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H Rüden

Publications and source records attributed to H Rüden.

At least 19 recordsLinked to original sources

Reduction of surgical site infection rates associated with active surveillance.

OBJECTIVE: To evaluate whether surgical site infection (SSI) rates decrease in surgical departments as a result of performing active SSI surveillance. DESIGN: Retrospective multiple logistic regression analyses. SETTING: A group of 130 surgical departments of German hospitals participating in the Krankenhaus Infektions Surveillance System (KISS). METHODS: Data for 19 categories of operative procedures performed between January 1997 and June 2004 were included (119,114 operations). Active SSI surveillance was performed according to National Nosocomial Infections Surveillance system (NNIS) methods and definitions. Departments' SSI rates were calculated individually for each year of surveillance and for each operative procedure category, taking into account when the individual departments had begun their surveillance activities. Multiple logistic regression analyses on a single operation basis were carried out with stepwise variable selection to predict outcomes for patients with SSI. The variables included were as follows: the department's year of participation, NNIS risk index variables, patients' age and sex, and the hospitals' structural characteristics, such as yearly operation frequency, number of beds, and academic status. RESULTS: For 14 of 19 operative procedure categories analyzed, there was a tendency toward lower SSI rates that was associated with increasing duration of SSI surveillance. In multiple logistic regression analyses of pooled data for all operative procedures, the departments' participation in the surveillance system was a significant independent protective factor. Compared with the surveillance year 1, the SSI risk decreased in year 2 (odds ratio, 0.84; 95% confidence interval, 0.77-0.93) and in year 3 (odds ratio, 0.75; 95% confidence interval, 0.68-0.82), and there was no change in year 4. CONCLUSION: The SSI incidence was reduced by one quarter as a result of the surveillance-induced infection control efforts, which indicates the usefulness of a voluntary surveillance system.

Humans↗

Reduction of surgical site infections after Caesarean delivery using surveillance.

Since 1997, the Krankenhaus Infektions Surveillance System (KISS) has collected data on surgical site infections (SSIs) following Caesarean delivery (CD). The aim of this study was to determine whether surveillance and feedback of healthcare-associated infections (HAIs) could reduce the infection rate after CD. Only departments that had participated in KISS for at least three years were included in the analysis. The CD infection rates of the first, second and third years of KISS participation were compared for significant differences. The relative risk was calculated for the first and the third year of KISS participation. Multi-variate logistic regression analysis was performed to detect significant risk factors for SSI after CD using the third year of participation as one parameter. Twenty-six of 52 obstetric and gynaecology departments met the study's inclusion criteria. In those 26 departments, 17,405 CD procedures were performed and 331 SSIs were recorded (1.9%). The SSI rate after CD procedures was significantly reduced in the third year of KISS participation (1.6%) compared with the first year of KISS participation (2.4%), with a relative risk of 0.63 [95% confidence interval (CI) 0.48-0.82]. Logistic regression analysis confirmed that KISS participation over three years was an independent factor for the reduction of SSI rate (odds ratio 0.64; 95% CI 0.49-0.83). As shown previously for other types of HAI, this study demonstrated that continuous surveillance and comparison with stratified reference data could reduce SSI infection rates after CD.

Cesarean Section↗

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.

Bacteremia↗

Use of multistate models to assess prolongation of intensive care unit stay due to nosocomial infection.

BACKGROUND: Reliable data on the costs attributable to nosocomial infection (NI) are crucial to demonstrating the real cost-effectiveness of infection control measures. Several studies investigating this issue with regard to intensive care unit (ICU) patients have probably overestimated, as a result of inappropriate study methods, the part played by NIs in prolonging the length of stay. METHODS: Data from a prospective study of the incidence of NI in 5 ICUs over a period of 18 months formed the basis of this analysis. For describing the temporal dynamics of the data, a multistate model was used. Thus, ICU patients were counted as case patients as soon as an NI was ascertained on any particular day. All patients were then regarded as control subjects as long as they remained free of NI (time-to-event data analysis technique). RESULTS: Admitted patients (n=1,876) were observed for the development of NI over a period of 28,498 patient-days. In total, 431 NIs were ascertained during the study period (incidence density, 15.1 NIs per 1,000 patient-days). The influence of NI as a time-dependent covariate in a proportional hazards model was highly significant (P< .0001, Wald test). NI significantly reduced the discharge hazard (hazard ratio, 0.72 [95% confidence interval, 0.63-0.82])--that is, it prolonged the ICU stay. The mean prolongation of ICU length of stay due to NI (+/- standard error) was estimated to be 5.3+/-1.6 days. CONCLUSIONS: Further studies are required to enable comparison of data on prolongation of ICU length of stay with the results of various study methods.

Aged↗

[Responsibility of surgeons for surgical site infections].

Surgical site infections can be traced to discrepancies in one specific hospital department: the operating suite. Therefore, prevention is often viewed as resting completely on the surgeon. However, the source of micro-organisms responsible for surgical site infections can be endogenous or exogenous. Most infections are believed to be the former, i.e. caused by micro-organisms already resident in the patient's body. Therefore the surgeon can be regarded as suspect only in exceptional cases and usually himself a victim. Prevention is possible not only for exogenous surgical site infection but also many endogenous infections. A multicenter surveillance of infection rates at 130 operative departments participating for at least 4 years in the German National Nosocomial Infection Surveillance System was conducted. A significant 25% reduction in the 3rd year was observed compared with patients who underwent surgery within the 1st year of participation. However, surgeons alone cannot achieve such a decrease, and a team approach is required under most circumstances.

Adult↗

Is the prevalence of Stenotrophomonas maltophilia isolation and nosocomial infection increasing in intensive care units?

The study presented here was conducted over a period of 4 years (2001-2004) to investigate changes in the number of S. maltophilia isolates detected per 1,000 patient days and to look at the incidence density of nosocomial infections caused by S. maltophilia. The analysis was based on data provided by 34 German intensive care units participating continuously in the national project "Surveillance of Antimicrobial Use and Resistance in ICUs"; 31 of these ICUs reported nosocomial infections to the German infection surveillance system, KISS, during the study period.

Cross Infection↗

Hand rub consumption and hand hygiene compliance are not indicators of pathogen transmission in intensive care units.

The objective of this study was to investigate whether nosocomial infection (NI) rates, hand hygiene compliance rates and the amount of alcohol-based hand rub used for hand disinfection are useful indicators of pathogen transmission in intensive care units (ICUs), and whether they could be helpful in identifying infection control problems. All isolates of 10 of the most frequent pathogens from patients who were hospitalized in an ICU for >48 h were genotyped to identify transmission episodes in five ICUs. The incidence of transmission was correlated with hand hygiene compliance, hand rub consumption and NI rates. The incidence of transmission episodes varied between 2.8 and 6.8 in the five ICUs. The NI rate was 8.6-22.5 per 1000 patient-days, hand hygiene compliance was 30-47% and hand rub consumption was 57-102 L per 1000 patient-days. There was no correlation between the incidence of transmission episodes and hand rub consumption or hand hygiene compliance. The correlation between transmission rates and NI rates was 0.4 (P = 0.5), and with the exclusion of one ICU, it was 1 (P < 0.01). The incidence of NI is a relatively good indicator for the identification of pathogen transmissions, but hand rub consumption and hand hygiene compliance, at least with the relatively low level of compliance found in this study, are not indicators of pathogen transmission.

Anti-Infective Agents, Local↗

Correlation between the genetic diversity of nosocomial pathogens and their survival time in intensive care units.

Bacteria differ in their ability to survive in the hospital environment outside the human host. Species remaining viable and infectious have a higher chance of being transmitted, giving them a fitness advantage in hospitals. This differential fitness could be expected to alter the genetic population structure of bacterial populations in hospitals, and should be reflected by the relative abundance of several successful clones. The objective of this study was to test for a potential correlation between tenacity, i.e. environmental survival, and clonal abundance determined by the genetic diversity in different bacterial species from prospectively collected isolates of intensive care patients. A literature review was performed to identify mean environmental survival times for the most important pathogens in intensive care units (ICUs): Staphylococcus aureus, enterococci, Acetinobacter baumannii, Pseudomonas aeruginosa, Enterobacter spp., Escherichia coli, Klebsiella pneumoniae and Stenotrophomonas maltophilia. To determine the genetic diversity of the natural population of these species in ICUs, a prospective 18-month study was conducted in five units with median nosocomial infection rates. All clinical isolates were collected, and highly discriminatory DNA fingerprinting techniques were used to identify specific clones. A diversity index for each species was calculated as the number of distinguishable genotypes in the population divided by size. The correlation between survival times and the diversity indices for the individual pathogens was investigated using non-parametric methods. Although 21 studies were identified in the literature, only two were relevant. They showed median survival times between 1.5 days (P. aeruginosa) and 60.0 days (Enterococcus faecium). During the prospective ICU study, 1264 pathogens were investigated and simple diversity indices between 49.1 (Enterococcus faecalis) and 89.8 (E. coli) were found. A correlation between survival times and the diversity indices for the individual pathogens was found (correlation coefficient 0.821, P=0.024). Environmental survival may be an important factor contributing to the ecological fitness of some nosocomial pathogens in ICUs. Infection control measures should consider this finding.

Bacterial Infections↗

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.

Hip Prosthesis↗

Surveillance of nosocomial sepsis and pneumonia in patients with a bone marrow or peripheral blood stem cell transplant: a multicenter project.

BACKGROUND: For surveillance of nosocomial bloodstream infections (BSIs) and pneumonia during neutropenia in adult patients who have undergone bone marrow transplantation (BMT) or peripheral blood stem cell transplantation (PBSCT), a multicenter study--the Hospital Infection Surveillance System for Patients with Hematologic/Oncologic Malignancies (ONKO-KISS)--was initiated in Germany in 2000. METHODS: Nosocomial infections were identified in neutropenic patients by means of Centers for Disease Control and Prevention definitions for laboratory-confirmed BSI and modified criteria for pneumonia. RESULTS: During the first 38-month period of the study (i.e., through December 2003), a total of 1899 patients associated with 28,273 neutropenic days were investigated. Of these, 1173 (62%) had undergone allogeneic and 726 (38%) had undergone autologous BMT or PBSCT. The mean duration of neutropenia was 14.9 days (9.6 and 18.1 days after autologous and allogeneic transplantation, respectively). Overall, 395 BSIs and 168 cases of pneumonia were identified. The pooled mean site-specific incidence density per 1000 neutropenic days was 14.0 for BSI (12.4 and 18.9 for the allogeneic and autologous transplantation groups, respectively) and 5.9 for pneumonia (6.1 and 5.6 in the allogeneic and autologous transplantation groups, respectively). After allogeneic transplantation, 22.4 BSIs per 100 patients and 11.0 cases of pneumonia per 100 patients occurred, whereas 18.2 BSIs per 100 patients and 5.4 cases of pneumonia per 100 patients occurred after autologous transplantation. The majority (57%) of pathogens associated with BSI were coagulase-negative staphylococci. CONCLUSIONS: The ongoing ONKO-KISS project provides unprecedented reference data about the incidence of pneumonia and sepsis among BMT recipients and PBSCT recipients in Germany. These data will be used for further evaluation of the impact of hygiene measures and therapeutic regimens for these patients.

Adolescent↗

[Incidence of transmission of pathogens in intensive care units. Results of the SIR 3 study].

The objective of this study was to determine the incidence of episodes of transmission of nosocomial pathogens and of those pathogens leading to nosocomial infections. Over a period of 18 months all patients from 5 intensive care units (ICUs) who stayed for more than 2 days were included in this study. Surveillance of nosocomial infections was carried out and all isolates of 10 of the most frequent pathogens in ICUs (indicator pathogens) were collected and typed. A total of 28,498 patient days and 431 nosocomial infections were observed (incidence density 15.1 per 1,000 patient days), among them 278 caused by 1 of the selected indicator pathogens. A total of 141 episodes of transmissions were identified, corresponding to an incidence of episodes of transmission of 5.0 per 1,000 patient days and 41 nosocomial infections were transmission-associated, corresponding to 14.5% of all nosocomial infections. The data of this study demonstrate that even in ICUs with average nosocomial infection rates, some nosocomial infections could be avoided.

Anesthesia↗

[Infection control measures in intensive care units. Results of the German Nosocomial Infection Surveillance System (KISS)].

BACKGROUND: Aim of this study was to determine to what extent evidence-based infection control recommendations are applied in German intensive care units (ICUs). METHODS: A questionnaire concerning handling of tubes, central vascular catheters (CVC), urinary tract catheters and methicillin-resistant Staphylococcus aureus (MRSA) positive patients was sent to 230 participants of the German Nosocomial Infection Surveillance System (KISS). RESULTS: Nasal intubation is routinely performed in 9% of ICUs, all recommended measures for CVC insertion were obeyed by 43% of ICUs and one-third of ICUs conduct regular screening of urine in catheterized patients. Urinary tract catheters are replaced at defined time intervals in 37% of ICUs. MRSA positive patients are not isolated in 5% of ICUs. MRSA screening on admission is not performed for high risk patients in 16% of ICUs. CONCLUSIONS: There are still many German ICUs in which evidence-based recommendations are not implemented. Training of staff is necessary to improve quality of patient care.

Catheterization, Central Venous↗

Mortality risk factors with nosocomial Staphylococcus aureus infections in intensive care units: results from the German Nosocomial Infection Surveillance System (KISS).

INTRODUCTION: As the number of nosocomial methicillin-resistant Staphylococcus aureus (MRSA) infections in German intensive care units increases, the problem of MRSA infection as such is becoming ever more serious. The aim of this study was to investigate whether mortality rates from nosocomial MRSA pneumonia and primary bloodstream infections (BSI) differ significantly from those of nosocomial pneumonia and primary BSI caused by methicillin-susceptible S. aureus (MSSA). METHODS: For the analysis data from the ICU component of the German nosocomial infection surveillance system (KISS) were used (January 1997 to June 2002). To identify mortality risk factors a logistic regression analysis with step-wise variable selection was conducted including all cases of nosocomial S. aureus pneumonia and primary BSI. The possible risk factors that were evaluated were age > median, male gender, time in the ICU before infection > median, type of ICU, type and size of hospital, intubation, CVC use, total parenteral nutrition, year of investigation, infection caused by MRSA. RESULTS: Data from 274 ICUs and 505,487 ICU patients were recorded and a total of 6,888 cases of nosocomial pneumonia and 2,357 cases of primary BSI identified, of which 1,851 cases of S. aureus pneumonia and 378 cases of S. aureus primary BSI were considered for analysis. 59 of the 349 patients with MRSA pneumonia (16.9%) and 105 of the 1,502 patients with MSSA pneumonia (7.0%) died. 16 of the 95 patients with primary MRSA BSI (16.8%) and 17 of the 283 patients with primary MSSA BSI died (6.0%). Four factors were significantly associated with mortality from S. aureus pneumonia, one of them being pneumonia caused by MRSA (OR = 2.62; CI95 1.69-4.02). Only MRSA was significantly associated with death from S. aureus primary BSI (OR = 3.84; CI95 1.51-10.2). CONCLUSION: Nosocomial pneumonia and primary BSI from MRSA may be associated with death, but the cause-effect relationship of severity of illness and MRSA remains to be determined due to the limitations of surveillance data.

Cross Infection↗

Occurrence of organotin compounds in house dust in Berlin (Germany).

In a study in the year 2000 on the occurrence of hazardous environmental contaminants house dust samples from 28 Berlin apartments were measured for the presence and concentrations of six organotin compounds, monobutyltin (MBT), dibutyltin (DBT), tributyltin (TBT), monooctyltin (MOT), dioctyltin (DOT) and triphenyltin (TPT). The concentrations of MBT and DBT determined ranged considerably from 0.01 mg kg-1 to 1.5 mg kg-1 (median: 0.05 mg kg-1) and 0.01 to 5.6 mg kg-1 (median: 0.03 mg kg-1), respectively. Maximum levels of TBT and MOT were only 0.08 mg kg-1 and 0.04 mg kg-1. The maximum total value of the organotins was 7.2 mg kg-1 (median: 0.11 mg kg-1). MBT was found in 86% and DBT in 82% of the samples above the limit of quantification, TBT and MOT only in 50% and DOT in 43%. The focus of ecotoxicology is on the risks arising from organotin compounds (especially butyltins) when used as biocides in antifouling paints. TBT acts as an endocrine disrupter in animals, inducing masculinization (imposex) in female gastropods of different species by increasing testosterone levels. The most critical organ site in experimental animals is the cellular immune system, where lymphocyte depletion in the thymus and peripheral lymphoid tissues takes place. Our study does not provide data on the basis of which population exposure could be estimated; house dust containing harmful organotins could, however, under some conditions, become a relevant intake possibility for young children.

Berlin↗

Use of terminal tap water filter systems for prevention of nosocomial legionellosis.

Hospital water supplies often contain Legionella spp. and represent a potential source of nosocomial infection, especially for immunocompromised patients or those in intensive care units. Therefore, pathogen-free water should be provided for such high-risk patients. Surveillance of splash water was performed in high-risk patient care areas at Berlin Charité-University Medicine (506 samples) and Medical School Hannover (767 samples) to investigate the ability to provide water that was free from Legionella spp. by the use of disposable, terminal tap water filter systems with non-impregnated, as well as impregnated, filters with prolonged usage intervals. Twenty (Berlin) and 32 (Hannover) water outlets were provided with disposable filters with a pore size of 0.2 microm. Testing of unfiltered tap water revealed growth of Legionella spp. in 53 of 210 (Berlin) and 30 of 32 (Hannover) samples. Non-impregnated, terminal, disposable water filters at taps used for high-risk patient care led to water free from Legionella spp. in 154 of 155 (99.4%) samples after three to four days and in 137 of 141 (97.2%) samples after six to seven days. When testing a new impregnated filter, 255 of 256 (99.6%) samples remained free from Legionella spp. after continuous use for seven days, as recommended by the manufacturers, and also after 10 days. Samples that were positive for Legionella spp. contained 1-4 cfu/mL. We believe that an impregnated filter system is suitable for the prevention of nosocomial Legionellosis in high-risk patient care areas.

Berlin↗

[Mortality in German intensive care units: dying from or with a nosocomial infection?].

OBJECTIVE: To describe mortality from intensive care unit acquired infections in German ICUs. METHODS: The hospital infection surveillance system (KISS = Krankenhaus-Infektions-Surveillance-System) started in Germany in January 1997 as a nationwide surveillance project for the voluntary registration of nosocomial infections. For ICUs reporting focuses on pneumonia and primary bloodstream infections. The data collected for each patient who acquires a nosocomial infection include outcome information. Data of a recent French study and the Statistical Yearbook were used to estimate the annual number of ICU acquired infections contributing to death in Germany. RESULTS: Data from 897 774 ICU patients were considered for the analysis (January 1997-June 2004). ICU mortality of patients with nosocomial pneumonia was 8.8 %, of patients with primary bloodstream infection was 10,9 %. Of the ICU patients with nosocomial pneumonia and primary bloodstream infections about 3554 die annually, in about 1131 cases the nosocomial infection was the cause of death. It may be estimated that the ICU acquired cases of pneumonia and primary bloodstream infection contributed to the death of about 2400 patients annually in Germany. CONCLUSION: Because of the substantial mortality of patients with ICU acquired infections preventive measures have a high priority. Further studies leading to improved infection control measures are very wellcome.

Bacteremia↗