Regression discontinuity of blood culture contamination rate after changing of disinfectants: retrospective observational study

AbstractBlood cultures are indispensable for detecting life-threatening bacteremia. Little is known about associations between contamination rates and topical disinfectants for blood collection in adults. We sought to determine whether a change in topical disinfectants was associated with the rates of contaminated blood cultures in the emergency department of a single institution. This single-center, retrospective observational study of consecutive patients aged 20 years or older was conducted in the emergency department (ED) of a university hospital in Japan between August 1, 2018 and September 30, 2020. Pairs of blood samples were collected for aerobic and anaerobic culture from the patients in the ED. Physicians selected topical disinfectants according to their personal preference before September 1, 2019; alcohol/chlorhexidine gluconate (ACHX) was mandatory thereafter, unless the patient was allergic to alcohol. Regression discontinuity analysis was used to detect the effect of the mandatory usage of ACHX on rates of contaminated blood cultures. We collected 2141 blood culture samples from 1097 patients and found 164 (7.7%) potentially contaminated blood cultures. Among these, 445 (20.8%) were true bacteremia and 1532 (71.6%) were true negatives. Puncture site disinfection was performed with ACHX for 1345 (62.8%) cases and with povidone-iodine (PVI) for 767 (35.8%) cases. The regression discontinuity analysis showed that mandatory ACHX usage was significantly associated with lower rates of contaminated blood cultures by 9.6% (95% confidence interval (CI): 5.0%–14.2%, P < 0.001). Rates of contaminated blood cultures were significantly lower when ACHX was used as the topical disinfectant.

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Regression Discontinuity of Blood Culture Contamination Rate After Changing of Disinfectants: Retrospective Observational Study

10.21203/rs.3.rs-754189/v1 ◽

2021 ◽

Author(s):

Koshi Ota ◽

Daisuke Nishioka ◽

Yuri Ito ◽

Emi Hamada ◽

Naomi Mori ◽

...

Keyword(s):

Emergency Department ◽

Blood Culture ◽

Observational Study ◽

Regression Discontinuity ◽

Blood Cultures ◽

University Hospital ◽

Retrospective Observational Study ◽

Contamination Rate ◽

Blood Collection ◽

Contaminated Blood

Abstract Background: Blood cultures are indispensable for detecting life-threatening bacteremia. Little is known about associations between contamination rates and topical disinfectants for blood collection in adults.Objective: We sought to determine whether a change in topical disinfectants was associated with the rates of contaminated blood cultures in the emergency department of a single institution.Methods: This single-center, retrospective observational study of consecutive patients aged 20 years or older was conducted in the emergency department (ED) of a university hospital in Japan between August 1, 2018 and September 30, 2020. Pairs of blood samples were collected for aerobic and anaerobic culture from the patients in the ED. Physicians selected topical disinfectants according to their personal preference before September 1, 2019; alcohol/chlorhexidine gluconate (ACHX) was mandatory thereafter, unless the patient was allergic to alcohol. Regression discontinuity analysis was used to detect the effect of the mandatory usage of ACHX on rates of contaminated blood cultures.Results: We collected 2,141 blood culture samples from 1097 patients and found 164 (7.7%) potentially contaminated blood cultures. Among these, 445 (20.8%) were true bacteremia and 1,532 (71.6%) were true negatives. Puncture site disinfection was performed with ACHX for 1,345 (62.8%) cases and with povidone-iodine (PVI) for 767 (35.8%) cases. The regression discontinuity analysis showed that mandatory ACHX usage significantly reduced the blood culture contamination rate by 9.6% (95% confidence interval (CI): 5.0%–14.2%, P <0.001).Conclusion: Rates of contaminated blood cultures were significantly lower when ACHX was used as the topical disinfectant.

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Regression Discontinuity of Blood Culture Contamination Rate After Changing of Disinfectants: Retrospective Observational Study

SSRN Electronic Journal ◽

10.2139/ssrn.3792346 ◽

2021 ◽

Author(s):

Koshi Ota ◽

Daisuke Nishioka ◽

Yuri Ito ◽

Emi Hamada ◽

Naomi Mori ◽

...

Keyword(s):

Blood Culture ◽

Observational Study ◽

Regression Discontinuity ◽

Retrospective Observational Study ◽

Contamination Rate

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Sites of blood collection and topical antiseptics associated with contaminated cultures: prospective observational study

Scientific Reports ◽

10.1038/s41598-021-85614-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Koshi Ota ◽

Koji Oba ◽

Keisuke Fukui ◽

Yuri Ito ◽

Emi Hamada ◽

...

Keyword(s):

Observational Study ◽

Prospective Observational Study ◽

Povidone Iodine ◽

Risk Difference ◽

Blood Cultures ◽

University Hospital ◽

Blood Collection ◽

Adjusted Risk ◽

Contaminated Blood ◽

Aerobic And Anaerobic

AbstractWe aimed to determine whether puncture sites for blood sampling and topical disinfectants are associated with rates of contaminated blood cultures in the emergency department (ED) of a single institution. This single-center, prospective observational study of 249 consecutive patients aged ≥ 20 years proceeded in the ED of a university hospital in Japan during 6 months. Pairs of blood samples were collected for aerobic and anaerobic culture from all patients in the ED. Physicians selected puncture sites and topical disinfectants according to their personal preference. We found 50 (20.1%) patients with potentially contaminated blood cultures. Fifty-six (22.5%) patients were true bacteremia and 143 (57.4%) patients were true negatives. Multivariate analysis associated more frequent contamination when puncture sites were disinfected with povidone-iodine than with alcohol/chlorhexidine (adjusted risk difference, 12.9%; 95% confidence interval [CI] 8.8–16.9; P < 0.001). Sites of blood collection were also associated with contamination. Femoral and central venous with other sites were associated with contamination more frequently than venous sites (adjusted risk difference), 13.1% (95% CI 8.2–17.9; P < 0.001]) vs. 17.3% (95% CI 3.6–31.0; P = 0.013). Rates of contaminated blood cultures were significantly higher when blood was collected from femoral sites and when povidone-iodine was the topical antiseptic.

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Comparison of the Contamination Rate and Risk Factor Profile of Blood Culture Done in Emergency Department and MHDU/MICUs

Global Journal of Medical Research ◽

10.34257/mrcvol21is2pg1 ◽

2021 ◽

pp. 1-8

Author(s):

Dr. Pankaj Kumar Singh

Keyword(s):

Risk Factors ◽

Emergency Department ◽

Risk Factor ◽

Blood Culture ◽

Observational Study ◽

Prospective Observational Study ◽

Contamination Rate ◽

Medical Illness ◽

Inclusion Criteria ◽

Factors Associated

Aims and objectives: To determine the risk factors of blood culture contamination done in ED and those done in the MHDU/MICU among patients admitted with medical illness. Material and Methods: This is a two months’ prospective observational study comparing blood culture contamination rate and risk factors associated with contamination between ED and MICU/MHDU. A total of 998 patients were included in the study who underwent blood culture in ED and MICU/MHDU. 570 in ED and 428 in MICU/MHDU were included after meeting exclusion and inclusion criteria. Results: Blood culture growths were higher in ED (19%). Most common growth was CoNS (4%). The overall contamination rate in this study was (4.8%) The contamination rate was lower in ED (4.4%) when compared to MICU/MHDU (5.4%).

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Evaluation of an Initial Specimen Diversion Device (ISDD) on Rates of Blood Culture Contamination in the Emergency Department

Kansas Journal of Medicine ◽

10.17161/kjm.vol1413804 ◽

2021 ◽

Vol 14 ◽

pp. 73-76

Author(s):

Blake Buzard ◽

Patrick Evans ◽

Todd Schroeder

Keyword(s):

Emergency Department ◽

Length Of Stay ◽

Blood Culture ◽

Blood Cultures ◽

Contamination Rate ◽

Total Hospital Cost ◽

Initial Specimen ◽

Significant Difference ◽

Secondary Outcomes ◽

The Impact

Introduction: Blood cultures are the gold standard for identifying bloodstream infections. The Clinical and Laboratory Standards Institute recommends a blood culture contamination rate of <3%. Contamination can lead to misdiagnosis, increased length of stay and hospital costs, unnecessary testing and antibiotic use. These reasons led to the development of initial specimen diversion devices (ISDD). The purpose of this study is to evaluate the impact of an initial specimen diversion device on rates of blood culture contamination in the emergency department. Methods: This was a retrospective, multi-site study including patients who had blood cultures drawn in an emergency department. February 2018 to April 2018, when an ISDD was not utilized, was compared with June 2019 to August 2019, a period where an ISDD was being used. The primary outcome was total blood culture contamination. Secondary outcomes were total hospital cost, hospital and intensive care unit length of stay, vancomycin days of use, vancomycin serum concentrations obtained, and repeat blood cultures obtained. Results: A statistically significant difference was found in blood culture contamination rates in the Pre-ISDD group vs the ISDD group (7.47% vs 2.59%, p<0.001). None of the secondary endpoints showed a statistically significant difference. Conclusions: Implementation of an ISDD reduces blood culture contamination in a statistically significant manner. However, we were unable to capture any statistically significant differences in the secondary outcomes.

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660. Effect of the COVID-19 Pandemic on Blood Culture Contamination Rates and Quality Improvement Processes

Open Forum Infectious Diseases ◽

10.1093/ofid/ofab466.857 ◽

2021 ◽

Vol 8 (Supplement_1) ◽

pp. S432-S432

Author(s):

Alexander G Hosse

Keyword(s):

Emergency Department ◽

Blood Culture ◽

Nursing Staff ◽

Blood Cultures ◽

Hospital Length Of Stay ◽

Contamination Rate ◽

Culture Collections ◽

Total Blood ◽

Primary Driver ◽

Inpatient Units

Abstract Background Blood cultures are the gold standard for diagnosing bloodstream infections and a vital part of the work-up in systemic infections. However, contamination of blood cultures represents a significant burden on patients and the healthcare system with increased hospital length of stay, unnecessary antibiotics, and financial cost. The data discussed here offer insight into blood culture contamination rates before and through the COVID-19 pandemic at a community hospital and the processes that were affected by the pandemic. Methods Blood culture contaminations were determined by using the number of sets of blood cultures with growth and the presence of an organism from the National Healthcare Safety Network's (NHSN) commensal organism. Contamination rates were evaluated by status as a standard unit or a COVID-19 isolation unit in either the emergency department (ED) or inpatient floor units. The identified four groups had different processes for drawing blood cultures, particularly in terms of training of staff in use of diversion devices. The electronic medical record was used to track contaminations and the use of diversion devices in the different units. Results The inpatient COVID units were consistently elevated above the other units and the institutional contaminant goal of 2.25%, ranging from 9.6% to 13.3% from 4/2020-9/2020. Those units were the primary driver of the increase in overall contamination rates. COVID ED nursing staff (that had previously undergone training in the use of diversion devices) used diversion devices to draw 51 of 133 (38.3%) cultures compared to only 15 of 84 (17.9%) on the COVID inpatient units. Figure 1. Comparison of contamination rates in the ED vs the inpatient units from all campuses from September 2019 through September 2020. The blue line represents the hospital goal of 2.25% contamination rate. Solid lines represent total contamination rates including COVID isolation units whereas dotted lines represent units excluding COVID isolation units. Figure 2. Comparison of the non-COVID vs COVID isolation units in the emergency department and inpatient units. The red line represents the hospital goal of less than 2.25% for blood culture contamination rate. Table of Contaminants vs. Total Collected Blood Cultures in Each Unit by Month Figure 3. Raw data from Figure 2. Total blood culture contaminations from each unit by month compared to total blood culture collections from each unit by month. Conclusion Evaluation revealed that nursing staff with less training in blood culture collection, particularly the use of diversion devices, were the primary staff collecting blood cultures in the inpatient COVID units. The difference in training is felt to be the primary driver of the increase in contaminants in the inpatient COVID units. The marked increase in contaminations highlights the difficulties of maintaining quality control processes during an evolving pandemic and the importance of ongoing efforts to improve the quality of care. These findings demonstrate the importance of training and routine use of procedures to reduce contaminations even during. Disclosures All Authors: No reported disclosures

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G-control Charts for Contamination Rates of Blood Cultures in a University Hospital

Siriraj Medical Journal ◽

10.33192/smj.2021.54 ◽

2021 ◽

Vol 73 (6) ◽

pp. 406-412

Author(s):

Tharntip Sangsuwan ◽

Rungtip Darayon ◽

Silom Jamulitrat

Keyword(s):

Blood Culture ◽

Control Charts ◽

Blood Cultures ◽

University Hospital ◽

Contamination Rate ◽

Control And Prevention ◽

Bacillus Spp ◽

Neonatal Icu ◽

Pediatric Icu ◽

Contamination Events

Objective: To determine blood culture contamination rates, and display with a g-chart.Materials and Methods: The medical records of patients, from whom blood cultures were obtained in a university hospital, during January and December 2019 were retrieved and reviewed for contamination. The Center for Disease Control and Prevention (CDC) criteria were used to classify the blood culture results. The contamination rates were illustrated with a g-chart.Results: We identified 331 false-positive blood cultures, among 32,961 cultured specimens; yielding a contamination rate of 1.0% (95%CI = 0.9% – 1.1%). The highest contamination events occurred in the Emergency department (49.2%), Pediatric ICU (5.2%) and Neonatal ICU (4.8%), respectively. The most common commensal bacterial genus were Staphylococcus coagulase negative (67.1%), Bacillus spp. (10.2%) and Corynebacterium spp. (7.6%), correspondingly. The g-charts could identify 14 abnormal variations, in 41 locations.Conclusion: The contamination rates found were within ranges of other reports. G-charts are simple to construct, easy to interpret and sensitive for detection of real time epidemics.

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Diversion Principle Reduces Skin Flora Contamination Rates in a Community Hospital

Archives of Pathology & Laboratory Medicine ◽

10.5858/arpa.2018-0524-oa ◽

2019 ◽

Vol 144 (2) ◽

pp. 215-220 ◽

Cited By ~ 1

Author(s):

Sadia Syed ◽

David T. Liss ◽

Chris O. Costas ◽

Janis M. Atkinson

Keyword(s):

Emergency Department ◽

Blood Culture ◽

Community Hospital ◽

Blood Cultures ◽

Contamination Rate ◽

Significant Cost ◽

Intervention Phase ◽

Medical Centers ◽

Protocol Group ◽

Skin Flora

Context.— Blood culture contamination is a common problem faced by medical centers and leads to significant cost. A possible method to reduce contamination is to discard the initial aliquot of blood, which contains skin and bacteria. Objective.— To determine whether the rate of contaminant blood cultures could be reduced by changing the order of draw to divert the first 7 mL to a gold- or green-top tube. Design.— A preintervention and postintervention study was conducted. During the 18-month intervention phase (September 2015–February 2017), all nurses in the emergency department and inpatient floor phlebotomists collected blood cultures by drawing the first 7 mL of blood into a gold- or green-top tube followed by drawing blood for blood culture bottles. The 18 months immediately preceding the study period (February 2014–July 2015) were used for comparison. Results.— There was an overall statistically significant decrease in contamination rate from 2.46% in the prediversion protocol group to 1.70% in the postdiversion protocol group (P < .001). Emergency department drawn cultures and inpatient cultures showed significant decrease in contamination rates between the preprotocol and postprotocol groups, 2.92% versus 1.95% (P < .001) for emergency department, and 1.82% versus 1.31% (P = .03) for inpatient. We noted less month-to-month variation during the study period compared with the preintervention period. Conclusions.— By using this simple diversion method, we were able to improve blood culture contamination rates for our emergency department and inpatients while incurring no added cost to the procedure.

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Blood Culture Contamination A Randomized Trial Evaluating the Comparative Effectiveness of 3 Skin Antiseptic Interventions

Infection Control and Hospital Epidemiology ◽

10.1086/668777 ◽

2013 ◽

Vol 34 (1) ◽

pp. 15-21 ◽

Cited By ~ 30

Author(s):

Laraine L. Washer ◽

Carol Chenoweth ◽

Hae-Won Kim ◽

Mary A. M. Rogers ◽

Anurag N. Malani ◽

...

Keyword(s):

Blood Culture ◽

Peripheral Blood ◽

Culture Collection ◽

Blood Cultures ◽

Contamination Rate ◽

Peripheral Blood Culture ◽

Skin Antisepsis ◽

Intent To Treat ◽

Random Crossover ◽

Contaminated Blood

Objective.To determine relative rates of blood culture contamination for 3 skin antisepsis interventions—10% povidone iodine aqueous solution (PI), 2% iodine tincture (IT), and 2% Chlorhexidine gluconate in 70% isopropyl alcohol (CHG)—when used by dedicated phlebotomy teams to obtain peripheral blood cultures.Design.Randomized crossover trial with hospital floor as the unit of randomization.Setting.Teaching hospital with 885 beds.Patients.All adult patients undergoing peripheral blood culture collection on 3 medical-surgical floors from May 2009 through September 2009.Intervention.Each antisepsis intervention was used for 5 months on each study floor, with random crossover after a 1-month washout period. Phlebotomy teams collected all peripheral blood cultures. Each positive blood culture was adjudicated by physicians blinded to the intervention and scored as a true positive or contaminated blood culture. The primary outcome was the rate of blood culture contamination for each antisepsis agent.Results.In total, 12,904 peripheral blood culture sets were evaluated, of which 735 (5.7%) were positive. There were 98 contaminated cultures, representing 13.3% of all positive cultures. The overall blood culture contamination rate for the study population was 0.76%. Intent-to-treat rates of contaminated blood cultures were not significantly different among the 3 antiseptics (P = .18), yielding 0.58% with PI (95% confidence interval [CI], 0.38%-0.86%), 0.76% with IT (95% CI, 0.52%-1.07%), and 0.93% with CHG (95% CI, 0.67%-1.27%).Conclusion.Choice of antiseptic agent does not impact contamination rates when blood cultures are obtained by a phlebotomy team and should, therefore, be based on costs or preference.Trial Registration.ClinicalTrials.gov identifier: NCT01216761.

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