Reducing False-Positive Peripheral Blood Cultures in a Pediatric Emergency Department

The Validity of Positive Coagulase-Negative Staphylococcus Cultures for the Diagnosis of Sepsis in the Neonatal Unit

OBJECTIVE

 Coagulase-negative Staphylococcus (CoNS) is the most frequent pathogen causing late-onset sepsis (LOS) in neonatal intensive care units (NICUs). Technical difficulties hinder blood culture (BC) collection and obtaining only one culture before initiating antibiotic therapy is a common practice. We sought to assess specific clinical information and CoNS cultures for the diagnosis of true bacteremia in the NICU.

STUDY DESIGN

 This historical cohort study was conducted in NICUs at the Hadassah-Hebrew University Medical Center of Jerusalem in Israel. Clinical and laboratory data in every CoNS bacteremia were collected and compared between bacteremia groups as follows: true positive, two positive BCs; contaminant, one positive BC out of two; undefined, one BC obtained and found positive.

RESULTS

 For 3.5 years, CoNS was isolated in 139 episodes. True positive was identified in 44 of 139 (31.7%), contaminant in 42 of 139 (30.2%), and the event was undefined in 53 of 139 (38.1%). Vancomycin treatment was more frequent in the true positive and undefined groups than the contaminant group (100, 90.6, and 73.8% respectively, p = 0.001); treatment was also prolonged in these two groups (p < 0.001). No clinical variables were associated with true bacteremia on multivariable analysis.

CONCLUSION

 Diagnosis should definitely be based on at least two positive BCs, despite objective difficulties in obtaining BCs in neonates.

KEY POINTS

· CoNS is a frequent pathogen causing LOS in neonates.. · Due to technical difficulties, often only one culture is collected prior to antibiotic therapy.. · No clinical/laboratory variables were associated with the diagnosis of true CoNS bacteremia..

The Effects of Moral Distress on Resilience in Pediatric Emergency Department Nurses

INTRODUCTION

Moral distress is widespread in health care, and nurses working in high-pressure environments, such as emergency departments, experience stress at high rates. Understanding how moral distress affects pediatric emergency nursing care is essential to moderate its negative impacts. Increased resilience has been promoted as a tool to mitigate moral distress. The purpose of this study, conducted prior to the pandemic, was to examine patterns of moral distress and the impact of moral distress on resilience among pediatric emergency nurses.

METHODS

A cross-sectional exploratory study of pediatric emergency nurses was performed. Moral Distress Scale-Revised (Pediatric) and Connor-Davidson Resilience Scale 25© scores were collected and calculated. Exploratory factor analysis with principal components was used to identify patterns of moral distress that impact resilience.

RESULTS

Four distinct patterns of moral distress that impact resilience were identified: (1) incompetent practice, (2) incongruent truth-telling, (3) potentially inappropriate care, and (4) discordant health care teams.

DISCUSSION

Our study was the first to identify 4 patterns of moral distress in pediatric emergency nurses. As a result, actions to promote resilience include: (1) supporting competent practice, (2) upholding appropriate truth-telling, (3) recognizing and addressing potentially inappropriate care, and (4) building concordant health care teams and systems. This pre-pandemic data provides a foundational understanding of the relationship between moral distress and resilience in pediatric emergency nurses. Identifying factors of moral distress that impact resilience has significant implications for pediatric emergency nursing, including the development of future initiatives, education, and research.

Reporting and Categorization of Blood Culture Contaminants in Infants and Young Children: A Scoping Review

BACKGROUND

Blood cultures are obtained routinely for infants and young children for the evaluation for serious bacterial infection. Isolation of organisms that represent possible contaminants poses a management challenge. The prevalence of bacteremia reported in this population is potentially biased by inconsistent contaminant categorization reported in the literature. Our aim was to systematically review the definition and reporting of contaminants within the literature regarding infant bacteremia.

METHODS

A search of studies published between 1986 and mid-September 2016 was conducted using Medline/PubMed. Included studies examined children aged 0 to 36 months for whom blood culture was performed as part of a serious bacterial infection evaluation. Studies that involved children in an intensive care unit, prematurely born children, and immunocompromised children or those with an indwelling catheter/device were excluded. Data extracted included contaminant designation methodology, organisms classified as contaminants and pathogens, and contamination and bacteremia rates.

DISCUSSION

Our search yielded 1335 articles, and 69 of them met our inclusion criteria. The methodology used to define contaminants was described in 37 (54%) study reports, and 16 (23%) reported contamination rates, which ranged from 0.5% to 22.8%. Studies defined contaminants according to organism species (n = 22), according to the patient's clinical management (n = 4), and using multifactorial approaches (n = 11). Many common organisms, particularly Gram-positive cocci, were inconsistently categorized as pathogens or contaminants.

CONCLUSIONS

Reporting and categorization of blood culture contamination are inconsistent within the pediatric bacteremia literature, which limits our ability to estimate the prevalence of bacteremia. Although contaminants are characterized most frequently according to organism, we found inconsistency regarding the classification of certain common organisms. A standardized approach to contaminant reporting is needed.

Skin preparation for prevention of peripheral blood culture contamination in children

BACKGROUND

In Japan, blood cultures for children are performed by pediatric residents, and povidone-iodine (PI) is the recommended solution for skin preparation. Given that PI needs to be applied for 1.5-2 min before venipuncture, skin preparation may be suboptimal if this is not followed. In this study, we investigated the blood culture contamination rate after skin preparation with only 70% isopropyl alcohol (IPA) or IPA plus PI.

METHODS

We performed a retrospective study of patients aged ≤6 years who provided blood cultures in the emergency department or pediatric ward. Patients with indwelling central venous catheter were excluded. We evaluated the impact of changing the method of skin preparation, comparing the traditional method using IPA plus PI between 2008 and 2010 (IPA + PI group) with the simplified method using only IPA between 2015 and 2017 (IPA group).

RESULTS

A total of 5,365 blood culture samples were eligible for this study. Of these, 171 (3.2%) had an organism identified in blood culture. Of the blood culture-positive samples, 68 (1.3%) were true positive and 103 (1.9%) were contaminated. Thirty-eight (1.6%) of 2,407 cultures in the IPA group were contaminated, whereas 65 (2.2%) of 2,958 cultures in the IPA + PI group were contaminated (OR, 0.72; 95%CI: 0.48-1.07; P = 0.1). Coagulase-negative Staphylococcus grew significantly less in the IPA group (1.7% vs 1.0%, P = 0.02).

CONCLUSIONS

A single application of 70% IPA may be the optimal skin preparation method for obtaining peripheral blood cultures from children in Japan.

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).

Decreasing Blood Culture Contaminants in a Pediatric Emergency Department: An Interrupted Time Series Analysis

INTRODUCTION

High peripheral blood culture contamination rates (BCCR) in the emergency department (ED) contribute to overuse and harm. This study describes 2 years of quality improvement (QI) interventions that aimed to decrease a high BCCR in a pediatric ED.

METHODS

The QI team created a Key Driver Diagram with multiple Plan-Do-Study-Act (PDSA) cycles. PDSA interventions included a venipuncture sterility checklist (PDSA1), phlebotomist feedback system (PDSA2), and physician ordering guidelines (PDSA3). The specific aim was to decrease the BCCR by 50% within 24 months. The secondary aim was to decrease the peripheral blood culture ordering rate (BCOR) by 10% within 24 months. The balancing measure was the proportion of pathogenic bacteremia cases at ED return visits before and after PDSA3 implementation. A financial measure estimated the savings in charges between the observed and expected contaminants in PDSA3. An interrupted time series design applied statistical process control methodology to detect special cause variations.

RESULTS

The BCCR in the baseline, PDSA1, PDSA2, and PDSA3 periods were 3.02%, 2.30%, 1.58%, and 1.17%, respectively. The BCOR in the baseline, PDSA1, PDSA2, and PDSA3 periods was 4.80%, 4.26%, 3.82%, and 3.49%, respectively. Special cause variations occurred after PDSA cycle implementations for both BCCR and BCOR. There was no change in the balancing measure. The interventions were associated with an annual prevention of 95 contaminants and savings of $300,070.

CONCLUSIONS

Interventions that focused on improving venipuncture technique and limiting unnecessary blood cultures were associated with fewer contaminants and the achievement of the QI team's project aims.

Adverse Economic Impact Associated With Blood Culture Contamination in a Pediatric Emergency Department

BACKGROUND

Blood culture contamination (BCC) leads to unnecessary interventions including hospitalization, antibiotic administration and additional laboratory tests. Previous studies in adults revealed that BCC was associated with unnecessary financial expenditures. However, information pertaining to the pediatric population is limited. Therefore, we investigated the details of the adverse economic impact associated with BCC in a pediatric emergency department (ED) in Japan.

METHODS

This study was a retrospective, observational study. We collected data on blood cultures performed in patients 18 years of age in a pediatric ED. Medical records of patients with positive blood cultures were reviewed, and the information regarding adverse events related to BCC was extracted. Medical costs related to BCC were estimated from the data.

RESULTS

In total, 13,139 sets of blood cultures were performed from April 2013 to June 2016, and 141 cases (1.1%) of BCC were identified. Among these, 106 patients (75%) experienced at least 1 adverse event associated with BCC. The total medical cost due to BCC was 4,076,713 Japanese yen. Multifaceted approaches targeting ED physicians including lectures on optimal blood collection methods and monthly feedback on BCC rates were effective in reducing the BCC rate and its related costs.

CONCLUSIONS

Interventions associated with BCC were common and accounted for significant adverse economic impact on pediatric patients. Regular education and monitoring were effective in reducing BCC and its related costs.

Using anaerobic blood cultures for infants younger than 90 days rarely showed anaerobic infections but increased yields of bacterial growth

AIM

The use of anaerobic blood cultures in infants suspected of bacteraemia is controversial. Our children's hospital uses both aerobic and anaerobic media, regardless of the risk of anaerobic infection, and the aim of this study was to re-evaluate the use of anaerobic cultures in infants.

METHODS

We collected retrospective data from 2002 to 2016 on all blood cultures taken from infants younger than 90 days in the Hadassah-Hebrew University Medical Centre, Jerusalem, Israel. The incidence and characteristics of infants with positive anaerobic blood cultures were assessed.

RESULTS

During the study period, 51 035 blood cultures were drawn from 44 304 infants. Of these, 1496 (2.9%) were clinically significant positive cultures. Pathogenic obligatory anaerobic bacteraemia was extremely rare, with only 37 positive cultures (0.07%) from all of the cultures drawn. No specific risk factors for obligatory anaerobic bacteraemia could be defined, but as many as 174 (11.6%) clinically significant isolates were only detected in the anaerobic culture bottle.

CONCLUSION

True anaerobic bacteraemia was extremely rare in neonates. Nevertheless, using anaerobic culture media may increase the overall yield of bacterial culture growth by isolating anaerobic-facultative bacteria. This should be weighed up against increasing the volume of blood used for the aerobic culture.

Yield of Anaerobic Blood Cultures in Pediatric Emergency Department Patients

BACKGROUND

Anaerobic bacteremia is rare in children and current recommendations advocate against the routine use of anaerobic cultures in children. However, the incidence of anaerobic bacteremia and the utility of anaerobic blood cultures in children have not been assessed in recent years. Our pediatric emergency department (PED) policy still supports the use of both aerobic and anaerobic blood cultures in all cases of suspected bacteremia. This allowed us to re-evaluate the yield of anaerobic cultures in PED settings.

METHODS

Retrospective data of all blood cultures taken in the PED in a single tertiary center from 2002 to 2016 were collected. The incidence and characteristics of children with positive anaerobic blood cultures were assessed. Risk factors for anaerobic bacteremia were defined.

RESULTS

Of the 68,304 blood culture sets taken during the study period, 971 (1.42%) clinically significant positive cultures were found. Pathogenic obligatory anaerobic bacteria were isolated in 33 (0.05%) cultures. The leading risk factors for anaerobic bacteremia were head and neck abscess and intra-abdominal infection. Of all the true positive cultures, 187 (22%) were only detected in the anaerobic culture and would have otherwise been missed.

CONCLUSIONS

True anaerobic bacteremia is extremely rare in children admitted to the PED. Nevertheless, using anaerobic cultures may increase the overall yield of blood cultures.

Quality in paediatric emergency medicine: Measurement and reporting

There is a clear demand for quality in the delivery of health care around the world; paediatric emergency medicine is no exception to this movement. It has been identified that gaps exist in the quality of acute care provided to children. Regulatory bodies in Australia and New Zealand are moving to mandate the implementation of quality targets and measures. Within the paediatric emergency department (ED), there is a lack of research into paediatric specific indicators. The existing literature regarding paediatric acute care quality measures has been recently summarised, and expert consensus has now been reported. It is clear that there is much work to be performed to generalise this work to ED. We review suggestions from the current literature relating to feasible indicators within the paediatric acute care setting. We propose options to develop a quality 'scorecard' that could be used to assist Australian and New Zealand EDs with quality measurement and benchmarking for their paediatric patients.

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.

Blood culture contamination in hospitalized pediatric patients: a single institution experience

PURPOSE

Blood culture is the most important tool for detecting bacteremia in children with fever. However, blood culture contamination rates range from 0.6% to 6.0% in adults; rates for young children have been considered higher than these, although data are limited, especially in Korea. This study determined the contamination rate and risk factors in pediatric patients visiting the emergency room (ER) or being admitted to the ward.

METHODS

We conducted a retrospective chart review of blood cultures obtained from children who visited Yonsei Severance Hospital, Korea between 2006 and 2010. Positive blood cultures were labeled as true bacteremia or contamination according to Centers for Disease Control and Prevention/National Healthcare Safety Network definitions for laboratory-confirmed bloodstream infection, after exclusion of cultures drawn from preexisting central lines only.

RESULTS

Among 40,542 blood cultures, 610 were positive, of which 479 were contaminations and 131 were true bacteremia (overall contamination rate, 1.18%). The contamination rate in the ER was significantly higher than in the ward (1.32% vs. 0.66%, P<0.001). The rate was higher in younger children (2.07%, 0.94%, and 0.61% in children aged <1 year, 1-6 years, and >6 years, respectively).

CONCLUSION

Overall, contamination rates were higher in younger children than in older children, given the difficulty of performing blood sampling in younger children. The contamination rates from the ER were higher than those from the ward, not accounted for only by overcrowding and lack of experience among personnel collecting samples. Further study to investigate other factors affecting contamination should be required.

Reducing blood culture contamination rates in the emergency department

INTRODUCTION

Routine monthly monitoring of blood culture (BC) contamination rates detected a spike (>3%) in false-positive BCs drawn in the emergency department. This triggered an ad hoc quality-improvement team to develop and implement a corrective action plan in our 230-bed urban community hospital with 58,000 ED visits annually.

METHODS

Both phlebotomists and nurses draw BCs in the emergency department; therefore all interventions were directed at both groups. These included private conversations with individual staff members associated with higher numbers of contaminated draws compared with peers, ensuring availability of necessary BC collection supplies, re-education of all phlebotomists and ED nursing staff surrounding BC collection best practices, monthly feedback to staff on BC contamination rates, and continuing private conversations as necessary, regardless of the contamination rate.

RESULTS

Before the spike in the emergency department, the average rate of BC contamination for the hospital as a whole was 1.82% (January-July 2011). Excluding 3 months when ED contamination was greater than 3% and the hospital contamination rate was 2.65% (August-October 2011), the average rate of BC contamination for the hospital dropped to 1.01% after the interventions (November 2011-June 2012). This represents a 44% decrease moving from 1.82% to 1.01% in hospital-wide BC contamination rates and an annualized cost avoidance of approximately $614,000.

DISCUSSION

The ED BC contamination rate spike occurred over a 3-month period during which the emergency department was transitioning into a new facility on the same campus. The total hospital BC contamination rate never rose above the 3% benchmark, which illustrates the importance of tracking ED-specific data.