Diagnostic Stewardship in the Pediatric Intensive Care Unit

Evaluation of a Comprehensive Algorithm for PICU Patients With New Fever or Instability: Association of Clinical Decision Support With Testing Practices

OBJECTIVES

Previously, we implemented a comprehensive decision support tool, a "New Fever Algorithm," to support the evaluation of PICU patients with new fever or instability. This tool was associated with a decline in culture rates without safety concerns. We assessed the impact of the algorithm on testing practices by identifying the proportion of cultures pre- vs. post-implementation that were discordant with algorithm guidance and may have been avoidable.

DESIGN

Retrospective evaluation 12 months pre- vs. post-quality improvement intervention.

SETTING

Single-center academic PICU and pediatric cardiac ICU.

SUBJECTS

All admitted patients.

INTERVENTIONS

Implementing the "New Fever Algorithm" in July 2020.

MEASUREMENTS AND MAIN RESULTS

Patient medical records were reviewed to categorize indications for all blood, respiratory, and urine cultures. Among cultures obtained for new fever or new clinical instability, we assessed specific testing patterns that were discordant from the algorithm's guidance such as blood cultures obtained without documented concern for sepsis without initiation of antibiotics, respiratory cultures without respiratory symptoms, urine cultures without a urinalysis or pyuria, and pan-cultures (concurrent blood, respiratory, and urine cultures). Among 2827 cultures, 1950 (69%) were obtained for new fever or instability. The proportion of peripheral blood cultures obtained without clinical concern for sepsis declined from 18.6% to 10.4% (p < 0.0007). Respiratory cultures without respiratory symptoms declined from 41.5% to 27.4% (p = 0.01). Urine cultures without a urinalysis did not decline (from 27.6% to 25.1%). Urine cultures without pyuria declined from 83.0% to 73.7% (p = 0.04). Pan-cultures declined from 22.4% to 10.6% (p < 0.0001). Overall, algorithm-discordant testing declined from 39% to 30% (p < 0.0001).

CONCLUSIONS

The majority of cultures obtained were for new fever or instability and introduction of the "New Fever Algorithm" was associated with reductions in algorithm-discordant testing practices and pan-cultures. There remain opportunities for improvement and additional strategies are warranted to optimize testing practices for in this complex patient population.

Repeat tracheal aspirate cultures in pediatric intensive care patients: Frequency, resistance, and antimicrobial use

OBJECTIVE

To evaluate the clinical impact and features associated with repeat tracheal aspirate (TA) cultures in children admitted to the intensive care unit.

DESIGN

Retrospective cohort study.

SETTING

A 338-bed freestanding, tertiary pediatric academic medical center with pediatric medical intensive care unit (PICU) and cardiac intensive care units (CICU).

PATIENTS

Children ≤18 years of age who were admitted to either the PICU or CICU who had ≥2 TA cultures in a single intensive care admission.

METHODS

Patients with ≥2 TA cultures between 2018 and 2019 were included in this study. The following information was collected: patient demographics, clinical data summarizing patient condition at the time of culture collection, number of TA cultures per patient, antibiotic usage, and microbiologic data. Descriptive statistics established the frequency of TA collection, time between culturing, clinical reasoning for collection, antibiotic exposure, and development of multidrug-resistant organisms (MDRO).

RESULTS

Sixty-three patients had repeat TA cultures and accounted for 252 TA cultures during the study period. Most patients with repeat TA cultures were admitted to the PICU (71%) and were male (65%). A median of 3 TA cultures per patient were obtained with 50% of repeat cultures occurring within 7 days from the previous culture. Sixty-six percent of patients had the same organism cultured on ≥2 TA cultures. Most antibiotics were not modified or continued to treat the results of the TA culture.

CONCLUSIONS

Repeat TA cultures frequently show the same pathogens, and results do not often influence antibiotic selection or usage. Repeat TA cultures did demonstrate the development of MDROs.

Antimicrobial Stewardship and Improved Antibiotic Utilization in the Pediatric Cardiac Intensive Care Unit

Background

We developed a multidisciplinary antimicrobial stewardship team to optimize antimicrobial use within the Pediatric Cardiac Intensive Care Unit. A quality improvement initiative was conducted to decrease unnecessary broad-spectrum antibiotic use by 20%, with sustained change over 12 months.

Methods

We conducted this quality improvement initiative within a quaternary care center. PDSA cycles focused on antibiotic overuse, provider education, and practice standardization. The primary outcome measure was days of therapy (DOT)/1000 patient days. Process measures included electronic medical record order-set use. Balancing measures focused on alternative antibiotic use, overall mortality, and sepsis-related mortality. Data were analyzed using statistical process control charts.

Results

A significant and sustained decrease in DOT was observed for vancomycin and meropenem. Vancomycin use decreased from a baseline of 198 DOT to 137 DOT, a 31% reduction. Meropenem use decreased from 103 DOT to 34 DOT, a 67% reduction. These changes were sustained over 24 months. The collective use of gram-negative antibiotics, including meropenem, cefepime, and piperacillin-tazobactam, decreased from a baseline of 323 DOT to 239 DOT, a reduction of 26%. There was no reciprocal increase in cefepime or piperacillin-tazobactam use. Key interventions involved electronic medical record changes, including automatic stop times and empiric antibiotic standardization. All-cause mortality remained unchanged.

Conclusions

The initiation of a dedicated antimicrobial stewardship initiative resulted in a sustained reduction in meropenem and vancomycin usage. Interventions did not lead to increased utilization of alternative broad-spectrum antimicrobials or increased mortality. Future interventions will target additional broad-spectrum antimicrobials.

Application of Participatory Ergonomics to the Dissemination of a Quality Improvement Program for Optimizing Blood Culture Use

BACKGROUND

Blood cultures are overused in pediatric ICUs (PICUs), which may lead to unnecessary antibiotic use and antibiotic resistance. Using a participatory ergonomics (PE) approach, the authors disseminated a quality improvement (QI) program for optimizing blood culture use in PICUs to a national 14-hospital collaborative. The objective of this study was to evaluate the dissemination process and its impact on blood culture reduction.

METHODS

The PE approach emphasized three key principles (stakeholder participation, application of human factors and ergonomics knowledge and tools, and cross-site collaboration) with a six-step dissemination process. Data on interactions between sites and the coordinating team and site experiences with the dissemination process were collected using site diaries and semiannual surveys with local QI teams, respectively, and correlated with the site-specific change in blood culture rates.

RESULTS

Overall, participating sites were able to successfully implement the program and reduced their blood culture rates from 149.4 blood cultures per 1,000 patient-days/month before implementation to 100.5 blood cultures per 1,000 patient-days/month after implementation, corresponding to a 32.7% relative reduction (p < 0.001). Variations in the dissemination process, as well as in local interventions and implementation strategies, were observed across sites. Site-specific changes in blood culture rates were weakly negatively correlated with the number of preintervention interactions with the coordinating team (p = 0.057) but not correlated with their experiences with the six domains of the dissemination process or their interventions.

CONCLUSIONS

The authors applied a PE approach to disseminate a QI program for optimizing PICU blood culture use to a multisite collaborative. Working with local stakeholders, participating sites tailored their interventions and implementation processes and achieved the goal of reducing blood culture use.

Comparison of Administrative Database-Derived and Hospital-Derived Data for Monitoring Blood Culture Use in the Pediatric Intensive Care Unit

BACKGROUND

Optimizing blood culture practices requires monitoring of culture use. Collecting culture data from electronic medical records can be resource intensive. Our objective was to determine whether administrative data could serve as a data source to measure blood culture use in pediatric intensive care units (PICUs).

METHODS

Using data from a national diagnostic stewardship collaborative to reduce blood culture use in PICUs, we compared the monthly number of blood cultures and patient-days collected from sites (site-derived) and the Pediatric Health Information System (PHIS, administrative-derived), an administrative data warehouse, for 11 participating sites. The collaborative's reduction in blood culture use was compared using administrative-derived and site-derived data.

RESULTS

Across all sites and months, the median of the monthly relative blood culture rate (ratio of administrative- to site-derived data) was 0.96 (Q1: 0.77, Q3: 1.24). The administrative-derived data produced an estimate of blood culture reduction over time that was attenuated toward the null compared with site-derived data.

CONCLUSIONS

Administrative data on blood culture use from the PHIS database correlates unpredictably with hospital-derived PICU data. The limitations of administrative billing data should be carefully considered before use for ICU-specific data.