cefadroxil (18%), and doxycycline (17%). Overall, 99 (62%) encounters were associated with a suboptimal discharge OAP. Of 138 suboptimal characteristics identified, suboptimal duration was most frequent (57%), specifically excessive duration (45%). Proportion of suboptimal OAPs and their underlying reasons are analyzed by syndrome in Figures 1 and 2, respectively. Miscalculation (39%), intentional selection of guideline-discordant duration (29%), and omission of inpatient antibiotic days (19%) were the most frequent reasons for suboptimal duration (Fig. 3).

Conclusion

Suboptimal discharge OAPs were common for all studied syndromes, most notably SSTI. Excessive duration was a key driver, with reasons for inappropriate duration previously undescribed. Duration miscalculation and selection of appropriate treatment duration are key areas to focus electronic health record enhancements, provider education, and antimicrobial stewardship efforts.

Disclosures

All Authors: No reported disclosures

532. Establishing a SARS-CoV-2 Monoclonal Antibody Infusion Clinic: Early Trends in Outcomes and Disparities

Background

SARS-CoV-2 monoclonal antibodies (SMA) have demonstrated efficacy in treatment of early, mild to moderate COVID-19 in patients at high risk for progression to severe COVID-19. We created an SMA infusion clinic at a large, urban academic medical center using both internal and community-based referral mechanisms to promote the equitable distribution of treatment.

Methods

Data were analyzed from clinic referrals from December 13, 2020 through April 20, 2021. Patient demographics, census-based area deprivation index (ADI) scores (scale of 1-10, with 1 representing least socioeconomic deprivation and 10 representing most), and relevant comorbidities were collected. Outcomes included days of symptoms until referral, patient receipt of SMA therapy after referral, adverse events, and ER visits and hospitalizations within 14 days of SMA administration. Association between demographic factors and relevant outcomes were determined using chi-square or Wilcoxon rank-sum tests as appropriate.

Results

47/433 (11%) referred patients were ineligible based on inclusion and exclusion criteria. Of eligible patients, 310/386 (80%) received treatment; patients who did not receive treatment either declined (93%), could not be contacted (5%), no-showed (1%), or were admitted for hypoxia (1%). Of treated patients, only 3 (1%) had adverse reactions. Within 14 days of SMA administration, 28 (9%) patients visited the ER or were admitted for COVID-19. Black patients had a longer median duration of symptoms prior to referral compared to White patients (5 vs. 3 days, p < 0.01) (Figure 1). White patients were more likely to receive SMA after referral compared to Black patients (88% vs. 64%, p < 0.01), as were patients with ADI score 1-5 compared to those with ADI score 6-10 (88% vs. 70%, p < 0.01) (Figures 2 and 3). Black patients who received SMA had a higher rate of ER visits or admissions than White patients, although the difference was not statistically significant (14% vs. 7%, p = 0.10).

Figure 1. Bar graph displaying number of patients per race (White, Black, or Other) by duration of symptoms prior to referral.

Figure 2. Bar graph displaying number of patients who did and did not receive SMA by race

Figure 3. Bar graph displaying number of patients who did and did not receive SMA by ADI.

Conclusion

Rate of adverse reactions and COVID-related ER visits or admissions were low in patients who received SMA. Despite efforts to promote the equitable distribution of treatment through multiple referral mechanisms, racial and socioeconomic disparities still exist.

Disclosures

All Authors: No reported disclosures

82. Assessment of Clinical Outcomes and Antibiotic Prescribing Patterns Following Implementation of the GenMark ePlex® Blood Culture Identification Panel for Gram-positive Bloodstream Infections

Background

Rapid diagnostic testing (RDT) of bloodstream pathogens provides key information sooner than conventional identification and susceptibility testing. The GenMark ePlex® blood culture identification gram-positive (BCID-GP) panel is a molecular-based multiplex platform, with 20 Gram-positive target pathogens and 4 bacterial resistance genes that can be detected within 1.5 hours of blood culture positivity. Published studies have evaluated the accuracy of the ePlex® BCID-GP panel compared to traditional identification methods; however, studies evaluating the impact of this panel on clinical outcomes and prescribing patterns are lacking.

Methods

This multi-center, quasi-experimental study evaluated clinical outcomes and prescribing patterns before (December 2018 – June 2019) and after (August 2019 – January 2020) implementation of the ePlex® BCID-GP panel in June 2019. Hospitalized, adult patients with growth of Enterococcus faecalis, Enterococcus faecium, or Staphylococcus aureus from blood cultures were included. The primary endpoint was time to targeted antibiotic therapy, defined as time from positive Gram-stain to antibiotic adjustment for the infecting pathogen.

Results

A total of 200 patients, 100 in each group, were included. Time to targeted therapy was 47.9 hours in the pre-group versus 24.8 hours in the post-group (p&lt; 0.0001). Time from Gram-stain to organism identification was 23.03 hours (pre) versus 2.56 hours (post), p&lt; 0.0001. There was no statistically significant difference in time from Gram-stain to susceptibility results, hospital length of stay (LOS), or all-cause 30-day mortality.

Conclusion

Implementation of the GenMark ePlex® BCID-GP panel reduced time to targeted antibiotic therapy by nearly 24 hours. Clinical outcomes including hospital LOS and all-cause 30-day mortality did not show a statistical difference, although analysis of a larger sample size is necessary to appropriately assess these outcomes. This study represents the effect of RDT implementation alone, in the absence of stewardship intervention, on antibiotic prescribing patterns. These findings will inform the design of a dedicated RDT antimicrobial stewardship intervention at our institution, while also being generalizable to other institutions with RDT capabilities.

Disclosures

All Authors: No reported disclosures

Improving Outpatient Antibiotic Prescribing for Respiratory Tract Infections in Primary Care; a Stepped-Wedge Cluster Randomized Trial

BACKGROUND

Inappropriate antibiotic prescribing is common in primary care (PC), particularly for respiratory tract diagnoses (RTDs). However, the optimal approach for improving prescribing remains unknown.

METHODS

We conducted a stepped-wedge study in PC practices within a health system to assess the impact of a provider-targeted intervention on antibiotic prescribing for RTDs. RTDs were grouped into tiers based on appropriateness of antibiotic prescribing: tier 1 (almost always indicated), tier 2 (may be indicated), and tier 3 (rarely indicated). Providers received education on appropriate RTD prescribing followed by monthly peer comparison feedback on antibiotic prescribing for (1) all tiers and (2) tier 3 RTDs. Chi-squared testing was used to compare the proportion of visits with antibiotic prescriptions before and during the intervention. Mixed-effects multivariable logistic regression analysis was performed to assess the association between the intervention and antibiotic prescribing.

RESULTS

Across 30 PC practices and 185,755 total visits, overall antibiotic prescribing was reduced with the intervention, from 35.2% to 23.0% of visits (p<0.001). In multivariable analysis, the intervention was associated with a reduced odds of antibiotic prescription for tiers 2 (OR 0.57; 95% CI 0.52 - 0.62) and 3 (OR 0.57; 95% CI 0.53 - 0.61), but not for tier 1 (OR 0.98; 95% CI 0.83 - 1.16).

CONCLUSION

A provider-focused intervention reduced overall antibiotic prescribing for RTDs without affecting prescribing for infections that likely require antibiotics. Future research should examine the sustainability of such interventions, potential unintended adverse effects on patient health or satisfaction, and provider perceptions and acceptability.

54. Effectiveness of a Venous Catheter Stewardship Intervention Targeting Parenteral Antimicrobial Therapy at Hospital Discharge

Background

Peripherally inserted central catheters (PICCs) and midlines are often used in hospitalized patients who require outpatient parenteral antimicrobial therapy (OPAT) upon discharge. PICCs/midlines offer ease of insertion but still carry the risks of venous thrombosis, phlebitis, and catheter-associated infection. We report the results of a prospective audit and feedback (PAF) intervention targeting the placement of PICCs/midlines for OPAT at our institution.

Methods

We prospectively identified a cohort of patients identified by a real-time PICC/midline alert from 5/20/2019 through 5/29/2020 at two large academic medical centers. Alerts were generated by a third-party interface with the electronic health record and identified new line orders with an antimicrobial indication selected. Patients without infectious diseases (ID) consult underwent PAF by the antimicrobial stewardship team. Descriptive statistics were used to characterize patients, interventions, and outcomes.

Results

During the study period, 1267 PICC/midline alerts were identified. Most were excluded due to ID consult (85.4%). After exclusions, 113 alerts underwent full review. Median patient age was 64 years with female predominance (54.2%). Reviewable alerts most commonly originated from Pulmonary (36.5%) and Hospitalist (26.0%) services. The most frequent antimicrobial indications were pneumonia (37.5%) and bloodstream infection (28.1%), and the most frequently ordered antimicrobials were cefepime (27.1%) and piperacillin-tazobactam (17.7%). Median time from line order to insertion was 22 hours and from line insertion to discharge was 48 hours. Of 113 alerts reviewed by the stewardship team, 26 (23.0%) resulted in a recommendation to avoid line placement and 45 (39.8%) resulted in at least one specific stewardship recommendation (Table 1). Recommendations were fully or partially accepted in 58.3% of instances.

TABLE 1. Interventions Resulting from Prospective Venous Catheter Stewardship

Conclusion

Prospective audit of PICC/midline orders for OPAT identified a line-sparing opportunity in nearly 1 in 4 cases. Where line avoidance was not possible, other opportunities for antimicrobial optimization were common. This high-yield intervention should be considered for institutions that do not mandate infectious diseases consult for all OPAT discharges.

Disclosures

All Authors: No reported disclosures

1012. Characterization of Antibiotic Superutilizers in the Inpatient Setting

Background

Inappropriate use of antibiotics is a major public health concern that contributes to increased antibiotic resistance, adverse effects, and healthcare costs. Little is known about the highest utilizers, or superutilizers, who may be appropriate targets for antibiotic stewardship efforts. The purpose of this study was to characterize superutilizers at an academic hospital.

Methods

All adult patients who were admitted to the Hospital of the University of Pennsylvania and received at least one day of antibiotics between July 1, 2017 and June 30, 2018 were identified. All inpatient administrations for systemic antibacterial agents were identified. Antibiotics given in procedural areas and the emergency department were excluded, as were any antifungals and antivirals. Usage was reported as days of therapy (DOT). We compared the demographics and DOT among the superutilizers (defined as the top 1% of patients) to different groupings of the rest of the population.

Results

Overall, 13,559 patients (and 183,082 DOT) were included in the analysis, including 136 superutilizers. The superutilizers received 15% of the total antibacterial DOT and a median of 56 DOT during the 12-month period. (table)

Conclusion

Inpatient antibiotic use is unevenly distributed across the population. Higher meropenem and sulfamethoxazole/trimethoprim DOT suggest that treatment of multidrug-resistant organisms and opportunistic infection prophylaxis are more common in the superutilizer group. Additional study is needed to determine whether antimicrobial stewardship efforts could impact antibiotic use in the superutilizer population.

Disclosures

All authors: No reported disclosures.

124. Impact of Levofloxacin MIC on Outcomes with Levofloxacin Step-down Therapy in Enterobacteriaceae Bloodstream Infections

Background

The Clinical and Laboratory Standards Institute reduced the levofloxacin minimum inhibitory concentration (MIC) breakpoint from ≤2 to ≤0.5 mg/L for Enterobacteriaceae in 2019 guidelines. The reduction is based on Monte Carlo simulations for a levofloxacin dose of 750 mg daily. The aim of this study was to determine whether there was a difference in clinical outcomes in the treatment of Enterobacteriaceae bacteremia with levofloxacin step-down therapy retrospectively comparing patients with isolates with low levofloxacin MICs (≤0.5 mg/L) to high MICs (1–2 mg/L).

Methods

This retrospective, two-center cohort study included patients ≥18 years of age with a monomicrobial Enterobacteriaceae bacteremia with a levofloxacin MIC ≤2 mg/L from March 2017 through December 2018. Patients had to have received treatment with ≥3 days of levofloxacin step-down therapy, initial intravenous therapy with an agent active against the isolated organism, and total duration not exceeding 16 days from first negative blood culture. A subset of patients whose isolates had low levofloxacin MICs were randomly selected for comparison to all patients with high levofloxacin MICs in a 3:1 ratio. The primary outcome was a composite endpoint of recurrence and mortality within 30 days of completion of the antibiotic course. Secondary outcomes included post-culture length of stay (LOS) and 30-day readmission rate.

Results

Thirty-three patients with high MIC and 99 with low MIC were included. Urinary source was predominant and occurred in 44% of patients, and Escherichia coli was the infecting organism in 48%. Over 80% of patients experienced source resolution or control. The composite endpoint occurred in 8.1% of the low MIC group and 9.1% of the high MIC group (P = 0.856). Median LOS was 4.9 days (IQR 3.7–8.0) in the low MIC group and 4.3 days (IQR 3.2–6.8) in the high MIC group (P = 0.384), and readmission rate was 17.2% in the low MIC group and 15.2% in the high MIC group (P = 0.787).

Conclusion

There was no between-group difference in the primary outcome of recurrence and mortality, with a low overall event rate and short LOS post-culture. These results suggest that levofloxacin effectiveness may be sustained in patients with MICs of 1 or 2 despite levofloxacin not meeting susceptibility criteria by new definitions.

Disclosures

All authors: No reported disclosures.

2067. Improving Outpatient Antimicrobial Prescribing for Respiratory Tract Infections

Background

Antimicrobial stewardship often focuses on inpatients, yet inappropriate antimicrobial use is common in the outpatient setting. We performed a prospective, stepped wedge interventional study to assess the impact of an educational and feedback-based intervention on prescribing practices for respiratory tract infections (RTIs) in the adult primary care ambulatory setting.

Methods

Family and internal medicine practices were randomly placed into 6 cohorts, which received the intervention in a stepped wedge fashion at monthly intervals. The study period was July 1, 2016 to October 31, 2018, with the intervention occurring from October 1, 2017 to October 31, 2018. The intervention consisted of a 20-minute in-person educational session on appropriate antimicrobial prescribing for RTIs followed by monthly feedback to individual providers on their proportion of antibiotic prescriptions in comparison to their peers for (1) visits with a primary diagnosis of any RTI and (2) visits with a primary diagnosis of an RTI for which an antibiotic should rarely be prescribed (tier 3 diagnoses). The outcome of interest was whether an antibiotic was prescribed in RTI visits. Chi squared testing and logistic regression were used for analysis.

Results

Thirty-two practices participated, with 197,814 unique visits with a primary RTI diagnosis. Of these, 141,888 (71.7%) were physician visits and 55,926 (28.3%) were advanced practitioner visits (Figure 1). The proportion of visits with antibiotic prescriptions dropped from 37.2% to 24.0% following the intervention (P < 0.0001). Antibiotic prescriptions were significantly reduced for all primary RTI visits, OR 0.53 (95% CI 0.52 to 0.54), as well as for visits with tier 3 RTI diagnoses, OR 0.64 (95% CI 0.60 to 0.68). The proportion of visits with antibiotic prescriptions also exhibited a marked seasonal variation, another finding of the study (Figure 2).

Conclusion

An educational intervention with provider feedback successfully reduced antibiotic prescribing for RTIs in the ambulatory setting. Additional study is necessary to assess the sustainability of response over time after discontinuation of the monthly feedback.

Disclosures

All authors: No reported disclosures.

Microvascular transfer of the rectus abdominis muscle and myocutaneous flap in rats

A rat microvascular free rectus myocutaneous flap model with a superior epigastric vessel pedicle is presented. The rectus muscle has a predictable "flow-through" axial vascular system consisting of superior and inferior epigastric vessels anastomosing under the fascial sheath, and six to seven musculocutaneous perforating branches to the skin. The superior epigastric artery and vein, averaging 0.45 mm and 0.5 mm in diameter, can be used as the vascular pedicle in muscle or myocutaneous flap transplantation. Eight muscle and 15 myocutaneous flaps were transplanted to the groin. The myocutaneous flaps averaged 3.5 cm by 1.2 cm in size; the pedicle length averaged 11 mm. The 5 day survival was 100% for muscle flaps and 67% for myocutaneous flaps. The rectus myocutaneous flap is believed to be the first true myocutaneous model in the rat.