S W Lemmen

University Hospital RWTH Aachen, Aachen, North Rhine-Westphalia, Germany

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Publications (67)113.42 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: To assess the influence of signal colors on hand disinfectant dispenser activities, health care workers (HCWs) at a medical intensive care unit were analyzed for a total of 20 weeks with 8 weeks before and 12 weeks after exchange to signal color. No significant increase in hand rubs (HRs) per patient day (PD) was observed (about 40 HRs/PD); however, HCW-adjusted compliance showed a 6% increase with signal colored devices. Therefore, colored devices may help to improve hand hygiene compliance.
    American Journal of Infection Control. 08/2014; 42(8):926–928.
  • S Lemmen, S Scheithauer
    DMW - Deutsche Medizinische Wochenschrift 04/2014; 139(14):693-5. · 0.65 Impact Factor
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    ABSTRACT: The purpose of this report was to assess the safety and application of chlorhexidine (CHG)-containing dressings-shown to reduce central line infection rates markedly-for external ventricular drainages (EVDs) and lumbar drainages (LDs). Cerebrospinal fluid samples of patients receiving standard dressings and CHG-containing dressing (ten each) were analyzed by high-performance liquid chromatography for the presence of CHG. The application was evaluated. CHG was not detectable in all samples. The dressings' application for EVDs and LDs worked without problems. Thus, the use of CHG-containing dressings for EVDs and LDs seems to be safe. Further studies addressing their infection reduction potential are warranted.
    Infection 02/2014; · 2.44 Impact Factor
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    ABSTRACT: The reduction of central venous line (CVL)-associated bloodstream infections (CLABSIs) is generally advocated. However, despite implementing infection prevention recommendations, CLABSI rates remain high at some institutions. Therefore, a chlorhexidine-containing dressing should be assessed for its potential for infection reduction, adverse events (AEs) and practicability. The number of CVLs, CVL days, CLABSIs and CLABSI rates with regard to the kind of dressing (standard vs. chlorhexidine-containing) were documented from November 2010 to may 2012 (1,298 patients with 12,220 CVL days) at two intensive care units (ICUs) and compared to historical controls. The practicability and safety of the chlorhexidine-containing dressing and reasons for not using this dressing were assessed. Forty CLABSIs occurred in 34 patients, resulting in a significantly lower overall CLABSI rate in patients with the chlorhexidine-containing dressing [1.51/1,000 CVL days; confidence interval (CI): 0.75-2.70] compared to patients with the standard dressing (5.87/1,000 CVL days; CI: 3.93-8.43; p < 0.0001). The CLABSI rate in historical controls receiving the standard dressing was 6.2/1,000 CVL days. The main reason for not using chlorhexidine-containing dressing was bleeding at the insertion site. AEs occurred in five patients and represented self-healing skin macerations (3 cases) and superficial skin necrosis (2 cases). In case of high CLABSI rates despite the implementation of standard recommendations, our findings suggest that a chlorhexidine-containing dressing safely decreases CLABSI rates.
    Infection 08/2013; · 2.44 Impact Factor
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    ABSTRACT: The emergency department (ED) represents an environment with a high density of invasive, and thus, infection-prone procedures. The two primary goals of this study were (1) to define the number of hand-rubs needed for an individual patient care at the ED and (2) to optimize hand hygiene (HH) compliance without increasing workload. Prospective tri-phase (6-week observation phases interrupted by two 6-week interventions) before after study to determine opportunities for and compliance with HH (WHO definition). Standard operating procedures (SOPs) were optimized for invasive procedures during two predefined intervention periods (phases I and II) to improve workflow practices and thus compliance with HH. 378 patient cases were evaluated with 5674 opportunities for hand rubs (HR) and 1664 HR performed. Compliance significantly increased from 21% (545/2603) to 29% (467/1607), and finally 45% (652/1464; all p<0.001) in phases 1, 2, and 3, respectively. The number of HR needed for one patient care significantly decreased from 22 to 13 for the non-surgical and from 13 to 7 for the surgical patients (both p<0.001) due to improved workflow practices after implementing SOPs. In parallel, the number of HR performed increased from 3 to 5 for non-surgical (p<0.001) and from 2 to 3 for surgical patients (p=0.317). Avoidable opportunities as well as glove usage instead of HR significantly decreased by 70% and 73%, respectively. Our study provides the first detailed data on HH in an ED setting. Importantly, HH compliance improved significantly without increasing workload.
    BMC Infectious Diseases 08/2013; 13(1):367. · 3.03 Impact Factor
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    ABSTRACT: Here we investigated a cluster of eight newly Methicillin-resistant Staphylococcus aureus (MRSA)-colonized neonates at an ICU, and present data on molecular strain characterization as well as the source identification process in which we analyze the impact of MRSA-colonized HCWs. Molecular strain characterization revealed a unique pattern which was identified as spa-type t 127 - an extremely rare strain type in Germany. Environmental sampling and screening of parents of colonized neonates proved negative. However, staff screening identified one healthcare worker (HCW; 1/134) belonging to a group of recently employed Romanian HCWs who was colonized with the spa 127 strain. Subsequent screening also detected MRSA in 9/51 Romanian HCWs (18%) and 7/9 (14% of all) isolates showed the same molecular pattern as the index case (spa/PFGE type). All carriers were successfully decolonized, after which no new patient cases occurred. As a result, we have now implemented a universal screening programme of all new employees as part of our infection control management strategy. MRSA-colonized HCWs can act as a source for in hospital transmission. Since HCWs from high endemic countries are particular prone to being colonized, they may pose a risk to patients.
    International journal of hygiene and environmental health 07/2013; · 2.64 Impact Factor
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    Antimicrobial Resistance and Infection Control. 06/2013; 2(1).
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    ABSTRACT: BACKGROUND: The anesthesia working area represents an environment with a high density of invasive and, thus, infection-prone procedures. The 2 primary goals of this study were (1) to perform a precise analysis of anesthesia-related hand hygiene (HH) procedures and (2) to optimize HH compliance. METHODS: We conducted a prospective, triphase before/after study to determine opportunities for and compliance with hand disinfection (World Health Organization definition) in an anesthesia working area. Standard operating procedures were optimized for invasive procedures during 2 predefined intervention periods to improve work flow practices. RESULTS: Seven hundred fifty anesthesia procedures were evaluated with 12,142 indications for HH. Compliance significantly increased from 10% (465/4,636) to 30% (1,202/4,029) and finally to 55% (1,881/3,477; all P < .001) in phases I, II, and III, respectively. We identified a significant increase in the number of hand rubs performed during 1 anesthesia procedure (2 to 8, respectively; P < .001) in parallel with a significant decrease in number of opportunities needing a hand rub (24 to 14, respectively; P < .0001) because of improved work flow practices. Notably, the greatest improvement was seen before aseptic tasks (8% to 55%, respectively). CONCLUSION: Our study provides the first detailed data on anesthesia-related and indication-specific HH. Importantly, HH compliance improved significantly without a noticeable increasing workload.
    American journal of infection control 05/2013; · 3.01 Impact Factor
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    ABSTRACT: PURPOSE: In a previous observational intervention study, we achieved a more than 100 % increase in overall hand hygiene (HH) compliance in the hemodialysis setting by increasing the number of hand rubs (HR) performed and concomitantly optimizing HH standard operating procedures (SOPs). SOPs were mainly aimed at reducing the number of avoidable opportunities due to a less than perfect workflow. However, the long-term sustainability of this successful intervention was not evaluated. The present study was carried out to evaluate the long-term effects of our previous successful intervention. METHODS: We conducted a follow-up observational study 1 year after the first intervention study in the same hemodialysis unit to assess the sustainability. No HH-related interventions were performed in the 1 year between studies. The main outcome was HH compliance, and the secondary outcome was opportunities per hemodialysis procedure. RESULTS: A total of 1,574 opportunities for HH and 871 hand rubs (HR) were observed during the follow-up observational study. Overall, compliance was 55 %, which was significantly than that at the end of the first study (62 %; p < 0.0001), but significantly higher than that at the start and mid-term phases of the first study (37 and 49 %, p < 0.0001). Both the decrease in HH opportunities and the increase in HR were sustained over the course of this observational study. The number of avoidable opportunities in the present study was similar to that at the end of the previous study. Thus, in 320 opportunities (20 %), gloves were worn instead of HR performed, representing 46 % of all missed HR. CONCLUSIONS: Despite a decrease in HH compliance compared to the last postintervention period, a multifaceted intervention focusing on standardization and workflow optimization resulted in a sustained improvement in HH. We therefore propose that standardization of the hemodialysis workflow aimed at improving HH is a promising avenue for improving the quality of patient care and outcome.
    Infection 02/2013; · 2.44 Impact Factor
  • S. Scheithauer, S.W. Lemmen
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    ABSTRACT: Hand hygiene is considered to be the pillar of infection control and prevention. Despite national and international recommendations on hand hygiene, compliance remains low. Basic requirements allowing adequate hand hygiene compliance, in theory at least, are well known. Why then is it so hard to achieve acceptable compliance despite sufficient access to hand disinfectant dispensers, repeated training, and participation in national campaigns? Could it be that hand hygiene is regarded as too laborious, and changes to the established work-flow are needed to increase compliance? Some practicable examples are presented and pitfalls in defining compliance are discussed. Ownership for compliance must come from within clinical teams, and not solely driven from the infection control team. Support from the hospital management is essential. Ideally, the concepts presented allow a simple and efficient implementation of hand hygiene as part of the clinical work-flow to achieve an increase in compliance in the longer term.
    The Journal of hospital infection 02/2013; 83:S17–S22. · 3.01 Impact Factor
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    ABSTRACT: BACKGROUND: Surveillance for central line (CL)-associated bloodstream infections (CLABSIs) is generally advocated. However, the standard definition of this surveillance does not take into account the number of CLs in place and thus the possibility of increased infection risk with multiple CLs in place simultaneously. In this study, we tested the hypothesis that simultaneous placement of more than 1 CL is associated with an increased CLABSI rate. METHODS: The number of CLs, CL-days, and CLABSIs and CLABSI rates with regard to the number of CLs in place simultaneously was documented in 2 intensive care units between 2001 and 2011. Standard CLABSI rates, as well as the rates for 1 CL and multiple CLs in place, were calculated. RESULTS: The average CLABSI rate was significantly lower in patients with 1 CL in place compared with those with more than 1 CL in place (3.69 per 1,000 CL-days vs 13.09/1,000 CL-days; incidence rate ratio [IRR], 3.63; 95% confidence interval [CI], 2.61-5.05). Importantly, all differences from the standard rate (5.94/1,000 CL-days) were significant (1 CL vs standard: IRR, 0.61; 95% CI, 0.51-0.74; more than 1 CL vs standard: IRR, 2.23; 95% CI, 1.87-2.65; both P < .0001). CONCLUSIONS: Our data show that the number of CLs in place had a strong influence on CLABSI rates. Thus, we advocate stratifying patients by the number of CLs in place to take this increased risk of infection into account during surveillance.
    American journal of infection control 08/2012; · 3.01 Impact Factor
  • S Lemmen, K Lewalter
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    ABSTRACT: Fever is common in patients in intensive care units. Sources of fever can be infectious or non-infectious. The most common sources of infectious fever include ventilator-associated pneumonia, intravascular catheter-related infections, infection with Clostridium difficile or sinusitis. Typical examples of non-infectious fever include thromboembolic events, myocardial infarction, autoimmune disease, withdrawal symptoms or a drug-fever. Every new onset of fever prompts diagnostic decisions, treatment with antipyretics should be discussed critically.
    DMW - Deutsche Medizinische Wochenschrift 05/2012; 137(21):1123-5. · 0.65 Impact Factor
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    ABSTRACT: Despite several guidelines on hand hygiene (HH), compliance especially in physicians is reported to be low which has huge implications for healthcare-associated infections. To evaluate performance of HH, influence of teaching and influence of monitoring the results in medical students, we conducted an observational study. Performance of hand disinfection was evaluated in first (N=28), third (N=193) and fifth (N=45) year medical students using fluorescent hand disinfectant. The influence of teaching and information about result control was assessed. The students perception of the impact of HH was also evaluated by a questionnaire. Presence of disinfectant gaps was observed significantly more often in first year medical students compared to third year ones (82% vs, 60%; p=0.02). In additional, > 3 gaps were seen significantly more often in first year medical students compared to fifth year students (36% vs. 9%; p=0.007). Both information about teaching and monitoring the results improved outcome significantly. For example, gaps were present in 92% without information and without teaching, in 70% (RR: 1.3 (1.0-1.6); p=0.003) with information about result control only, and in only 18% (5.1 (3.0-8.5); p=0.0001) after teaching. Notably, the medical students ascribed HH to be of a great importance regardless of their level of education. Performance of HH could be improved by practical training as evidenced by best HH performance being documented immediately after teaching and a training effect during the course of medical studies was also observed. Thus, we suggest implementing regular education and practical training on HH from early on in the medical studies curricula to improve overall quality of patient care. regular education and practical training on HH from early on in the medical studies curricula to improve overall quality of patient care.
    International journal of hygiene and environmental health 03/2012; 215(5):536-9. · 2.64 Impact Factor
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    ABSTRACT: Periprosthetic knee joint infection is a rare complication. However, patients as well as surgeons have to deal with severe problems. The past years have brought new knowledge on periprosthetic knee joint infections which have resulted in new classifications. The present manuscript evaluates the current literature on this topic and presents a new therapeutic algorithm.
    Der Orthopäde 01/2012; 41(1):20-5. · 0.51 Impact Factor
  • S Scheithauer, H Häfner, S W Lemmen
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    ABSTRACT: Surgical site infections are mainly caused by bacteria from the patients' skin or gut flora representing endogenous infections. In orthopedic and trauma surgery the skin commensals dominate and as a consequence Gram-positive bacteria are the main pathogens, particularly S. aureus. Additionally and especially in the case of foreign body infections, less virulent pathogens, e.g. coagulase-negative staphylococci play an important role. Due to newer microbiological techniques in detecting pathogens the spectrum of causative organisms is steadily increasing. As known for other nosocomial infections the relevance of multidrug resistant bacteria in surgical site infections is growing and the key player is methicillin-resistant S. aureus (MRSA); however vancomycin-resistant enterococci (VRE), extended spectrum betalactamases and/or carbapenemases producing enterobacteria and recently even panresistant Acinetobacter baumannii isolates have to be considered.
    Der Orthopäde 01/2012; 41(1):6-10. · 0.51 Impact Factor
  • K Lewalter, S W Lemmen
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    ABSTRACT: Individual patient risk factors for wound infections, such as alcohol abuse, smoking or obesity can usually only be modified to a small extent. Studies have shown a reduction of surgical site infections due to the implementation of a benchmarking surveillance system. In order to prevent surgical site infections a variety of interventions are available, such as glucose control, correction of anemia and malnutrition and antibiotic therapy of infections before elective surgery. Reduction of the microbial skin flora by whole body washing procedures, avoidance of sharp razor shaving, application of antibiotic prophylaxis and correct surgical hand disinfection are additional measures. Intraoperative hypothermia should be avoided and strict compliance with asepsis is mandatory. Postoperative preventive measures include appropriate wound care and rapid removal of wound drainage.
    Der Orthopäde 01/2012; 41(1):11-4. · 0.51 Impact Factor
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    ABSTRACT: Chronic osteomyelitis is a severe complication characterized by soft tissue and bone pathogenic infection resulting in osseous destruction. Surgical management is demanding and poses a challenge in achieving the goals of treatment, which are control of infection, bone healing as well as satisfactory functional outcome. Therapeutic strategies are based on a combined application of radical surgery and systemic antibiotic therapy. The bony defects which remain after extensive debridement have to be reconstructed with bone grafting after soft tissue coverage and the healing process is decisive for a successful outcome.
    Der Orthopäde 01/2012; 41(1):43-50. · 0.51 Impact Factor
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    ABSTRACT: This review focuses on the presentation of the diagnostic and therapeutic principles for treatment of chronic osteomyelitis of long bones in adults. Early detection of the offending bacteria is a crucial step which has to be performed with tissue and fluids from the depth of the wound. Superficial samples and swaps from fistulas should be avoided and are not considered to be representative. Chronic osteomyelitis is characterized by necrotic and nonvascularized bony tissue which represents one of the most relevant sources for recurrence infection. Appropriate therapy includes radical excision of the diseased bone and infected scar tissue, closure of the wound with well-vascularized (muscle) flaps, stabilization, and administration of adequate antibiotics.
    Der Unfallchirurg 01/2012; 115(1):55-66. · 0.64 Impact Factor
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    ABSTRACT: Zusammenfassung Gegenstand der vorliegenden Übersichtsarbeit ist die Darstellung der diagnostischen und the-rapeutischen Prinzipien bei der Behandlung der chronischen Osteomyelitis der langen Röh-renknochen im Erwachsenenalter. Wichtig ist eine möglichst frühzeitige Keimbestimmung aus dem Gewebe, das im Rahmen einer Biopsie oder eines Débridements aus der Tiefe ge-wonnen wird. Oberflächliche Abstriche oder solche aus Fistelgängen sind nicht aussagekräf-tig und sollten deshalb zur Planung der antibiotischen Therapie nicht herangezogen werden. Die chronische Osteomyelitis ist durch nekrotisches bzw. nichtdurchblutetes Knochengewe-be gekennzeichnet, das eine Hauptgefahr für das Wiederaufflackern von Infektionen darstellt. Hier kann nur eine multimodale Therapie bestehend aus chirurgischer Sanierung mit sorg-fältiger Resektion von nicht durchblutetem Gewebe (radikale Nekrektomie), einer gut vasku-larisierten weichteiligen Deckung, Stabilisierung und einer gezielten (rationalen) antibioti-schen Therapie zum Erfolg führen.
    01/2012; 115:55-66.
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    ABSTRACT: Haemodialysis patients are at high risk for developing healthcare-associated infections as well as acquiring multidrug-resistant microorganisms. Hand hygiene is considered to be the single most effective tool to prevent healthcare-associated infections. The number of indications and the extent of indication-specific compliance with hand rubs in the haemodialysis setting are currently unknown. We conducted a prospective, three-phase, observational intervention study on hand hygiene during haemodialysis treatments. Optimized hand hygiene standard operating procedures (SOPs) for dialysis connections (Intervention I) and disconnections (Intervention II) were compiled and implemented during two predefined intervention periods. A total of 8897 indications for hand rubs were observed throughout this study. In the course of the study, we identified an increase in the number of hand rubs performed (6-9, mean number per dialysis procedure), parallelled by a decrease in the indications for hand rubs (21-15), resulting in a significant increase of overall hand rub compliance (30-62%). The greatest improvement was seen before aseptic tasks (21-52%), the indication with the greatest impact on preventing healthcare-associated infections. There was no difference between haemodialysis via central venous catheter access or arterio-venous (AV) fistulas. This study provides the first detailed data on the number of and indications for hand rubs during dialysis. An >100% increase in overall hand hygiene compliance could be achieved by a comparably moderate increase in hand rubs performed in combination with optimized hand hygiene SOPs.
    Nephrology Dialysis Transplantation 07/2011; 27(2):766-70. · 3.37 Impact Factor

Publication Stats

378 Citations
113.42 Total Impact Points


  • 2000–2014
    • University Hospital RWTH Aachen
      • Department of Neurology
      Aachen, North Rhine-Westphalia, Germany
  • 2001–2012
    • RWTH Aachen University
      • • Central Unit of Hospital Hygiene and Infectious Diseases
      • • Institut für Medizinische Mikrobiologie
      Aachen, North Rhine-Westphalia, Germany
  • 2010
    • Universitätsklinikum Freiburg
      • Department of Environmental Health Sciences
      Freiburg, Lower Saxony, Germany