Investigating a possible link between antiseptic treatment and the increased occurrence of daptomycin-resistant Staphylococcus aureus.

OBJECTIVES: Because of a steady increase in the detection of daptomycin-resistant (DAP-R) Staphylococcus aureus at three medical centres in Cologne, Germany, molecular surveillance was established from June 2016 to June 2018 to investigate the causes of the emergence and spread of respective isolates. Seventy-five S. aureus isolates, both DAP-R and DAP-susceptible, were collected from 42 patients for further analysis. METHODS: Broth microdilution was used to determine the MICs for DAP and polyhexamethylene biguanide/polyhexanide (PHMB). To investigate the effect of PHMB on the development of DAP resistance, we performed selection experiments with PHMB. All isolates studied were subjected to whole-genome sequencing. Epidemiological, clinical, microbiological and molecular data were analysed comparatively. RESULTS: Acquisition of DAP resistance was mainly observed in patients with acute and chronic wounds (40/42, 96.2%) treated with antiseptic (32/42, 76.2%) rather than systemic antibiotic therapy using DAP or vancomycin (7/42, 16.7%). DAP-R S. aureus had a diverse genetic background; however, within individual patients, isolates were closely related. At least three potential transmission events were detected. Most DAP-R isolates had concomitant elevated MICs for PHMB (50/54, 92.6%), and in vitro selection experiments confirmed that PHMB treatment is capable of generating DAP resistance. DAP resistance could be linked to 12 different polymorphisms in the mprF gene in the majority of clinical isolates (52/54, 96.3%) as well as in all in vitro selected strains. DISCUSSION: DAP resistance in S. aureus can occur independently of prior antibiotic therapy and can be selected by PHMB. Therefore, wound treatment with PHMB may trigger individual resistance development associated with gain-of-function mutations in the mprF gene.

Standardized aseptic dressing change procedure: Optimizations and adherence in a prospective pre- and postintervention cohort study.

BACKGROUND: The "HygArzt" project investigated the effectiveness of hygiene measures introduced by an infection prevention link physician (PLP). OBJECTIVE: To investigate whether the introduction of a standardized aseptic dressing change concept (ADCC) by a PLP can increase hand hygiene adherence and adherence to specific process steps during an aseptic dressing change (ADC) in a trauma surgery and orthopedic department. METHODS: We defined 4 required hand disinfection indications: (1) before the preparation of ADC equipment, (2) immediately before the ADC, (3) before the clean phase, and (4) after the ADC. A process analysis of the preintervention phase (331 ADCs) was used to develop a standardized ADCC. The ADCC was introduced and iteratively adopted during the intervention phase. The effect was evaluated during the postintervention phase (374 ADCs). RESULTS: Hand hygiene adherence was significantly increased by the introduction of the ADCC for all indications: (1) before the preparation of the ADC equipment (from 34% before to 85% after, P <.001), (2) immediately before an ADC (from 32% before to 85% after; P < .001), (3) before the clean phase (from 42% before to 96% after; P < .001), and (4) after an ADC (from 74% before to 99% after; P < .001). Overall hand hygiene adherence was analyzed before the indications for an ADC (from 9.6% before to 74% after; P < .001). The same strategy was applied to the following process parameters: use of a clean work surface, clean withdrawal of equipment from the dressing trolley, and appropriate waste disposal. CONCLUSIONS: A PLP sufficiently implemented a standardized concept for aseptic dressing change during an iterative improvement process, which resulted in a significant improvement in hand hygiene and adherence to other specific ADCC process steps.

Evidence of the medical and economic benefits of implementing hygiene measures by a prevention link physician in trauma surgery: Study protocol for a biphasic multicenter prospective interventional pre-post cohort study using a structured intervention bundle development and tools of behavior change management.

INTRODUCTION: The German Commission for Hospital Hygiene and Infection Prevention recommends nominating one authorized medical specialist in every medical department as an infection prevention link physician (PLP). It has been roughly described that a PLP serves as a link between the infection prevention team and the respective clinical departments. No detailed evidence about the contribution made by PLPs to the decrease of infection rates is available in Germany. The "HygArzt" project aims to demonstrate the medical and economic benefits of the implementation of hygiene measures by PLP in trauma surgery/orthopedics. METHODS: A multicenter interventional pre/post cohort study design was chosen. The study will run for a three-year period, including a pre-, post-, and an intervention phase, in four different hospitals, one of which will serve as pilot. A complex intervention containing evidence-based infection control measures will be developed and implemented by a PLP to proof efficacy. After the successful implementation of the preventive measures in the pilot hospital, the concept will be transposed to the three remaining trauma and orthopedic departments to confirm the transferability and generalizability. To enable the PLPs of the non-pilot departments, a subject-specific training program will be developed based on the study results of the pilot hospital and offered to the PLPs. DISCUSSION: Data are intended to provide evidence that and, if so, to which extent the implementation of specific preventive measures by a medical department-specific PLP is possible and results in a reduction of nosocomial infections in orthopedic surgery and traumatology. CONTRIBUTION TO THE LITERATURE: The present study describes a novel complex study design to prove the effectiveness of intervention measures for infection prevention. The study design and newly developed methodological approach could serve as a model for similar studies on infection prevention in the future. For the first time, the presented research project "HygArzt" focuses on the implementation of hygiene measures by an infection prevention link physician (PLP) and investigates whether nosocomial infections, especially surgical site infections, can be reduced by the measures implemented. TRIAL REGISTRATION: German clinical Trials register DRKS-ID:00013,296. Registered on March 5, 2018, https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00013296.

Implementation methods of infection prevention measures in orthopedics and traumatology - a systematic review.

BACKGROUND: Prevention of hospital-acquired infections, in the clinical field of orthopedics and traumatology especially surgical site infections, is one of the major concerns of patients and physicians alike. Many studies have been conducted proving effective infection prevention measures. The clinical setting, however, requires strategies to transform this knowledge into practice. QUESTION/PURPOSE: As part of the HYGArzt-Project ("Proof Of Effectivity And Efficiency Of Implementation Of Infection Prevention (IP) Measures By The Physician Responsible For Infection Prevention Matters In Traumatology/Orthopedics"), the objective of this study was to identify effective implementation strategies for IP (infection prevention) measures in orthopedics and trauma surgery. METHODS: The systematic review was conducted following PRISMA guidelines. A review protocol was drafted prior to the literature search (not registered). Literature search was performed in MEDLINE, SCOPUS and COCHRANE between January 01, 1950 and June 01, 2019. We searched for all papers dealing with infection and infection control measures in orthopedics and traumatology, which were then scanned for implementation contents. All study designs were considered eligible. Exclusion criteria were language other than English or German and insufficient reporting of implementation methods. Analyzed outcome parameters were study design, patient cohort, infection prevention measure, implementation methods, involved personnel, reported outcome of the studies and study period. RESULTS: The literature search resulted in 8414 citations. 13 records were eligible for analysis (all published between 2001 and 2019). Studies were primarily prospective cohort studies featuring various designs and including single IP measures to multi-measure IP bundles. Described methods of implementation were heterogeneous. Main outcome parameters were increase of adherence (iA) to infection prevention (IP) measures or decrease in surgical site infection rate (dSSI%). Positive results were reported in 11 out of 13 studies. Successful implementation methods were building of a multidisciplinary team (considered in 8 out of 11 successful studies [concerning dSSI% in 5 studies, concerning iA in five studies]), standardization of guidelines (considered in 10/11 successful studies [concerning dSSI% in 5 studies, concerning iA in seven studies]), printed or electronic information material (for patient and/or staff; considered in 9/11 successful studies [concerning dSSI% 4/4, concerning iA 5/5]), audits and regular meetings, personal training and other interactive measures as well as regular feedback (considered in 7/11 successful studies each). Personnel most frequently involved were physicians (of those, most frequently surgeons) and nursing professions. CONCLUSION: Although evidence was scarce and quality-inconsistent, we found that adhering to a set of implementation methods focusing on interdisciplinary and interactive /interpersonal work might be an advisable strategy when planning IP improvement interventions in orthopedics and traumatology.

Adherence to personal protective equipment use among healthcare workers caring for confirmed COVID-19 and alleged non-COVID-19 patients.

Adherence observations of health care workers (HCW) revealed deficiencies in the use of recommended personal protective equipment (PPE) among HCW caring in COVID-19 and non-COVID-19 wards during the first period of the SARS-CoV-2 pandemic in a university hospital in Germany. The adherence to wearing surgical face or FFP2-masks and disinfecting hands prior to donning and after doffing the PPE was significantly higher in COVID-19 wards However, there was no total adherence of 100% in COVID-19 wards.

Vancomycin-soaking of the graft reduces the incidence of septic arthritis following ACL reconstruction: results of a systematic review and meta-analysis.

PURPOSE: (1) To compare the incidence of post-operative septic arthritis following anterior cruciate ligament reconstruction (ACLR) between patients receiving routine pre-operative intravenous (IV) prophylaxis only intravenous (IV) infection prophylaxis and patients receiving additional graft-soaking in a vancomycin solution (5 mg/ml) perioperatively. (2) To review the literature regarding effects of graft-soaking in vancomycin solutions on outcomes, complication rates and tendon properties in ACLR. METHODS: To identify studies pertaining to routine pre-operative IV prophylaxis and additional usage of intra-operative vancomycin-soaked grafts in primary ACLR, the Cochrane Library, SCOPUS and MEDLINE were searched till June 2018 for English and German language studies of all levels of evidence following the PRISMA guidelines. Additionally, all accepted abstracts at the ESSKA 2018, ISAKOS 2017, AGA 2017 and AOSSM 2017 meetings were screened. Data regarding the incidence of septic arthritis were abstracted and combined in a meta-analysis. Data including outcome scores, complication rates and in vitro analyses of tendon properties were collected and summarized descriptively. RESULTS: Upon screening 785 titles, 8 studies were included. These studies examined 5,075 patients following ACLR and followed from 6 to 52 weeks post-operatively. Of those 2099 patients in the routine pre-operative IV prophylaxis group, 44 (2.1%) cases of early septic arthritis were reported. In contrast, there were no reports of septic arthritis following ACLR in 2976 cases of vancomycin-soaked grafts. The meta-analysis yielded an odds ratio of 0.04 (0.01-0.16) favouring the addition of intra-operative vancomycin-soaking of grafts. Across all available studies, no differences in clinical outcome (i.e. incidence of ACL revision, IKDC score, Tegner score), biomechanical tendon properties, or cartilage integrity between patients with and without vancomycin-soaked grafts were identified. CONCLUSION: The incidence of septic arthritis following ACLR can be reduced dramatically by vancomycin-soaking the grafts intra-operatively prior to graft passage and fixation. Within the limitation confines of this study, intra-operative graft-soaking in vancomycin appears to be a safe and effective method to reduce the incidence of septic arthritis following ACLR. Still, it remains debatable if the available data facilitate the recommendation for a universal application of vancomycin-soaking for all ACLR patients or if it should be reserved for patients at risk, including the use hamstring tendons, revision cases and in the presence of medical preconditions. LEVEL OF EVIDENCE: Level IV, systematic review of Level III and Level IV studies.

High prevalence of bacteria in clinically aseptic non-unions of the tibia and the femur in tissue biopsies.

PURPOSE: There are several hints that bacterial colonization might be an often overseen cause of non-union. Modern procedures like PCR have been reported to diagnose bacterial colonization with a high degree of accuracy. While PCR is not ubiquitously available, we hypothesize that biopsies from the non-union site are comparable to PCR results reported in the literature. METHODS: Retrospective analysis of microbiological results of biopsies from non-unions (femoral or tibial, history of revision surgery, and/or open fracture) with stable osteosynthesis, no clinical signs of local infection were analysed. CRP and leucocyte count were taken on admission. Multiple tissue samples (soft tissue and bone) were from the non-union (1-4 cm incision). Samples were cultivated for 2 weeks and tested following EUCAST protocols using VITEK® 2. RESULTS: 11 tibia- and 7 femur non-union (44 ± 23.9 years), 11 open fractures (1 I°, 6 II°, 4 III° Gustillo Anderson), 0-5 revisions, and 4.1 (± 1.8) tissue samples were taken 8.5 (± 1.7) months after trauma. Cultures were positive in 8/18 (44,4%) (3/18 Propionibacterium acnes, 1/18 S. capitis, and 4/18 S. epidermidis). There was neither a correlation between number of biopsies taken and positive culture results (Pearson R: - 0.0503, R2 0.0025), nor between positive culture results and leucocytes counts (Pearson R: - 0.0245, R2 0.0006) or CRP concentration (Pearson R: 0.2823, R2 0.0797). CONCLUSION: The results confirm that the presence of bacteria in cases with no clinical signs of infection is a relevant issue. The prevalence of bacteria reported here is comparable that reported from cohorts tested with PCR or sonication. In most cases, there was only one positive biopsy, raising the question whether a contamination has been detected. Thus, to better understand the problem, it is necessary to gather more knowledge regarding the sensitivities and specificities of the different diagnostic procedures.

Effective Graft Preservation by Following a Standard Protocol for the Treatment of Knee Joint Infection after Anterior Cruciate Ligament Reconstruction.

Knee joint infections constitute a rare but devastating complication after anterior cruciate ligament (ACL) reconstruction. We hypothesized that effective infection therapy and graft preservation is possible following a standard treatment protocol. We retrospectively analyzed all patients admitted to our center with suspected infection of the knee after ACL reconstruction between 2010 and 2012. Following a standardized protocol, blood samples were drawn and synovial fluid was analyzed. Furthermore, the protocol consisted of arthroscopic lavages and debridements of the anterior and posterior joint compartments over three incisions, and targeted antibiotic therapy over a period of 6 weeks. Surgeries were repeated every 2 days until clinical signs of infections resolved, but at least two times. Mean observation period was 10 months. Forty-one patients aged 31 ( ± 9.9) years and admitted 14 ( ± 7.5) days after ACL reconstruction were included. Pathogens were found in 34 patients and coagulase-negative staphylococci were isolated most commonly (31 isolates in 28 patients). Quinolones were the most commonly used antibiotic agents. Mean number of operations was 3.8 ( ± 1.4). Following the standard protocol, primary successful infection treatment with graft preservation was possible in 37 of the included 41 patients. Graft preservation was achieved in 100% of the included patients with Gaechter stage 1 and 2 infections. Knee joint infection after ACL reconstruction was successfully treated following a standardized protocol, and graft preservation was reliably achieved especially in cases with infections at an early stage.

One-year molecular surveillance of carbapenem-susceptible A. baumannii on a German intensive care unit: diversity or clonality.

Background: A. baumannii is a common nosocomial pathogen known for its high transmission potential. A high rate of carbapenem-susceptible Acinetobacter calcoaceticus-Acinetobacter baumannii (ACB)-complex in clinical specimens led to the implementation of a pathogen-based surveillance on a 32-bed surgical intensive care unit (SICU) in a German tertiary care centre. Methods: Between April 2017 and March 2018, ACB-complex isolates with an epidemiological link to the SICU were further assessed. Identification to the species level was carried out using a multiplex PCR targeting the gyrB gene, followed by RAPD, PFGE (ApaI) and whole genome sequencing (WGS, core genome MLST, SeqSphere+ software, Ridom). Additional infection prevention and control (IPC) measures were introduced as follows: epidemiological investigations, hand hygiene training, additional terminal cleaning and disinfection incl. UV-light, screening for carbapenem-susceptible A. baumannii and environmental sampling. Hospital-acquired infections were classified according to the CDC definitions. Results: Fourty four patients were colonized/infected with one or two (different) carbapenem-susceptible ACB-complex isolates. Fourty three out of 48 isolates were classified as hospital-acquired (detection on or after 3rd day of admission). Nearly all isolates were identified as A. baumannii, only four as A. pittii. Twelve patients developed A. baumannii infections. Genotyping revealed two pulsotype clusters, which were confirmed to be cgMLST clonal cluster type 1770 (n = 8 patients) and type 1769 (n = 12 patients) by WGS. All other isolates were distinct from each other. Nearly all transmission events of the two clonal clusters were confirmed by conventional epidemiology. Transmissions stopped after a period of several months. Environmental sampling revealed a relevant dissemination of A. baumannii, but only a few isolates corresponded to clinical strains. Introduction of the additional screening revealed a significantly earlier detection of carbapenem-susceptible A. baumannii during hospitalization. Conclusions: A molecular and infection surveillance of ACB-complex based on identification to the species level, classic epidemiology and genotyping revealed simultaneously occurring independent transmission events and clusters of hospital-acquired A. baumannii. This underlines the importance of such an extensive surveillance methodology in IPC programmes also for carbapenem-susceptible A. baumannii.

Fluoroscopic control allows for precise tunnel positioning in MPFL reconstruction.

PURPOSE: In MPFL reconstruction, anatomical graft positioning is required to restore physiological joint biomechanics and patellofemoral stability. Considerable rates of non-anatomical femoral tunnel placement exist. The purpose of this study was to analyse whether intraoperative fluoroscopic control is applicable to reduce variability of femoral tunnel positioning. METHODS: Femoral tunnel positions of 116 consecutive MPFL reconstructions applying intraoperative fluoroscopic images were analysed. Tunnel positions were determined by two independent observers according to Schöttle's radiographic measurement method. Mean positions, standard deviations and ranges were calculated to determine the variability of the tunnel positions. Interclass correlation coefficient (ICC) was calculated. RESULTS: The mean anterior/posterior distances from the anatomical insertion of the MPFL to the centre of the femoral tunnel were 2.34 mm (range 0.0-5.9 mm) and 1.7 mm (range 0.1-7.3 mm, SD 1.3) for proximal/distal deviations; 95.7 % (111/116) of femoral tunnel positions were found to be within the anatomical insertion area defined by Schöttle. Interobserver tunnel position measurements were highly reliable (ICC: depth 0.979; height 0.979). CONCLUSION: The study demonstrates that intraoperative fluoroscopic control is a feasible and effective method that enables to create reproducible and precise anatomical femoral tunnel positions in MPFL reconstruction. Accordingly, the routine use of intraoperative fluoroscopy can be recommended. Furthermore, the results indicate Schöttle's method as a reliable method for intraoperative control and postoperative analysis of femoral tunnel positioning. LEVEL OF EVIDENCE: IV.

Current status of ACL reconstruction in Germany.

INTRODUCTION: Reconstruction of the anterior cruciate ligament (ACL) is characterized by a variety of possibilities concerning its implementation. Different choices for grafts, fixation methods and tunnel positioning, as well as diverse technical tools are available and have clinical significance. Besides specific pre- and post-operative procedures, different indications for surgery and further surgeon-/clinic-related factors add variability to the treatment. In response to the lack of descriptive statistics about the implementation of these factors and the increasing numbers of ACL reconstructions this study has been conducted to display the current state of the treatment for ACL tears throughout Germany. MATERIALS AND METHODS: 709 clinics with surgical and orthopedic departments were provided an online-questionnaire that surveyed their statistical records (e.g. annually implemented operations, number of surgeons, duration of operations), implemented techniques (e.g. choice of grafts, construction of drilling tunnel, tibial/femoral fixation) and personal assessment (e.g. frequency/cause of graft failure, frequency/handling of infection). The response rate was 22 % (n = 155). Based on the statistical records a specialized group within the respondents was identified, enabling a cross-comparison between high- and low-volume surgeons. RESULTS: On average, the German orthopedic surgeons in the clinics surveyed annually performs 35 ACL reconstructions, with each operation lasting an average of 67 min. After subdividing the data with references to annually performed surgeries into high- and low-volume-surgeons, differences and common features between the subgroups become apparent. Differences between high- and low-volume-surgeons, respectively, show shorter duration of both ACL reconstructions (55 vs. 71 min) and revision ACL reconstructions (75 vs. 90 min), higher membership rates in professional associations (83 vs. 38 % have at least one membership), more frequent implementation of stability examinations (47 vs. 21 %) and different frequencies of femoral drilling techniques (using the anterolateral portal in 71 vs. 54 %). With reference to evaluating operation dates, choosing grafts and assessing reasons for graft failure both groups share commonalities, as well as regarding the predominant use of monofixation for femoral fixation (88 % of the participants-mainly with endobutton in 38 % and transfixation pin in 27 %) and for tibial fixation (81 % of the participants-mainly with bioabsorbable screw in 60 %). CONCLUSIONS: The treatment of ACL tears in the group of German clinics studied is characterized by a variety of surgical possibilities. This condition might reflect the entirety of clinics reconstructing ACL in Germany. For the first time, a descriptive statistical survey was implemented to display this variety and to provide insight into the current status quo. Within the entirety of surgeons implementing ACL reconstruction a specialized subgroup with a particular expertise seems to exist.

Bacterial contamination of open fractures - pathogens, antibiotic resistances and therapeutic regimes in four hospitals of the trauma network Cologne, Germany.

INTRODUCTION: The bacterial contamination of soft tissues and bone in open fractures leads to an infection rate of up to 50%. Pathogens and their resistance against therapeutic agents change with time and vary in different regions. In this work, our aims were to characterize the bacterial spectrum present in open fractures, analyze the bacterial resistance to antibiotic agents and question the EAST guideline recommendations for antibiotic prophylaxis after open fractures in a German Trauma Network. MATERIALS AND METHODS: We conducted a retrospective cohort study and included all patients with open fractures from 1(st) of January 2011 until the 31(st) of December 2014 in four hospitals of the trauma network cologne. Soft tissue damage was classified according to the Gustilo Anderson classification. RESULTS: We included 123 patients. Forty-five injuries (37%) were classified I°, 45 (37%) as II° and 33 (27%) as III°. Lower leg (34%) was the most commonly injured location. An antibiotic prophylaxis was administered to 109 patients (89%). In 107 of them (98%) a cephalosporin or cephalosporin combination was given. In 35 of the patients (28%), microbiological samples were taken of the fracture site. Wound cultures were positive in 21 patients (60%). Fifty percent of the bacterial detections occurred in III° fractures. Coagulase negative Staphylococci (COST) were the most frequent pathogens. In II° open fractures one gram-negative strain was isolated. Fewest resistances were seen against quinolones and co-trimoxazole. DISCUSSION: The recommended EAST guideline prophylaxis would have covered all but one bacterium (97% of positive cultures). One Escherichia coli was found in a II° open fracture and would have been missed. One of the isolated Staphylococci epidermidis and an Enterococcus faecium were resistant against gentamycin and first- and second-generation-cephalosporin's which were used as prophylaxis frequently. However, a regional adaption of the EAST guidelines seems not justified due to the rather low number of cases in our study. CONCLUSION: The EAST guideline seems to be adequate in a high percentage of cases (97%) in the setting of the trauma network cologne. Further research should be guided at identification of initial open fracture pathogens to improve the efficiency of antibiotic prophylaxis.

Less than full circumferential fusion of a tibial nonunion is sufficient to achieve mechanically valid fusion--proof of concept using a finite element modeling approach.

BACKGROUND: Although minimally invasive approaches are widely used in many areas of orthopedic surgery nonunion therapy remains a domain of open surgery. Some attempts have been made to introduce minimally invasive procedures into nonunion therapy. However, these proof of concept studies showed fusion rates comparable to open approaches never gaining wider acceptance in the clinical community. We hypothesize that knowledge of mechanically relevant regions of a nonunion might reduce the complexity of percutaneous procedures, especially in complex fracture patterns, and further reduce the amount of cancellous bone that needs to be transplanted. The aim of this investigation is to provide a proof of concept concerning the hypothesis that mechanically stable fusion of a nonunion can be achieved with less than full circumferential fusion. METHODS: CT data of an artificial tibia with a complex fracture pattern and anatomical LCP are converted into a finite element mesh. The nonunion area is segmented. The finite element mesh is assigned mechanical properties according to data from the literature. An optimization algorithm is developed that reduces the number of voxels in the non union area until the scaled von Mises stress in the implant reaches 20% of the maximum stress in the implant/bone system that occurs with no fusion in the nonunion area at all. RESULTS: After six iterations of the optimization algorithm the number of voxels in the nonunion area is reduced by 96.4%, i.e. only 3.6% of voxels in the non union area are relevant for load transfer such that the von Mises stress in the implant/bone system does not exceed 20% of the maximal scaled von Mises stress occurring in the system with no fusion in the non union area at all. CONCLUSIONS: The hypothesis that less than full circumferential fusion is necessary for mechanical stability of a nonunion is confirmed. As the model provides only qualitative information the observed reduction of fusion area may not be taken literally but needs to be calibrated in future experiments. However this proof of concept provides the mechanical foundation for further development of minimally invasive approaches to delayed union and nonunion therapy.