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H Rüden

Publications and source records attributed to H Rüden.

At least 19 recordsLinked to original sources

[Reliable and unreliable health measures in surgery].

Despite high standards in theatre design, surgical skills and antibiotic prophylaxis, surgical site infections are still a major complication in modern surgery. After urinary tract infections and lower respiratory tract infections they account for 15.8% of all nosocomial infections in Germany [31]. Causes are multiple and only partially exogenous. The single most important (exogenous) risk factor is the technical skill of the surgeon. Not all surgical site infections are therefore preventable by infection control measures alone. Useful and useless infection control measures will be evaluated critically in the following review according to data in the literature.

Air Microbiology↗

[Surveillance of postoperative wound infections: reference data of the Hospital Infection Surveillance System (KISS)].

BACKGROUND: Surgical site infections (SSI), the third-most-frequent nosocomial infection, are a problem in all fields of surgery. Assessing the level of one's own infection rates is often difficult, since there have been no suitable comparative data available in Germany in the past due to the lack of a uniform method of determining these rates. METHODS: Based on an American model, the Hospital Infection Surveillance System (KISS) has been carrying out a standard recording of SSI since 1997 in meanwhile 132 surgical departments of 89 hospitals. Specially trained hygiene personnel record SSI according to CDC definitions in selected indicator operations. RESULTS: Since January 1997, 1,549 SSI have been recorded in 71,038 operations using 13 different surgical techniques. The risk-ratified SSI rates for each of these surgical techniques are provided and can serve as orientational data for other departments. CONCLUSION: The KISS reference data can help in assessing one's own SSI rates. A prerequisite is surveillance according to the KISS protocol.

Confidence Intervals↗

Occurrence of methicillin-resistant Staphylococcus aureus infections in German intensive care units.

BACKGROUND: This study aims to describe the occurrence of nosocomial methicillin-resistant Staphylococcus aureus (MRSA) infections and the relation between endemic and epidemic nosocomial MRSA infections in intensive care units (ICUs) in Germany. METHODS: The ICU component within the German national nosocomial infections surveillance system (KISS) was established in January 1997. The number of participating ICUs increased from 25 in 1997 to 178 (June 2000). In every case of nosocomial infection (NI), the pathogens identified were referred to the surveillance system. To identify clusters and outbreaks and distinguish them from mere single events, the following simple definitions were applied: a "cluster" was two nosocomial MRSA infections within 3 months; an "outbreak" was three or more nosocomial MRSA infections within 3 months; all other MRSA infections were classed as "single events." RESULTS: A total of 10,261 NIs were identified during the observation period in the 139 ICUs which had been participating for at least 6 months. Among the 1,535 nosocomial S. aureus infections, 219 MRSA infections were identified (14.3%). Only 51 (36.7%) of the 139 KISS ICUs identified nosocomial MRSA infections. In 12 ICUs (8.6%) however, more than 50% of all nosocomial S. aureus infections were caused by MRSA. The mean incidence density was 0.31 nosocomial MRSA infections/1,000 patient days (range 0-3.6). Outbreaks were registered in 13 ICUs, clusters in 12 further ICUs and only single events in the remaining 26. 64.0% of all MRSA infections were registered during outbreaks and 12.8% in cluster situations. Thus, only 23.2% of MRSA infections were single events. CONCLUSION: These definitions of clusters and outbreaks can only provide an estimate of the real number of cases. However, through the targeted identification of ICUs with endemic and epidemic MRSA problems and subsequent strict measures to prevent the spread of MRSA within these ICUs, it may be possible to retain, or even reduce, the present level of MRSA infections in Germany.

Cross Infection↗

The practice of perioperative antibiotic prophylaxis in eight German hospitals.

BACKGROUND: Although there is consensus in the international literature on the benefits of using perioperative antibiotic prophylaxis (PAP), there is still considerable scope for improving its use in many hospitals. MATERIALS AND METHODS: In this study, data on the practice of PAP were recorded in eight German hospitals within the framework of a prospective controlled interventional study for the surveillance and prevention of nosocomial infections. RESULTS: A total of 627 surgical procedures (appendectomies, other colorectal procedures, total prosthetic hip replacement) were assessed; 397 with PAP and 224 without PAP; six procedures could not be evaluated. Of the 397 PAP recorded, only 180 (45.3%) were performed correctly in accordance with international standards as a preoperative single dose (19/59 PAP in appendectomies, 72/188 PAP in other colorectal procedures, 89/150 PAP in total prosthetic hip replacement). CONCLUSION: There is still great uncertainty regarding the point in time at which PAP should be administered and its duration. Additional efforts are necessary to improve PAP in accordance with published evidence-based guidelines.

Anti-Bacterial Agents↗

[Compliance with hand hygiene in intensive care units].

INTRODUCTION: Nosocomial infections are an important problem in modern hospitals. The prevalence in German intensive care units is 15.3%. Hand washing or hand disinfection is believed to be the most important means of preventing nosocomial infections. We wished to answer the following questions: 1. How good is the compliance of hand hygiene on intensive care units? 2. Is compliance associated with the patient/nurse-ratio? METHOD: In a study of 8 intensive care units the compliance of hand hygiene was observed on two occasions, once in May 1996 and again in November 1997. The prime necessity for hand disinfection occurred when handling ventilation devices, intravascular catheters, urinary catheters and dressings. In addition the patient/nurse-ratio was calculated. RESULTS: A total of 1,879 infection-relevant handlings were observed. The compliance of hand hygiene ranged from 25.7 to 83.2% (mean 55.2%). The most commonly observed handlings were the manipulation of venous catheters (52.7%), the highest compliance was observed with the manipulation of ventilation equipment (91.8%). With a better patient nurse ratio the compliance did not improve but remained the same or was even reduced. DISCUSSION: The compliance of hand disinfection is similar to other study results, but on some intensive care units there was considerable room for improvement. In this study the compliance of hand hygiene is more of a constant factor in individual intensive care units than associated with the patient/nurse-ratio.

Attitude of Health Personnel↗

Surveillance of nosocomial infections in a neurology intensive care unit.

To identify overall and site-specific nosocomial infection (NI) rates in patients receiving neurological intensive care therapy, a prospective study was started in 1997 in the ten-bed neurological intensive-care unit (NICU) of the University Hospital of Freiburg, Germany. Case records and microbiology reports were reviewed twice a week, and ward staff were consulted. NI were defined according to the Center for Disease Control and Prevention (CDC) criteria and were categorised by specific infection site. Within 30 months, 505 patients with a total of 4,873 patient days were studied (mean length of stay: 9.6 days). 122 NI were identified in 96 patients (74 patients with one, 18 with two and 4 with three infections. An incidence of 24.2/100 patients and incidence density of 25.0/1,000 patient days of NI in the neurological ICU were documented. Site-specific incidence rates and incidence densities were: 1.4 bloodstream infections per 100 patients (1.9 central line-associated BSIs per 1,000 central line-days), 11.7 pneumonias per 100 patients (20.4 ventilator-associated pneumonias per 1,000 ventilator-days), 8.7 urinary tract infections per 100 patients (10.0 urinary catheter-associated urinary track infections (UTIs) per 1,000 urinary catheter-days). Additionally, 0.4 cases of meningitis, 0.8 ventriculitis, and 1.2 other infections (catheter-related local infection, diarrhea) were documented per 1,000 patient days. 15% of nosocomial pathogens were A. baumannii (due to a outbreak of an nosocomial pneumonia with A. baumannii), 13% S. aureus, 10% E. coli, 7% CNS,7% Bacteroides spp., 7% Enterobacter spp., 6,5% Klebsiella spp.,5.9% enterococci, 5.9% streptococci, and 4.7% Pseudomonas spp. In eight cases of NI no pathogen could be isolated. In future, data on NI in NICUs should be assessed in greater detail, both to improve the quality of care and serve as a basis for identification and implementation of the most effective measures by which to prevent these infections in patients receiving intensive neurological care.

Adolescent↗

The organization of infection control in Germany.

The authors outline the organization of infection control in Germany, focusing on official regulations, the training of infection control staff, and functions of the infection control committee and the availability of guidelines.

Cross Infection↗

[Prevention of postoperative wound infections. Evidence-based recommendations].

Among all hospitalized patients, surgical site infections (SSI) are the third most frequently hospital-acquired-infection. SSIs remain a substantial cause of morbidity and mortality among surgical patients. This may be partially explained by the emergence of antimicrobial-resistant pathogens and the increased numbers of patients who are elderly and/or have a wide variety of chronic, debilitating, or immunocompromising underlying diseases. This is why it is essential to implement SSI prevention measures. In April 1999 the Centers for Disease Control and Prevention (CDC) presented the "Guideline for Prevention of Surgical Site Infection". The recommendations represent the consensus of the Hospital Infection Control Practices Advisory Committee (HICPAC) regarding strategies for the prevention of SSIs. Whenever possible, the recommendations are based on data from well-designed scientific studies. This guideline is a major step forward and is also essential to optimize the management of surgical patients in Germany.

Age Factors↗

[Reduction of nosocomial infections by a public health quality management concept in surgical patients. 1: Significant reduction of a high initial rate].

A successful introduction of surveillance of NI and quality circles for prevention of infection was achieved in hospital A. The major requirements therefore are according to our experiences determination of the topics of the quality circles by the participants themselves, interest and engagement for the work of the quality circles and the realization of ideas, support by the hospitals' management, acceptance of this work by the wards, continuous evaluation of the work of the quality circle. Often the most important problem was not identification of weaknesses and creating of possible solutions, but putting the ideas into practice on the wards. This was the case for problems in the field of care as well as in the responsibility of physicians. Altogether a significant 42% reduction of nosocomial infections was achieved.

Cross Infection↗

[Reduction of nosocomial infections by public health quality management in surgical patients. 2: No reduction in low initial infection rate].

In the framework of a prospective controlled study in surgical and intensive care units of four study and four control hospitals it was tried to set up an infection control quality management concept for reduction of nosocomial infections in hospital D. With an incidence density of 5.4 nosocomial infections per 1,000 patient days the most favorable situation among the four study hospitals was found initially in this hospital. However, after a small decrease of infection rate during the first study year, no benefit of intervention was achieved in this hospital at the end of the study (6.4 nosocomial infections per 1,000 patient days). Possible explanations may be a very small potential for reduction at the beginning, a change of patient mix due to a new head of the department and the phenomenon of the "regression to the mean". Distinct improvements of the situation were achieved on the level of process quality. Meanwhile surveillance of nosocomial infections became an integral part of quality management in this hospital. The quality circle method was not well accepted for the longterm. But the concept of link nurses was introduced successfully.

Cross Infection↗

Capability of air filters to retain airborne bacteria and molds in heating, ventilating and air-conditioning (HVAC) systems.

The capability of air filters (filterclass: F6, F7) to retain airborne outdoor microorganisms was examined in field experiments in two heating, ventilating and air conditioning (HVAC) systems. At the beginning of the 15-month investigation period, the first filter stages of both HVAC systems were equipped with new unused air filters. The number of airborne bacteria and molds before and behind the filters were determined simultaneously in 14 days-intervals using 6-stage Andersen cascade impactors. Under relatively dry (< 80% R. H.) and warm (> 12 degrees C) outdoor air conditions air filters led to a marked reduction of airborne microorganism concentrations (bacteria by approximately 70% and molds by > 80%). However, during long periods of high relative humidity (> 80% R. H.) a proliferation of bacteria on air filters with subsequent release into the filtered air occurred. These microorganisms were mainly smaller than 1.1 microns therefore being part of the respirable fraction. The results showed furthermore that one possibility to avoid microbial proliferation is to limit the relative humidity in the area of the air filters to 80% R. H. (mean of 3 days), e.g. by using preheaters in front of air filters in HVAC-systems.

Air Conditioning↗

Converting incidence and prevalence data of nosocomial infections: results from eight hospitals.

OBJECTIVE: To investigate the use of the formula of Rhame and Sudderth for the interconversion of prevalence and incidence data on the frequency of nosocomial infections. DESIGN: Comparison of observed and calculated incidence data and prevalence data. SETTING: One 8-week incidence investigation in the surgical and intensive care units of eight medium-sized hospitals; three separate point-prevalence studies in the same units. RESULTS: The overall prevalence observed after the three prevalence studies in 2,169 patients was 6.8% (95% confidence interval [CI95], 5.7-8.0). In 2,882 discharged patients observed during the incidence study, the mean hospitalization was 9.8 days; patients with one or more nosocomial infection had a mean hospitalization time of 22.3 days and a mean interval of 8.2 days from admission to the first day of infection. Based on these data, the overall calculated incidence was 4.7%, whereas the observed incidence was 4.3% (CI95, 3.6-5.2). Vice versa, an overall prevalence of 6.2% was found when calculated from the observed incidence data. The incidence data calculated from prevalence data also were within the confidence interval of the incidences observed for urinary tract infections and surgical-site infections. (However, it was not possible to convert the data for two of the eight hospitals.) CONCLUSION: The approximate mathematical relationship between the prevalence and incidence data of nosocomial infection is confirmed by this study. However, although it is theoretically possible, we would not recommend the conversion of prevalence into incidence data or vice versa.

Cross Infection↗

Surveillance of nosocomial infections in ICUs: is postdischarge surveillance indispensable?

OBJECTIVE: To determine how many infections are missed if the postdischarge surveillance (PDS) follow-up of intensive care unit (ICU) patients that is required by the National Nosocomial Infection Surveillance System method is not done. DESIGN: ICU patients were followed up and surveillance results with PDS (gold standard) and without PDS were compared. SETTING: Surgical or interdisciplinary ICUs in eight German acute-care hospitals. PATIENTS: All 1,857 patients within a 6-month period in the participating ICUs (a total of 9,129 ICU-patient-days). RESULTS: Without PDS, 45 urinary tract infections (UTIs) were diagnosed, compared with 53 with PDS; thus, 15% of the UTIs were missed if no postdischarge follow-up was performed. Three nosocomial pneumonias (4%) and one bloodstream infection (8%) also were missed if surveillance was carried out without PDS. A total of 198 nosocomial infections (NIs) were recorded with PDS, compared to 175 NIs without PDS. Approximately 12% of all ICU-associated NIs were missed if no follow-up was done. CONCLUSIONS: Since it is very time-consuming to follow patients after their transfer from the ICU, we do not perform a postdischarge follow-up of patients in the course of routine surveillance.

Cross Infection↗

[Human granulocytic ehrlichiosis. New tick bite disease lies in wait also in German forests].

HGE is an uncommon zoonosis, transmitted to humans by ticks (Ixodes ricinus). Heavily exposed persons, such as foresters and forestry workers, are most at risk of infection. HGE usually runs an asymptomatic and self-limiting course. Symptoms include acute pyrexial illness, frequently accompanied by muscle pain, headache, nausea and vomiting. Treatment is with doxycycline/tetracycline or rifampicin. In a study in Hesse of 128 heavily exposed subjects, 19.5% had serum antibodies (IFA test) against HGE versus 4.4% in a control group. This difference is statistically significant. The prevalence of both symptoms and the seropositivity differ significantly between locations. HGE should be considered in the differential diagnosis of fever of unknown origin following tick bite exposure, at least in the North Hesse region.

Animals↗