Surveillance of hospital-acquired infection in England, Germany, and The Netherlands: will international comparison of rates be possible?

A computerized indicator for surgical site infection (SSI) assessment after total hip or total knee replacement: The French ISO-ORTHO indicator

OBJECTIVE

The French National Authority for Health (HAS), with a multidisciplinary working group, developed an indicator 'ISO-ORTHO' to assess surgical site infections (SSIs) after total hip arthroplasty or total knee arthroplasty (THA/TKA) based on the hospital discharge database. We present the ISO-ORTHO indicator designed for SSI automated detection and its relevance for quality improvement and hospital benchmarks.

METHODS

The algorithm is based on a combination of International Statistical Classification of Diseases, Tenth Revision (ICD-10) and procedure codes of the hospital stay. The target population was selected among adult patients who had a THA or TKA between January 1, 2017, and September 30, 2017. Patients at very high risk of SSI and/or with SSI not related to hospital care were excluded. We searched databases for SSIs up to 3 months after THA/TKA. The standardized infection ratio (SIR) of observed versus expected SSIs was calculated (logistic regression) and displayed as funnel plot with 2 and 3 standard deviations (SD) after adjustment for 13 factors known to increase SSI risk.

RESULTS

In total, 790 hospitals and 139,926 THA/TKA stays were assessed; 1,253 SSI were detected in the 473 included hospitals (incidence, 0.9%: 1.0% for THA, 0.80% for TKA). The SSI rate was significantly higher in males (1.2%), in patients with previous osteo-articular infection (4.4%), and those with cancer (2.3%), obesity, or diabetes. Most hospitals (89.9%) were within 2 SD; however, 12 hospitals were classified as outliers at more than +3 SD (1.6% of facilities), and 59 hospitals (7.9%) were outliers between +2 SD and +3 SD.

CONCLUSION

ISO-ORTHO is a relevant indicator for automated surveillance; it can provide hospitals a metric for SSI assessment that may contribute to improving patient outcomes.

The Minimum Data Set and Quality Indicators for National Healthcare-Associated Infection Surveillance in Mainland China: Towards Precision Management

The magnitude and scope of the healthcare-associated infections (HCAIs) burden are underestimated worldwide, and have raised public concerns for their adverse effect on patient safety. In China, HCAIs still present an unneglected challenge and economic burden in recent decades. With the purpose of reducing the HCAI prevalence and enhancing precision management, China's National Nosocomial Infection Management and Quality Control Center (NNIMQCC) had developed a Minimum Data Set (MDS) and corresponding Quality Indicators (QIs) for establishing national HCAI surveillance system, the data elements of which were repeatedly discussed, investigated, and confirmed by consensus of the expert team. The total number of data elements in MDS and QIs were 70 and 64, and they were both classified into seven categorical items. The NNIMQCC also had started two pilot projects to inspect the applicability, feasibility, and reliability of MDS. After years of hard work, more than 400 health facilities in 14 provinces have realized the importance of HCAI surveillance and contributed to developing an ability of exporting automatically standardized data to meet the requirement of MDS and participate in the regional surveillance system. Generally, the emergence of MDS and QIs in China indicates the beginning of the national HCAI surveillance based on information technology and computerized process data. The establishment of MDS aimed to use electronic health process data to ensure the data accuracy and comparability and to provide instructive and ongoing QIs to estimate and monitor the burden of HCAIs, and to evaluate the effects of interventions and direct health policy decision-making.

Key features of bone and joint infections following the implementation of reference centers in France

OBJECTIVES

French reference centers for bone and joint infections (BJI) were implemented from 2009 onwards to improve the management of complex BJIs. This study compared BJI burden before and after the implementation of these reference centers.

PATIENTS AND METHODS

BJI hospital stays were selected from the 2008 and 2013 national hospital discharge database using a validated algorithm, adding the new complex BJI code created in 2011. Epidemiology and economic burden were assessed.

RESULTS

BJI prevalence increased in 2013 (70 vs. 54/100,000 in 2008). Characteristics of BJI remained similar between 2008 and 2013: septic arthritis (50%), increasing prevalence with age and sex, case fatality 5%, mean length of stay 17.5 days, rehospitalization 20%. However, device-associated BJIs increased (34 vs. 26%) as well as costs (€421 million vs. €259 in 2008). Similar device-associated BJI characteristics between 2008 and 2013 were: septic arthritis (70%), case fatality (3%), but with more hospitalizations in reference centers (34 vs. 30%) and a higher cost per stay. Among the 7% of coded complex BJIs, the mean length of stay was 22.2 days and mean cost was €11,960.

CONCLUSIONS

BJI prevalence highly increased in France. Complex BJI prevalence assessment is complicated by the absence of clinical consensus and probable undercoding. A validation of clinical case definition of complex BJI is required.

Clinical relevance and effect of surgical wound classification in appendicitis: Retrospective evaluation of wound classification discrepancies between surgeons, Swissnoso-trained infection control nurse, and histology as well as surgical site infection rates by wound class

BACKGROUND

Surgical wound classification (SWC) is used for risk stratification of surgical site infection (SSI) and serves as the basis for measuring quality of care. The objective was to examine the accuracy and reliability of SWC. This study was purposed to evaluate the discrepancies in SWC as assessed by three groups: surgeons, an infection control nurse, and histopathologic evaluation. The secondary aim was to compare the risk-stratified SSI rates using the different SWC methods for 30 d postoperatively.

METHODS

An analysis was performed of the appendectomies from January 2013 to June 2014 in the Cantonal Hospital of Schaffhausen. SWC was assigned by the operating surgeon at the end of the procedure and retrospectively reviewed by a Swissnoso-trained infection control nurse after reading the operative and pathology report. The level of agreement among the three different SWC assessment groups was determined using kappa statistic. SSI rates were analyzed using a chi-square test.

RESULTS

In 246 evaluated cases, the kappa scores for interrater reliability among the SWC assessments across the three groups ranged from 0.05 to 0.2 signifying slight agreement between the groups. SSIs were more frequently associated with trained infection control nurse-assigned SWC than with surgeons based SWC.

CONCLUSIONS

Our study demonstrated a considerable discordance in the SWC assessments performed by the three groups. Unfortunately, the currently practiced SWC system suffers from ambiguity in definition and/or implementation of these definitions is not clearly stated. This lack of reliability is problematic and may lead to inappropriate comparisons within and between hospitals and surgeons.

Quality Assessment of Hospital Discharge Database for Routine Surveillance of Hip and Knee Arthroplasty–Related Infections

Objective.

Surgical site infection (SSI) surveillance represents a key method of nosocomial infection control programs worldwide. However, most SSI surveillance systems are considered to be poorly cost effective regarding human and economic resources required for data collection and patient follow up. This study aims to assess the efficacy of using hospital discharge databases (HDDs) as a routine surveillance system for detecting hip or knee arthroplasty–related infections (HKAIs).

Methods.

A case-control study was conducted among patients hospitalized in the Centre region of France between 2008 and 2010. HKAI cases were extracted from the HDD with various algorithms based on the International Classification of Diseases, Tenth Revision, and procedure codes. The control subjects were patients with hip or knee arthroplasty (HKA) without infection selected at random from the HDD during the study period. The gold standard was medical chart review. Sensitivity (Se), specificity (Spe), positive predictive value (PPV), and negative predictive value (NPV) were calculated to evaluate the efficacy of the surveillance system.

Results.

Among 18,265 hospital stays for HKA, corresponding to 17,388 patients, medical reports were checked for 1,010 hospital stays (989 patients). We identified 530 cases in total (incidence rate, 1% [95% confidence interval (CI), 0.4%–1.6%), and 333 cases were detected by routine surveillance. As compared with 480 controls, Se was 98%, Spe was 71%, PPV was 63%, and NPV was 99%. Using a more specific case definition, based on a sample of 681 hospital stays, Se was 97%, Spe was 95%, PPV was 87%, and NPV was 98%.

Conclusions.

This study demonstrates the potential of HDD as a tool for routine SSI surveillance after low-risk surgery, under conditions of having an appropriate algorithm for selecting infections.

Infect Control Hosp Epidemiol 2014;35(6):646–651

Healthcare-associated infections in Australia: time for national surveillance

OBJECTIVE

Healthcare-associated infection (HAI) surveillance programs are critical for infection prevention. Australia does not have a comprehensive national HAI surveillance program. The purpose of this paper is to provide an overview of established international and Australian statewide HAI surveillance programs and recommend a pathway for the development of a national HAI surveillance program in Australia.

METHODS

This study examined existing HAI surveillance programs through a literature review, a review of HAI surveillance program documentation, such as websites, surveillance manuals and data reports and direct contact with program representatives.

RESULTS

Evidence from international programs demonstrates national HAI surveillance reduces the incidence of HAIs. However, the current status of HAI surveillance activity in Australian states is disparate, variation between programs is not well understood, and the quality of data currently used to compose national HAI rates is uncertain.

CONCLUSIONS

There is a need to develop a well-structured, evidence-based national HAI program in Australia to meet the increasing demand for validated reliable national HAI data. Such a program could be leveraged off the work of existing Australian and international programs.

Process quality indicators in family medicine: results of an international comparison

Background

The aim of our study was to describe variability in process quality in family medicine among 31 European countries plus Australia, New Zealand, and Canada. The quality of family medicine was measured in terms of continuity, coordination, community orientation, and comprehensiveness of care.

Methods

The QUALICOPC study (Quality and Costs of Primary Care in Europe) was carried out among family physicians in 31 European countries (the EU 27 except for France, plus Macedonia, Iceland, Norway, Switzerland, and Turkey) and three non-European countries (Australia, Canada, and New Zealand). We used random sampling when national registers of practitioners were available. Regional registers or lists of facilities were used for some countries.

A standardized questionnaire was distributed to the physicians, resulting in a sample of 6734 participants. Data collection took place between October 2011 and December 2013. Based on completed questionnaires, a three-dimensional framework was established to measure continuity, coordination, community orientation, and comprehensiveness of care. Multilevel linear regression analysis was performed to evaluate the variation of quality attributable to the family physician level and the country level.

Results

None of the 34 countries in this study consistently scored the best or worst in all categories. Continuity of care was perceived by family physicians as the most important dimension of quality. Some components of comprehensiveness of care, including medical technical procedures, preventive care and health care promotion, varied substantially between countries. Coordination of care was identified as the weakest part of quality. We found that physician-level characteristics contributed to the majority of variation.

Conclusions

A comparison of process quality indicators in family medicine revealed similarities and differences within and between countries. The researchers found that the major proportion of variation can be explained by physicians’ characteristics.

Electronic supplementary material

The online version of this article (doi:10.1186/s12875-015-0386-7) contains supplementary material, which is available to authorized users.

Surgical Site Infection After Primary Hip and Knee Arthroplasty: A Cohort Study Using a Hospital Database

BACKGROUND

Hip or knee arthroplasty infection (HKAI) leads to heavy medical consequences even if rare.

OBJECTIVE

To assess the routine use of a hospital discharge detection algorithm of prosthetic joint infection as a novel additional tool for surveillance.

METHODS

A historic 5-year cohort study was built using a hospital database of people undergoing a first hip or knee arthroplasty in 1 French region (2.5 million inhabitants, 39 private and public hospitals): 32,678 patients with arthroplasty code plus corresponding prosthetic material code were tagged. HKAI occurrence was then tracked in the follow-up on the basis of a previously validated algorithm using International Statistical Classification of Disease, Tenth Revision, codes as well as the surgical procedures coded. HKAI density incidence was estimated during the follow-up (up to 4 years after surgery); risk factors were analyzed using Cox regression.

RESULTS

A total of 604 HKAI patients were identified: 1-year HKAI incidence was1.31%, and density incidence was 2.2/100 person-years in hip and 2.5/100 person-years in knee. HKAI occurred within the first 30 days after surgery for 30% but more than 1 year after replacement for 29%. Patients aged 75 years or older, male, or having liver diseases, alcohol abuse, or ulcer sore had higher risk of infection. The inpatient case fatality in HKAI patients was 11.4%.

CONCLUSIONS

The hospital database method used to measure occurrence and risk factors of prosthetic joint infection helped to survey HKAI and could optimize healthcare delivery.

Infect Control Hosp Epidemiol 2015;36(10):1198–1207

A preliminary study for the development of indices and the current state of surgical site infections (SSIs) in Korea: the Korean Surgical Site Infection Surveillance (KOSSIS) program

Purpose

We aimed to develop an effective system for surgical site infection (SSI) surveillance and examine the current domestic state of SSIs for common abdominal surgeries in Korea.

Methods

The Korean Surgical Site Infection Surveillance (KOSSIS) program was developed as an SSI surveillance system. A prospective multicenter study in nine university-affiliated or general hospitals was conducted for patients who underwent gastrectomy, cholecystectomy, appendectomy, colectomy, or proctectomy between August 16 and September 30 in 2012. Patients were monitored for up to 30 days by combining direct observation and a postdischarge surgeon survey. Data on SSIs were prospectively collected with KOSSIS secretarial support according to a common protocol. Operation-specific SSI rates were stratified according to risk factors and compared with data from the Korean Nosocomial Infections Surveillance System (KONIS) and National Healthcare Safety Network. A focus group interview was conducted with participating hospitals for feedback.

Results

A total of 1,088 operations were monitored: 207 gastrectomies, 318 cholecystectomies, 270 appendectomies, 197 colectomies, and 96 proctectomies. Operation-specific SSI rates determined by the KOSSIS program were substantially higher than those found in KONIS (7.73% [95% confidence interval, 4.5%-12.3%] vs. 3.4% for gastrectomies, 10.15% [95% confidence interval, 6.1%-15.2%] vs. 4.0% for colectomy, and 13.5% [95% confidence interval, 7.4%-22.0%] vs. 4.2% for proctectomy).

Conclusion

Despite a short surveillance period and heterogenous group of hospitals, our results suggest that KOSSIS could be a useful program to enhance SSI surveillance in Korea.

Active prospective surveillance study with post-discharge surveillance of surgical site infections in Cambodia

Barriers to the implementation of the Centers for Disease Control and Prevention (CDC) guidelines for surgical site infection (SSI) surveillance have been described in resource-limited settings. This study aimed to estimate the SSI incidence rate in a Cambodian hospital and to compare different modalities of SSI surveillance. We performed an active prospective study with post-discharge surveillance. During the hospital stay, trained surveyors collected the CDC criteria to identify SSI by direct examination of the surgical site. After discharge, a card was given to each included patient to be presented to all practitioners examining the surgical site. Among 167 patients, direct examination of the surgical site identified a cumulative incidence rate of 14 infections per 100 patients. An independent review of medical charts presented a sensitivity of 16%. The sensitivity of the purulent drainage criterion to detect SSIs was 83%. After hospital discharge, 87% of the patients provided follow-up data, and nine purulent drainages were reported by a practitioner (cumulative incidence rate: 20%). Overall, the incidence rate was dependent on the surveillance modalities. The review of medical charts to identify SSIs during hospitalization was not effective; the use of a follow-up card with phone calls for post-discharge surveillance was effective.

Characterization of epidemiological surveillance systems for healthcare-associated infections (HAI) in the world and challenges for Brazil

Surveillance systems for healthcare-associated infections (HAI) are essential for planning actions in prevention and control. Important models have been deployed in recent decades in different countries. This study aims to present the historical and operational characteristics of these systems and discuss the challenges for Brazil. Various models around the world have drawn on the experience of the United States, which pioneered this process. In Brazil, several initiatives have been launched, but the country still lacks a full national information system on HAI, thus indicating the need to promote action strategies, strengthen the role of States in communication between the Federal and local levels, pursue a national plan to organize surveillance teams with the necessary technological infrastructure, besides updating the relevant legislation for dealing with these challenges. Such measures are essential in the Brazilian context for the unified surveillance of HAI, aimed at healthcare safety and quality.

Governmental surveillance system of healthcare-associated infection in Brazil


Objective: This study aimed to describe the structure of governmental surveillance systems for Healthcare Associated Infection (HAI) in the Brazilian Southeastern and Southern States. Method: A cross-sectional, descriptive and exploratory study, with data collection by means of two-phases: characterization of the healthcare structure and of the HAI surveillance system. Results: The governmental teams for prevention and control of HAI in each State ranged from one to six members, having at least one nurse. All States implemented their own surveillance system. The information systems were classified into chain (n=2), circle (n=4) or wheel (n=1). Conclusion: Were identified differences in the structure and information flow from governmental surveillance systems, possibly limiting a nationwide standardization. The present study points to the need for establishing minimum requirements in public policies, in order to guide the development of HAI surveillance systems.


Methodology of the Norwegian Surveillance System for Healthcare-Associated Infections: the value of a mandatory system, automated data collection, and active postdischarge surveillance

BACKGROUND

Surveillance is a primary component of systems for the prevention of health care-associated infections (HCAI). Feedback to surgeons from these surveillance systems may reduce rates of surgical site infections (SSIs) by approximately 20%.

OBJECTIVE

Our objective was to describe the Norwegian Surveillance System for Healthcare-Associated Infections' (NOIS) module for SSI (NOIS-SSI) and to evaluate the completeness of hospital participation, the effectiveness of automated data collection, and the added value of follow-up after hospital discharge during 2005 to 2009.

METHODS

NOIS was introduced by regulation in 2005. Hospital participation is described through adherence to the mandatory requirements and participation in the voluntary aspects of the system. Automated data collection is evaluated through the completeness of reporting of explanatory and administrative variables. The impact of active postdischarge surveillance is assessed through the completeness of follow-up and the proportion of infections detected after hospital discharge.

RESULTS

The system has achieved 95% (52/55) hospital participation, with 65% (34/52) of the hospitals submitting more data than the required minimum. The completeness of patient and procedure-related background data is satisfactory, with 23.3% (5,079/21,772) of the records having at least 1 missing value. The completeness of 30-day follow-up of patients is 90.7% (19,747/21,772), and 81% (765/948) of the infections were detected after discharge from hospital.

CONCLUSION

Implementation of a new surveillance system for SSI has been successful evaluated through hospital participation, the completeness of reporting of explanatory and administrative variables, and the completeness of postdischarge follow-up. Important success factors are a mandatory system, automated data-harvesting systems in hospitals, and active postdischarge surveillance.

Surveillance length and validity of benchmarks for central line-associated bloodstream infection incidence rates in intensive care units

Introduction

Several national and regional central line-associated bloodstream infections (CLABSI) surveillance programs do not require continuous hospital participation. We evaluated the effect of different hospital participation requirements on the validity of annual CLABSI incidence rate benchmarks for intensive care units (ICUs).

Methods

We estimated the annual pooled CLABSI incidence rates for both a real regional (<100 ICUs) and a simulated national (600 ICUs) surveillance program, which were used as a reference for the simulations. We simulated scenarios where the annual surveillance participation was randomly or non-randomly reduced. Each scenario's annual pooled CLABSI incidence rate was estimated and compared to the reference rates in terms of validity, bias, and proportion of simulation iterations that presented valid estimates (ideal if≥90%).

Results

All random scenarios generated valid CLABSI incidence rates estimates (bias −0.37 to 0.07 CLABSI/1000 CVC-days), while non-random scenarios presented a wide range of valid estimates (0 to 100%) and higher bias (−2.18 to 1.27 CLABSI/1000 CVC-days). In random scenarios, the higher the number of participating ICUs, the shorter the participation required to generate ≥90% valid replicates. While participation requirements in a countrywide program ranged from 3 to 13 surveillance blocks (1 block = 28 days), requirements for a regional program ranged from 9 to 13 blocks.

Conclusions

Based on the results of our model of national CLABSI reporting, the shortening of participation requirements may be suitable for nationwide ICU CLABSI surveillance programs if participation months are randomly chosen. However, our regional models showed that regional programs should opt for continuous participation to avoid biased benchmarks.

Building a benchmark through active surveillance of intensive care unit-acquired infections: the Italian network SPIN-UTI

The Italian Nosocomial Infections Surveillance in Intensive Care Units (ICUs) (SPIN-UTI) project of the Italian Study Group of Hospital Hygiene (GISIO - SItI) was undertaken to ensure standardisation of definitions, data collection and reporting procedures using the Hospital in Europe Link for Infection Control through Surveillance (HELICS)-ICU benchmark. Before starting surveillance, participant ICUs met in order to involve the key stakeholders in the project through participation in planning. Four electronic data forms for web-based data collection were designed. The six-month patient-based prospective survey was undertaken from November 2006 to May 2007, preceded by a one-month surveillance pilot study to assess the overall feasibility of the programme and to determine the time needed and resources for participant hospitals. The SPIN-UTI project included 49 ICUs, 3053 patients with length of stay >2 days and 35 498 patient-days. The cumulative incidence of infections was 19.8 per 100 patients and the incidence density was 17.1 per 1000 patient-days. The most frequently encountered infection type was pneumonia, Pseudomonas aeruginosa being the most frequent infection-associated micro-organism, followed by Staphylococcus aureus and Acinetobacter baumannii. Site-specific infection rates for pneumonia, bloodstream infections, central venous catheter-related bloodstream infections and urinary tract infections, stratified according to patient risk factors, were below the 75th centile reported by the HELICS network benchmark. The SPIN-UTI project showed that introduction of ongoing surveillance should be possible in many Italian hospitals. The study provided the opportunity to participate in the HELICS project using benchmark data for comparison and for better understanding of factors influencing risks.

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.

Use of anti-infective serial prevalence studies to identify and monitor hospital-acquired infection

We developed the 'Pragmatic Proxy Protocol' (PPP) to estimate the prevalence of hospital-acquired infection (HAI) by integrating our existing pharmacy serial point prevalence studies of anti-infective prescribing practices with electronic data on microbiological and radiographic markers of infection. Our method was evaluated against the standard Hospital Infection Society/Infection Control Nurses Association Protocol (HIP). In the non-surgical patients, PPP has a sensitivity of 1.00 [confidence interval (CI): 0.70-1.00] and specificity of 0.97 (CI: 0.93-0.99). PPP suggests that for non-surgical patients, the prevalence of HAI using HIP could be underestimated by 42%. PPP takes about two-thirds of the time of HIP (75 vs 106 h) and is at least one-third cheaper. It could easily be adapted to advances in electronic reporting and, with the development of Anti-infective Care Bundles, would increase its sensitivity for the detection of HAI in surgical patients. PPP could be used to increase the frequency of routine HAI surveillance to determine the overall burden of infection and assess the efficacy of intervention strategies in a timely manner allowing rapid, direct feedback and engagement with clinicians.

Comparison of the National Surgical Site Infection surveillance data between The Netherlands and Germany: PREZIES versus KISS

As there has been increasing interest in comparing surgical site infection (SSI) rates between countries, we compared the SSI surveillance data for The Netherlands ('PREZIES') and Germany ('KISS'). Both surveillance systems have comparable protocols with many similar risk factors, including SSI definitions developed by the Centers for Disease Control and Prevention and optional postdischarge surveillance. Nine surgical procedure categories from several specialities were included, the reporting of which were similar, with respect to content and with enough data for proper comparison. Differences for the SSI data were found between PREZIES and KISS for duration of surgery, wound contamination class, American Society of Anesthesiologists physical status classification and the postoperative duration of hospitalization. A significantly higher superficial SSI rate was found for seven surgical procedures according to PREZIES and a higher deep SSI rate for five procedures. When considering only deep SSI during hospitalization, the differences in SSI rates were much smaller. Differences in intensity of postdischarge surveillance led to 34% of SSI being detected after discharge for PREZIES and 21% for KISS. In conclusion, even though similar infection surveillance protocols are used in The Netherlands and Germany, differences occurred in the implementation. Comparisons between countries are most reliable if only deep SSIs during hospitalization are taken into account, since these SSI are not affected by postdischarge surveillance and the diagnostic sensitivity for deep SSI is probably more alike between countries than for superficial SSI.

European perspective on surveillance

International comparisons yield interesting insights regarding quality of care, beyond the field of healthcare-associated infection (HAI) prevention. Therefore, the exchange of experiences of national surveillance systems should be encouraged. However, the interpretation of differences of HAI rates should be made very carefully. Differences in healthcare systems, legal and cultural aspects, as well as differences in the methods of the surveillance systems, may have an enormous influence. One of the most crucial aspects of surveillance data is their validity, therefore it would be very helpful to combine the experience of all European validation studies performed in order to develop a protocol for a meaningful and cost-effective method for performing validation studies. Meanwhile some national surveillance systems have shown their effectiveness with reductions of 24 57% for surgical site infections (SSIs) and 20 29% for HAI in ICUs. Today, mandatory public reporting is probably the most demanding problem for the national HAI surveillance systems in Europe. The exchange of experience between the European surveillance networks in this respect in particular--remains a cornerstone and will motivate further activities in the individual countries.

Device-associated nosocomial infection rates in intensive care units in Greece

Site-specific, risk-adjusted incidence rates of intensive care unit (ICU)-acquired infections were obtained through standardized surveillance in 8 ICUs in Greece. High rates were observed for central line-associated bloodstream infection (12.1 infections per 1,000 device-days) and ventilator-associated pneumonia (12.5 infections per 1,000 device-days). Gram-negative microorganisms accounted for 60.4% of the isolates recovered, and Acinetobacter species were predominant. To reduce infection rates in Greek ICUs, comprehensive infection control programs are required.

The first prevalence survey of nosocomial infections in the University Hospital Centre 'Mother Teresa' of Tirana, Albania

A survey was conducted in the largest hospital in Albania to estimate the prevalence and risk factors for nosocomial infections (NIs). A one-day prevalence survey was carried out between October and November 2003 in medical, surgical and intensive care wards. Centers for Disease Control and Prevention definitions were used. Study variables included patient and hospital characteristics, surgical procedures, invasive devices, antibiotic treatment, microbiological and radiological examinations, infection signs and symptoms. Risk factors were determined using logistic regression. In all, 185 NIs were found in 163 of 968 enrolled patients. Urinary tract infections (33.0%), surgical site infections (24.3%), pneumonia (13.0%) and venous infections (9.2%) were the most frequent NIs. The prevalence of NIs was higher in intensive care units (31.6%) than in surgical (22.0%) and medical wards (10.3%). Overall, 132 NIs (71.4%) were confirmed by microbiological examination; the single most frequently isolated micro-organism was Staphylococcus aureus (18.2%). By means of logistic regression, the following independent risk factors were identified: age >40 years, length of hospital stay, 'trauma' diagnosis at admission, and invasive devices. Even though comparisons must be made with great caution, the prevalence of NIs was higher than in western European countries and in some developing countries.

Impact of postdischarge surveillance on the rate of surgical site infection after orthopedic surgery

OBJECTIVE

To evaluate the impact of postdischarge surveillance on surgical site infection (SSI) rates after orthopedic surgery.

SETTING

Nine hospitals participating in the Finnish Hospital Infection Program.

PATIENTS

All patients who underwent hip or knee arthroplasty or open reduction of a femur fracture during 1999-2002.

RESULTS

The date of discharge was available for 11,812 procedures (90%). The median length of hospital stay was 8 days (range per hospital, 6-9 days). The overall SSI rate was 3.3% (range, 0.8%-6.4%). Of 384 SSIs detected, 216 (56%; range, 28%-90%) were detected after discharge: 93 (43%) were detected on readmission to the hospital, 73 (34%) at completion of a postdischarge questionnaire, and 23 (11%) at a follow-up visit. For 27 postdischarge SSIs (13%), the location of detection was unknown. Altogether, 32 (86%) of 37 of organ/space SSIs, 57 (80%) of 71 deep incisional SSIs, and 127 (46%) of 276 superficial incisional SSIs were detected after discharge. Most SSIs (70%) detected on readmission were severe (organ/space or deep incisional), whereas most SSIs (86%) detected at follow-up visits or at completion of a postdischarge questionnaire were superficial. Of all SSIs, 78% (range, 48%-100%) were microbiologically confirmed. Microbiologic confirmation was less common after discharge than during postoperative hospital stay (66% vs 93%; P<.001).

CONCLUSIONS

Postdischarge surveillance had a large impact on the rate of SSI detected after orthopedic surgery. However, postdischarge surveillance conducted by means of a questionnaire detected only a minority of deep incisional and organ/space SSIs.

Improved risk adjustment for comparison of surgical site infection rates

OBJECTIVE

To develop prognostic models for improved risk adjustment in surgical site infection surveillance for 5 surgical procedures and to compare these models with the National Nosocomial Infection Surveillance system (NNIS) risk index.

DESIGN

In a multicenter cohort study, prospective assessment of surgical site infection and risk factors was performed from 1996 to 2000. In addition, risk factors abstracted from patient files, available in a national medical register, were used. The c-index was used to measure the ability of procedure-specific logistic regression models to predict surgical site infection and to compare these models with models based on the NNIS risk index. A c-index of 0.5 indicates no predictive power, and 1.0 indicates perfect predictive power.

SETTING

Sixty-two acute care hospitals in the Dutch national surveillance network for nosocomial infections.

PARTICIPANTS

Patients who underwent 1 of 5 procedures for which the predictive ability of the NNIS risk index was moderate: reconstruction of the aorta (n=875), femoropopliteal or femorotibial bypass (n=641), colectomy (n=1,142), primary total hip prosthesis (n=13,770), and cesarean section (n=2,962).

RESULTS

The predictive power of the new model versus the NNIS index was 0.75 versus 0.62 for reconstruction of the aorta (P<.01), 0.78 versus 0.58 for femoropopliteal or femorotibial bypass (P<.001), 0.69 versus 0.62 for colectomy (P<.001), 0.64 versus 0.56 for primary total hip prosthesis arthroplasty (P<.001), and 0.70 versus 0.54 for cesarean section (P<.001).

CONCLUSION

Data available from hospital information systems can be used to develop models that are better at predicting the risk of surgical site infection than the NNIS risk index. Additional data collection may be indicated for certain procedures--for example, total hip prosthesis arthroplasty.

Effectiveness of a nationwide nosocomial infection surveillance system for reducing nosocomial infections

In recent years, several countries have established surveillance systems for nosocomial infections (NIs) on a national basis. Limited information has been published on the effectiveness of these national surveillance systems. The aim of this study was to investigate whether participation in the German national NI surveillance system [Krankenhaus Infektions Surveillance System (KISS)] resulted in reduced rates of NIs. Three major NIs were studied: ventilator-associated pneumonia (VAP) and central-venous-catheter-related primary bloodstream infections (CR-BSIs) in intensive care units (ICUs), and surgical site infections (SSIs) in surgical inpatients. Data were collected from January 1997 until December 2003. Only institutions that had participated in KISS for at least 36 months were considered for analysis. Data from the first 12 months of surveillance were compared with data from the second and third 12-month periods. One hundred and fifty ICUs and 133 surgical departments fulfilled the inclusion criteria. In their first year of participation in KISS, the ICUs had an average VAP rate of 11.2 per 1000 ventilator-days and a CR-BSI rate of 2.1 per 1000 catheter-days. The average SSI rate in the surgical inpatients was 1.6 per 100 operations in their first year of participation. Comparing the infection rates in the third year with the first year, the relative risk (RR) for VAP was 0.71 [95% confidence intervals (CI) 0.66-0.76] and the RR for CR-BSI was 0.80 (95% CI 0.72-0.90). The corresponding RR for SSI was 0.72 [95% CI 0.64-0.80]. Participation in KISS was associated with a significant reduction in these three NIs.

Surveillance of nosocomial infections in a neurologic intensive care unit

OBJECTIVE

To assess data on the epidemiology of nosocomial infection (NI) among neurologic intensive care patients.

DESIGN

Prospective periodic surveillance study.

SETTING

An 8-bed neurologic intensive care unit (ICU).

PATIENTS

All those admitted for more than 24 hours during five 3-month periods between January 1999 and March 2003.

METHODS

Standardized surveillance within the German infection surveillance system.

RESULTS

Three hundred thirty-eight patients with a total of 2,867 patient-days and a mean length of stay of 8.5 days were enrolled during the 15-month study period. A total of 71 NIs were identified among 52 patients. Urinary tract infections (UTIs) were the most frequent NI (36.6%), followed by pneumonia (29.6%) and bloodstream infections (BSIs) (15.5%). The overall incidence and incidence density of NIs were 21.0 per 100 patients and 24.8 per 1,000 patient-days, respectively. Incidence densities were 9.8 UTIs per 1,000 urinary catheter-days (CI95, 6.4-14.4), 5.6 BSIs per 1,000 central venous catheter-days (CI9s, 2.8-10.0), and 12.8 cases of pneumonia per 1,000 ventilation-days (Cl95, 8.0-19.7). Device-associated UTI and pneumonia rates were in the upper range of national and international reference data for medical ICUs, despite the intensive infection control and prevention program in operation in the hospital.

CONCLUSION

Neurologic intensive care patients have relatively high rates of device-associated nosocomial pneumonia and UTI. For a valid comparison of surveillance data and implementation of targeted prevention strategies, we would strongly recommend provision of national benchmarks for the neurologic ICU setting.

Reduction of orthopaedic wound infections in 21 hospitals

INTRODUCTION

The German national nosocomial infections surveillance system (KISS) has been collecting surveillance data from hip and knee prosthesis operations since 1997. The purpose of this article is to investigate whether surveillance and feedback of surgical site infection (SSI) information to the physicians and nurses of participating hospitals lead to reduced SSI rates or not.

MATERIALS AND METHODS

Only information from hospitals previously participating for at least 3 years was used for the analysis. Monthly SSI rates were pooled over the 36-month period, beginning in each clinic's case with its first month of participation, the rates then being compared for 12-month periods. Relative risks were calculated for comparison of the SSI rates in the first and third years of participation. A multiple logistic regression analysis with stepwise variable selection was performed to identify significant risk factors, including the year of surveillance after starting surveillance activities.

RESULTS

The overall SSI rates were 1.4% for hip prosthesis and 1.0% for knee prosthesis. Fourteen clinics participated in KISS for at least 3 years continuously with HIP prostheses and 21 with knee prostheses. It was possible to include a total of 15,457 hip and 9,011 knee procedures for this analysis. A comparison of data from the first and the third years show a significant SSI reduction with hip procedures, with a relative risk of 0.54 (CI95 0.38-0.77), and a trend towards reduced SSI rates for knee procedures. The multiple logistic regression analysis confirmed that the SSI rate for hip prosthesis was significantly lower in the third year than in the first year of surveillance (OR = 0.57; CI95 0.42-0.78), though for knee prosthesis the level of significance was not achieved.

CONCLUSION

A reduction of SSIs following hip and knee prosthesis operations through the introduction of ongoing surveillance and the possibility of using benchmark data for comparison does seem to be possible in many institutions.

Adverse impact of surgical site infections in English hospitals

Between October 1997 and June 2001, 140 English hospitals participating in the surveillance of surgical site infection (SSI) with the Nosocomial Infection National Surveillance Service (NINSS) reported 2832 SSIs following 67 410 surgical procedures in nine defined categories of surgery. Limb amputation had the highest incidence of SSI with 14.3 SSIs per 100 operations. For all categories of surgery, except knee prosthesis (P=0.128), there was a linear increase in the incidence of SSI when the American National Nosocomial Infections Surveillance risk index increased. Superficial incisional SSI was more common than deep incisional and organ/space SSI, and accounted for more than half of all SSIs for all categories of surgery. The postoperative length of stay (LOS) was longer for patients with SSI, and when adjusted for other factors influencing LOS, the extra LOS due to SSI ranged from 3.3 days for abdominal hysterectomy to 21.0 days for limb amputation, and was at least nine days for the other categories. The additional cost attributable to SSI ranged from pound959 for abdominal hysterectomy to pound6103 for limb amputation. Deep incisional and organ/space SSI combined incurred a greater extra LOS and cost than superficial incisional SSI for all categories of surgery, except limb amputation. The crude mortality rate was higher for patients with SSI for all categories of surgery but, after controlling for confounding, only patients with SSI following hip prosthesis had a mortality rate that was significantly higher than those without SSI [odds ratio (OR)=1.8, P=0.002]. However, the adjusted mortality rate for patients with deep incisional and organ/space SSI compared with those without SSI was significantly higher for vascular surgery (OR=6.8, P<0.001), hip prosthesis (OR=2.5, P=0.005) and large bowel surgery (OR=1.8, P=0.04). This study shows that the adverse impact of SSI differs greatly for different categories of surgery, and highlights the importance of measuring the impact for defined categories rather than for all SSIs and all surgical procedures.

Estimation of methicillin-resistant Staphylococcus aureus transmission by considering colonization pressure at the time of hospital admission

Our objective was to evaluate the accuracy of a methicillin-resistant Staphylococcus aureus (MRSA) rate using the imported MRSA reservoir identified at the time of hospital admission. Two indicators were used: the number of imported MRSA patient-days/total number of patient-days [representing colonization pressure (CP) at the time of admission] and the incidence of hospital-acquired MRSA isolated from clinical samples expressed as density/100 patient-days for carriers identified at the time of admission [representing the incidence taking CP into account (ICP)]. The variations of these indicators were analysed and compared with two more common indicators: percentage of MRSA acquired in our hospital and the incidence of hospital-acquired MRSA isolated from clinical samples expressed as density/1000 patient-days within three four-month periods during 2002. Common indicators varied similarly, with marked decline during the third period; first-period CP was twice that of other periods (P<10(-6)) and the highest (>two-fold) ICP was seen in the summer (second) period (P<0.001) when the personnel/patient ratio was the lowest. Thus, comparison of different indicators within four-month periods underlines important differences between common and novel indicators. Despite several limitations, ICP should be helpful in the interpretation of MRSA surveillance data, particularly for estimating the extent of MRSA transmission.

Hospital infection control in Europe: evaluation of present practice and future goals

The objective of this study was to assess current infection control practice in Europe and its structure, future research priorities, and how infection control should be organised. A questionnaire was sent to 223 hospital infection control physicians throughout Europe, of whom 54 in 18 countries responded. With respect to future research priorities in infection control in Europe, the largest proportion (69%) of the infection control specialists sampled expressed the need for standardisation of surveillance systems for international comparison of nosocomial infection rates. The results of this survey might help to create a basis for standardised guidelines which take into account European-wide interests.

Surgical site infections in patients undergoing major operations in a university hospital: using standardized infection ratio as a benchmarking tool

BACKGROUND

Because patterns of infection acquired in patients undergoing operation are ever changing, it is an essential part of nosocomial infection surveillance programs to periodically document the epidemiologic features of infection in these patients. This study was conducted with the primary intention of describing the incidence and risk factors of the surgical site infection (SSI).

METHODS

We performed a prospective study in patients undergoing certain major operations at a 750-bed university hospital in Thailand. The National Nosocomial Infection Surveillance (NNIS) system method and criteria were used for identifying and diagnosing infection. The infection rates were benchmarked with the NNIS report by means of indirect standardization and reported in terms of standardized infection ratio. Risk factors for SSI were evaluated using the multiple logistic regression model.

RESULTS

From September 1998 to March 2000, the study included 4193 patients with 4437 major operations. The study identified 192 SSIs, 76 urinary catheter-related urinary tract infections, 26 central line-related bloodstream infections, and 39 instances of ventilator-associated pneumonia (VAP), yielding an infection rate of 4.3 SSIs/100 operations, 11.0 catheter-related urinary tract infections/1000 urinary catheter-days, 6.1 central line-related bloodstream infections/1000 central line-days, and 11.0 VAPs/1000 ventilator-days. When compared with data from NNIS, the standardized infection ratio of SSI, catheter-related urinary tract infection, central line-related bloodstream infection, and VAP were 2.3, 2.1, 1.1, and 0.8, respectively. The factors that significantly associated with SSI were duration of operation in minutes, American Society of Anesthesiologists (ASA) class, and degree of wound contamination.

CONCLUSION

All of the infection rates identified, except VAP, were higher than the average NNIS rates. The risk factors for SSI were prolonged duration of operation, poor physical status according to ASA classification, and higher degree of wound contamination.

Comparison of US and non-US central venous catheter infection rates: evaluation of processes and indicators in infection control study

OBJECTIVE

We sought to identify the presence or absence of international variation in central venous catheter-associated bloodstream infection (BSI) rates and to examine associated infection control practices that might underlie the differences.

DESIGN

The Evaluation of Processes and Indicators in Infection Control (EPIC) study was conducted as a prospective surveillance study.

SETTINGS

The study took place in intensive care units (ICUs) from 14 countries, which were from the Asian Pacific (3), Europe (7), Middle East (2), and South America (2), in addition to 41 US hospitals.

METHODS

We compared the National Nosocomial Infections Surveillance catheter-associated BSI rate between the non-US and US units. We also compared the following organization factors between the 2 groups: hospital factors (ownership, average daily census of patients); ICU type (medical vs surgical); number of beds; and infection control-related factors (number of staff, number of hours spent on study ICU surveillance, years of experience, number of inservice sessions on line infection, number of blood cultures drawn/1000 patients).

RESULTS

We found no significant difference in catheter-associated BSI rates between non-US and US hospitals (5.02 +/- 0.75 vs 3.82 +/- 0.42/1000 days, respectively; P =.27). Non-US hospitals were more likely to be government-owned (10/14 vs 7/41;P <.001) and to have larger daily patient census (795 +/- 84 vs 276 +/- 47 patients; P <.001). There was no difference in ICU type or number of beds. Infection control committees were present in all US and non-US hospitals. No significant differences were found in the number of staff involved in surveillance in the study ICU, years of experience, hours spent on surveillance, or the provision of inservices on line care. The use of barriers during line insertion also did not differ.

CONCLUSIONS

Catheter-associated BSIs in patients in the ICU were not significantly different between non-US and US hospitals. All hospitals had infection control committees, and there were no significant differences in time spent and numbers of persons involved in ICU surveillance activities. These findings suggest that many aspects of the standards of care do not differ between the 2 groups.

Device-related sources of bacteraemia in English hospitals--opportunities for the prevention of hospital-acquired bacteraemia

Between 1997 and 2001, 17 teaching and 56 non-teaching acute English hospitals conducted hospital-wide surveillance of hospital-acquired bacteraemia (HAB) using a standard protocol drawn up by the Nosocomial Infection National Surveillance Scheme (NINSS). The sources of organisms, the incidence of device-related HAB, and the distribution of HABs from individual device-related sources by specialty and type of hospital were determined for 6,956 HABs in order to identify where resources should best be targeted to reduce these infections. The overall incidence of HAB was higher in teaching than in non-teaching hospitals: 5.39 and 2.83 HABs per 1,000 patients at risk, respectively (P<0.001). Device-related sources were responsible for 52.4 and 43.2% of all HABs in teaching and non-teaching hospitals, respectively (P<0.001), and central lines were the commonest source, causing 38.3% of HABs in teaching versus 22.3% in non-teaching hospitals (P<0.001). In teaching hospitals, general intensive care units (ICUs), haematology, special care baby units (SCBUs), nephrology, and oncology accounted for only 6.1% of the population surveyed, but had the highest incidence of HAB, and contributed 47.8% of 2091 HABs and 56.9% of 1,095 device-related bacteraemias. Of 623 device-related bacteraemias in these high-risk specialties, 554 (88.9%) were from central lines. Thus, in teaching hospitals, resources should be targeted primarily at the prevention of central line-related bacteraemia in these five high-risk specialties, and the surveillance should include data on central line use. In non-teaching hospitals, nearly two thirds (63.3%) of 4,865 HABs and 60.7% of 2,103 device-related bacteraemias were from a few specialties with a low incidence of bacteraemia, but large numbers of patients, namely general medicine, general surgery, geriatric medicine and urology. These specialties accounted for 50.5% of the population surveyed. Central lines were the most common source of bacteraemia in general medicine and surgery, and together accounted for 23.3% of all device-related bacteraemias. However, in geriatric medicine and urology, central line sources were infrequent, accounting for only 1.7% of all device-related bacteraemias. On the other hand, bacteraemia from catheter-associated UTI were common in all these four specialties accounting for 20.9% of all device-related bacteraemias. Thus, in non-teaching hospitals, resources should be targeted primarily at these low-risk specialties and surveillance should include, at least, bacteraemia from central lines and from catheter-associated UTI. Further benefit can be obtained by including central line-related bacteraemias from general ICU and haematology patients, as they contributed 17.0% of all device-related bacteraemias in non-teaching hospitals.

A user evaluation of the Nosocomial Infection National Surveillance System: surgical site infection module

The Nosocomial Infection National Surveillance Scheme (NINSS) enables hospitals in England to undertake surveillance of healthcare associated infection, compare their results with national aggregated data, and use the information to improve patient care. A surgical site infection (SSI) module was introduced in 1997, and participation has increased steadily since its inception. This survey was undertaken to assess the views of users on the current service, and how the module should be developed to best meet their needs and resources. Survey forms were sent to infection control teams (ICTs) at the 113 hospitals that had participated at any time during the first three years of the programme. The response rate was 90% (102). The views of users were generally very positive and indicated considerable support for the approach to this type of surveillance. The ability to compare hospital infection rates with national data, the availability of standardized surveillance methods, and centralized data analysis and report production were key reasons for participation for over 80% of users. Most did not wish to see any major changes made to the protocol, although more than a third of users suggested additional data items. Overall, users were satisfied with both the content and timescale for receipt of feedback reports, and 77% disseminated them to at least three groups of clinicians and managers. The majority of ICTs (89%) gave the results directly to the surgeons. For some users (29%) it was too early to assess the value of the surveillance. Of the remainder, although results provided evidence of good performance for some, 46% identified high rates of SSI in one or more groups of surgical patients. In about two-thirds of these hospitals, a review or change in clinical practice was initiated as a result. Three main areas for development were identified: an extended range of surgical procedures, post-discharge surveillance and improved local data collection and analysis systems. Users said they would also like training in handling and interpreting surveillance data. These needs should be addressed in order to ensure the continuing success of national surveillance.

Surveillance in infection control: are we making progress?

PURPOSE OF THE REVIEW

Surveillance of nosocomial infections is an indispensable tool in infection control, and is used for detecting problem areas, defining patients who are at risk and evaluating intervention strategies. Surveillance techniques are continuously being evaluated and improved.

RECENT FINDINGS

Problems with definitions, risk stratification and case finding render development of (inter)national surveillance systems difficult with respect to the comparability of data between different hospitals. These problems also influence surveillance in specific areas of nosocomial infections, such as urinary tract infections, ventilator-associated pneumonia and surgical site infections. Examples of such problem areas are discussed in the present review.

SUMMARY

Despite continuing efforts made to improve quality of (inter)national and local surveillance systems, issues of infection definition and risk stratification are still under debate and need further research.