Background: External comparisons of antimicrobial use (AU) may be more informative if adjusted for encounter characteristics. Optimal methods to define input variables for encounter-level risk-adjustment models of AU are not established. Methods: This retrospective analysis of electronic health record data included 50 US hospitals in 2020-2021. We used NHSN definitions for all antibacterials days of therapy (DOT), including adult and pediatric encounters with at least 1 day present in inpatient locations. We assessed 4 methods to define input variables: 1) diagnosis-related group (DRG) categories by Yu et al., 2) adjudicated Elixhauser comorbidity categories by Goodman et al., 3) all Clinical Classification Software Refined (CCSR) diagnosis and procedure categories, and 4) adjudicated CCSR categories where codes not appropriate for AU risk-adjustment were excluded by expert consensus, requiring review of 867 codes over 4 months to attain consensus. Data were split randomly, stratified by bed size as follows: 1) training dataset including two-thirds of encounters among two-thirds of hospitals; 2) internal testing set including one-third of encounters within training hospitals, and 3) external testing set including the remaining one-third of hospitals. We used a gradient-boosted machine (GBM) tree-based model and two-staged approach to first identify encounters with zero DOT, then estimate DOT among those with >0.5 probability of receiving antibiotics. Accuracy was assessed using mean absolute error (MAE) in testing datasets. Correlation plots compared model estimates and observed DOT among testing datasets. The top 20 most influential variables were defined using modeled variable importance. Results: Our datasets included 629,445 training, 314,971 internal testing, and 419,109 external testing encounters. Demographic data included 41% male, 59% non-Hispanic White, 25% non-Hispanic Black, 9% Hispanic, and 5% pediatric encounters. DRG was missing in 29% of encounters. MAE was lower in pediatrics as compared to adults, and lowest for models incorporating CCSR inputs (Figure 1). Performance in internal and external testing was similar, though Goodman/Elixhauser variable strategies were less accurate in external testing and underestimated long DOT outliers (Figure 2). Agnostic and adjudicated CCSR model estimates were highly correlated; their influential variables lists were similar (Figure 3). Conclusion: Larger numbers of CCSR diagnosis and procedure inputs improved risk-adjustment model accuracy compared with prior strategies. Variable importance and accuracy were similar for agnostic and adjudicated approaches. However, maintaining adjudications by experts would require significant time and potentially introduce personal bias. If findings are confirmed, the need for expert adjudication of input variables should be reconsidered.

Disclosure: Elizabeth Dodds Ashley: Advisor- HealthTrackRx. David J Weber: Consultant on vaccines: Pfizer; DSMB chair: GSK; Consultant on disinfection: BD, GAMA, PDI, Germitec

The escalating threat of antimicrobial resistance (AMR) necessitates impactful, reproducible, and scalable antimicrobial stewardship strategies. This review addresses the critical need to enhance the quality of antimicrobial stewardship intervention research. We propose five considerations for authors planning and evaluating antimicrobial stewardship initiatives. Antimicrobial stewards should consider the following mnemonic ABCDE: (A) plan Ahead using implementation science; (B) Be clear and thoroughly describe the intervention by using the TidIER checklist; (C) Use a Checklist to comprehensively report study components; (D) Select a study Design carefully; and (E) Assess Effectiveness and implementation by selecting meaningful outcomes. Incorporating these recommendations will help strengthen the evidence base of antimicrobial stewardship literature and support optimal implementation of strategies to mitigate AMR.

The standardized antibiotic administration ratio (SAAR) enables comparison of antibiotic use (AU) within and between hospitals and identifies target locations and antimicrobials for stewardship interventions. Thousands of institutions have already been submitting AU to the National Healthcare Safety Network. We highlight the benefits and meaningful utilization of SAAR in conjunction with antimicrobial stewardship interventions to improve antimicrobial prescribing in the clinical setting.

Policies that promote conversion of antibiotics from intravenous to oral route administration are considered “low hanging fruit” for hospital antimicrobial stewardship programs. We developed a simple metric based on digestive days of therapy divided by total days of therapy for targeted agents and a method for hospital comparisons. External comparisons may help identify opportunities for improving prospective implementation.

We surveyed healthcare workers within the Duke Antimicrobial Stewardship Outreach Network (DASON) to describe beliefs regarding coronavirus disease 2019 (COVID-19) vaccination and their decision-making process behind vaccination recommendations. In contrast to the type of messaging that appealed most on a personal level to the healthcare workers, they preferred a more generic message emphasizing safety and efficacy when making vaccination recommendations.

Initial assessments of coronavirus disease 2019 (COVID-19) preparedness revealed resource shortages and variations in infection prevention policies across US hospitals. Our follow-up survey revealed improvement in resource availability, increase in testing capacity, and uniformity in infection prevention policies. Most importantly, the survey highlighted an increase in staffing shortages and use of travel nursing.

Background: Evidence-based hospital antimicrobial stewardship interventions, such as postprescription review with feedback, prior authorization, and handshake stewardship, involve communication between stewards and frontline prescribers. Hierarchy, asymmetric responsibility, prescribing etiquette, and autonomy can obstruct high-quality communication in stewardship. Little is known about the strategies that stewards use to overcome these barriers. The objective of this study was to identify how stewards navigate communication challenges when interacting with prescribers. Methods: We conducted semistructured interviews with antimicrobial stewards recruited from hospitals across the United States. Interviews were audio recorded, transcribed, and analyzed using a flexible coding approach and the framework method. Social identity theory and role theory were used to interpret framework matrices. Results: Interviews were conducted with 58 antimicrobial stewards (25 physicians and 33 pharmacists) from 10 hospitals (4 academic medical centers, 4 community hospitals, and 2 children’s hospitals). Respondents who felt empowered in their interactions with prescribers explicitly adopted a social identity that conceptualized stewards and prescribers as being on the “same team” with shared goals (in-group orientation). Drawing on the meaning conferred via this social role identity, respondents engaged in communication strategies to build and maintain common bonds with prescribers. These strategies included moderating language to minimize defensive recommendations when delivering stewardship recommendations, aligning the goals of stewardship with the goals of the clinical team, communicating with prescribers about things other than stewardship, compromising for the sake of future interactions, and engaging in strategic face-to-face interaction. Respondents who felt less empowered in their interactions thought of themselves as outsiders to the clinical team and experienced a heightened sense of “us versus them” mentality with the perception that stewards primarily serve a gate-keeping function (ie, outgroup orientation). These respondents expressed deference to hierarchy, a reluctance to engage in face-to-face interaction, a feeling of cynicism about the impact of stewardship, and a sense of low professional accomplishment within the role. Respondents who exhibited an in-group orientation were more likely than those who did not to describe the positive impact of stewardship mentors or colleagues on their social role identity. Conclusions: The way antimicrobial stewards perceive their role and identity within the social context of their healthcare organization influences how they approach communication with prescribers. Social role identity in stewardship is shaped by the influence of mentors and colleagues, indicating the importance of supportive relationships for the development of steward skill and confidence.

Funding: No

Disclosures: None

Background: Reflex urine cultures (RUCs) have the potential to reduce unnecessary urine cultures and antibiotic use. However, urinalysis parameters that best predict true infection are unknown. In this study, we surveyed different RUC practices in laboratories across a regional network of community hospitals. Methods: We conducted a voluntary electronic survey of infection preventionists to describe laboratory practices relating to RUCs across 51 community hospitals in the Duke Infection Control Outreach Network (DICON) between May 15, 2019, and July 3, 2019. Results: We received 51 responses (response rate, 100%). Most hospital laboratories were located in North Carolina (n = 25, 49%) and Georgia (n = 18, 35%); 28 laboratories (55%) incorporated RUCs. Surveyed laboratories accepted urine samples from any source and various collection methods (eg, indwelling catheter specimens, clean catch specimens). Moreover, 24 laboratories (86%) offered RUCs for all patients, whereas 4 laboratories (14%) restricted RUCs to specific populations (ie, outpatient, emergency room or children). We observed wide variability in the urinalysis criteria used for RUCs (Table 1); 26 unique approaches were used among 28 laboratories. Also, 24 laboratories (86%) used multiple criteria and 4 (14%) used 1 criterion. Of those that used multiple criteria, all 24 proceeded to RUC if at least 1 UA criterion was met. Furthermore, 22 laboratories (79%) incorporated the presence of nitrites as a urinalysis criterion; 21 laboratories (75%) incorporated white blood cell count (WBC) as a criterion. The most frequent WBC cutoffs were “≥5” (n = 11, 39%) and “≥10” (n = 7, 25%). In addition, 21 laboratories (75%) incorporated leukocyte esterase as a urinalysis criterion, with criteria including “positive” (n = 15, 54%), “trace” (n = 4, 14%), “moderate” (n = 1, 4%), and “large” (n = 1, 4%). Also, 17 (61%) laboratories incorporated magnitude of bacteriuria as a urinalysis criterion. The cutoff ranged from “few” (n = 8, 29%), “moderate” (n = 7, 25%), to “many” (n = 2, 7%). Another 3 (11%) laboratories incorporated other criteria: presence of blood (n = 2, 7%) and presence of fungal elements (n = 1, 4%). Only 3 (11%) laboratories utilized epithelial cells as an exclusion criterion where urinalysis would not proceed to culture if epithelial cells in urinalysis samples exceeded the designated limit, ranging from “>5” to “>15”. Conclusions: More than half of the hospitals in our community hospital network utilize RUCs, but criteria varied widely. Future epidemiological research should aim to identify ideal urinalysis parameters as well as specific patient populations that safely benefit from RUC strategies.

Funding: None

Disclosures: None

Background: Reducing inappropriate antibiotic use is critical for fighting antibiotic resistance. Quantifying the amount and diversity of antibiotic use in US hospitals is foundational to these efforts but hampered by limited national surveillance. The current study aims to address this knowledge gap by examining adult inpatient antibiotic usage, including regional, facility, and case-mix differences, across 576 hospitals and nearly 12 million encounters in 2016–2017. Methods: We conducted a retrospective cohort study of patients aged ≥18 years discharged from hospitals in the Premier Healthcare Database, a repository of nearly 1 of every 4 annual US hospitalizations, between January 1, 2016, and December 31, 2017. Detailed hospital- and patient-level data were extracted for each admission. Facilities were classified geographically by census division. Using daily antibiotic charge data, we mapped antibiotics to 18 mutually exclusive classes and to categories based upon spectrum of activity. Patient-level data were transformed into hospital case-mix variables (eg, hospital mean patient age), and relationships between antibiotic days of therapy (DOTs), and these and other facility-level variables were evaluated in negative binomial regression models. Results: The study included 11,701,326 adult admissions, totaling 64,064,632 patient days across 576 US hospitals. Overall, antibiotics were used in 65% of all hospitalizations, at a rate of 870 DOTs per 1,000 patient days. The most commonly used classes per patient days were

β-lactam/β-lactamase inhibitor combinations (206 DOTs), third- and fourth-generation cephalosporins (128 DOTs), and glycopeptides (113 DOTs) (Fig. 1). By spectrum of activity, antipseudomonal agents (245 DOTs) were the most common. Crude usage rates varied by geographic region (Fig. 2). In multivariable analyses, teaching hospitals, and/or larger bed sizes were independently associated with lower use across a range of antibiotic classes (adjusted IRR ranges, 0.90–0.94 and 0.96–0.98, respectively). Significant regional differences also persisted. Compared to the South Atlantic region (chosen as the reference category because it had the largest representation in the cohort), rates of total antibiotic use were 6%, 15%, and 18% lower on average in the Pacific, New England, and the Middle Atlantic regions, respectively. By class, carbapenems reflected the most geographic variability. Conclusions: In a large, diverse cohort of US hospitals, adult inpatients received antibiotics at a rate similar to, but higher than, previously published estimates. In adjusted models, lower antibiotic use was frequently associated with facilities likely to have robust antibiotic stewardship programs—those with teaching status and larger bed size. Further research to understand other reasons for regional differences in antibiotic use such as different rates of resistance is needed.

Funding: This work was supported by Funding: from the Agency for Healthcare Research and Quality (AHRQ) (R01-HS026205 to A.D.H.).

Disclosures: None

Infectious diseases professional societies, public health agencies, and healthcare regulatory agencies call for antibiotic stewardship programs (ASP) in many healthcare settings. However, medical legal implications of these programs remain largely uncharted territory. Although there is no legal precedent addressing issues of liability and standards of care on this subject, anticipating how the courts may assess questions of medical liability with respect to the various components of ASPs is important to define best practices in ASP operations, not only to manage the potential risk but also to improve patient care. This article seeks to address some of the common processes and interventions involved in antibiotic stewardship and the potential professional liability implications of these activities.

We analyzed antibiotic use data from 29 southeastern US hospitals over a 5-year period to determine changes in antibiotic use after the fluoroquinolone US Food and Drug Administration (FDA) advisory update in 2016. Fluoroquinolone use declined both before and after the FDA announcement, and the use of select, alternative antibiotics increased after the announcement.

Fluoroquinolones are among the 4 most commonly prescribed antibiotic classes.1,2 Postmarketing reports of serious adverse events linked to fluoroquinolones include tendonitis, neuropathy, hypoglycemia, psychiatric side effects, and possible aortic vessel rupture, leading to safety label changes in July 2008 and August 2013.3 In July 2016, the US Food and Drug Administration (FDA) strengthened the “black box” warning following an initial safety announcement in May 2016, recommending avoidance of fluoroquinolones for uncomplicated infections such as acute exacerbation of chronic bronchitis, uncomplicated urinary tract infections, and acute bacterial sinusitis.4 Concerns over safety and the association with Clostridiodes difficile infection have led inpatient antimicrobial stewardship programs (ASPs) to develop initiatives to promote avoidance of quinolones. The objective of this study was to quantify the effect of the 2016 FDA “black box” update on inpatient antibiotic use among a cohort of southeastern US hospitals.

Patient days and days present were compared to directly measured person time to quantify how choice of different denominator metrics may affect antimicrobial use rates. Overall, days present were approximately one-third higher than patient days. This difference varied among hospitals and units and was influenced by short length of stay.

Infect Control Hosp Epidemiol 2018;39:612–615