Surveillance, reporting, automation, and interventional epidemiology

Strategies to enhance rational use of antibiotics in hospital: a guideline by the German Society for Infectious Diseases

Introduction

In the time of increasing resistance and paucity of new drug development there is a growing need for strategies to enhance rational use of antibiotics in German and Austrian hospitals. An evidence-based guideline on recommendations for implementation of antibiotic stewardship (ABS) programmes was developed by the German Society for Infectious Diseases in association with the following societies, associations and institutions: German Society of Hospital Pharmacists, German Society for Hygiene and Microbiology, Paul Ehrlich Society for Chemotherapy, The Austrian Association of Hospital Pharmacists, Austrian Society for Infectious Diseases and Tropical Medicine, Austrian Society for Antimicrobial Chemotherapy, Robert Koch Institute.

Materials and methods

A structured literature research was performed in the databases EMBASE, BIOSIS, MEDLINE and The Cochrane Library from January 2006 to November 2010 with an update to April 2012 (MEDLINE and The Cochrane Library). The grading of recommendations in relation to their evidence is according to the AWMF Guidance Manual and Rules for Guideline Development.

Conclusion

The guideline provides the grounds for rational use of antibiotics in hospital to counteract antimicrobial resistance and to improve the quality of care of patients with infections by maximising clinical outcomes while minimising toxicity. Requirements for a successful implementation of ABS programmes as well as core and supplemental ABS strategies are outlined. The German version of the guideline was published by the German Association of the Scientific Medical Societies (AWMF) in December 2013.

A gloves-associated outbreak of imipenem-resistant Acinetobacter baumannii in an intensive care unit in Guangdong, China

Background

Imipenem-resistant Acinetobacter baumannii (IRAB) is an important cause of hospital-acquired infection. We aimed to describe an outbreak of IRAB infection and to investigate its possible source in an intensive care unit.

Methods

An environmental investigation was undertaken. Antimicrobial susceptibility testing was performed by microdilution. These isolates were genotyped by use of repetitive extragenic palindromic polymerase chain reaction (rep-PCR; DiversiLab). The study included 11 patients infected with IRAB and 14 control patients free of IRAB. Case and control patients were compared for possible predisposing factors. A multifaceted intervention was implemented to control the outbreak.

Results

Thirty-nine IRABs were isolated from patients and the environmental surveillance culture in August, November, and December 2011. All isolates were resistant to imipenem. The IRAB strains belonged to seven clones (A–G) by the use of rep-PCR. There were four epidemic clones (D–G) in the outbreak, and Clone D was predominant. For the case–control study, patients with chronic obstructive pulmonary disease were susceptible to infection with IRAB. The hospital mortality of the case group was significantly higher than that of the control group.

Conclusions

The outbreak strains were transmitted among infected patients and equipment by inappropriate use of gloves. A combination of aggressive infection control measures is essential for preventing recurrent nosocomial outbreaks of IRAB.

Impact of Electronic Surveillance on Isolation Practices

Objective.

To assess the impact of an electronic surveillance system on isolation practices and rates of methicillin-resistant Staphylococcus aureus (MRSA).

Design.

A pre-post test intervention.

Setting.

Inpatient units (except psychiatry and labor and delivery) in 4 New York City hospitals.

Patients.

All patients for whom isolation precautions were indicated, May 2009–December 2011.

Methods.

Trained observers assessed isolation sign postings, availability of isolation carts, and staff use of personal protective equipment (PPE). Infection rates were obtained from the infection control department. Regression analyses were used to examine the association between the surveillance system, infection prevention practices, and MRSA infection rates.

Results.

A total of 54,159 isolation days and 7,628 staff opportunities for donning PPE were observed over a 31-month period. Odds of having an appropriate sign posted were significantly higher after intervention than before intervention (odds ratio [OR], 1.10 [95% confidence interval {CI}, 1.01–1.20]). Relative to baseline, postintervention sign posting improved significantly for airborne and droplet precautions but not for contact precautions. Sign posting improved for vancomycin-resistant enterococci (OR, 1.51 [95% CI, 1.23–1.86]; P = .0001), Clostridium difficile (OR, 1.59 [95% CI, 1.27–2.02]; P = .00005), and Acinetobacter baumannii (OR, 1.41 [95% CI, 1.21–1.64]; P = .00001) precautions but not for MRSA precautions (OR, 1.11 [95% CI, 0.89–1.39]; P = .36). Staff and visitor adherence to PPE remained low throughout the study but improved from 29.1% to 37.0% after the intervention (OR, 1.14 [95% CI, 1.01–1.29]). MRSA infection rates were not significantly different after the intervention.

Conclusions.

An electronic surveillance system resulted in small but statistically significant improvements in isolation practices but no reductions in infection rates over the short term. Such innovations likely require considerable uptake time.

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.

Biochemical phenotypes to discriminate microbial subpopulations and improve outbreak detection

Background

Clinical microbiology laboratories worldwide constitute an invaluable resource for monitoring emerging threats and the spread of antimicrobial resistance. We studied the growing number of biochemical tests routinely performed on clinical isolates to explore their value as epidemiological markers.

Methodology/Principal Findings

Microbiology laboratory results from January 2009 through December 2011 from a 793-bed hospital stored in WHONET were examined. Variables included patient location, collection date, organism, and 47 biochemical and 17 antimicrobial susceptibility test results reported by Vitek 2. To identify biochemical tests that were particularly valuable (stable with repeat testing, but good variability across the species) or problematic (inconsistent results with repeat testing), three types of variance analyses were performed on isolates of K. pneumonia: descriptive analysis of discordant biochemical results in same-day isolates, an average within-patient variance index, and generalized linear mixed model variance component analysis. Results: 4,200 isolates of K. pneumoniae were identified from 2,485 patients, 32% of whom had multiple isolates. The first two variance analyses highlighted SUCT, TyrA, GlyA, and GGT as “nuisance” biochemicals for which discordant within-patient test results impacted a high proportion of patient results, while dTAG had relatively good within-patient stability with good heterogeneity across the species. Variance component analyses confirmed the relative stability of dTAG, and identified additional biochemicals such as PHOS with a large between patient to within patient variance ratio. A reduced subset of biochemicals improved the robustness of strain definition for carbapenem-resistant K. pneumoniae. Surveillance analyses suggest that the reduced biochemical profile could improve the timeliness and specificity of outbreak detection algorithms.

Conclusions

The statistical approaches explored can improve the robust recognition of microbial subpopulations with routinely available biochemical test results, of value in the timely detection of outbreak clones and evolutionarily important genetic events.

Hospital adoption of automated surveillance technology and the implementation of infection prevention and control programs

BACKGROUND

This research analyzes the relationship between hospital use of automated surveillance technology (AST) for identification and control of hospital-acquired infections (HAI) and implementation of evidence-based infection control practices. Our hypothesis is that hospitals that use AST have made more progress implementing infection control practices than hospitals that rely on manual surveillance.

METHODS

A survey of all acute general care hospitals in California was conducted from October 2008 through January 2009. A structured computer-assisted telephone interview was conducted with the quality director of each hospital. The final sample includes 241 general acute care hospitals (response rate, 83%).

RESULTS

Approximately one third (32.4%) of California's hospitals use AST for monitoring HAI. Adoption of AST is statistically significant and positively associated with the depth of implementation of evidence-based practices for methicillin-resistant Staphylococcus aureus and ventilator-associated pneumonia and adoption of contact precautions and surgical care infection practices. Use of AST is also statistically significantly associated with the breadth of hospital implementation of evidence-based practices across all 5 targeted HAI.

CONCLUSION

Our findings suggest that hospitals using AST can achieve greater depth and breadth in implementing evidenced-based infection control practices.

Electronic surveillance systems in infection prevention: organizational support, program characteristics, and user satisfaction

BACKGROUND

The use of electronic surveillance systems (ESSs) is gradually increasing in infection prevention and control programs. Little is known about the characteristics of hospitals that have a ESS, user satisfaction with ESSs, and organizational support for implementation of ESSs.

METHODS

A total of 350 acute care hospitals in California were invited to participate in a Web-based survey; 207 hospitals (59%) agreed to participate. The survey included a description of infection prevention and control department staff, where and how they spent their time, a measure of organizational support for infection prevention and control, and reported experience with ESSs.

RESULTS

Only 23% (44/192) of responding infection prevention and control departments had an ESS. No statistically significant difference was seen in how and where infection preventionists (IPs) who used an ESS and those who did not spend their time. The 2 significant predictors of whether an ESS was present were score on the Organizational Support Scale (odds ratio [OR], 1.10; 95% confidence interval [CI], 1.02-1.18) and hospital bed size (OR, 1.004; 95% CI, 1.00-1.007). Organizational support also was positively correlated with IP satisfaction with the ESS, as measured on the Computer Usability Scale (P = .02).

CONCLUSION

Despite evidence that such systems may improve efficiency of data collection and potentially improve patient outcomes, ESSs remain relatively uncommon in infection prevention and control programs. Based on our findings, organizational support appears to be a major predictor of the presence, use, and satisfaction with ESSs in infection prevention and control programs.

The electronic medical record as a tool for infection surveillance: successful automation of device-days

BACKGROUND

Manual collection of central venous catheter, ventilator, and indwelling urinary catheter device-days is time-consuming, often restricted to intensive care units (ICU) and prone to error.

METHODS

We describe the use of an electronic medical record to extract existing clinical documentation of invasive devices. This allowed automated device-days calculations for device-associated infection surveillance in an acute care setting.

RESULTS

The automated system had high sensitivity, specificity, and positive and negative predictive values (>0.90) compared with chart review. The system is not restricted to ICUs and reduces surveillance efforts by a conservative estimate of over 3.5 work-weeks per year in our setting. Eighty percent of urinary catheter days and 50% of central venous catheter-days occurred outside the ICU.

CONCLUSION

Device-days may be automatically extracted from an existing electronic medical record with a higher degree of accuracy than manual collection while saving valuable personnel resources.

Economics of infection control surveillance technology: cost-effective or just cost?

BACKGROUND

Previous studies have suggested that informatics tools, such as automated alert and decision support systems, may increase the efficiency and quality of infection control surveillance. However, little is known about the cost-effectiveness of these tools.

METHODS

We focus on 2 types of economic analyses that have utility in assessing infection control interventions (cost-effectiveness analysis and business-case analysis) and review the available literature on the economics of computerized infection control surveillance systems.

RESULTS

Previous studies on the effectiveness of computerized infection control surveillance have been limited to assessments of whether these tools increase the sensitivity and specificity of surveillance over traditional methods. Furthermore, we identified only 2 studies that assessed the costs associated with computerized infection control surveillance. Thus, it remains unknown whether computerized infection control surveillance systems are cost-effective and whether use of these systems improves patient outcomes.

CONCLUSION

The existing data are insufficient to allow for a summary conclusion on the cost-effectiveness of infection control surveillance technology. All future studies of computerized infection control surveillance systems should aim to collect outcomes and economic data to inform decision making and assist hospitals with completing business-cases analyses.

Implementation of a novel on-ward computer-assisted surveillance system for device-associated infections in an intensive care unit

For the presented study a computer-based surveillance system for detecting nosocomial infections (NI) with direct data input from attending on-ward physicians was implemented. During a 12-month period surveillance of ventilator-associated pneumonia (VAP) and catheter-associated bloodstream infections (BSI) was performed prospectively by on-ward physicians guided by infection control specialists on an 11-bed medical intensive care unit in a German university hospital. In 603 patients 3282 patient days were assessed. Completeness of data entry during the routine phase was 94% for ventilator days and 88% for central venous catheter days. The concordance of infection detection by automated evaluation and evaluation based clinical considerations was fairly good and was quantified by kappa measures of 0.49 for VAP and 0.57 for BSI. Detected infection rates ranged within the German national reference data. Personnel costs for on-ward physicians and infection control personnel were 1.01 Euro per device day in the routine phase. Time expenditure of less than 3 min per device day, rendered in about equal parts by physicians and infection control personnel, was lower than in studies relying on on-ward assessment by infection control personnel.

Comparison of automated strategies for surveillance of nosocomial bacteremia

OBJECTIVE

Surveillance of nosocomial bloodstream infection (BSI) is recommended, but time-consuming. We explored strategies for automated surveillance.

METHODS

Cohort study. We prospectively processed microbiological and administrative patient data with computerized algorithms to identify contaminated blood cultures, community-acquired BSI, and hospital-acquired BSI and used algorithms to classify the latter on the basis of whether it was a catheter-associated infection. We compared the automatic classification with an assessment (71% prospective) of clinical data.

SETTING

An 850-bed university hospital.

PARTICIPANTS

All adult patients admitted to general surgery, internal medicine, a medical intensive care unit, or a surgical intensive care unit over 3 years.

RESULTS

The results of the automated surveillance were 95% concordant with those of classical surveillance based on the assessment of clinical data in distinguishing contamination, community-acquired BSI, and hospital-acquired BSI in a random sample of 100 cases of bacteremia. The two methods were 74% concordant in classifying 351 consecutive episodes of nosocomial BSI with respect to whether the BSI was catheter-associated. Prolonged episodes of BSI, mostly fungemia, that were counted multiple times and incorrect classification of BSI clinically imputable to catheter infection accounted for 81% of the misclassifications in automated surveillance. By counting episodes of fungemia only once per hospital stay and by considering all cases of coagulase-negative staphylococcal BSI to be catheter-related, we improved concordance with clinical assessment to 82%. With these adjustments, automated surveillance for detection of catheter-related BSI had a sensitivity of 78% and a specificity of 93%; for detection of other types of nosocomial BSI, the sensitivity was 98% and the specificity was 69%.

CONCLUSION

Automated strategies are convenient alternatives to manual surveillance of nosocomial BSI.

Surveillance and infection control in an intensive care unit

OBJECTIVE

To evaluate the effect of an infection control program on the incidence of hospital-acquired infection (HAI) and associated mortality.

DESIGN

Prospective study.

SETTING

A 2000-bed, university-affiliated hospital in Italy.

PATIENTS

All patients admitted to the general intensive care unit (ICU) for more than 48 hours between January 2000 and December 2001.

METHODS

The infection control team (ICT) collected data on the following from all patients: demographics, origin, diagnosis, severity score, underlying diseases, invasive procedures, HAI, isolated microorganisms, and antibiotic susceptibility.

INTERVENTIONS

Regular ICT surveillance meetings were held with ICU personnel. Criteria for invasive procedures, particularly central venous catheters (CVCs), were modified. ICU care was restricted to a team of specialist physicians and nurses and ICU antimicrobial therapy policies were modified.

RESULTS

Five hundred thirty-seven patients were included in the study (279 during 2000 and 258 in 2001). Between 2000 and 2001, CVC exposure (82.8% vs 71.3%; P < .05) and mechanical ventilation duration (11.2 vs 9.6 days) decreased. The HAI rate decreased from 28.7% in 2000 to 21.3% in 2001 (P < .05). The crude mortality rate decreased from 41.2% in 2000 to 32.9% in 2001 (P < .05). The most commonly isolated microorganisms were nonfermentative gram-negative organisms and staphylococci (particularly MRSA). Mortality was associated with infection (relative risk, 2.11; 95% confidence interval, 1.72-2.59; P < .05).

CONCLUSION

Routine surveillance for HAI, coupled with new measures to prevent infections and a revised policy for antimicrobial therapy, was associated with a reduction in ICU HAls and mortality.

Preliminary assessment of an automated surveillance system for infection control

BACKGROUND AND OBJECTIVE

Rapid identification and investigation of potential outbreaks is key to limiting transmission in the healthcare setting. Manual review of laboratory results remains a cumbersome, time-consuming task for infection control practitioners (ICPs). Computer-automated techniques have shown promise for improving the efficiency and accuracy of surveillance. We examined the use of automated control charts, provided by an automated surveillance system, for detection of potential outbreaks.

SETTING

A 656-bed academic medical center.

METHODS

We retrospectively reviewed 13 months (November 2001 through November 2002) of laboratory-patient data, comparing an automated surveillance application with standard infection control practices. We evaluated positive predictive value, sensitivity, and time required to investigate the alerts. An ICP created 75 control charts. A standardized case investigation form was developed to evaluate each alert for the likelihood of nosocomial transmission based on temporal and spatial overlap and culture results.

RESULTS

The 75 control charts were created in 75 minutes and 18 alerts fired above the 3-sigma level. These were independently reviewed by an ICP and associate hospital epidemiologist. The review process required an average of 20 minutes per alert and the kappa score between the reviewers was 0.82. Eleven of the 18 alerts were determined to be potential outbreaks, yielding a positive predictive value of 0.61. Routine surveillance identified 5 of these 11 alerts during this time period.

CONCLUSION

Automated surveillance with user-definable control charts for cluster identification was more sensitive than routine methods and is capable of operating with high specificity and positive predictive value in a time-efficient manner.

Validation of a multicenter computer-based surveillance system for hospital-acquired bloodstream infections in neonatal intensive care departments

Automated systems can facilitate surveillance for health care-associated infections. The New York Antimicrobial Resistance Project (NYARP) electronically monitors trends in bloodstream infections from 6 medical centers in New York, NY. To validate NYARP's data, episodes of health care-associated bloodstream infections detected by this system were compared with those obtained by an infection control practitioner performing an unrelated study in 2 participating neonatal intensive care departments. The sensitivity (84%), specificity (99%), and positive (84%) and negative (99%) predictive values of NYARP were excellent when coagulase-negative staphylococcal bloodstream infections were removed.