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

Retrospective cohort study.

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

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.

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).

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.

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.

To assess the impact of a diagnostic test stewardship intervention focused on tracheal aspirate cultures.

Quality improvement intervention.

Tertiary care pediatric intensive care unit (PICU).

Mechanically ventilated children admitted between 9/2018 and 8/2022.

We developed and implemented a consensus guideline for obtaining tracheal aspirate cultures through a series of Plan-Do-Study-Act cycles. Change in culture rates and broad-spectrum antibiotic days of therapy (DOT) per 100 ventilator days were analyzed using statistical process control charts. A secondary analysis comparing the preintervention baseline (9/2018–8/2020) to the postintervention period (9/2020–8/2021) was performed using Poisson regression.

The monthly tracheal aspirate culture rate prior to the COVID-19 pandemic (9/2018–3/2020) was 4.6 per 100 ventilator days. A centerline shift to 3.1 cultures per 100 ventilator days occurred in 4/2020, followed by a second shift to 2.0 cultures per 100 ventilator days in 12/2020 after guideline implementation. In our secondary analysis, the monthly tracheal aspirate culture rate decreased from 4.3 cultures preintervention (9/2018–8/2020) to 2.3 cultures per 100 ventilator days postintervention (9/2020–8/2021) (IRR 0.52, 95% CI 0.47–0.59, P < 0.01). Decreases in tracheal aspirate culture use were driven by decreases in inappropriate cultures. Treatment of ventilator-associated infections decreased from 1.0 to 0.7 antibiotic courses per 100 ventilator days (P = 0.03). There was no increase in mortality, length of stay, readmissions, or ventilator-associated pneumonia postintervention.

A diagnostic test stewardship intervention was both safe and effective in reducing the rate of tracheal aspirate cultures and treatment of ventilator-associated infections in a tertiary PICU.

To evaluate the comparative epidemiology of hospital-onset bloodstream infection (HOBSI) and central line-associated bloodstream infection (CLABSI)

Retrospective observational study of HOBSI and CLABSI across a three-hospital healthcare system from 01/01/2017 to 12/31/2021

HOBSIs were identified as any non-commensal positive blood culture event on or after hospital day 3. CLABSIs were identified based on National Healthcare Safety Network (NHSN) criteria. We performed a time-series analysis to assess comparative temporal trends among HOBSI and CLABSI incidence. Using univariable and multivariable regression analyses, we compared demographics, risk factors, and outcomes between non-CLABSI HOBSI and CLABSI, as HOBSI and CLABSI are not exclusive entities.

HOBSI incidence increased over the study period (IRR 1.006 HOBSI/1,000 patient days; 95% CI 1.001–1.012; P = .03), while no change in CLABSI incidence was observed (IRR .997 CLABSIs/1,000 central line days, 95% CI .992–1.002, P = .22). Differing demographic, microbiologic, and risk factor profiles were observed between CLABSIs and non-CLABSI HOBSIs. Multivariable analysis found lower odds of mortality among patients with CLABSIs when adjusted for covariates that approximate severity of illness (OR .27; 95% CI .11–.64; P < .01).

HOBSI incidence increased over the study period without a concurrent increase in CLABSI in our study population. Furthermore, risk factor and outcome profiles varied between CLABSI and non-CLABSI HOBSI, which suggest that these metrics differ in important ways worth considering if HOBSI is adopted as a quality metric.

Evidence-based central-line–associated bloodstream infection (CLABSI) prevention guidelines recommend the use of an antiseptic scrub to disinfect needleless connectors before device access. Guideline noncompliance may render disinfection ineffective. The goal of this study was to observe needleless-connector disinfection practices and to identify perceived facilitators and barriers to best practices of needleless-connector access.

A human factors mixed-methods study involving nursing focus groups of perceived barriers and facilitators and clinical observations of compliance with instructions and protocols for use of 3.15% chlorhexidine gluconate/70% isopropyl alcohol (CHG/IPA) and 70% isopropyl alcohol (IPA) antisepsis products for central venous access device (CVAD) needleless-connector disinfection was conducted in intensive care units (ICUs) at 2 academic medical centers.

Access to the antiseptic product and lesser workload were identified as best-practice facilitators. Barriers were the time required per needleless-connector access and knowledge deficits. Of the 48 observed access events, 77% resulted in needleless-connector disinfection. The observed mean needleless-connector scrubbing times when using IPA were substantially below the recommended time. Drying time after product use was negligible.

Lack of access to the disinfection product, emergency situations, and high workload were barriers to needleless-connector disinfection. Observed scrubbing and drying times were shorter than recommended, especially for IPA wipes. These needleless-connector disinfection deficits may increase the risk of CLABSI. Ongoing education and periodic competency evaluation of needleless-connector disinfection, improvement of supply management, and staffing workload are required to imbed and sustain best practices. Further study involving a larger sample size in diverse patient populations is warranted.

Whole-genome sequencing (WGS) has emerged as an alternative genotyping tool for outbreak investigations in the healthcare setting. We describe the investigation and control of a New Delhi metallo-B-lactamase (NDM)-producing Escherichia coli cluster in Southeast Michigan.

Michigan Bureau of Laboratories identified several closely related NDM-producing E. coli isolates with WGS. An epidemiologic investigation, including case-control study, assessment of infection control practices, and endoscope culturing, was performed to identify source of transmission. Targeted screening of potentially exposed patients was performed following identification of probable source.

Between July 2021 and February 2023, nine patients were identified. Phylogenetic analysis confirmed the isolates were closely related with less than 26 single nucleotide polymorphism (SNP) differences between isolates, suggesting an epidemiological link. Eight (89%) patients had a duodenoscope and/or gastroscope exposure. Cases were compared with 23 controls. Cases had significantly higher odds of exposure to duodenoscopes (odds ratio 15.0; 95% CI, 1.8–142.2; P = .015). The mean incubation period, estimated as date of procedure to positive index culture, was 86 days (range, 1–320 days). No lapses in endoscope reprocessing were identified; NDM-producing E. coli was not recovered from reprocessed endoscopes or during targeted screening. No additional cases were identified after removal of implicated gastroscopes and replacement of duodenoscope with disposable end caps.

In this investigation, WGS was utilized to identify transmission of an NDM-producing E. coli outbreak associated with endoscope exposure. Coupled with epidemiologic data, WGS can facilitate outbreak investigations by rapidly identifying linked cases and potential sources to prevent further transmission.

To investigate the source and transmission dynamics of an endoscope-associated New Delhi metallo-β-lactamase-producing Klebsiella pneumonia (NDM-KP) outbreak.

Epidemiological and genomic investigation.

Academic acute care hospital in New Jersey.

Five patients with active NDM-KP infection identified on clinical isolates, and four NDM-KP colonized patients identified via rectal swab screening.

Over a twelve-month period, nine patients were identified with NDM-KP infection or colonization. Whole-genome sequencing (WGS) revealed that all of the identified cases were related by 25 mutational events or less. Seven of the cases were linked to gastrointestinal endoscopic procedures (four clinical cases and three positive screens among patients exposed to endoscopes suspected of transmission). Two cases demonstrated delayed transmission that occurred five months after the initial outbreak, likely through shared usage of a non-therapeutic gastroscope without an elevator channel.

Although all endoscope cultures in our investigation were negative, the epidemiological link to gastrointestinal endoscopes, the high degree of relatedness via WGS, and the identification of asymptomatic NDM-KP colonization among patients exposed to shared endoscopes make the endoscopic mode of transmission most likely. This investigation highlights the probable transmission of NDM-KP via a gastroscope without an elevator channel, observed several months after an initial outbreak. We hypothesize that persistent mechanical defects may have contributed to the delayed device-related transmission of NDM-KP.

Older adults residing in congregate living settings (CLS) such as nursing homes and independent living facilities remain at increased risk of morbidity and mortality from coronavirus disease 2019. We performed a prospective multicenter study of consecutive severe acute respiratory coronavirus virus 2 (SARS-CoV-2) exposures to identify predictors of transmission in this setting.

Consecutive resident SARS-CoV-2 exposures across 17 CLS were prospectively characterized from 1 September 2022 to 1 March 2023, including factors related to environment, source, and exposed resident. Room size, humidity, and ventilation were measured in locations where exposures occurred. Predictors were incorporated in a generalized estimating equation model adjusting for the correlation within CLS.

Among 670 consecutive exposures to SARS-CoV-2 across 17 CLS, transmission occurred among 328 (49.0%). Increased risk was associated with nursing homes (odds ratio (OR) = 90.8; 95% CI, 7.8–1047.4), Jack and Jill rooms (OR = 2.2; 95% CI, 1.3–3.6), from source who was pre-symptomatic (OR = 11.2; 95% CI, 4.1–30.9), symptomatic (OR = 6.5; 95% CI, 1.4–29.9), or rapid antigen test positive (OR = 35.6; 95% CI, 5.6–225.6), and in the presence of secondary exposure (OR = 6.3; 95% CI, 1.6–24.0). Exposure in dining room was associated with reduced risk (OR = 0.02; 95% CI, 0.005–0.08) as was medium room size (OR = 0.3; 95% CI, 0.2–0.6). Recent vaccination of exposed resident (OR = 0.5; 95% CI, 0.3–1.0) and increased ventilation of room (OR = 0.9; 95% CI, 0.8–1.0) were marginally associated with reduced risk.

Prospective assessment of SARS-CoV-2 exposures in CLS suggests that source characteristics and location of exposure are most predictive of resident transmission. These findings can inform risk assessment and further opportunities to prevent transmission in CLS.