OBJECTIVE: To conduct a process evaluation of a respiratory culture diagnostic stewardship intervention.

DESIGN: Mixed-methods study.

SETTING: Tertiary-care pediatric intensive care unit (PICU).

PARTICIPANTS: Critical care, infectious diseases, and pulmonary attending physicians and fellows; PICU nurse practitioners and hospitalist physicians; pediatric residents; and PICU nurses and respiratory therapists.

METHODS: This mixed-methods study was conducted concurrently with a diagnostic stewardship intervention to reduce the inappropriate collection of respiratory cultures in mechanically ventilated children. We quantified baseline respiratory culture utilization and indications for ordering using quantitative methods. Semistructured interviews informed by these data and the Consolidated Framework for Implementation Research (CFIR) were then performed, recorded, transcribed, and coded to identify salient themes. Finally, themes identified in these interviews were used to create a cross-sectional survey.

RESULTS: The number of cultures collected per day of service varied between attending physicians (range, 2.2-27 cultures per 100 days). In total, 14 interviews were performed, and 87 clinicians completed the survey (response rate, 47%) and 77 nurses or respiratory therapists completed the survey (response rate, 17%). Clinicians varied in their stated practices regarding culture ordering, and these differences both clustered by specialty and were associated with perceived utility of the respiratory culture. Furthermore, group "default" practices, fear, and hierarchy were drivers of culture orders. Barriers to standardization included fear of a missed diagnosis and tension between practice standardization and individual decision making.

CONCLUSIONS: We identified significant variation in utilization and perceptions of respiratory cultures as well as several key barriers to implementation of this diagnostic test stewardship intervention.

<p><strong>BACKGROUND AND OBJECTIVES: </strong>With the onset of the coronavirus disease 2019 (COVID-19) pandemic, pediatric ambulatory encounter volume and antibiotic prescribing both decreased; however, the durability of these reductions in pediatric primary care in the United States has not been assessed.</p>

<p><strong>METHODS: </strong>We conducted a retrospective observational study to assess the impact of the COVID-19 pandemic and associated public health measures on antibiotic prescribing in 27 pediatric primary care practices. Encounters from January 1, 2018, through June 30, 2021, were included. The primary outcome was monthly antibiotic prescriptions per 1000 patients. Interrupted time series analysis was performed.</p>

<p><strong>RESULTS: </strong>There were 69 327 total antibiotic prescriptions from April through December in 2019 and 18 935 antibiotic prescriptions during the same months in 2020, a 72.7% reduction. The reduction in prescriptions at visits for respiratory tract infection (RTI) accounted for 87.3% of this decrease. Using interrupted time series analysis, overall antibiotic prescriptions decreased from 31.6 to 6.4 prescriptions per 1000 patients in April 2020 (difference of -25.2 prescriptions per 1000 patients; 95% CI: -32.9 to -17.5). This was followed by a nonsignificant monthly increase in antibiotic prescriptions, with prescribing beginning to rebound from April to June 2021. Encounter volume also immediately decreased, and while overall encounter volume quickly started to recover, RTI encounter volume returned more slowly.</p>

<p><strong>CONCLUSIONS: </strong>Reductions in antibiotic prescribing in pediatric primary care during the COVID-19 pandemic were sustained, only beginning to rise in 2021, primarily driven by reductions in RTI encounters. Reductions in viral RTI transmission likely played a substantial role in reduced RTI visits and antibiotic prescriptions.</p>