Active Surveillance and Contact Precautions for Preventing Methicillin-Resistant Staphylococcus aureus Healthcare-Associated Infections During the COVID-19 Pandemic.

BACKGROUND: Statistically significant decreases in methicillin-resistant Staphylococcus aureus (MRSA) healthcare-associated infections (HAIs) occurred in Veterans Affairs (VA) hospitals from 2007 to 2019 using a national policy of active surveillance (AS) for facility admissions and contact precautions for MRSA colonized (CPC) or infected (CPI) patients, but the impact of suspending these measures to free up laboratory resources for testing and conserve personal protective equipment for coronavirus disease 2019 (COVID-19) on MRSA HAI rates is not known. METHODS: From July 2020 to June 2022 all 123 acute care VA hospitals nationwide were given the rolling option to suspend (or re-initiate) any combination of AS, CPC, or CPI each month, and MRSA HAIs in intensive care units (ICUs) and non-ICUs were tracked. RESULTS: There were 917 591 admissions, 5 225 174 patient-days, and 568 MRSA HAIs. The MRSA HAI rate/1000 patient-days in ICUs was 0.20 (95% confidence interval [CI], .15-.26) for facilities practicing "AS + CPC + CPI" compared to 0.65 (95% CI, .41-.98; P < .001) for those not practicing any of these strategies, and in non-ICUs was 0.07 (95% CI, .05-.08) and 0.12 (95% CI, .08-.19; P = .01) for the respective policies. Accounting for monthly COVID-19 facility admissions using a negative binomial regression model did not change the relationships between facility policy and MRSA HAI rates. There was no significant difference in monthly facility urinary catheter-associated infection rates, a non-equivalent dependent variable, in the policy categories in either ICUs or non-ICUs. CONCLUSIONS: Facility removal of MRSA prevention practices was associated with higher rates of MRSA HAIs in ICUs and non-ICUs.

Optimal Urine Culture Diagnostic Stewardship Practice-Results from an Expert Modified-Delphi Procedure.

BACKGROUND: Urine cultures are nonspecific and often lead to misdiagnosis of urinary tract infection and unnecessary antibiotics. Diagnostic stewardship is a set of procedures that modifies test ordering, processing, and reporting in order to optimize diagnosis and downstream treatment. In this study, we aimed to develop expert guidance on best practices for urine culture diagnostic stewardship. METHODS: A RAND-modified Delphi approach with a multidisciplinary expert panel was used to ascertain diagnostic stewardship best practices. Clinical questions to guide recommendations were grouped into three thematic areas (ordering, processing, reporting) in practice settings of emergency department, inpatient, ambulatory, and long-term care. Fifteen experts ranked recommendations on a 9-point Likert scale. Recommendations on which the panel did not reach agreement were discussed during a virtual meeting, then a second round of ranking by email was completed. After secondary review of results and panel discussion, a series of guidance statements was developed. RESULTS: One hundred and sixty-five questions were reviewed. The panel reaching agreement on 104, leading to 18 overarching guidance statements. The following strategies were recommended to optimize ordering urine cultures: requiring documentation of symptoms, sending alerts to discourage ordering in the absence of symptoms, and cancelling repeat cultures. For urine culture processing, conditional urine cultures and urine white blood cell count as criteria were supported. For urine culture reporting, appropriate practices included nudges to discourage treatment under specific conditions and selective reporting of antibiotics to guide therapy decisions. CONCLUSIONS: These 18 guidance statements can optimize use of urine cultures for better patient outcomes.

Trends in Illness Severity, Hospitalization, and Mortality for Community-Onset Pneumonia at 118 US Veterans Affairs Medical Centers.

BACKGROUND: Deaths from pneumonia were decreasing globally prior to the COVID-19 pandemic, but it is unclear whether this was due to changes in patient populations, illness severity, diagnosis, hospitalization thresholds, or treatment. Using clinical data from the electronic health record among a national cohort of patients initially diagnosed with pneumonia, we examined temporal trends in severity of illness, hospitalization, and short- and long-term deaths. DESIGN: Retrospective cohort PARTICIPANTS: All patients >18 years presenting to emergency departments (EDs) at 118 VA Medical Centers between 1/1/2006 and 12/31/2016 with an initial clinical diagnosis of pneumonia and confirmed by chest imaging report. EXPOSURES: Year of encounter. MAIN MEASURES: Hospitalization and 30-day and 90-day mortality. Illness severity was defined as the probability of each outcome predicted by machine learning predictive models using age, sex, comorbidities, vital signs, and laboratory data from encounters during years 2006-2007, and similar models trained on encounters from years 2015 to 2016. We estimated the changes in hospitalizations and 30-day and 90-day mortality between the first and the last 2 years of the study period accounted for by illness severity using time covariate decompositions with model estimates. RESULTS: Among 196,899 encounters across the study period, hospitalization decreased from 71 to 63%, 30-day mortality 10 to 7%, 90-day mortality 16 to 12%, and 1-year mortality 29 to 24%. Comorbidity risk increased, but illness severity decreased. Decreases in illness severity accounted for 21-31% of the decrease in hospitalizations, and 45-47%, 32-24%, and 17-19% of the decrease in 30-day, 90-day, and 1-year mortality. Findings were similar among underrepresented patients and those with only hospital discharge diagnosis codes. CONCLUSIONS: Outcomes for community-onset pneumonia have improved across the VA healthcare system after accounting for illness severity, despite an increase in cases and comorbidity burden.

Epidemiology and outcomes associated with carbapenem-resistant Acinetobacter baumannii and carbapenem-resistant Pseudomonas aeruginosa: a retrospective cohort study.

BACKGROUND: Carbapenem-resistant Acinetobacter baumannii (CRAB) and carbapenem-resistant Pseudomonas aeruginosa (CRPA) are a growing threat. The objective of this study was to describe CRAB and CRPA epidemiology and identify factors associated with mortality and length of stay (LOS) post-culture. METHODS: This was a national retrospective cohort study of Veterans with CRAB or CRPA positive cultures from 2013 to 2018, conducted at Hines Veterans Affairs Hospital. Carbapenem resistance was defined as non-susceptibility to imipenem, meropenem and/or doripenem. Multivariable cluster adjusted regression models were fit to assess the association of post-culture LOS among inpatient and long-term care (LTC) and to identify factors associated with 90-day and 365-day mortality after positive CRAB and CRPA cultures. RESULTS: CRAB and CRPA were identified in 1,048 and 8,204 unique patients respectively, with 90-day mortality rates of 30.3% and 24.5% and inpatient post-LOS of 26 and 27 days. Positive blood cultures were associated with an increased odds of 90-day mortality compared to urine cultures in patients with CRAB (OR 6.98, 95% CI 3.55-13.73) and CRPA (OR 2.82, 95% CI 2.04-3.90). In patients with CRAB and CRPA blood cultures, higher Charlson score was associated with increased odds of 90-day mortality. In CRAB and CRPA, among patients from inpatient care settings, blood cultures were associated with a decreased LOS compared to urine cultures. CONCLUSIONS: Positive blood cultures and more comorbidities were associated with higher odds for mortality in patients with CRAB and CRPA. Recognizing these factors would encourage clinicians to treat these patients in a timely manner to improve outcomes of patients infected with these organisms.

Simulated Adoption of 2019 Community-Acquired Pneumonia Guidelines Across 114 Veterans Affairs Medical Centers: Estimated Impact on Culturing and Antibiotic Selection in Hospitalized Patients.

BACKGROUND: The 2019 American Thoracic Society/Infectious Diseases Society of America guidelines for community-acquired pneumonia (CAP) revised recommendations for culturing and empiric broad-spectrum antibiotics. We simulated guideline adoption in Veterans Affairs (VA) inpatients. METHODS: For all VA acute hospitalizations for CAP from 2006-2016 nationwide, we compared observed with guideline-expected proportions of hospitalizations with initial blood and respiratory cultures obtained, empiric antibiotic therapy with activity against methicillin-resistant Staphylococcus aureus (anti-MRSA) or Pseudomonas aeruginosa (antipseudomonal), empiric "overcoverage" (receipt of anti-MRSA/antipseudomonal therapy without eventual detection of MRSA/P. aeruginosa on culture), and empiric "undercoverage" (lack of anti-MRSA/antipseudomonal therapy with eventual detection on culture). RESULTS: Of 115 036 CAP hospitalizations over 11 years, 17 877 (16%) were admitted to an intensive care unit (ICU). Guideline adoption would slightly increase respiratory culture (30% to 36%) and decrease blood culture proportions (93% to 36%) in hospital wards and increase both respiratory (40% to 100%) and blood (95% to 100%) cultures in ICUs. Adoption would decrease empiric selection of anti-MRSA (ward: 27% to 1%; ICU: 61% to 8%) and antipseudomonal (ward: 25% to 1%; ICU: 54% to 9%) therapies. This would correspond to greatly decreased MRSA overcoverage (ward: 27% to 1%; ICU: 56% to 8%), slightly increased MRSA undercoverage (ward: 0.6% to 1.3%; ICU: 0.5% to 3.3%), with similar findings for P. aeruginosa. For all comparisons, P < .001. CONCLUSIONS: Adoption of the 2019 CAP guidelines in this population would substantially change culturing and empiric antibiotic selection practices, with a decrease in overcoverage and slight increase in undercoverage for MRSA and P. aeruginosa.

Decreases in Antimicrobial Use Associated With Multihospital Implementation of Electronic Antimicrobial Stewardship Tools.

BACKGROUND: Antimicrobial stewards may benefit from comparative data to inform interventions that promote optimal inpatient antimicrobial use. METHODS: Antimicrobial stewards from 8 geographically dispersed Veterans Affairs (VA) inpatient facilities participated in the development of antimicrobial use visualization tools that allowed for comparison to facilities of similar complexity. The visualization tools consisted of an interactive web-based antimicrobial dashboard and, later, a standardized antimicrobial usage report updated at user-selected intervals. Stewards participated in monthly learning collaboratives. The percent change in average monthly antimicrobial use (all antimicrobial agents, anti-methicillin-resistant Staphylococcus aureus [anti-MRSA] agents, and antipseudomonal agents) was analyzed using a pre-post (January 2014-January 2016 vs July 2016-January 2018) design with segmented regression and external comparison with uninvolved control facilities (n = 118). RESULTS: Intervention sites demonstrated a 2.1% decrease (95% confidence interval [CI], -5.7% to 1.6%) in total antimicrobial use pre-post intervention vs a 2.5% increase (95% CI, 0.8% to 4.1%) in nonintervention sites (absolute difference, 4.6%; P = .025). Anti-MRSA antimicrobial use decreased 11.3% (95% CI, -16.0% to -6.3%) at intervention sites vs a 6.6% decrease (95% CI, -9.1% to -3.9%) at nonintervention sites (absolute difference, 4.7%; P = .092). Antipseudomonal antimicrobial use decreased 3.4% (95% CI, -8.2% to 1.7%) at intervention sites vs a 3.6% increase (95% CI, 0.8% to 6.5%) at nonintervention sites (absolute difference, 7.0%; P = .018). CONCLUSIONS: Comparative data visualization tool use by stewards at 8 VA facilities was associated with significant reductions in overall antimicrobial and antipseudomonal use relative to uninvolved facilities.

Multidrug-resistant gram-negative organisms and association with 1-year mortality, readmission, and length of stay in Veterans with spinal cord injuries and disorders.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: The goal of this study was to assess the impact of multidrug resistant gram-negative organisms (MDRGNOs) on outcomes in those with SCI/D. SETTING: VA SCI System of Care, Department of Veterans Affairs, United States. METHODS: Multidrug resistance (MDR) was defined as being non-susceptible to ≥1 antibiotic in ≥3 antibiotic classes. Multivariable cluster-adjusted regression models were fit to assess the association of MDRGNOs with 1-year mortality, 30-day readmission, and postculture length of stay (LOS) stratified by case setting patients. Only the first culture per patient during the study period was included. RESULTS: A total of 8,681 individuals with SCI/D had a culture with gram-negative bacteria during the study period, of which 33.0% had a MDRGNO. Overall, 954 (10.9%) died within 1 year of culture date. Poisson regression showed that MDR was associated with 1-year mortality among outpatients (IRR: 1.28, 95% CI, 1.06-1.54) and long-term care patients (OR: 2.06, 95% CI, 1.28-3.31). MDR significantly impacted postculture LOS in inpatients, as evidenced by a 10% longer LOS in MDR vs. non-MDR (IRR: 1.10, 95% CI, 1.02-1.19). MDR was not associated with increased 30-day readmission. CONCLUSIONS: MDRGNOs are prevalent in SCI/D and MDR may result in poor outcomes. Further attention to prevention of infections, antibiotic stewardship, and management are warranted in this population.

In Data We Trust? Comparison of Electronic Versus Manual Abstraction of Antimicrobial Prescribing Quality Metrics for Hospitalized Veterans With Pneumonia.

BACKGROUND: Electronic health records provide the opportunity to assess system-wide quality measures. Veterans Affairs Pharmacy Benefits Management Center for Medication Safety uses medication use evaluation (MUE) through manual review of the electronic health records. OBJECTIVE: To compare an electronic MUE approach versus human/manual review for extraction of antibiotic use (choice and duration) and severity metrics. RESEARCH DESIGN: Retrospective. SUBJECTS: Hospitalizations for uncomplicated pneumonia occurring during 2013 at 30 Veterans Affairs facilities. MEASURES: We compared summary statistics, individual hospitalization-level agreement, facility-level consistency, and patterns of variation between electronic and manual MUE for initial severity, antibiotic choice, daily clinical stability, and antibiotic duration. RESULTS: Among 2004 hospitalizations, electronic and manual abstraction methods showed high individual hospitalization-level agreement for initial severity measures (agreement=86%-98%, κ=0.5-0.82), antibiotic choice (agreement=89%-100%, κ=0.70-0.94), and facility-level consistency for empiric antibiotic choice (anti-MRSA r=0.97, P<0.001; antipseudomonal r=0.95, P<0.001) and therapy duration (r=0.77, P<0.001) but lower facility-level consistency for days to clinical stability (r=0.52, P=0.006) or excessive duration of therapy (r=0.55, P=0.005). Both methods identified widespread facility-level variation in antibiotic choice, but we found additional variation in manual estimation of excessive antibiotic duration and initial illness severity. CONCLUSIONS: Electronic and manual MUE agreed well for illness severity, antibiotic choice, and duration of therapy in pneumonia at both the individual and facility levels. Manual MUE showed additional reviewer-level variation in estimation of initial illness severity and excessive antibiotic use. Electronic MUE allows for reliable, scalable tracking of national patterns of antimicrobial use, enabling the examination of system-wide interventions to improve quality.

Management of Bacteriuria in Veterans Affairs Hospitals.

BACKGROUND: Bacteriuria contributes to antibiotic overuse through treatment of asymptomatic bacteriuria (ASB) and long durations of therapy for symptomatic urinary tract infections (UTIs), yet large-scale evaluations of bacteriuria management among inpatients are lacking. METHODS: Inpatients with bacteriuria were classified as asymptomatic or symptomatic based on established criteria applied to data collected by manual chart review. We examined frequency of treatment of ASB, factors associated with treatment of ASB, durations of therapy, and frequency of complications including Clostridium difficile infection, readmission, and all-cause mortality within 28 days of discharge. RESULTS: Among 2225 episodes of bacteriuria, 64% were classified as ASB. After excluding patients with non-UTI indications for antibiotics, 72% of patients with ASB received antibiotics. When evaluating only patients not meeting SIRS criteria, 68% of patients with ASB received antibiotics. The mean (±SD) days of antibiotic therapy for ASB, cystitis, CA-UTI and pyelonephritis were 10.0 (4.5), 11.4 (4.7), 12.0 (6.1), and 13.6 (5.3), respectively. In sum, 14% of patients with ASB were treated for greater than 14 days, and fluoroquinolones were the most commonly used empiric antibiotic for ASB [245/691 (35%)]. Complications were rare but more common among patients with ASB treated with antibiotics. CONCLUSIONS: The majority of bacteriuria among inpatient veterans is due to ASB with high rates of treatment of ASB and prolonged durations of therapy for ASB and symptomatic UTIs.

Antimicrobial Nonsusceptibility of Gram-Negative Bloodstream Isolates, Veterans Health Administration System, United States, 2003-20131.

Bacteremia caused by gram-negative bacteria is associated with serious illness and death, and emergence of antimicrobial drug resistance in these bacteria is a major concern. Using national microbiology and patient data for 2003-2013 from the US Veterans Health Administration, we characterized nonsusceptibility trends of community-acquired, community-onset; healthcare-associated, community-onset; and hospital-onset bacteremia for selected gram-negative bacteria (Escherichia coli, Klebsiella spp., Pseudomonas aeruginosa, and Acinetobacter spp.). For 47,746 episodes of bacteremia, the incidence rate was 6.37 episodes/10,000 person-years for community-onset bacteremia and 4.53 episodes/10,000 patient-days for hospital-onset bacteremia. For Klebsiella spp., P. aeruginosa, and Acinetobacter spp., we observed a decreasing proportion of nonsusceptibility across nearly all antimicrobial drug classes for patients with healthcare exposure; trends for community-acquired, community-onset isolates were stable or increasing. The role of infection control and antimicrobial stewardship efforts in inpatient settings in the decrease in drug resistance rates for hospital-onset isolates needs to be determined.

Translation of Contextual Control Model to chronic disease management: A paradigm to guide design of cognitive support systems.

BACKGROUND: Electronic health records (EHRs) continue to be criticized for providing poor cognitive support. Defining cognitive support has lacked theoretical foundation. We developed a measurement model of cognitive support based on the Contextual Control Model (COCOM), which describes control characteristics of an "orderly" joint system and proposes 4 levels of control: scrambled, opportunistic, tactical, and strategic. METHODS: 35 clinicians (5 centers) were interviewed pre and post outpatient clinical visits and audiotaped during the visit. Behaviors pertaining to hypertension management were systematically mapped to the COCOM control characteristics of: (1) time horizon, (2) uncertainty assessment, (3) consideration of multiple goals, (4) causal model described, and (5) explicitness of plan. Each encounter was classified for overall mode of control. Visits with deviation versus no deviation from hypertension goals were compared. RESULTS: Reviewer agreement was high. Control characteristics differed significantly between deviation groups (Wilcox rank sum p<.01). K-means cluster analysis of control characteristics, stratified by deviation were distinct, with higher goal deviations associated with more control characteristics. CONCLUSION: The COCOM control characteristics appear to be areas of potential yield for improved user-experience design.

The Effect of a Nationwide Infection Control Program Expansion on Hospital-Onset Gram-Negative Rod Bacteremia in 130 Veterans Health Administration Medical Centers: An Interrupted Time-Series Analysis.

BACKGROUND: The Veterans Health Administration (VHA) introduced the Methicillin-Resistant Staphylococcus aureus (MRSA) Prevention Initiative in March 2007. Although the initiative has been perceived as a vertical intervention focusing on MRSA, it also expanded infection prevention and control programs and resources. We aimed to assess the horizontal effect of the initiative on hospital-onset (HO) gram-negative rod (GNR) bacteremia. METHODS: This retrospective cohort included all patients who had HO bacteremia due to Escherichia coli, Klebsiella species, or Pseudomonas aeruginosa at 130 VHA facilities from January 2003 to December 2013. The effects were assessed using segmented linear regression with autoregressive error models, incorporating autocorrelation, immediate effect, and time before and after the initiative. Community-acquired (CA) bacteremia with same species was also analyzed as nonequivalent dependent controls. RESULTS: A total of 11 196 patients experienced HO-GNR bacteremia during the study period. There was a significant change of slope in HO-GNR bacteremia incidence rates from before the initiative (+0.3%/month) to after (-0.4%/month) (P < .01), while CA GNR incidence rates did not significantly change (P = .08). Cumulative effect of the intervention on HO-GNR bacteremia incidence rates at the end of the study period was estimated to be -43.2% (95% confidence interval, -51.6% to -32.4%). Similar effects were observed in subgroup analyses of each species and antimicrobial susceptibility profile. CONCLUSIONS: Within 130 VHA facilities, there was a sustained decline in HO-GNR bacteremia incidence rates after the implementation of the MRSA Prevention Initiative. As these organisms were not specifically targeted, it is likely that horizontal components of the initiative contributed to this decline.

Variation in Outpatient Antibiotic Prescribing for Acute Respiratory Infections in the Veteran Population: A Cross-sectional Study.

BACKGROUND: Despite efforts to reduce antibiotic prescribing for acute respiratory infections (ARIs), information on factors that drive prescribing is limited. OBJECTIVE: To examine trends in antibiotic prescribing in the Veterans Affairs population over an 8-year period and to identify patient, provider, and setting sources of variation. DESIGN: Retrospective, cross-sectional study. SETTING: All emergency departments and primary and urgent care clinics in the Veterans Affairs health system. PARTICIPANTS: All patient visits between 2005 and 2012 with primary diagnoses of ARIs that typically had low proportions of bacterial infection. Patients with infections or comorbid conditions that indicated antibiotic use were excluded. MEASUREMENTS: Overall antibiotic prescription; macrolide prescription; and patient, provider, and setting characteristics extracted from the electronic health record. RESULTS: The proportion of 1 million visits with ARI diagnoses that resulted in antibiotic prescriptions increased from 67.5% in 2005 to 69.2% in 2012 (P < 0.001). The proportion of macrolide antibiotics prescribed increased from 36.8% to 47.0% (P < 0.001). Antibiotic prescribing was highest for sinusitis (adjusted proportion, 86%) and bronchitis (85%) and varied little according to fever, age, setting, or comorbid conditions. Substantial variation was identified in prescribing at the provider level: The 10% of providers who prescribed the most antibiotics did so during at least 95% of their ARI visits, and the 10% who prescribed the least did so during 40% or fewer of their ARI visits. LIMITATION: Some clinical data that may have influenced the prescribing decision were missing. CONCLUSION: Veterans with ARIs commonly receive antibiotics, regardless of patient, provider, or setting characteristics. Macrolide use has increased, and substantial variation was identified in antibiotic prescribing at the provider level. PRIMARY FUNDING SOURCE: U.S. Department of Veterans Affairs, Centers for Disease Control and Prevention.

Trends in Antibiotic Use and Nosocomial Pathogens in Hospitalized Veterans With Pneumonia at 128 Medical Centers, 2006-2010.

BACKGROUND: In 2005, pneumonia practice guidelines recommended broad-spectrum antibiotics for patients with risk factors for nosocomial pathogens. The impact of these recommendations on the ability of providers to match treatment with nosocomial pathogens is unknown. METHODS: Among hospitalizations with a principal diagnosis of pneumonia at 128 Department of Veterans Affairs medical centers from 2006 through 2010, we measured annual trends in antibiotic selection; initial blood or respiratory cultures positive for methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, and Acinetobacter species; and alignment between antibiotic coverage and culture results for MRSA and P. aeruginosa, calculating sensitivity, specificity, and diagnostic odds ratio using a 2 × 2 contingency table. RESULTS: In 95 511 hospitalizations for pneumonia, initial use of vancomycin increased from 16% in 2006 to 31% in 2010, and piperacillin-tazobactam increased from 16% to 27%, and there was a decrease in both ceftriaxone (from 39% to 33%) and azithromycin (change from 39% to 36%) (P < .001 for all). The proportion of hospitalizations with cultures positive for MRSA decreased (from 2.5% to 2.0%; P < .001); no change was seen for P. aeruginosa (1.9% to 2.0%; P = .14) or Acinetobacter spp. (0.2% to 0.2%; P = .17). For both MRSA and P. aeruginosa, sensitivity increased (from 46% to 65% and 54% to 63%, respectively; P < .001) and specificity decreased (from 85% to 69% and 76% to 68%; P < .001), with no significant changes in diagnostic odds ratio (decreases from 4.6 to 4.1 [P = .57] and 3.7 to 3.2 [P = .95], respectively). CONCLUSIONS: Between 2006 and 2010, we found a substantial increase in the use of broad-spectrum antibiotics for pneumonia despite no increase in nosocomial pathogens. The ability of providers to accurately match antibiotic coverage to nosocomial pathogens remains low.

Taking an Antibiotic Time-out: Utilization and Usability of a Self-Stewardship Time-out Program for Renewal of Vancomycin and Piperacillin-Tazobactam.

BACKGROUND: Antibiotic time-outs can promote critical thinking and greater attention to reviewing indications for continuation. OBJECTIVE: We pilot tested an antibiotic time-out program at a tertiary care teaching hospital where vancomycin and piperacillin-tazobactam continuation past day 3 had previously required infectious diseases service approval. METHODS: The time-out program consisted of 3 components: (1) an electronic antimicrobial dashboard that aggregated infection-relevant clinical data; (2) a templated note in the electronic medical record that included a structured review of antibiotic indications and that provided automatic approval of continuation of therapy when indicated; and (3) an educational and social marketing campaign. RESULTS: In the first 6 months of program implementation, vancomycin was discontinued by day 5 in 93/145 (64%) courses where a time-out was performed on day 4 versus in 96/199 (48%) 1 year prior (P = .04). Seven vancomycin continuations via template (5% of time-outs) were guideline-discordant by retrospective chart review versus none 1 year prior (P = .002). Piperacillin-tazobactam was discontinued by day 5 in 70/105 (67%) courses versus 58/93 (62%) 1 year prior (P = .55); 9 continuations (9% of time-outs) were guideline-discordant versus two 1 year prior (P = .06). A usability survey completed by 32 physicians demonstrated modest satisfaction with the overall program, antimicrobial dashboard, and renewal templates. CONCLUSIONS: By providing practitioners with clinical informatics support and guidance, the intervention increased provider confidence in making decisions to de-escalate antimicrobial therapy in ambiguous circumstances wherein they previously sought authorization for continuation from an antimicrobial steward.

Automating detection of diagnostic error of infectious diseases using machine learning.

Diagnostic error, a cause of substantial morbidity and mortality, is largely discovered and evaluated through self-report and manual review, which is costly and not suitable to real-time intervention. Opportunities exist to leverage electronic health record data for automated detection of potential misdiagnosis, executed at scale and generalized across diseases. We propose a novel automated approach to identifying diagnostic divergence considering both diagnosis and risk of mortality. Our objective was to identify cases of emergency department infectious disease misdiagnoses by measuring the deviation between predicted diagnosis and documented diagnosis, weighted by mortality. Two machine learning models were trained for prediction of infectious disease and mortality using the first 24h of data. Charts were manually reviewed by clinicians to determine whether there could have been a more correct or timely diagnosis. The proposed approach was validated against manual reviews and compared using the Spearman rank correlation. We analyzed 6.5 million ED visits and over 700 million associated clinical features from over one hundred emergency departments. The testing set performances of the infectious disease (Macro F1 = 86.7, AUROC 90.6 to 94.7) and mortality model (Macro F1 = 97.6, AUROC 89.1 to 89.1) were in expected ranges. Human reviews and the proposed automated metric demonstrated positive correlations ranging from 0.231 to 0.358. The proposed approach for diagnostic deviation shows promise as a potential tool for clinicians to find diagnostic errors. Given the vast number of clinical features used in this analysis, further improvements likely need to either take greater account of data structure (what occurs before when) or involve natural language processing. Further work is needed to explain the potential reasons for divergence and to refine and validate the approach for implementation in real-world settings.

Development and implementation of a nationwide multidrug-resistant organism tracking and alert system for Veterans Affairs medical centers.

OBJECTIVE: Develop and implement a system in the Veterans Health Administration (VA) to alert local medical center personnel in real time when an acute- or long-term care patient/resident is admitted to their facility with a history of colonization or infection with a multidrug-resistant organism (MDRO) previously identified at any VA facility across the nation. METHODS: An algorithm was developed to extract clinical microbiology and local facility census data from the VA Corporate Data Warehouse initially targeting carbapenem-resistant Enterobacterales (CRE) and methicillin-resistant Staphylococcus aureus (MRSA). The algorithm was validated with chart review of CRE cases from 2010-2018, trialed and refined in 24 VA healthcare systems over two years, expanded to other MDROs and implemented nationwide on 4/2022 as "VA Bug Alert" (VABA). Use through 8/2023 was assessed. RESULTS: VABA performed well for CRE with recall of 96.3%, precision of 99.8%, and F1 score of 98.0%. At the 24 trial sites, feedback was recorded for 1,011 admissions with a history of CRE (130), MRSA (814), or both (67). Among Infection Preventionists and MDRO Prevention Coordinators, 338 (33%) reported being previously unaware of the information, and of these, 271 (80%) reported they would not have otherwise known this information. By fourteen months after nationwide implementation, 113/130 (87%) VA healthcare systems had at least one VABA subscriber. CONCLUSIONS: A national system for alerting facilities in real-time of patients admitted with an MDRO history was successfully developed and implemented in VA. Next steps include understanding facilitators and barriers to use and coordination with non-VA facilities nationwide.

Incorporating social determinants of health into transmission modeling of COVID-19 vaccine in the US: a scoping review.

During COVID-19 in the US, social determinants of health (SDH) have driven health disparities. However, the use of SDH in COVID-19 vaccine modeling is unclear. This review aimed to summarize the current landscape of incorporating SDH into COVID-19 vaccine transmission modeling in the US. Medline and Embase were searched up to October 2022. We included studies that used transmission modeling to assess the effects of COVID-19 vaccine strategies in the US. Studies' characteristics, factors incorporated into models, and approaches to incorporate these factors were extracted. Ninety-two studies were included. Of these, 11 studies incorporated SDH factors (alone or combined with demographic factors). Various sets of SDH factors were integrated, with occupation being the most common (8 studies), followed by geographical location (5 studies). The results show that few studies incorporate SDHs into their models, highlighting the need for research on SDH impact and approaches to incorporating SDH into modeling. Funding: This research was funded by the Centers for Disease Control and Prevention (CDC).

Development and validation of a standardized blood culture contamination definition and metric dashboard for a large health care system.

OBJECTIVES: Blood culture contamination is a major problem in health care, with significant impacts on both patient safety and cost. Initiatives to reduce blood culture contamination require a reliable, consistent metric to track the success of interventions. The objective of our project was to establish a standardized definition of blood culture contamination suitable for use in a Veterans Health Administration (VHA) national data query, then to validate this definition and query. A secondary objective was to construct a national VHA data dashboard to display the data from this query that could be used in VHA quality improvement projects aimed at reducing blood culture contamination. METHODS: A VHA microbiology expert work group was formed to generate a standardized definition and oversee the validation studies. The standardized definition was used to generate data for calendar year 2021 using a Structured Query Language data query. Twelve VHA hospital microbiology laboratories compared the data from the query against their own locally derived contamination data and recorded those data in a data collection worksheet that all sites used. Data were collated and presented to the work group. RESULTS: More than 50,000 blood culture accessions were in the validation data set, with more than 1,200 contamination events. The overall blood culture contamination rate for the 12 facilities participating was 2.56% with local definitions and data and 2.43% with the standardized definitions and data query. The main differences noted between the 2 data sets were deemed to be issues in local definitions. The query and definition were then converted into a national data dashboard that all VHA facilities can now access. CONCLUSIONS: A standardized definition for blood culture contamination and a national data query were validated for enterprise-wide VHA use. To our knowledge, this represents the first reported standardized, validated, and automated approach for calculating and tracking blood culture contamination. This tool will be key in quality initiatives aimed at reducing contamination events in VHA.

Performance of infectious diseases specialists, hospitalists, and other internal medicine physicians in antimicrobial case-based scenarios: Potential impact of antimicrobial stewardship programs at 16 Veterans' Affairs medical centers.

OBJECTIVE: As part of a project to implement antimicrobial dashboards at select facilities, we assessed physician attitudes and knowledge regarding antibiotic prescribing. DESIGN: An online survey explored attitudes toward antimicrobial use and assessed respondents' management of four clinical scenarios: cellulitis, community-acquired pneumonia, non-catheter-associated asymptomatic bacteriuria, and catheter-associated asymptomatic bacteriuria. SETTING: This study was conducted across 16 Veterans' Affairs (VA) medical centers in 2017. PARTICIPANTS: Physicians working in inpatient settings specializing in infectious diseases (ID), hospital medicine, and non-ID/hospitalist internal medicine. METHODS: Scenario responses were scored by assigning +1 for answers most consistent with guidelines, 0 for less guideline-concordant but acceptable answers and -1 for guideline-discordant answers. Scores were normalized to 100% guideline concordant to 100% guideline discordant across all questions within a scenario, and mean scores were calculated across respondents by specialty. Differences in mean score per scenario were tested using analysis of variance (ANOVA). RESULTS: Overall, 139 physicians completed the survey (19 ID physicians, 62 hospitalists, and 58 other internists). Attitudes were similar across the 3 groups. We detected a significant difference in cellulitis scenario scores (concordance: ID physicians, 76%; hospitalists, 58%; other internists, 52%; P = .0087). Scores were numerically but not significantly different across groups for community-acquired pneumonia (concordance: ID physicians, 75%; hospitalists, 60%; other internists, 56%; P = .0914), for non-catheter-associated asymptomatic bacteriuria (concordance: ID physicians, 65%; hospitalists, 55%; other internists, 40%; P = .322), and for catheter-associated asymptomatic bacteriuria (concordance: ID physicians, 27% concordant; hospitalists, 8% discordant; other internists 13% discordant; P = .12). CONCLUSIONS: Significant differences in performance regarding management of cellulitis and low overall performance regarding asymptomatic bacteriuria point to these conditions as being potentially high-yield targets for stewardship interventions.