Sonja Hansen
Charité
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Featured researches published by Sonja Hansen.
Transplantation | 2002
Nada Rayes; Daniel Seehofer; Sonja Hansen; Kathrin Boucsein; A.R Müller; Stefan Serke; Stig Bengmark; Peter Neuhaus
Background. Early enteral nutrition with solutions containing prebiotics (fiber) and probiotics (Lactobacillus) is suggested to reduce bacterial translocation and minimize the incidence of infections after liver transplantation. Methods. In a prospective, randomized placebo-controlled trial consisting of 95 patients, we compared the incidence of postoperative infections and other complications after liver transplantation among three different groups, all supplied with early enteral nutrition: (a) standard formula plus selective bowel decontamination (SBD), (b) fiber-containing formula plus living Lactobacillus plantarum 299, and (c) fiber-containing formula plus heat-killed L plantarum 299. Results. The groups were comparable regarding preoperative American Society of Anesthesiologists classification, Child-Pugh classification of cirrhosis, operative data, and degree of immunosuppression. The patients who received living lactobacilli plus fiber developed significantly fewer bacterial infections (13%) than the patients with SBD (48%). The incidence of infections was 34% in the group with inactivated lactobacilli and fiber. Cholangitis and pneumonia were the leading infections and enterococci the most commonly isolated bacteria. In the living Lactobacillus group, the mean duration of antibiotic therapy, the mean total hospital stay, and the stay on the intensive care unit were also shorter than in the groups with inactivated lactobacilli and fiber as well as with SBD. However, these differences did not reach statistical significance. Conclusions. Early enteral nutrition with fiber-containing solutions and living L plantarum 299 was well tolerated. It decreases markedly the rate of postoperative infections both in comparison with inactivated L plantarum 299 and significantly with SBD and a standard enteral nutrition formula. As it is a cheap and feasible alternative to SBD, further studies should evaluate whether this ecoimmunonutrition should be already started while patients are on the waiting list for transplantation.
Nutrition | 2002
Nada Rayes; Sonja Hansen; Daniel Seehofer; A.R Müller; Stefan Serke; Stig Bengmark; Peter Neuhaus
OBJECTIVE Early enteral nutrition with fiber-containing solutions plus Lactobacillus may reduce bacterial translocation and minimize the incidence of infections after surgery. METHODS In a prospective, randomized trial in three groups (n = 30/group) of patients after major abdominal surgery, we compared our previous regimen with parenteral nutrition or fiber-free enteral nutrition (group A) with enteral fiber-containing nutrition with living Lactobacillus (group B) and heat-killed Lactobacillus (group C). The main endpoint was the development of bacterial infection. Other analyzed parameters were the durations of antibiotic therapy and hospital stay, non-infectious complications, side effects of the nutrition, and onset of bowel movement. Routine parameters, nutritional parameters, and cellular immune status in the blood were measured preoperatively and on 1, 5, and 10 d postoperatively. RESULTS The incidence of infections was significantly lower (P = 0.01) in groups B and C with enteral nutrition containing fibers (10% each) than in group A (30%). Patients in group B received antibiotics for a significantly shorter time (P = 0.04) than did the patients in groups A and C. The length of hospital stay and the incidence of non-infectious complications did not differ significantly. Fibers and lactobacilli were well tolerated. There were no general benefits of living Lactobacillus as opposed to heat-killed Lactobacillus in the entire study population, but benefits were observed in the patients with gastric and pancreas resections, although no statistical analysis was done due to their small numbers. CONCLUSIONS Early enteral nutrition with fiber-containing solutions reduced the rate of postoperative infections in comparison with parenteral nutrition and fiber-free enteral formula. Addition of living Lactobacillus seemed to increase the benefits in patients with gastric and pancreatic resections.
Journal of Hospital Infection | 2007
Sonja Hansen; Sabine Stamm-Balderjahn; Zuschneid I; Michael Behnke; H. Rüden; R.-P. Vonberg; P. Gastmeier
Summary A total closure of an affected medical department is one of the most expensive infection control measures during investigation of a nosocomial outbreak. However, until now there has been no systematic analysis of typical characteristics of outbreaks, for which closure was considered necessary. This article presents data on features of such nosocomial epidemics published during the past 40 years in the medical literature. A search of the Outbreak Database (1561 nosocomial outbreaks in file) revealed a total of 194 outbreaks that ended up with some kind of closure of the unit (median closure time: 14 days). Closure rates (CRs) were calculated and stratified for medical departments, for causative pathogens, for outbreak sources, and for the assumed mode of transmission. Data were then compared to the overall average CR of 12.4% in the entire database. Wards in geriatric patient care were closed significantly more frequently (CR: 30.3%; P <0.001) whereas paediatric wards showed a significantly lower CR (6.1%; P =0.03). Pathogen species with the highest CR were norovirus (44.1%; P <0.001) and influenza/parainfluenza virus (38.5%; P <0.001). If patients were the source of the outbreak, the CR was significantly increased (16.7%; P =0.03). Infections of the central nervous system were most often associated with closure of the ward (24.2%; P =001). A systematic evaluation of nosocomial outbreaks can be a valuable tool for education of staff in the absence of an outbreak, but may be even more helpful for potentially cost-intensive decisions in the acute outbreak setting on the ward.
Infection Control and Hospital Epidemiology | 2006
Ralf-Peter Vonberg; Sabine Stamm-Balderjahn; Sonja Hansen; Irina Zuschneid; Henning Rüden; Michael Behnke; Petra Gastmeier
A systematic search was performed to identify outbreaks of methicillin-resistant Staphylococcus aureus infection and colonization caused by healthcare workers (HCWs). Of 191 outbreaks identified, 11 had strong epidemiological evidence that HCWs were the source. In 3 of these outbreaks, asymptomatic carriers were the cause. The frequent practice of screening asymptomatic HCWs should be reconsidered.
Infection Control and Hospital Epidemiology | 2005
Petra Gastmeier; Sabine Stamm-Balderjahn; Sonja Hansen; Frauke Nitzschke-Tiemann; Zuschneid I; Katrin Groneberg; H. Rüden
OBJECTIVE To describe the epidemiology of nosocomial outbreaks published in the scientific literature. DESIGN Descriptive information was obtained from a sample of 1,022 published nosocomial outbreaks from 1966 to 2002. METHODS Published nosocomial outbreaks of the most important nosocomial pathogens were included in the database. A structured questionnaire was devised to extract information in a systematic manner on nosocomial outbreaks published in the literature. The following items were used: the reference, type of study (case reports or studies applying epidemiologic or fingerprinting methods), type of microorganism, setting, patients and personnel involved, type of infection, source of infection, mode of transmission, risk factors identified, and preventive measures applied. RESULTS Bloodstream infection was the most frequently identified type of infection (37.0%), followed by gastrointestinal infection (28.5%) and pneumonia (22.9%). In 37% of the outbreaks, the authors were not able to identify the sources. The most frequent sources were patients (25.7%), followed by medical equipment or devices (11.9%), the environment (11.6%), and the staff (10.9%). The mode of transmission remained unclear in 28.3% of the outbreaks. Transmission was by contact in 45.3%, by invasive technique in 16.1%, and through the air in 15.0%. The percentage of outbreaks investigated by case-control studies or cohort studies over the years was small (21% and 9%, respectively, for the whole time period). CONCLUSION Outbreak reports in the literature are a valuable resource and should be used for educational purposes as well as for preparing outbreak investigations.
Infection Control and Hospital Epidemiology | 2004
C. Brandt; Sonja Hansen; Dorit Sohr; F. Daschner; H. Rüden; Petra Gastmeier
OBJECTIVE To investigate whether stratification of the risk of developing a surgical-site infection (SSI) is improved when a logistic regression model is used to weight the risk factors for each procedure category individually instead of the modified NNIS System risk index. DESIGN AND SETTING The German Nosocomial Infection Surveillance System, based on NNIS System methodology, has 273 acute care surgical departments participating voluntarily. Data on 9 procedure categories were included (214,271 operations). METHODS For each of the procedure categories, the significant risk factors from the available data (NNIS System risk index variables of ASA score, wound class, duration of operation, and endoscope use, as well as gender and age) were identified by multiple logistic regression analyses with stepwise variable selection. The area under the receiver operating characteristic (ROC) curve resulting from these analyses was used to evaluate the predictive power of logistic regression models. RESULTS For most procedures, at least two of the three variables contributing to the NNIS System risk index were shown to be independent risk factors (appendectomy, knee arthroscopy, cholecystectomy, colon surgery, herniorrhaphy, hip prosthesis, knee prosthesis, and vascular surgery). The predictive power of logistic regression models (including age and gender, when appropriate) was low (between 0.55 and 0.71) and for most procedures only slightly better than that of the NNIS System risk index. CONCLUSION Without the inclusion of additional procedure-specific variables, logistic regression models do not improve the comparison of SSI rates from various hospitals.
Deutsches Arzteblatt International | 2013
Michael Behnke; Sonja Hansen; Rasmus Leistner; Luis Alberto Peña Diaz; Alexander Gropmann; Dorit Sohr; Petra Gastmeier; Brar Piening
BACKGROUND In 2011, seventeen years after the first national study on the prevalence of nosocomial infections and antibiotic use in German hospitals, a second national prevalence study was carried out according to the specifications of the European Centre for Disease Prevention and Control (ECDC). METHODS The ECDC protocol, containing uniform surveillance definitions and ascertainment methods, was implemented. The only infections counted were those that were active or under treatment with antibiotics on the day of the study. In addition to the representative sample required by the ECDC, which consisted of 46 hospitals, further hospitals participated on a voluntary basis. RESULTS Data on 41 539 patients in 132 hospitals were analyzed. The prevalence of infections that had arisen during the current hospital stay was 3.8% in the overall group and 3.4% in the representative sample of 9626 patients in 46 hospitals. The prevalence of all nosocomial infections, including those acquired before the current hospital stay and still present upon admission, was 5.1% in both the overall group and the representative sample. The prevalence of antibiotic use on the day of the study was 25.5% and 23.3% in the two groups, respectively. CONCLUSION The prevalence of nosocomial infection has not changed since 1994, but the prevalence of antibiotic use has increased. In interpreting these findings, one should bear in mind that confounders may have influenced them in different directions: The mean length of hospital stay is now shorter than in 1994, but the mean age of hospitalized patients is higher.
Antimicrobial Resistance and Infection Control | 2012
Sonja Hansen; D. Sohr; Christine Geffers; Pascal Astagneau; Alexander Blacky; Walter Koller; Ingrid Morales; Maria Luisa Moro; Mercedes Palomar; Emese Szilágyi; Carl Suetens; Petra Gastmeier
BackgroundSurveillance of healthcare-associated infections (HAI) is a valuable measure to decrease infection rates. Across Europe, inter-country comparisons of HAI rates seem limited because some countries use US definitions from the US Centers for Disease Control and Prevention (CDC/NHSN) while other countries use European definitions from the Hospitals in Europe Link for Infection Control through Surveillance (HELICS/IPSE) project. In this study, we analyzed the concordance between US and European definitions of HAI.MethodsAn international working group of experts from seven European countries was set up to identify differences between US and European definitions and then conduct surveillance using both sets of definitions during a three-month period (March 1st -May 31st, 2010). Concordance between case definitions was estimated with Cohen’s kappa statistic (κ).ResultsDifferences in HAI definitions were found for bloodstream infection (BSI), pneumonia (PN), urinary tract infection (UTI) and the two key terms “intensive care unit (ICU)-acquired infection” and “mechanical ventilation”. Concordance was analyzed for these definitions and key terms with the exception of UTI. Surveillance was performed in 47 ICUs and 6,506 patients were assessed. One hundred and eighty PN and 123 BSI cases were identified. When all PN cases were considered, concordance for PN was κ = 0.99 [CI 95%: 0.98-1.00]. When PN cases were divided into subgroups, concordance was κ = 0.90 (CI 95%: 0.86-0.94) for clinically defined PN and κ = 0.72 (CI 95%: 0.63-0.82) for microbiologically defined PN. Concordance for BSI was κ = 0.73 [CI 95%: 0.66-0.80]. However, BSI cases secondary to another infection site (42% of all BSI cases) are excluded when using US definitions and concordance for BSI was κ = 1.00 when only primary BSI cases, i.e. Europe-defined BSI with ”catheter” or “unknown” origin and US-defined laboratory-confirmed BSI (LCBI), were considered.ConclusionsOur study showed an excellent concordance between US and European definitions of PN and primary BSI. PN and primary BSI rates of countries using either US or European definitions can be compared if the points highlighted in this study are taken into account.
Journal of Hospital Infection | 2013
M Martin; Walter Zingg; Sonja Hansen; Petra Gastmeier; Albert W. Wu; Didier Pittet; Markus Dettenkofer
BACKGROUND There is increasing interest in public reporting of healthcare-associated infection (HAI) data in Europe, mostly for patient safety reasons. But it is uncertain whether patients and other stakeholders benefit from them. AIM To obtain the views of European infection control opinion leaders and provide information about public reporting of HAI in Europe. METHODS European Centre for Disease Prevention and Control HAI surveillance National Contact Points and other opinion leaders in infection control from 34 European countries were invited to complete questionnaires about HAI reporting in their countries and to provide their personal views about public reporting. The issue was discussed during two discussion rounds in 2010 and 2012. FINDINGS Response rates were 100% and 93.9% for the two surveys. Current practices on publishing HAI data vary widely across Europe. Many experts support the idea of publishing HAI data. All representatives from the seven countries with established public reporting were in favour of such practice. After the first discussion round, 12 experts changed their opinion. Finally, the majority of the experts acknowledged the positive influence on hospitals by increasing competition on the basis of quality, but they are hesitant about publishing infection rates as these can be misinterpreted by patients and need standardization and validation. CONCLUSION Opinion leaders in infection control in Europe acknowledged the positive influence of public reporting on hospital performance and resulting efforts to reduce infections. They were in favour of reporting of individual hospital data if (i) process indicators rather than outcome data are reported, and (ii) delivery of surveillance is monitored by external audits.
Journal of Hospital Infection | 2014
Sonja Hansen; Frank Schwab; Sandra Schneider; D. Sohr; Petra Gastmeier; Christine Geffers
BACKGROUND Prevention measures reduce central-line-associated bloodstream infections (CLABSIs) but are not always implemented. AIM To investigate the effect of a central educational programme in German intensive care units (ICUs) on CLABSI rates. METHODS Thirty-two German ICUs with CLABSI rates greater than or equal to the national average were compared with two control groups containing 277 and 67 ICUs. Processes and CLABSI rates were surveyed before, during and two years after the implementation of a year-long intervention programme. Segmented regression analysis of interrupted time series using generalized linear models was performed to estimate the association between the number of CLABSIs per month and time, intervention and other confounders, with the clustering effect within an ICU taken into account. FINDINGS In total, 508 cases of CLABSI were observed over 266,471 central line (CL)-days. At baseline, the pooled mean CLABSI rate was 2.29 per 1000 CL-days, and this decreased significantly to 1.64 per 1000 CL-days in the follow-up period. Compared with baseline, the relative risk for CLABSI was 0.88 [95% confidence interval (CI) 0.70-1.11] for the intervention period and 0.72 (95% CI 0.58-0.88) for the follow-up period. No changes were observed in either control group. Following successful implementation of the programme, ICUs showed a significant decrease in CLABSI rates. Although rates were already decreasing prior to implementation of the intervention, the invitation to participate in the study, and increased general awareness of CLABSI prevention through use of the comprehensive multi-modal training materials may have had a beneficial effect on practice.