Reducing blood culture contamination rates in the emergency department

Laboratory approaches to determining blood culture contamination rates: an ASM Laboratory Practices Subcommittee report

Blood culture contamination (BCC) is the presence of specific commensal and environmental organisms cultivated from a single blood culture set out of a blood culture series and that do not represent true bacteremia. BCC can impact quality of care and lead to negative outcomes, unnecessary antibiotic exposure, prolonged hospital stays, and substantial costs. As part of the laboratory's quality management plan, microbiology laboratory personnel are tasked with monitoring BCC rates, preparing BCC rate reports, and providing feedback to the appropriate committees within their healthcare system. The BCC rate is calculated by the laboratory using pre-set criteria. However, pre-set criteria are not universally defined and depend on the individual institution's patient population and practices. This mini-review provides practical recommendations on elaborating BCC rate reports, the parameters to define for the pre-set criteria, how to collect and interpret the data, and additional analysis to include in a BCC report.

A multi-pronged approach to improve blood culture diagnostics in different clinical departments: a single-centre experience

PURPOSE

Blood culture (BC) diagnostics are influenced by many factors. We performed a targeted interdisciplinary analysis to analyse effects of various measures on BC diagnostics performance.

METHODS

A diagnostic stewardship initiative was conducted at two intervention and two control wards in a German tertiary level hospital. The initiative comprised staff training on the correct indications and sampling for BC, implementation of information cards, labels to identify the collection site, regular BC bottle feedback including the number of bottles, filling volumes and identified pathogens; and the use of a specific sampling device (BD Vacutainer®). Before and after the interventions, two three-month measurement periods were performed, as well as a one-month follow-up period to assess the sustainability of the conducted measures.

RESULTS

In total, 9362 BC bottles from 787 patients were included in the analysis. The number of BCs obtained from peripheral venous puncture could be increased at both intervention wards (44.0 vs. 22.2%, 58.3 vs. 34.4%), while arterial sampling could be reduced (30.6 vs. 4.9%). A total of 134 staff members were fully trained. The intervention led to a considerable increase in BC knowledge (from 62.4 to 79.8% correct answers) with differences between the individual professional groups. Relevant reduced contamination rates could be detected at both intervention wards.

CONCLUSIONS

As knowledge on the correct BC sampling and strategies to reduce contamination varies considerably between clinical departments and healthcare professionals, a targeted training should be adapted to the specific needs of the individual professional groups. An additional filling device is not necessary.

Alterations in gene expression of recA and umuDC in antibiotic-resistant Acinetobacter baumannii

Acinetobacter baumannii is a critical pathogen with an efficient SOS (Save Our Ship) system that plays a significant role in antibiotic resistance. This prospective descriptive study aimed to investigate the association between expression levels of recA and umuDC genes, which are critical in SOS pathways, and antibiotic resistance in A. baumannii. We analyzed 78 clinical isolates and 31 ecological isolates using the Vitek-2 system for bacterial identification and antibiotic susceptibility testing and confirmed molecular identification of A. baumannii by conventional PCR of blaOXA-51 and blaOXA-23. Quantitative real-time polymerase chain reaction was used to determine gene expression levels of recA and umuDC. The results showed that in 25 clinical strains, 14/25 strains showed upregulation of recA, 7/25 strains exhibited upregulation of both umuDC and recA, and 1/25 strains showed upregulation of umuDC. Of these, 16/25 clinical strains were extensively resistant to antibiotics, except for colistin, and showed upregulation of recA and/or umuDC gene expression levels. In 6 ecological strains, recA showed upregulation in 3/6 strains, while both recA and umuDC were upregulated in 1/6 strain. In conclusion, high expression levels of recA and/or umuDC genes in A. baumannii complex and A. baumannii strains may contribute to increasing resistance to a wide range of antibiotics and may result in the initiation of an extensively drug-resistant (XDR) phenotype.

Effects of COVID-19 on Blood Culture Contamination at a Tertiary Care Academic Medical Center

The COVID-19 pandemic has changed health care, from increased needs of personal protective equipment (PPE) to overloaded staff and influxes of patients. Blood cultures are frequently used to detect bloodstream infections in critically ill patients, but it is unknown whether the COVID-19 pandemic has had an impact on blood culture contamination rates. A total of 88,332 blood cultures taken over a 33-month period were analyzed to compare blood culture contamination rates before the COVID-19 pandemic to rates during the pandemic. A significant increase in the average number of monthly nurse-drawn and peripherally collected cultures occurred after the start of the pandemic, but there was a decrease in the average number of phlebotomy cultures. A significant increase in contamination rates (P < 0.001) was found in all nonemergency hospital departments during the COVID-19 pandemic, increasing from 2.1% to 2.5%. Increased rates during the COVID-19 pandemic were also found for nursing staff (2.0% to 2.4%) and both peripheral (2.1% to 2.5%) and indwelling line draws (1.1% to 1.7). The number of cultures drawn monthly increased in acute adult departments and both adult and pediatric emergency departments. Blood culture contamination rates in adult acute, adult emergency, and pediatric intensive care units increased after the start of the pandemic by 23%, 75%, and 59%, respectively. A positive correlation was found between blood culture contamination rates and COVID-19 incidence rates. Additional periodic staff training on proper blood collection technique and awareness of the workload of health care workers are recommended to decrease contamination rates during the COVID-19 pandemic. IMPORTANCE Understanding factors that contribute to blood culture contamination is important in order to take steps to limit contamination events. Here, we examine the effect the COVID-19 pandemic has had on blood culture contamination rates and specifically detail the effects based on the staff, draw types, and unit types. The conclusions provided here can be used as hospitals and laboratories navigate the COVID-19 pandemic or other times of high patient volume.

Initial Specimen Diversion Device® Reduces Blood Culture Contamination and Vancomycin Use in Academic Medical Center

BACKGROUND

In suspected bloodstream infections, accurate blood culture results are critical to timely diagnoses and appropriate antibiotic administration.

AIM

An Initial Specimen Diversion Device®, Steripath®, (Magnolia Medical Technologies, Seattle, WA) was evaluated for efficacy in reducing blood culture contamination at Brooke Army Medical Center (6.8% six-month contamination rate prior to intervention) in a six-month quality improvement project.

METHODS

Blood cultures in the emergency department were collected using either Steripath® or the standard method. 20 mL of blood was cultured into an aerobic and anaerobic medium and incubated for five days using an automated microbial detection system immediately after collection. Positive bottles were Gram stained and plated. Rapid molecular PCR identification was performed on all first positive bottles within a blood culture set for each admission or ED visit. Speciation was deduced during antimicrobial sensitivity testing using the Vitek-2 instrument.

FINDINGS

Seven (7/1016, 0.69%) contamination events occurred when using Steripath® vs. 53 (53/800, 6.6%) contamination events when using the standard method. Steripath® use was associated with a 90% lower incidence of blood culture contamination vs. the standard method. Post-study, Steripath® use was implemented as standard practice hospital-wide, and a retrospective data analysis attributed a 31.4% decrease in vancomycin days of therapy to Steripath® adoption.

CONCLUSION

Using Steripath® significantly decreased blood culture contamination events for bacterial bloodstream infections compared to the standard method. Subsequent adoption of Steripath® reduced overall vancomycin usage. With widescale implementation Steripath® could bolster antibiotic stewardship, mitigating antibiotic resistance caused by unnecessary antibacterial treatments.

Audit and Feedback: An Evidence-Based Practice Literature Review of Nursing Report Cards

BACKGROUND

As more hospitals transition to electronic health records (EHR) and rely on technology to inform practice, what is done with that information is increasingly important. Performance report cards for physicians and nurses are not new, yet there is little recent evidence on nurse-specific audit and feedback.

AIM

The aim of the project was to conduct an evidence-based practice (EBP) review to answer the question, "Does implementing an individualized audit and feedback report tool for nurses improve compliance, adherence, and/or performance of nursing tasks?".

METHODS

Evidence was gathered from several databases. Reviewers read and appraised articles that answered the EBP question using the Johns Hopkins Nursing EBP Model. Data were then collated to synthesize and generate recommendations.

RESULTS

Of the initial 613 unique articles, eight (two research and six quality improvement) were included. Six articles demonstrated improvements while two did not. Articles analyzed nursing documentation (n = 3), tasks or skills (n = 2), and best practice compliance (n = 3). One manuscript utilized an EHR-generated report; all others were completed by hand. Overall, there was not consistent and compelling evidence to support individualized audit and feedback report tools in nursing. However, several themes emerged related to sustainability, timing of feedback, audit, and feedback in the context of quality improvement, and the methods of acquiring and distributing data.

LINKING EVIDENCE TO ACTION

The ubiquity and ease of the EHR make providing automated feedback to nurses tempting, yet it is not supported by the literature. More implementation science research is needed to explore audit and feedback reports in nursing. This article adds to the literature by highlighting a significant lack of consistent and compelling positive results from the well-established quality improvement strategy of audit and feedback in the nursing population. The absence of good data is as telling as its presence.

Reducing Blood Culture Contamination Rates: Experiences of Four Hospital Systems

INTRODUCTION

Blood cultures (BCs) frequently become contaminated during the pre-analytic phase of collection leading to downstream ramifications. We present a summary of performance improvement (PI) interventions provided by four hospital systems and common factors that contributed to decreased blood culture contamination (BCC) rates.

METHODS

Each hospital independently formed a multidisciplinary team and action plan for implementation of their intervention, focusing on the use of educational and training tools. Their goal was to significantly decrease their BCC rates. Pre- and post-intervention data were compared during the sustainment period to determine their success.

RESULTS

All hospitals met their goals of post-intervention BCC rates and with most achieving and sustaining BCC rates ≤ 1.0-2.0%.

CONCLUSION

Our report highlights how four hospitals independently achieved their objective to decrease their BCC rate with the support of a multidisciplinary team. We propose a benchmark for BCC rates of 1.5 to < 2.0% as achievable and sustainable.

Practical Guidance for Clinical Microbiology Laboratories: A Comprehensive Update on the Problem of Blood Culture Contamination and a Discussion of Methods for Addressing the Problem

In this review, we present a comprehensive discussion of matters related to the problem of blood culture contamination. Issues addressed include the scope and magnitude of the problem, the bacteria most often recognized as contaminants, the impact of blood culture contamination on clinical microbiology laboratory function, the economic and clinical ramifications of contamination, and, perhaps most importantly, a systematic discussion of solutions to the problem. We conclude by providing a series of unanswered questions that pertain to this important issue.

The effectiveness of interventions to reduce peripheral blood culture contamination in acute care: a systematic review protocol

BACKGROUND

Blood cultures are an integral part of the diagnosis of bacteremia in unwell patients. The treatment of bacteremia involves the rapid and accurate identification of the causative agent grown from the blood cultures collected. Contamination of blood cultures with non-pathogenic microbes such as skin commensals causes false positive results and subsequent unnecessary and potentially harmful interventions. While guidelines for blood culture quality recommend no more than 2-3% contamination rate, rates up to 12% are reported in the literature. There have been a number of methods proposed to reduce the contamination of blood cultures, including educational interventions, changing of skin cleansing preparations and introduction of blood culture collection packs in acute care settings. This protocol outlines methods to identify and evaluate interventions to reduce blood culture contamination in the acute care setting.

METHODS

The reviewers will conduct a systematic search of literature in CINHAL, PubMed, EMBASE and the Cochrane Central register of controlled trials. Unpublished works will be identified in ProQuest Dissertations and Theses. Articles will be assessed for relevance based on their title and abstract. Remaining relevant citations will have their full text retrieved and assessed against eligibility criteria. All studies that meet the eligibility criteria will have their methodological quality appraised. Assessments for relevance and methodological quality will be conducted independently by two reviewers. If appropriate, data will be analysed using the Mantel-Haenszel method under a random effects model. Heterogeneity of the studies will be assessed using the I 2 and chi-squared statistic. Meta-analysis will be attempted if the data is suitable.

DISCUSSION

This review will identify and summarise the interventions previously described in the literature aimed at reducing peripherally collected blood culture contamination rates in acute care. These findings have the potential to lead to multifaceted interventions based on previous evidence to reduce blood culture contamination in the acute setting. Reductions in the proportion of contaminated blood cultures have the potential to save money, unrequired treatment (particularly antimicrobials) and hospital bed days.

SYSTEMATIC REVIEW REGISTRATION

In accordance with guidelines outlined in the PRISMA-P methodology, this protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) on December 8, 2017, and last updated on January 4, 2018 (registration number CRD42017081650).

A Quality Improvement Initiative: Reducing Blood Culture Contamination in a Children's Hospital

BACKGROUND AND OBJECTIVE

Blood culture contamination is a safety and quality concern in children's hospitals; it leads to increased unnecessary testing, admissions, antibiotic exposure, and cost. The standard benchmark for blood culture contamination is 3%. Our aim with the quality improvement project was to reduce the contamination rate at our children's hospital from a mean of 2.85% to <1.5% in 2 years.

METHODS

After initial unit-specific efforts, we formed a multidisciplinary team, created a process map and a cause-and-effect analysis, sent out surveys to nurses, and created observation sheets used to identify problem areas and record the most common deviations during the collection process. We also standardized the blood culture collection protocol and reemphasized nurse education in person and with online modules. During our project, we noted that nurses were collecting 1 to 3 mL of blood on all children regardless of weight. We developed optimal weight-based blood volumes and, after educating ordering providers, we updated our electronic medical record to reflect appropriate volumes in the order.

RESULTS

Despite a steady increase in the number of blood cultures collected at our children's hospital, we were able to decrease the average contamination rate from 2.85% to 1.54%, saving the hospital an estimated average of $49 998 per month.

CONCLUSIONS

By standardizing blood culture collection methods, optimizing blood volume, creating checklists, and reinforcing nurse education, we were able to develop a best practice for pediatric blood culture collection and reduce blood culture contamination to a sustainable low rate at our children's hospital.

Impact of bacteremia prediction rule in CAP: Before and after study

OBJECTIVE

In cases of community acquired pneumonia (CAP), it has been known that blood cultures have low yields and rarely affect clinical outcomes. Despite many studies predicting the likelihood of bacteremia in CAP patients, those results have been rarely implemented in clinical practice, and use of blood culture in CAP is still increasing. This study evaluated impact of implementing a previously derived and validated bacteremia prediction rule.

METHODS

In this registry-based before and after study, we used piecewise regression analysis to compare the blood culture rate before and after implementation of the prediction rule. We also compared 30-day mortality, emergency department (ED) length of stay, time-interval to initial antibiotics after ED arrival, and any changes to the antibiotics regimen as results of the blood cultures. In subgroup analysis, we compared two groups (with or without the use of the prediction rule) after implementation period, using propensity score matching.

RESULTS

Following the implementation, the blood culture rate declined from 85.5% to 78.1% (P=0.003) without significant changes in 30-day mortality and antibiotics regimen. The interval to initial antibiotics (231min vs. 221min, P=0.362) and length of stay (1019min vs. 954min, P=0.354) were not significantly changed. In subgroup analysis, the group that use the prediction rule showed 25min faster antibiotics initiation (P=0.002) and 48min shorter length of stay (P=0.007) than the group that did not use the rule.

CONCLUSION

Implementation of the bacteremia prediction rule in CAP patients reduced the blood culture rate without affecting the 30-day mortality and antibiotics regimen.

Effect of a training programme on blood culture contamination rate in critical care

Blood culture contamination can occur from extraction to processing; its rate should not exceed 3%.

OBJECTIVE

To evaluate the impact of a training programme on the rate of contaminated blood cultures after the implementation of sample extraction recommendations based on the best evidence.

METHOD

Prospective before-after study in a polyvalent intensive care unit with 18 beds. Two phases were established (January-June 2012, October 2012-October 2015) with a training period between them. Main recommendations: sterile technique, surgical mask, double skin disinfection (70° alcohol and 2% alcoholic chlorhexidine), 70° alcohol disinfection of culture flasks and injection of samples without changing needles. Including all blood cultures of patients with extraction request.

VARIABLES

demographic, severity, pathology, reason for admission, stay and results of blood cultures (negative, positive and contaminated). Basic descriptive statistics: mean (standard deviation), median (interquartile range) and percentage (95% confidence interval). Calculated contamination rates per 100 blood cultures extracted. Bivariate analysis between periods.

RESULTS

Four hundred and eight patients were included. Eight hundred and forty-one blood cultures were taken, 33 of which were contaminated. In the demographic variables, severity, diagnosis and stay of patients with contaminated samples, no differences were observed from those with uncontaminated samples. Pre-training vs post-training contamination rates: 14 vs 5.6 per 100 blood cultures extracted (P=.00003).

CONCLUSION

An evidence-based training programme reduced the contamination of samples. It is necessary to continue working on the planning of activities and care to improve the detection of pollutants and prevent contamination of samples.

The effect of a quality improvement programme reducing blood culture contamination on the detection of bloodstream infection in an emergency department

BACKGROUND

Contaminated blood cultures (BC) generate avoidable costs and prolong hospital stays. To measure our hospital's performance against the recommended standard of <3% BC contamination, we performed a prospective study.

METHODS

We prospectively determined the frequency of contaminated and genuinely positive BC hospital-wide over seven months.

RESULTS

Overall, 73 of 1,829 blood cultures reviewed were contaminated (4.0%). However, distribution of contamination was not uniform. Finding a consistently higher incidence of contamination (11.7%) in our emergency department (ED) than elsewhere in the hospital (2.5%), we adopted a collaborative quality improvement strategy targeted to the ED. A combination of education, modified BC packs and regular feedback of BC results was associated with a significant reduction in contamination (7.4%, p=0.01) over the next six months. Our data suggests that contaminated BC were more likely to have been taken during regular day time hours (odds ratio (OR) 2.7, p=0.012), rather than overnight and were not associated with influxes of new junior medical staff. We found no evidence that the incidence of true bloodstream infection (12.8%) diagnosed by our ED was adversely affected by our intervention (10.7%, p=0.35).

CONCLUSIONS

Using a simple and inexpensive collaborative intervention we reduced BC contamination without adversely affecting the detection of genuine BSI.