PRAISE: providing a roadmap for automated infection surveillance in Europe

INTRODUCTION

Healthcare-associated infections (HAI) are among the most common adverse events of medical care. Surveillance of HAI is a key component of successful infection prevention programmes. Conventional surveillance - manual chart review - is resource intensive and limited by concerns regarding interrater reliability. This has led to the development and use of automated surveillance (AS). Many AS systems are the product of in-house development efforts and heterogeneous in their design and methods. With this roadmap, the PRAISE network aims to provide guidance on how to move AS from the research setting to large-scale implementation, and how to ensure the delivery of surveillance data that are uniform and useful for improvement of quality of care.

METHODS

The PRAISE network brings together 30 experts from ten European countries. This roadmap is based on the outcome of two workshops, teleconference meetings and review by an independent panel of international experts.

RESULTS

This roadmap focuses on the surveillance of HAI within networks of healthcare facilities for the purpose of comparison, prevention and quality improvement initiatives. The roadmap does the following: discusses the selection of surveillance targets, different organizational and methodologic approaches and their advantages, disadvantages and risks; defines key performance requirements of AS systems and suggestions for their design; provides guidance on successful implementation and maintenance; and discusses areas of future research and training requirements for the infection prevention and related disciplines. The roadmap is supported by accompanying documents regarding the governance and information technology aspects of implementing AS.

CONCLUSIONS

Large-scale implementation of AS requires guidance and coordination within and across surveillance networks. Transitions to large-scale AS entail redevelopment of surveillance methods and their interpretation, intensive dialogue with stakeholders and the investment of considerable resources. This roadmap can be used to guide future steps towards implementation, including designing solutions for AS and practical guidance checklists.

A systematic review of central-line-associated bloodstream infection (CLABSI) diagnostic reliability and error

OBJECTIVE

To establish the reliability of the application of National Health and Safety Network (NHSN) central-line-associated bloodstream infection (CLABSI) criteria within established reporting systems internationally.

DESIGN

Diagnostic-test accuracy systematic review.

METHODS

We conducted a search of Medline, SCOPUS, the Cochrane Library, CINAHL (EbscoHost), and PubMed (NCBI). Cohort studies were eligible for inclusion if they compared publicly reported CLABSI rates and were conducted by independent and expertly trained reviewers using NHSN/Centers for Disease Control (or equivalent) criteria. Two independent reviewers screened, extracted data, and assessed risk of bias using the QUADAS 2 tool. Sensitivity, specificity, negative and positive predictive values were analyzed.

RESULTS

A systematic search identified 1,259 publications; 9 studies were eligible for inclusion (n = 7,160 central lines). Publicly reported CLABSI rates were more likely to be underestimated (7 studies) than overestimated (2 studies). Specificity ranged from 0.70 (95% confidence interval [CI], 0.58-0.81) to 0.99 (95% CI, 0.99-1.00) and sensitivity ranged from 0.42 (95% CI, 0.15-0.72) to 0.88 (95% CI, 0.77-0.95). Four studies, which included a consecutive series of patients (whole cohort), reported CLABSI incidence between 9.8% and 20.9%, and absolute CLABSI rates were underestimated by 3.3%-4.4%. The risk of bias was low to moderate in most included studies.

CONCLUSIONS

Our findings suggest consistent underestimation of true CLABSI incidence within publicly reported rates, weakening the validity and reliability of surveillance measures. Auditing, education, and adequate resource allocation is necessary to ensure that surveillance data are accurate and suitable for benchmarking and quality improvement measures over time.

REGISTRATION

Prospectively registered with International prospective register of systematic reviews (PROSPERO ID CRD42015021989; June 7, 2015). https://www.crd.york.ac.uk/PROSPERO/display_record.php?ID%3dCRD42015021989.

Volume-based feeding improves nutritional adequacy in surgical patients

BACKGROUND

Critically ill surgical patients often receive inadequate enteral nutrition using traditional rate-based feeding methods. An alternative strategy is volume-based feeding, in which feeding rates are adjusted to deliver a goal volume per day.

METHODS

This prospective quality improvement study in a single surgical, trauma, and burn ICU compared volume-based feeding to rate-based feeding in a before-and-after design. Outcomes included calories and protein delivered, length of stay, infection, and mortality.

RESULTS

A total of 50 patients received volume-based feeding and 49 rate-based feeding. The volume-based group received a higher proportion of goal calories (84.5% vs. 73.4%; p = 0.005) and protein (86.2% vs. 77.4%; p = 0.01), as well as increased total daily calories (1604 vs. 1356 kcal; p = 0.02). There was no difference in length of stay, mortality, aspiration, or gastrointestinal intolerance.

CONCLUSIONS

Volume-based feeding improved nutritional intake in critically ill surgical patients, although this study was underpowered to determine differences in clinical outcomes.

Ventilator-Associated Pneumonia in Critically Ill Children: A New Paradigm

Ventilator-associated pneumonia (VAP) is a serious complication of critical illness. Surveillance definitions have undergone revisions for more objective and consistent reporting. The 1 organism-1 disease paradigm for microbial involvement may not adequately apply to many cases of VAP, in which pathogens are introduced to a pre-existing and often complex microbial community that facilitates or hinders the potential pathogen, consequently determining whether progression to VAP occurs. As omics technology is applied to VAP, a paradigm is emerging incorporating simultaneous assessments of microbial populations and their activity, as well as the host response, to personalize prevention and treatment.

Validation of the Korean National Healthcare-associated Infections Surveillance System (KONIS): an intensive care unit module report

BACKGROUND

National surveillance data should be validated to identify methodological problems within the surveillance programme and data quality issues.

AIM

To test the validity of healthcare-associated infection (HAI) rate data from the Korean National Healthcare-associated Infections Surveillance System (KONIS).

METHODS

Records from intensive care units of 12 (14.8%) of 81 participating hospitals for January-March 2014 were examined. The validation team reviewed 406 medical records of 110 patients with 114 reported HAIs - including 34 urinary tract infections (UTIs), 57 bloodstream infections (BSIs) and 23 cases of pneumonia (PNEU) - and 296 patients with no reported HAIs during one-day visits conducted in August and September 2014. The reviewers' diagnosis of HAI was regarded as the reference standard; in ambiguous cases, the KONIS Steering Committee confirmed the diagnosis of HAI.

FINDINGS

Sensitivity values for UTIs, BSIs and PNEU were 85.3%, 74.0% and 66.7%, and specificity values were 98.7%, 99.1% and 98.7%, respectively. Positive predictive values were 85.3%, 94.7% and 78.3%, and negative predictive values were 98.7%, 94.6% and 97.7%, respectively. Sensitivity for PNEU was lower than that for UTIs and BSIs. The hospitals participating in KONIS infrequently reported conditions that were not HAIs. Sensitivity for BSIs was lower in this study than in KONIS validation studies conducted in 2008 and 2010.

CONCLUSIONS

KONIS data are generally reliable; however, sensitivity for BSIs exhibited a decrease. This study shows the need for ongoing validation and continuous training of surveillance personnel to maintain the accuracy of surveillance data.

Interrater Reliability of Surveillance for Ventilator-Associated Events and Pneumonia

OBJECTIVE

To compare interrater reliabilities for ventilator-associated event (VAE) surveillance, traditional ventilator-associated pneumonia (VAP) surveillance, and clinical diagnosis of VAP by intensivists.

DESIGN

A retrospective study nested within a prospective multicenter quality improvement study.

SETTING

Intensive care units (ICUs) within 5 hospitals of the Centers for Disease Control and Prevention Epicenters.

PATIENTS

Patients who underwent mechanical ventilation.

METHODS

We selected 150 charts for review, including all VAEs and traditionally defined VAPs identified during the primary study and randomly selected charts of patients without VAEs or VAPs. Each chart was independently reviewed by 2 research assistants (RAs) for VAEs, 2 hospital infection preventionists (IPs) for traditionally defined VAP, and 2 intensivists for any episodes of pulmonary deterioration. We calculated interrater agreement using κ estimates.

RESULTS

The 150 selected episodes spanned 2,500 ventilator days. In total, 93–96 VAEs were identified by RAs; 31–49 VAPs were identified by IPs, and 29–35 VAPs were diagnosed by intensivists. Interrater reliability between RAs for VAEs was high (κ, 0.71; 95% CI, 0.59–0.81). Agreement between IPs using traditional VAP criteria was slight (κ, 0.12; 95% CI, −0.05–0.29). Agreement between intensivists was slight regarding episodes of pulmonary deterioration (κ 0.22; 95% CI, 0.05–0.39) and was fair regarding whether episodes of deterioration were attributable to clinically defined VAP (κ, 0.34; 95% CI, 0.17–0.51). The clinical correlation between VAE surveillance and intensivists’ clinical assessments was poor.

CONCLUSIONS

Prospective surveillance using VAE criteria is more reliable than traditional VAP surveillance and clinical VAP diagnosis; the correlation between VAEs and clinically recognized pulmonary deterioration is poor.

Infect Control Hosp Epidemiol 2017;38:172–178

Standardized Infection Surveillance in Long-Term Care Interfacility Comparisons From a Regional Cohort of Facilities

Objectives:

To measure infection rates in a regional cohort of long-term-care facilities (LTCFs) using standard surveillance methods and to analyze different methods for interfacility comparisons.

Setting:

Seventeen LTCFs in Idaho.

Design:

Prospective, active surveillance for LTCF-acquired infections using standard definitions and case-finding methods was conducted from July 2001 to June 2002. All surveillance data were combined and individual facility performance was compared with the aggregate employing a variety of statistical and graphic methods.

Results:

The surveillance data set consisted of 472,019 resident-days of care with 1,717 total infections for a pooled mean rate of 3.64 infections per 1,000 resident-days. Specific infections included respiratory (828; rate, 1.75), skin and soft tissue (520; rate, 1.10), urinary tract (282; rate, 0.60), gastrointestinal (77; rate, 0.16), unexplained febrile illnesses (6; rate, 0.01), and bloodstream (4; rate, 0.01). Initially, methods adopted from the National Nosocomial Infections Surveillance System were used comparing individual rates with pooled means and percentiles of distribution. A more sensitive method appeared to be detecting statistically significant deviations (based on chi-square analysis) of the individual facility rates from the aggregate of all other facilities. One promising method employed statistical process control charts (U charts) adjusted to compare individual rates with aggregate monthly rates, providing simultaneous visual and statistical comparisons. Small multiples graphs were useful in providing images valid for rapid concurrent comparison of all facilities.

Conclusion:

Interfacility comparisons have been demonstrated to be valuable for hospital infection control programs, but have not been studied extensively in LTCFs.

Administrative Data Fail to Accurately Identify Cases of Healthcare-Associated Infection

Objective.

Some policy makers have embraced public reporting of healthcare-associated infections (HAIs) as a strategy for improving patient safety and reducing healthcare costs. We compared the accuracy of 2 methods of identifying cases of HAI: review of administrative data and targeted active surveillance.

Design, Setting, and Participants.

A cross-sectional prospective study was performed during a 9-month period in 2004 at the Children's Hospital of Philadelphia, a 418-bed academic pediatric hospital. “True HAI” cases were defined as those that met the definitions of the National Nosocomial Infections Surveillance System and that were detected by a trained infection control professional on review of the medical record. We examined the sensitivity and the positive and negative predictive values of identifying HAI cases by review of administrative data and by targeted active surveillance.

Results.

We found similar sensitivities for identification of HAI cases by review of administrative data (61%) and by targeted active surveillance (76%). However, the positive predictive value of identifying HAI cases by review of administrative data was poor (20%), whereas that of targeted active surveillance was 100%.

Conclusions.

The positive predictive value of identifying HAI cases by targeted active surveillance is very high. Additional investigation is needed to define the optimal detection method for institutions that provide HAI data for comparative analysis.

Guidance on Public Reporting of Healthcare-Associated Infections: Recommendations of the Healthcare Infection Control Practices Advisory Committee

Consumer demand for healthcare information, including data about the performance of healthcare providers, has increased steadily during the past decade. Many state and national initiatives are under way to mandate or induce healthcare organizations to publicly disclose information regarding institutional and physician performance. Mandatory public reporting of healthcare performance is intended to enable stakeholders, including consumers, to make more informed choices on healthcare issues.

Public reporting of healthcare performance information has taken several forms. Healthcare performance reports (report cards and honor rolls) typically describe the outcomes of medical care in terms of mortality, selected complications, or medical errors and, to a lesser extent, economic outcomes. Increasingly, process measures (ie, measurement of adherence to recommended healthcare practices, such as hand hygiene) are being used as an indicator of how well an organization adheres to established standards of practice with the implicit assumption that good processes lead to good healthcare outcomes. National healthcare quality improvement initiatives, notably those of the Joint Commission on the Accreditation of Healthcare Organizations (JCAHO), the Centers for Medicare & Medicaid Services (CMS), and the Hospital Quality Alliance, use process measures in their public reporting initiatives.

Data requirements for electronic surveillance of healthcare-associated infections

Electronic surveillance for healthcare-associated infections (HAIs) is increasingly widespread. This is driven by multiple factors: a greater burden on hospitals to provide surveillance data to state and national agencies, financial pressures to be more efficient with HAI surveillance, the desire for more objective comparisons between healthcare facilities, and the increasing amount of patient data available electronically. Optimal implementation of electronic surveillance requires that specific information be available to the surveillance systems. This white paper reviews different approaches to electronic surveillance, discusses the specific data elements required for performing surveillance, and considers important issues of data validation.

A Web-Based, Hospital-Wide Health Care-Associated Bloodstream Infection Surveillance and Classification System: Development and Evaluation

Background

Surveillance of health care-associated infections is an essential component of infection prevention programs, but conventional systems are labor intensive and performance dependent.

Objective

To develop an automatic surveillance and classification system for health care-associated bloodstream infection (HABSI), and to evaluate its performance by comparing it with a conventional infection control personnel (ICP)-based surveillance system.

Methods

We developed a Web-based system that was integrated into the medical information system of a 2200-bed teaching hospital in Taiwan. The system automatically detects and classifies HABSIs.

Results

In this study, the number of computer-detected HABSIs correlated closely with the number of HABSIs detected by ICP by department (n=20; r=.999 P<.001) and by time (n=14; r=.941; P<.001). Compared with reference standards, this system performed excellently with regard to sensitivity (98.16%), specificity (99.96%), positive predictive value (95.81%), and negative predictive value (99.98%). The system enabled decreasing the delay in confirmation of HABSI cases, on average, by 29 days.

Conclusions

This system provides reliable and objective HABSI data for quality indicators, improving the delay caused by a conventional surveillance system.

An electronic surveillance tool for catheter-associated urinary tract infection in intensive care units

BACKGROUND

Traditional methods of surveillance of catheter-associated urinary tract infections (CAUTIs) are error-prone and resource-intensive. To resolve these issues, we developed a highly sensitive electronic surveillance tool.

OBJECTIVE

To develop an electronic surveillance tool for CAUTIs and assess its performance.

METHODS

The study was conducted at a 947-bed tertiary care center. Patients included adults aged ≥18 years admitted to an intensive care unit between January 10 and June 30, 2012, with an indwelling urinary catheter during their admission. We identified CAUTIs using 4 methods: traditional surveillance (TS) (ie, manual chart review by ICPs), an electronic surveillance (ES) tool, augmented electronic surveillance (AES) (ie, ES with chart review on a subset of cases), and reference standard (RS) (ie, a subset of CAUTIs originally ascertained by TS or ES, confirmed by review). We assessed performance characteristics to RS for reviewed cases.

RESULTS

We identified 417 candidate CAUTIs in 308 patients; 175 (42.0%) of these candidate CAUTIs were selected for review, yielding 32 confirmed CAUTIs in 22 patients (RS). Compared with RS, the sensitivities of TS, ES, and AES were 43.8% (95% confidence interval [CI], 26.4%-62.3%), 100.0% (95% CI, 89.1%-100.0%), and 100.0% (95% CI, 89.1%-100.0%). Specificities were 82.5% (95% CI, 75.3%-88.4%), 2.8% (95% CI, 0.8%-7.0%), and 100.0% (95% CI, 97.5%-100.0%).

CONCLUSIONS

Electronic CAUTI surveillance offers a streamlined approach to improve reliability and resource burden of surveillance.

Central line-associated blood stream infections in pediatric intensive care units: Longitudinal trends and compliance with bundle strategies

BACKGROUND

Knowing the temporal trend central line-associated bloodstream infection (CLABSI) rates among U.S. pediatric intensive care units (PICUs), the current extent of central line bundle compliance, and the impact of compliance on rates is necessary to understand what has been accomplished and can be improved in CLABSI prevention.

METHODS

This is a longitudinal study of PICUs in National Healthcare Safety Network hospitals and a cross-sectional survey of directors and managers of infection prevention and control departments regarding PICU CLABSI prevention practices, including self-reported compliance with elements of central line bundles. Associations between 2011-2012 PICU CLABSI rates and infection prevention practices were examined.

RESULTS

Reported CLABSI rates decreased during the study period, from 5.8 per 1,000 line days in 2006 to 1.4 in 2011-2012 (P < .001). Although 73% of PICUs had policies for all central line prevention practices, only 35% of those with policies reported ≥95% compliance. PICUs with ≥95% compliance with central line infection prevention policies had lower reported CLABSI rates, but this association was statistically insignificant.

CONCLUSION

There was a nonsignificant trend in decreasing CLABSI rates as PICUs improved bundle policy compliance. Given that few PICUs reported full compliance with these policies, PICUs increasing their efforts to comply with these policies may help reduce CLABSI rates.

Accuracy of using automated methods for detecting adverse events from electronic health record data: a research protocol

Background

Adverse events are associated with significant morbidity, mortality and cost in hospitalized patients. Measuring adverse events is necessary for quality improvement, but current detection methods are inaccurate, untimely and expensive. The advent of electronic health records and the development of automated methods for encoding and classifying electronic narrative data, such as natural language processing, offer an opportunity to identify potentially better methods. The objective of this study is to determine the accuracy of using automated methods for detecting three highly prevalent adverse events: a) hospital-acquired pneumonia, b) catheter-associated bloodstream infections, and c) in-hospital falls.

Methods/design

This validation study will be conducted at two large Canadian academic health centres: the McGill University Health Centre (MUHC) and The Ottawa Hospital (TOH). The study population consists of all medical, surgical and intensive care unit patients admitted to these centres between 2008 and 2014. An automated detection algorithm will be developed and validated for each of the three adverse events using electronic data extracted from multiple clinical databases. A random sample of MUHC patients will be used to develop the automated detection algorithms (cohort 1, development set). The accuracy of these algorithms will be assessed using chart review as the reference standard. Then, receiver operating characteristic curves will be used to identify optimal cut points for each of the data sources. Multivariate logistic regression and the areas under curve (AUC) will be used to identify the optimal combination of data sources that maximize the accuracy of adverse event detection. The most accurate algorithms will then be validated on a second random sample of MUHC patients (cohort 1, validation set), and accuracy will be measured using chart review as the reference standard. The most accurate algorithms validated at the MUHC will then be applied to TOH data (cohort 2), and their accuracy will be assessed using a reference standard assessment of the medical chart.

Discussion

There is a need for more accurate, timely and efficient measures of adverse events in acute care hospitals. This is a critical requirement for evaluating the effectiveness of preventive interventions and for tracking progress in patient safety through time.

Validation of Surgical Site Infection Surveillance in The Netherlands

Objectives.

To describe how continuous validation of data on surgical site infection (SSI) is being performed in the Dutch National Nosocomial Infection Surveillance System (Preventie Ziekenhuisinfecties door Surveillance [PREZIES]), to assess the quality and accuracy of the PREZIES data, and to present the corresponding outcomes of the assessment.

Design.

Mandatory, 1-day on-site validation visit to participating hospitals every 3 years. The process of surveillance, including the quality of the method of data collection, is validated by means of a structured interview. The use of SSI criteria is validated by review of medical records, with the judgment of the validation team as the criterion standard.

Setting.

Hospitals participating in PREZIES.

Results.

During 1999-2004, the validation team visited 40 hospitals and reviewed 859 medical charts. There was no deviation between reports of SSI by infection control professionals and findings by the PREZIES validation team at 30 hospitals and 1 deviation in each of 10 hospitals; the positive predictive value was 0.97, and the negative predictive value was 0.99. The validation team often gave advice to the hospital, aimed at perfecting the process of surveillance. On 2 occasions, data were removed from the PREZIES database after the validation visit revealed deviations from the SSI surveillance protocol that could have resulted in nonrepresentative SSI rate data.

Conclusions.

PREZIES is confident that the assembled Dutch SSI surveillance data are reliable and robust and are sufficiently accurate to be used as a reference for interhospital comparison. PREZIES will continue performing on-site validation visits, to improve the process of surveillance and ensure the reliability of the surveillance data.

Introduction: Improving Patient Safety Through Infection Control: A New Healthcare Imperative

Many healthcare organizations, professional associations, government and accrediting agencies, legislators, regulators, payers, and consumer advocacy groups have advanced the prevention of healthcare-associated infections as a national imperative, stimulating the creation of “A Compendium of Strategies to Prevent Healthcare-Associated Infections in Acute Care Hospitals” in this supplement. In this introduction, we provide background and context and discuss the major issues that shaped the recommendations included in the compendium.

Statewide Validation of Hospital-Reported Central Line–Associated Bloodstream Infections: Oregon, 2009

Background.

Mandatory reporting of healthcare-associated infections is common, but underreporting by hospitals limits meaningful interpretation.

Objective.

To validate mandatory intensive care unit (ICU) central line–associated bloodstream infection (CLABSI) reporting by Oregon hospitals.

Design.

Blinded comparison of ICU CLABSI determination by hospitals and health department–based external reviewers with group adjudication.

Setting.

Forty-four Oregon hospitals required by state law to report ICU CLABSIs.

Participants.

Seventy-six patients with ICU CLABSIs and a systematic sample of 741 other patients with ICU-related bacteremia episodes.

Methods.

External reviewers examined medical records and determined CLABSI status. All cases with CLABSI determinations discordant from hospital reporting were adjudicated through formal discussion with hospital staff, a process novel to validation of CLABSI reporting.

Results.

Hospital representatives and external reviewers agreed on CLABSI status in 782 (96%) of 817 bacteremia episodes (k = 0.77 [95% confidence interval (CI), 0.70-0.84]). Among the 27 episodes identified as CLABSIs by external reviewers but not reported by hospitals, the final status was CLABSI in 16 (59%). The measured sensitivities of hospital ICU CLABSI reporting were 72% (95% CI, 62%-81%) with adjudicated CLABSI determination as the reference standard and 60% (95% CI, 51%-69%) with external review alone as the reference standard (P = .07). Validation increased the statewide ICU CLABSI rate from 1.21 (95% CI, 0.95-1.51) to 1.54 (95% CI, 1.25-1.88) CLABSIs/1,000 central line–days; ICU CLABSI rates increased by more than 1.00 CLABSI/1,000 central line–days in 6 (14%) hospitals.

Conclusions.

Validating hospital CLABSI reporting improves accuracy of hospital-based CLABSI surveillance. Discussing discordant findings improves the quality of validation.

Detection of Postoperative Surgical-Site Infections: Comparison of Health Plan–Based Surveillance With Hospital-Based Programs

Background:

Review of health plan administrative data has been shown to be more sensitive than other methods for identifying postdischarge surgical-site infections (SSIs), but there has not been a direct comparison between this method and hospital-based surveillance for all infections, including those diagnosed before discharge. We compared these two methods for identifying SSIs following coronary artery bypass graft (CABG) procedures:.

Methods:

We studied 1,352 CABG procedures performed among members of one health plan from March 1993 through June 1997. Health plan administrative records were reviewed based on claims containing diagnoses or procedures suggestive of infection or outpatient dispensing of antibiotics appropriate for SSI. Hospital-based surveillance information was also reviewed. SSI rates were calculated based on the total events identified by either mechanism.

Results:

Postdischarge information was reviewed for 328 (85%) of 388 procedures. SSIs were confirmed in 167 patients (13% overall risk of confirmed SSI; range, 3% to 14% in the 5 hospitals). The overall sensitivity of hospital-based surveillance was 49.7% (83 of 167), and that of health plan data was 71.8% (120 of 167). There was no significant difference among hospitals in the sensitivity of either surveillance mechanism.

Conclusions:

Surveillance based on health plan data identified more postoperative infections, including those occurring before discharge, than did hospital-based surveillance. Screening administrative data and pharmacy activity may be an important adjunct to SSI surveillance, allowing efficient comparison of hospital-specific rates. Interpretation of differences among hospitals' infection rates requires case mix adjustment and understanding of variations in hospitals' discharge diagnosis coding practices

Single-center study of interrater agreement in the identification of central line-associated bloodstream infection

BACKGROUND

Interrater reliability of central line-associated bloodstream infection (CLABSI) determination has not been well studied. The present study evaluated interrater reliability between infection preventionists (IPs) for CLABSI- and other bloodstream infection (BSI)-related factors and examined whether any nurse characteristics are associated with interrater reliability.

METHODS

A total of 165 blood cultures were reviewed by 2 IPs assigned at random. Reliability outcomes were CLABSI, infection type (hospital- or community-acquired), presence of a central line, primary versus secondary BSI, secondary source of BSI, and IP-determined source of BSI (primary, secondary, or indeterminate). Kappa coefficients were calculated. Logistic regression was used to evaluate associations between IP characteristics and agreement on diagnosis of CLABSI.

RESULTS

CLABSI agreement was moderate in IP pairs (κ = 0.562 ± 0.080) and not associated with IP characteristics. After controlling for IP characteristics associated with secondary outcomes, agreement regarding secondary source was more likely in pairs with a larger absolute difference in years employed (P = .013), and agreement regarding infection source was more likely in pairs with larger differences in years employed and duration of certification (P = .025).

CONCLUSIONS

The rate of IP agreement regarding CLABSI was moderate and not associated with IP characteristics, reflecting adequate training. Education and reassessment of definitions may promote higher rates of agreement between IPs.

Validity analysis of a unique infection surveillance system in the intensive care unit by analysis of a data warehouse built through a workflow-integrated software application

BACKGROUND

An electronic decision support programme was developed within the intensive care unit (ICU) that provides an overview of all infection-related patient data, and allows ICU physicians to add clinical information during patient rounds, resulting in prospective compilation of a database.

AIM

To assess the validity of computer-assisted surveillance (CAS) of ICU-acquired infection performed by analysis of this database.

METHODS

CAS was compared with prospective paper-based surveillance (PBS) for ICU-acquired respiratory tract infection (RTI), bloodstream infection (BSI) and urinary tract infection (UTI) over four months at a 36-bed medical and surgical ICU. An independent panel reviewed the data in the case of discrepancy between CAS and PBS.

FINDINGS

PBS identified 89 ICU-acquired infections (13 BSI, 18 UTI, 58 RTI) and CAS identified 90 ICU-acquired infections (14 BSI, 17 UTI, 59 RTI) in 876 ICU admissions. There was agreement between CAS and PBS on 13 BSI (100 %), 14 UTI (77.8 %) and 42 RTI (72.4 %). Overall, there was agreement on 69 infections (77.5%), resulting in a kappa score of 0.74. Discrepancy between PBS and CAS was the result of capture error in 11 and 14 infections, respectively. Interobserver disagreement on probability (13 RTI) and focus (two RTI, one UTI) occurred for 16 episodes. The time required to collect information using CAS is less than 30% of the time required when using PBS.

CONCLUSION

CAS for ICU-acquired infection by analysis of a database built through daily workflow is a feasible surveillance method and has good agreement with PBS. Discrepancy between CAS and PBS is largely due to interobserver variability.

Data use and effectiveness in electronic surveillance of healthcare associated infections in the 21st century: a systematic review

OBJECTIVE

As more electronic health records have become available during the last decade, we aimed to uncover recent trends in use of electronically available patient data by electronic surveillance systems for healthcare associated infections (HAIs) and identify consequences for system effectiveness.

METHODS

A systematic review of published literature evaluating electronic HAI surveillance systems was performed. The PubMed service was used to retrieve publications between January 2001 and December 2011. Studies were included in the review if they accurately described what electronic data were used and if system effectiveness was evaluated using sensitivity, specificity, positive predictive value, or negative predictive value. Trends were identified by analyzing changes in the number and types of electronic data sources used.

RESULTS

26 publications comprising discussions on 27 electronic systems met the eligibility criteria. Trend analysis showed that systems use an increasing number of data sources which are either medico-administrative or clinical and laboratory-based data. Trends on the use of individual types of electronic data confirmed the paramount role of microbiology data in HAI detection, but also showed increased use of biochemistry and pharmacy data, and the limited adoption of clinical data and physician narratives. System effectiveness assessments indicate that the use of heterogeneous data sources results in higher system sensitivity at the expense of specificity.

CONCLUSIONS

Driven by the increased availability of electronic patient data, electronic HAI surveillance systems use more data, making systems more sensitive yet less specific, but also allow systems to be tailored to the needs of healthcare institutes' surveillance programs.

Interobserver agreement of Centers for Disease Control and Prevention criteria for classifying infections in critically ill patients

OBJECTIVES

Correct classification of the source of infection is important in observational and interventional studies of sepsis. Centers for Disease Control and Prevention criteria are most commonly used for this purpose, but the robustness of these definitions in critically ill patients is not known. We hypothesized that in a mixed ICU population, the performance of these criteria would be generally reduced and would vary among diagnostic subgroups.

DESIGN

Prospective cohort.

SETTING

Data were collected as part of a cohort of 1,214 critically ill patients admitted to two hospitals in The Netherlands between January 2011 and June 2011.

PATIENTS

Eight observers assessed a random sample of 168 of 554 patients who had experienced at least one infectious episode in the ICU. Each patient was assessed by two randomly selected observers who independently scored the source of infection (by affected organ system or site), the plausibility of infection (rated as none, possible, probable, or definite), and the most likely causative pathogen. Assessments were based on a post hoc review of all available clinical, radiological, and microbiological evidence. The observed diagnostic agreement for source of infection was classified as partial (i.e., matching on organ system or site) or complete (i.e., matching on specific diagnostic terms), for plausibility as partial (2-point scale) or complete (4-point scale), and for causative pathogens as an approximate or exact pathogen match. Interobserver agreement was expressed as a concordant percentage and as a kappa statistic.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 206 infectious episodes were observed. Agreement regarding the source of infection was 89% (183/206) and 69% (142/206) for a partial and complete diagnostic match, respectively. This resulted in a kappa of 0.85 (95% CI, 0.79-0.90). Agreement varied from 63% to 91% within major diagnostic categories and from 35% to 97% within specific diagnostic subgroups, with the lowest concordance observed in cases of ventilator-associated pneumonia. In the 142 episodes for which a complete match on source of infection was obtained, the interobserver agreement for plausibility of infection was 83% and 65% on a 2- and 4-point scale, respectively. For causative pathogen, agreement was 78% and 70% for an approximate and exact pathogen match, respectively.

CONCLUSIONS

Interobserver agreement for classifying sources of infection using Centers for Disease Control and Prevention criteria was excellent overall. However, full concordance on all aspects of the diagnosis between independent observers was rare for some types of infection, in particular for ventilator-associated pneumonia.

Risk factors for methicillin-resistant Staphylococcus aureus bacteraemia differ depending on the control group chosen

Methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia cause significant morbidity and mortality in hospitalized patients. Using a nested case-control design, 204 MRSA bacteraemia cases were compared to 301 unmatched methicillin-susceptible Staphylococcus aureus (MSSA) bacteraemia controls and were matched 1:2 with non-infected controls. The independent risk factors for MRSA bacteraemia compared to MSSA bacteraemia were older age (P = 0·048), major organ transplant during current hospital stay (P = 0·016) and quinolone use (P = 0·016). Cases were more likely than non-infected controls to have renal failure (P = 0·003), cirrhosis (P = 0·013), and a central venous catheter (P = 0·003) after controlling for other risk factors. This large case-control study made it possible to assess risk factors for MRSA bacteraemia using two sets of controls and showed that risk factors differed greatly depending on the control group chosen. These results confirm the need for careful selection of appropriate control groups and the need to carefully adjust for underlying severity of illness.

Variations in identification of healthcare-associated infections

OBJECTIVE

Little is known about whether those performing healthcare-associated infection (HAI) surveillance vary in their interpretations of HAI definitions developed by the Centers for Disease Control and Prevention's National Healthcare Safety Network (NHSN). Our primary objective was to characterize variations in these interpretations using clinical vignettes. We also describe predictors of variation in responses.

DESIGN

Cross-sectional study.

SETTING

United States.

PARTICIPANTS

A sample of US-based members of the Society for Healthcare Epidemiology of America (SHEA) Research Network.

METHODS

Respondents assessed whether each of 6 clinical vignettes met criteria for an NHSN-defined HAI. Individual- and institutional-level data were also gathered.

RESULTS

Surveys were distributed to 143 SHEA Research Network members from 126 hospitals. In total, 113 responses were obtained, representing at least 61 unique hospitals (30 respondents did not identify a hospital); 79.2% (84 of 106 nonmissing responses) were infection preventionists, and 79.4% (81 of 102 nonmissing responses) worked at academic hospitals. Among the 6 vignettes, the proportion of respondents correctly characterizing the vignettes was as low as 27.3%. Combining all 6 vignettes, the mean percentage of correct responses was 61.1% (95% confidence interval, 57.7%-63.8%). Percentage of correct responses was associated with presence of a clinical background (ie, nursing or physician degrees) but not with hospital size or infection prevention and control department characteristics.

CONCLUSIONS

Substantial heterogeneity exists in the application of HAI definitions in this survey of infection preventionists and hospital epidemiologists. Our data suggest a need to better clarify these definitions, especially when comparing HAI rates across institutions.

Evaluating application of the National Healthcare Safety Network central line-associated bloodstream infection surveillance definition: a survey of pediatric intensive care and hematology/oncology units

OBJECTIVE

To evaluate the application of the National Healthcare Safety Network (NHSN) central line-associated bloodstream infection (CLABSI) definition in pediatric intensive care units (PICUs) and pediatric hematology/oncology units (PHOUs) participating in a multicenter quality improvement collaborative to reduce CLABSIs; to identify sources of variability in the application of the definition.

DESIGN

Online survey using 18 standardized case scenarios. Each described a positive blood culture in a patient and required a yes- or-no answer to the question "Is this a CLABSI?" NHSN staff responses were the reference standard.

SETTING

Sixty-five US PICUs and PHOUs.

PARTICIPANTS

Staff who routinely adjudicate CLABSIs using NHSN definitions.

RESULTS

Sixty responses were received from 58 (89%) of 65 institutions; 78% of respondents were infection preventionists, infection control officers, or infectious disease physicians. Responses matched those of NHSN staff for 78% of questions. The mean (SE) percentage of concurring answers did not differ for scenarios evaluating application of 1 of the 3 criteria ("known pathogen," 78% [1.7%]; "skin contaminant, >1 year of age," 76% [SE, 2.5%]; "skin contaminant, ≤1 year of age," 81% [3.8%]; [Formula: see text]). The mean percentage of concurring answers was lower for scenarios requiring respondents to determine whether a CLABSI was present or incubating on admission (64% [4.6%]; [Formula: see text]) or to distinguish between primary and secondary bacteremia (65% [2.5%]; [Formula: see text]).

CONCLUSIONS

The accuracy of application of the CLABSI definition was suboptimal. Efforts to reduce variability in identifying CLABSIs that are present or incubating on admission and in distinguishing primary from secondary bloodstream infection are needed.

Quality control of the surveillance programme of ICU-acquired infection (ENVIN-HELICS registry) in Spain

BACKGROUND

Data validation is an essential aspect for the accuracy of a nosocomial infection surveillance registry.

AIM

To report the results of the first quality control programme in the national surveillance programme of intensive care unit (ICU)-acquired infection in Spain (ENVIN-HELICS registry).

METHOD

During 2008, of 13,824 records included in the database, 1500 (10.8%) registries from 20 ICUs were reviewed. These ICUs were selected at random and stratified according to the number of cases included in the registry. The proportion of infected patients, which was 9.6% [95% confidence interval (CI) 8.09-11.16], was maintained during the selection of cases for review. Two physicians were trained for the purpose of the study and undertook the review.

RESULTS

Overall sensitivity, specificity and positive and negative predictive values of the ENVIN-HELICS registry for the identification of patients with any device-related infection acquired during their ICU stay were 86.0% (95% CI 80.0-92.0), 98.7% (95% CI 82.19-93.6), 87.9% (95% CI 82.19-93.6) and 98.5% (95% CI 97.8-99.2), respectively, with a kappa index of 0.85 (95% CI 0.79-0.92). Secondary bloodstream infection had the lowest sensitivity (59.3%), and intubation-associated pneumonia had the highest sensitivity (86.3%).

CONCLUSION

There was good correlation between data reported by the registrars and data validated by auditors, confirming the reliability of the ENVIN-HELICS registry.

Central line-associated infections as defined by the Centers for Medicare and Medicaid Services' Hospital-acquired condition versus standard infection control surveillance: why hospital compare seems conflicted

OBJECTIVE

To evaluate the concordance of case-finding methods for central line-associated infection as defined by Centers for Medicare and Medicaid Services (CMS) hospital-acquired condition (HAC) compared with traditional infection control (IC) methods.

SETTING

One tertiary care and 2 community hospitals in North Carolina.

PATIENTS

Adult and pediatric hospitalized patients determined to have central line infection by either case-finding method.

METHODS

We performed a retrospective comparative analysis of infection detected using HAC versus standard IC central line-associated bloodstream infection surveillance from October 1, 2007, through December 31, 2009. One billing and 2 IC databases were queried and matched to determine the number and concordance of cases identified by each method. Manual review of 25 cases from each discordant category was performed. Sensitivity and positive predictive value (PPV) were calculated using IC as criterion standard.

RESULTS

A total of 1,505 cases were identified: 844 by International Classification of Diseases, Ninth Revision (ICD-9), and 798 by IC. A total of 204 cases (24%) identified by ICD-9 were deemed not present at hospital admission by coders. Only 112 cases (13%) were concordant. HAC sensitivity was 14% and PPV was 55% compared with IC. Concordance was low regardless of hospital type. Primary reasons for discordance included differences in surveillance and clinical definitions, clinical uncertainty, and poor documentation.

CONCLUSIONS

The case-finding method used by CMS HAC and the methods used for traditional IC surveillance frequently do not agree. This can lead to conflicting results when these 2 measures are used as hospital quality metrics.

Discord among performance measures for central line-associated bloodstream infection

BACKGROUND

Central line-associated bloodstream infection (CLABSI) is a national target for mandatory reporting and a Centers for Medicare and Medicaid Services target for value-based purchasing. Differences in chart review versus claims-based metrics used by national agencies and groups raise concerns about the validity of these measures.

OBJECTIVE

Evaluate consistency and reasons for discordance among chart review and claims-based CLABSI events.

METHODS

We conducted 2 multicenter retrospective cohort studies within 6 academic institutions. A total of 150 consecutive patients were identified with CLABSI on the basis of National Healthcare Safety Network (NHSN) criteria (NHSN cohort), and an additional 150 consecutive patients were identified with CLABSI on the basis of claims codes (claims cohort). All events had full-text medical record reviews and were identified as concordant or discordant with the other metric.

RESULTS

In the NHSN cohort, there were 152 CLABSIs among 150 patients, and 73.0% of these cases were discordant with claims data. Common reasons for the lack of associated claims codes included coding omission and lack of physician documentation of bacteremia cause. In the claims cohort, there were 150 CLABSIs among 150 patients, and 65.3% of these cases were discordant with NHSN criteria. Common reasons for the lack of NHSN reporting were identification of non-CLABSI with bacteremia meeting Centers for Disease Control and Prevention (CDC) criteria for an alternative infection source.

CONCLUSION

Substantial discordance between NHSN and claims-based CLABSI indicators persists. Compared with standardized CDC chart review criteria, claims data often had both coding omissions and misclassification of non-CLABSI infections as CLABSI. Additionally, claims did not identify any additional CLABSIs for CDC reporting. NHSN criteria are a more consistent interhospital standard for CLABSI reporting.

Effectiveness of an automated surveillance system for intensive care unit-acquired infections

This study assessed the effectiveness of a fully automated surveillance system for the detection of healthcare-associated infections (HCAIs) in intensive care units. Manual ward surveillance (MS) and electronic surveillance (ES) were performed for two intensive care units of the Vienna General Hospital. All patients admitted for a period longer than 48 h between 13 November 2006 and 7 February 2007 were evaluated according to HELICS-defined rules for HCAI. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and personnel time spent per surveillance type were calculated. Ninety-three patient admissions were observed, whereby 30 HCAI episodes were taken as a reference standard. Results with MS versus ES were: sensitivity 40% versus 87%, specificity 94% versus 99%, PPV 71% versus 96%, NPV 80% versus 95%, and time spent per surveillance type 82.5 h versus 12.5 h. In conclusion, ES was found to be more effective than MS while consuming fewer personnel resources.

Electronic measures of surgical site infection: implications for estimating risks and costs

OBJECTIVE

Electronic measures of surgical site infections (SSIs) are being used more frequently in place of labor-intensive measures. This study compares performance characteristics of 2 electronic measures of SSIs with a clinical measure and studies the implications of using electronic measures to estimate risk factors and costs of SSIs among surgery patients.

METHODS

Data included 1,066 general and vascular surgery patients at a single academic center between 2007 and 2008. Clinical data were from the National Surgical Quality Improvement Program (NSQIP) database, which includes a nurse-derived measure of SSI. We compared the NSQIP SSI measure with 2 electronic measures of SSI: MedMined Nosocomial Infection Marker (NIM) and International Classification of Diseases, Ninth Revision (ICD-9) coding for SSIs. We compared infection rates for each measure, estimated sensitivity and specificity of electronic measures, compared effects of SSI measures on risk factors for mortality using logistic regression, and compared estimated costs of SSIs for measures using linear regression.

RESULTS

SSIs were observed in 8.8% of patients according to the NSQIP definition, 2.6% of patients according to the NIM definition, and 5.8% according to the ICD-9 definition. Logistic regression for each SSI measure revealed large differences in estimated risk factors. NIM and ICD-9 measures overestimated the cost of SSIs by 134% and 33%, respectively.

CONCLUSIONS

Caution should be taken when relying on electronic measures for SSI surveillance and when estimating risk and costs attributable to SSIs. Electronic measures are convenient, but in this data set they did not correlate well with a clinical measure of infection.

Electronic surveillance for healthcare-associated central line-associated bloodstream infections outside the intensive care unit

BACKGROUND

Manual surveillance for central line-associated bloodstream infections (CLABSIs) by infection prevention practitioners is time-consuming and often limited to intensive care units (ICUs). An automated surveillance system using existing databases with patient-level variables and microbiology data was investigated.

METHODS

Patients with a positive blood culture in 4 non-ICU wards at Barnes-Jewish Hospital between July 1, 2005, and December 31, 2006, were evaluated. CLABSI determination for these patients was made via 2 sources; a manual chart review and an automated review from electronically available data. Agreement between these 2 sources was used to develop the best-fit electronic algorithm that used a set of rules to identify a CLABSI. Sensitivity, specificity, predictive values, and Pearson's correlation were calculated for the various rule sets, using manual chart review as the reference standard.

RESULTS

During the study period, 391 positive blood cultures from 331 patients were evaluated. Eighty-five (22%) of these were confirmed to be CLABSI by manual chart review. The best-fit model included presence of a catheter, blood culture positive for known pathogen or blood culture with a common skin contaminant confirmed by a second positive culture and the presence of fever, and no positive cultures with the same organism from another sterile site. The best-performing rule set had an overall sensitivity of 95.2%, specificity of 97.5%, positive predictive value of 90%, and negative predictive value of 99.2% compared with intensive manual surveillance.

CONCLUSIONS

Although CLABSIs were slightly overpredicted by electronic surveillance compared with manual chart review, the method offers the possibility of performing acceptably good surveillance in areas where resources do not allow for traditional manual surveillance.

Use of benchmarking and public reporting for infection control in four high-income countries

Benchmarking of surveillance data for health-care-associated infection (HCAI) has been used for more than three decades to inform prevention strategies and improve patients' safety. In recent years, public reporting of HCAI indicators has been mandated in several countries because of an increasing demand for transparency, although many methodological issues surrounding benchmarking remain unresolved and are highly debated. In this Review, we describe developments in benchmarking and public reporting of HCAI indicators in England, France, Germany, and the USA. Although benchmarking networks in these countries are derived from a common model and use similar methods, approaches to public reporting have been more diverse. The USA and England have predominantly focused on reporting of infection rates, whereas France has put emphasis on process and structure indicators. In Germany, HCAI indicators of individual institutions are treated confidentially and are not disseminated publicly. Although evidence for a direct effect of public reporting of indicators alone on incidence of HCAIs is weak at present, it has been associated with substantial organisational change. An opportunity now exists to learn from the different strategies that have been adopted.

Central line bundle implementation in US intensive care units and impact on bloodstream infections

BACKGROUND

Central line-associated bloodstream infections (CLABSI) represent a serious patient safety issue. To prevent these infections, bundled interventions are increasingly recommended. We examine the extent of adoption of Central Line (CL) Bundle elements throughout US intensive care units (ICU) and determine their effectiveness in preventing CLABSIs.

METHODOLOGY/PRINCIPAL FINDINGS

In this cross-sectional study, National Healthcare Safety Network (NHSN) hospitals provided the following: ICU-specific NHSN-reported rates of CLABSI/1,000 central line days; policies and compliance rates regarding bundle components; and other setting characteristics. In 250 hospitals the mean CLABSI rate was 2.1 per 1000 central line days and 49% reported having a written CL Bundle policy. However, of those that monitored compliance, only 38% reported very high compliance with the CL Bundle. Only when an ICU had a policy, monitored compliance, and had ≥ 95% compliance did CLABSI rates decrease. Complying with any one of three CL Bundle elements resulted in decreased CLABSI rates (β = -1.029, p = 0.015). If an ICU without good bundle compliance achieved high compliance with any one bundle element, we estimated that its CLABSI rate would decrease by 38%.

CONCLUSIONS/SIGNIFICANCE

In NHSN hospitals across the US, the CL Bundle is associated with lower infection rates only when compliance is high. Hospitals must target improving bundle implementation and compliance as opposed to simply instituting policies.

National surveillance of surgical-site infection through register-based analysis of antibiotic use after inguinal hernia repair

BACKGROUND

Systematic surveillance of surgical-site infections is not standard. The aim of this retrospective cohort study was to evaluate the feasibility of using existing national health registers for surveillance of postoperative antibiotic treatment suggestive of surgical-site infection.

METHODS

Data from national registers on hospital admissions and drug use were combined. Antibiotic purchases by 8856 patients subject to ambulatory care for inguinal hernia repair in Sweden during 2006 were ascertained during a 30-day interval immediately after surgery (postsurgical period) and in an 11-month control period (6 months before and 5 months after the postsurgical period).

RESULTS

The incidence of first purchases of skin and soft tissue antibiotics was 245 per 8697 person-months in the first postoperative month and 180 per 52 612 person-months in the preoperative control period, representing a 1-month risk difference of 2.4 (95 per cent confidence interval (c.i.) 2.0 to 2.7) per cent. Hence, a 1-month risk of 2.4 per cent could be attributed tentatively to the surgery. The rate of episodes with antibiotics used mainly for skin and soft tissue infection was sevenfold higher in the first postoperative month than in the control period (rate ratio 7.01, 95 per cent c.i. 5.94 to 8.27).

CONCLUSION

The risk of antibiotic treatment during the postsurgical period was of the same order of magnitude as infection rates reported in the Swedish Hernia Register and review studies. Surveillance of postoperative antibiotic use may be considered as a resource-saving surrogate marker for surgical-site infections or an indicator of inappropriate use.

Developing information technology for infection prevention surveillance

The potential to automate at least part of the surveillance process for health care-associated infections was seen as soon as hospitals began to implement computer systems. Progress toward automated surveillance has been ongoing for the last several decades. But as more information becomes available electronically in the healthcare setting, the promise of electronic surveillance for healthcare-associated infections has become closer to reality. Although true fully automated surveillance is not here yet, significant progress is being made at a number of centers for electronic surveillance of central catheter-associated bloodstream infections, ventilator-associated pneumonia, and other healthcare-associated infections. We review the progress that has been made in this area and issues that need to be addressed as surveillance systems are implemented, as well as promising areas for future development.

Interobserver variability in ventilator-associated pneumonia surveillance

Three infection control personnel and 1 physician independently evaluated 50 ventilated patients for ventilator-associated pneumonia through retrospective chart reviews. The infection control reviewers used Centers for Disease Control and Prevention criteria; the physician used clinical judgment. Infection control personnel labelled between 11 and 20 patients with VAP (kappa = 0.40). The physician diagnosed 7 cases. Interobserver variability in the assessment of ventilator-associated pneumonia is high.

Validation of statewide surveillance system data on central line-associated bloodstream infection in intensive care units in Australia

OBJECTIVE

To measure the interobserver agreement, sensitivity, specificity, positive predictive value, and negative predictive value of data submitted to a statewide surveillance system for identifying central line-associated bloodstream infection (BSI).

DESIGN

Retrospective review of hospital medical records comparing reported data with gold standard according to definitions of central line-associated BSI.

SETTING

Six Victorian public hospitals with more than 100 beds.

METHODS

Reporting of surveillance outcomes was undertaken by infection control practitioners at the hospital sites. Retrospective evaluation of the surveillance process was carried out by independent infection control practitioners from the Victorian Hospital Acquired Infection Surveillance System (VICNISS). A sample of records of patients reported to have a central line-associated BSI were assessed to determine whether they met the definition of central line-associated BSI. A sample of records of patients with bacteremia in the intensive care unit during the assessment period who were not reported as having central line-associated BSI were also assessed to see whether they met the definition of central line-associated BSI.

RESULTS

Records of 108 patients were reviewed; the agreement between surveillance reports and the VICNISS assessment was 67.6% (k = 0.31). Of the 46 reported central line-associated BSIs, 27 were confirmed to be central line-associated BSIs, for a positive predictive value of 59% (95% confidence interval [CI], 43%-73%). Of the 62 cases of bacteremia reviewed that were not reported as central line-associated BSIs, 45 were not associated with a central line, for a negative predictive value of 73% (95% CI, 60%-83%). Estimated sensitivity was 35%, and specificity was 87%. The positive likelihood ratio was 3.0, and the negative likelihood ratio was 0.72.

DISCUSSION

The agreement between the reporting of central line-associated BSI and the gold standard application of definitions was unacceptably low. False-negative results were problematic; more than half of central line-associated BSIs may be missed in Victorian public hospitals.

Impact of revising the National Nosocomial Infection Surveillance System definition for catheter-related bloodstream infection in ICU: reproducibility of the National Healthcare Safety Network case definition in an Australian cohort of infection control professionals

BACKGROUND

Effective and comparable surveillance for central venous catheter-related bloodstream infections (CLABSIs) in the intensive care unit requires a reproducible case definition that can be readily applied by infection control professionals.

METHODS

Using a questionnaire containing clinical cases, reproducibility of the National Nosocomial Infection Surveillance System (NNIS) surveillance definition for CLABSI was assessed in an Australian cohort of infection control professionals participating in the Victorian Hospital Acquired Infection Surveillance System (VICNISS). The same questionnaire was then used to evaluate the reproducibility of the National Healthcare Safety Network (NHSN) surveillance definition for CLABSI. Target hospitals were defined as large metropolitan (1A) or other large hospitals (non-1A), according to the Victorian Department of Human Services. Questionnaire responses of Centers for Disease Control and Prevention NHSN surveillance experts were used as gold standard comparator.

RESULTS

Eighteen of 21 eligible VICNISS centers participated in the survey. Overall concordance with the gold standard was 57.1%, and agreement was highest for 1A hospitals (60.6%). The proportion of congruently classified cases varied according to NNIS criteria: criterion 1 (recognized pathogen), 52.8%; criterion 2a (skin contaminant in 2 or more blood cultures), 83.3%; criterion 2b (skin contaminant in 1 blood culture and appropriate antimicrobial therapy instituted), 58.3%; non-CLABSI cases, 51.4%. When survey questions regarding identification of cases of CLABSI criterion 2b were removed (consistent with the current NHSN definition), overall percentage concordance increased to 62.5% (72.2% for 1A centers).

CONCLUSION

Further educational interventions are required to improve the discrimination of primary and secondary causes of bloodstream infection in Victorian intensive care units. Although reproducibility of the CLABSI case definition is relatively poor, adoption of the revised NHSN definition for CLABSI is likely to improve the concordance of Victorian data with international centers.

Health care-associated infection reporting: the need for ongoing reliability and validity assessment

Government-mandated reporting of health care-associated infections (HAIs) and new reimbursement regulations place a premium on accurate and reliable detection of HAIs. This commentary addresses the challenges and opportunities of having consistent, well-defined, and continuous methods in place to ensure the reliability and validity of HAI detection and reporting. In addition, such procedures could support the development and expertise of infection preventionists. A Web-based clinical vignette model is suggested for improving HAI reporting for hospitals participating in the Centers for Disease Control and Prevention's National Healthcare Safety Network.

Predicting the risk of documented ventilator-associated pneumonia for benchmarking: construction and validation of a score

OBJECTIVES

: To build and validate a ventilator-associated pneumonia risk score for benchmarking. The rate of ventilator-associated pneumonia varies widely with case-mix, a fact that has limited its use for measuring intensive care unit performance.

METHODS

: We studied 1856 patients in the OUTCOMEREA database treated at intensive care unit admission by endotracheal intubation followed by mechanical ventilation for >48 hrs; they were allocated randomly to a training data set (n = 1233) or a validation data set (n = 623). Multivariate logistic regression was used. Calibration of the final model was assessed in both data sets, using the Hosmer-Lemeshow chi-square test and receiver operating characteristic curves.

MEASUREMENTS AND MAIN RESULTS

: Independent risk factors for ventilator-associated pneumonia were male gender (odds ratio = 1.97, 95% confidence interval = 1.32-2.95); SOFA at intensive care unit admission (<3 [reference value], 3-4 [2.57, 1.39-4.77], 5-8 [7.37, 4.24-12.81], >8 [5.81 (3.2-10.52)], no use within 48 hrs after intensive care unit admission of parenteral nutrition (2.29, 1.52-3.45), no broad-spectrum antimicrobials (2.11, 1.46-3.06); and mechanical ventilation duration (<5 days (); 5-7 days (17.55, 4.01-76.85); 7-15 days (53.01, 12.74-220.56); >15 days (225.6, 54.3-936.7). Tests in the training set showed good calibration and good discrimination (area under the curve-receiver operating characteristic curve = 0.881), and both criteria remained good in the validation set (area under the curve-receiver operating characteristic curve = 0.848) and good calibration (Hosmer-Lemeshow chi-square = 9.98, p = .5). Observed ventilator-associated pneumonia rates varied across intensive care units from 9.7 to 26.1 of 1000 mechanical ventilation days but the ratio of observed over theoretical ventilator-associated pneumonia rates was >1 in only two intensive care units.

CONCLUSIONS

: The ventilator-associated pneumonia rate may be useful for benchmarking provided the ratio of observed over theoretical rates is used. External validation of our prediction score is needed.

The effects of laparoscopic cholecystectomy, hysterectomy, and appendectomy on nosocomial infection risks

BACKGROUND

Recent reviews of the literature have concluded that additional, well-defined studies are required to clarify the superiority of laparoscopic or open surgery. This paper presents precise estimates of nosocomial infection risks associated with laparoscopic as compared to open surgery in three procedures: cholecystectomy, appendectomy, and hysterectomy.

METHODS

A retrospective analysis was performed on 11,662 admissions from 22 hospitals that have a nosocomial infection monitoring system. The Nosocomial Infection Marker (NIMtrade mark, patent pending) was used to identify nosocomial infections during hospitalization and post discharge. The dataset was limited to admissions with laparoscopic or open cholecystectomy (32.7%), appendectomy (24.0%), or hysterectomy (43.3%) and was analyzed by source of infection: urinary tract, wounds, respiratory tract, bloodstream, and others. Single- and multivariable logistic regression analyses were performed to control for the following potentially confounding variables: gender, age, type of insurance, complexity of admission on presentation, admission through the emergency department, and hospital case mix index (CMI).

RESULTS

Analyses were based on 399 NIMs in 337 patients. Laparoscopic cholecystectomy and hysterectomy each reduced the overall odds of acquiring nosocomial infections by more than 50% (p < 0.01) Laparoscopic cholecystectomy and hysterectomy also resulted in statistically significantly fewer readmissions with nosocomial infections (p < 0.01). Excluding appendectomy, the odds ratio for laparoscopic versus open NIM-associated readmission was 0.346 (p < 0.01). Laparoscopic appendectomy did not significantly change the odds of acquiring nosocomial infections.

CONCLUSION

As compared to open surgery, laparoscopic cholecystectomy and hysterectomy are associated with statistically significantly lower risks for nosocomial infections. For appendectomy, when comparing open versus laparoscopic approaches, no differences in the rate of nosocomial infections were detected.