A.-C. Breier

Influence of laminar airflow on prosthetic joint infections: a systematic review

BACKGROUND Many hospitals use ultraclean ventilation (UVC), also known as laminar airflow systems (LAF), in their operating rooms to decrease rates of surgical site infections (SSIs). However, the evidence for these systems is limited and the additional expenses for LAF are substantial. AIM To determine the effectiveness of LAF to decrease SSI rates following hip and knee prosthesis. METHODS Systematic review of cohort studies investigating the influence of LAF on SSIs following hip and knee prosthesis published during the last 10 years. FINDINGS Four cohort studies using the endpoint severe SSI following knee prosthesis and four studies following hip prosthesis were included. No individual study showed a significant benefit for LAF following knee prosthesis but one small study showed a significant benefit following hip prosthesis. However, one individual study showed significantly higher severe SSI rates following knee prosthesis and three studies significantly higher SSI rates following hip prosthesis under LAF conditions. The summary odds ratio was 1.36 (95% confidence interval: 1.06-1.74) for knee prosthesis and 1.71 (1.21-2.41) for hip prosthesis. CONCLUSIONS It would be a waste of resources to establish new operating rooms with LAF, and questionable as to whether LAF systems in existing operating rooms should be replaced by conventional ventilation systems.

Laminar airflow ceiling size: no impact on infection rates following hip and knee prosthesis.

OBJECTIVE Laminar airflow (LAF) systems are widely used, at least in orthopedic surgery. However, there is still controversial discussion about the influence of LAF on surgical site infection (SSI) rates. The size of the LAF ceiling is also often a question of debate. Our objective is to determine the effect of this technique under conditions of actual rather than ideal use. DESIGN Cohort study using multivariate analysis with generalized estimating equations method. SETTING Data for hip and knee prosthesis procedures from hospitals participating in the German national nosocomial infection surveillance system (KISS) from July 2004 to June 2009 were used for analysis. PATIENTS A total of 33,463 elective hip prosthesis procedures due to arthrosis (HIP-A) from 48 hospitals, 7,749 urgent hip prosthesis procedures due to fracture (HIP-F) from 41 hospitals, and 20,554 knee prosthesis (KPRO) procedures from 38 hospitals were included. METHODS The data were analyzed for hospitals with and without LAF in the operating rooms and by the size of the LAF ceiling. The endpoints were severe SSI rates. RESULTS The overall severe SSI rate was 0.74 per 100 procedures for HIP-A, 2.39 for HIP-F, and 0.63 for KPRO. For all 3 prosthesis types, neither LAF nor the size of the LAF ceiling was associated with lower infection risk. CONCLUSIONS The data demonstrate consistency and reproducibility with the results from earlier registry studies. Neither LAF nor ceiling size had an impact on severe SSI rates.

Epidemiology of healthcare associated infections in Germany: Nearly 20 years of surveillance

OBJECTIVE To describe the epidemiology of healthcare-associated infections (HAI) in hospitals participating in the German national nosocomial infections surveillance system (KISS). METHOD The epidemiology of HAI was described for the surveillance components for intensive care units (ITS-KISS), non-ICUs (STATIONS-KISS), very low birth weight infants (NEO-KISS) and surgical site infections (OP-KISS) in the period from 2006 to 2013. In addition, risk factor analyses were performed for the most important infections of ICU-KISS, NEO-KISS and OP-KISS. RESULTS Data from a total of 3,454,778 ICU patients from 913 ICUs, 618,816 non-ICU patients from 142 non-ICU wards, 53,676 VLBW from 241 neonatal intensive care units (NICU) and 1,005,064 surgical patients from operative departments from 550 hospitals were used for analysis. Compared with baseline data, a significant reduction of primary bloodstream infections (PBSI) and lower respiratory tract infections (LRTI) was observed in ICUs with the maximum effect in year 5 (or longer participation) (incidence rate ratio 0.60 (CI95 0.50-0.72) and 0.61 (CI95 0.52-0.71) respectively). A significant reduction of PBSI and LRTI was also observed in NEO-KISS when comparing the baseline situation with the 5th year of participation (hazard ratio 0.70 (CI95 0.64-0.76) and 0.43 (CI95 0.35-0.52)). The effect was smaller in operative departments after the introduction of OP-KISS (OR 0.80; CI95 0.64-1.02 in year 5 or later for all procedure types combined). Due to the large database, it has not only been possible to confirm well-known risk factors for HAI, but also to identify some new interesting risk factors like seasonal and volume effects. CONCLUSIONS Participating in a national surveillance system and using surveillance data for internal quality management leads to substantial reduction of HAI. In addition, a surveillance system can identify otherwise not recognized risk factors which should - if possible - be considered for infection control management and for risk adjustment in the benchmarking process.

Regional distribution of nosocomial infections due to ESBL-positive Enterobacteriaceae in Germany: data from the German National Reference Center for the Surveillance of Nosocomial Infections (KISS)

Surveillance systems for hospital infections are reporting increasing rates of extended-spectrum β-lactamase (ESBL)-positive Enterobacteriaceae in Europe. We aimed to perform a national survey on this trend and on the regional distribution of nosocomial infections due to ESBL-positive Enterobacteriaceae in German hospitals. Data from 2007 to 2012 from two components of the German national nosocomial infection surveillance system were used for this analysis. The data derive from intensive care units and surgical departments. Independent factors determining the proportion of ESBL-positive Enterobacteriaceae among nosocomial infections due to Enterobacteriaceae and changes in its regional distribution (broken down into German federal states) were calculated by regression analysis. From 2007 to 2012, the data showed a significantly increasing proportion of ESBL-positive Enterobacteriaceae in surgical site infections (from 11.46 to 15.38, 134%, p 0.003), urinary tract infections (9.36 to 16.56, 177%, p <0.001) and lower respiratory tract infections (11.91 to 14.70, 123%, p <0.001) due to Enterobacteriaceae. Factors independently associated with a growing proportion were: Thuringia (p 0.009; odds ratio (OR) 1.53), North Rhine-Westphalia (p <0.001; OR 1.41) and general surgery ward (p 0.002; OR 1.47). The proportion of ESBL-positive Enterobacteriaceae in nosocomial infections has significantly increased in Germany over the last 6 years. Hospitals in Central Germany and surgical departments in all of Germany are especially affected by this development.

Prolonged duration of operation: an indicator of complicated surgery or of surgical (mis)management?

PurposeThe aim of this study was to investigate whether a prolonged operative time should be regarded as an indicator of quality problems in operating rooms or as patient-specific risk factors when analyzing surgical site infection (SSI) rates.MethodData from the SSI component of the German national nosocomial infection surveillance system (KISS) were used to address this question. Eight procedure categories tracked by at least 30 departments participating in KISS were included in the analysis, namely, hip (2 types) and knee prosthesis, breast surgery, hernia repair, C-section, cholecystectomy and colon operations. Various multiple logistic regression analyses were performed for each procedure category to predict duration of operation. Patient factors (sex, age, American Society of Anesthesiologists score, wound contamination class) and hospital factors (hospital status, size, annual volume) were considered. The area under the receiver operating characteristic (ROC) curve was used to evaluate predictive power including patient- and hospital-based factors.ResultsA total of 253,454 operations were included in the analysis. In general, the predictive power of the model including all variables for the different procedure types was relatively low (C-index range: 0.57–0.63) and not much higher than that of the models including only patient-based or only hospital-based variables, respectively. The predictive power for the duration of operative time based on the model including only hospital-based variables was as good as or better than that of the model including only patient-based factors.ConclusionDuration of operation is at least partially determined by hospital factors and, consequently, should be used as a quality indicator to compare SSI infections between hospitals, rather than being used as a patient factor to adjust comparisons between hospitals.

Agreement among Healthcare Professionals in Ten European Countries in Diagnosing Case-Vignettes of Surgical-Site Infections

Objective Although surgical-site infection (SSI) rates are advocated as a major evaluation criterion, the reproducibility of SSI diagnosis is unknown. We assessed agreement in diagnosing SSI among specialists involved in SSI surveillance in Europe. Methods Twelve case-vignettes based on suspected SSI were submitted to 100 infection-control physicians (ICPs) and 86 surgeons in 10 European countries. Each participant scored eight randomly-assigned case-vignettes on a secure online relational database. The intra-class correlation coefficient (ICC) was used to assess agreement for SSI diagnosis on a 7-point Likert scale and the kappa coefficient to assess agreement for SSI depth on a three-point scale. Results Intra-specialty agreement for SSI diagnosis ranged across countries and specialties from 0.00 (95%CI, 0.00–0.35) to 0.65 (0.45–0.82). Inter-specialty agreement varied from 0.04 (0.00–0.62) in to 0.55 (0.37–0.74) in Germany. For all countries pooled, intra-specialty agreement was poor for surgeons (0.24, 0.14–0.42) and good for ICPs (0.41, 0.28–0.61). Reading SSI definitions improved agreement among ICPs (0.57) but not surgeons (0.09). Intra-specialty agreement for SSI depth ranged across countries and specialties from 0.05 (0.00–0.10) to 0.50 (0.45–0.55) and was not improved by reading SSI definition. Conclusion Among ICPs and surgeons evaluating case-vignettes of suspected SSI, considerable disagreement occurred regarding the diagnosis, with variations across specialties and countries.

Molecular typing of toxic shock syndrome toxin-1- and Enterotoxin A-producing methicillin-sensitive Staphylococcus aureus isolates from an outbreak in a neonatal intensive care unit.

Outbreaks of Staphylococcus aureus are common in neonatal intensive care units (NICUs). Usually they are documented for methicillin-resistant strains, while reports involving methicillin-susceptible S. aureus (MSSA) strains are rare. In this study we report the epidemiological and molecular investigation of an MSSA outbreak in a NICU among preterm neonates. Infection control measures and interventions were commissioned by the Local Public Health Authority and supported by the Robert Koch Institute. To support epidemiological investigations molecular typing was done by spa-typing and Multilocus sequence typing; the relatedness of collected isolates was further elucidated by DNA SmaI-macrorestriction, microarray analysis and bacterial whole genome sequencing. A total of 213 neonates, 123 healthcare workers and 205 neonate parents were analyzed in the period November 2011 to November 2012. The outbreak strain was characterized as a MSSA spa-type t021, able to produce toxic shock syndrome toxin-1 and Enterotoxin A. We identified seventeen neonates (of which two died from toxic shock syndrome), four healthcare workers and three parents putatively involved in the outbreak. Whole-genome sequencing permitted to exclude unrelated cases from the outbreak and to discuss the role of healthcare workers as a reservoir of S. aureus on the NICU. Genome comparisons also indicated the presence of the respective clone on the ward months before the first colonized/infected neonates were detected.

Nosokomiale Infektionsraten: Messen und Vergleichen

ZusammenfassungDie Surveillance der nosokomialen Infektionen ist inzwischen ein Grundpfeiler der Infektionspräventionsmaßnahmen im Krankenhaus. Ziel des vorliegenden Beitrages ist der Vergleich der Surveillance-Daten zu nosokomialen Infektionen auf Intensivstationen, neonatologischen Intensivstationen und bei operierten Patienten (ITS-KISS, NEO-KISS, OP-KISS) aus dem Krankenhaus-Infektions-Surveillance-System (KISS) mit den korrespondierenden Daten des US-amerikanischen NHSN (National Healthcare Safety Network) und des ECDC (European Centre for Disease Prevention and Control). Insgesamt sind die methodischen Unterschiede zwischen den Surveillance-Systemen eher gering, dennoch gibt es welche. Deshalb müssen die zwischen den Ländern beobachteten Differenzen bei den Infektionsraten sehr sorgfältig interpretiert werden; sie können aus Unterschieden bei der Diagnostik, der Patientenzusammensetzung, bei den medizinischen Interventionen, der Aufenthaltsdauer der Patienten im Krankenhaus, der Auswahl der beteiligten Krankenhäuser, bei der Patientennachverfolgung und der Interpretation der Definitionen resultieren. Auch organisatorische Aspekte wie eine Veröffentlichungspflicht der Infektionsraten können Einfluss haben.AbstractSurveillance of nosocomial infections is meanwhile a cornerstone of infection prevention activities in hospitals. The objective of this article is to compare healthcare-associated infection rates in intensive care patients, neonatal intensive care patients and operated patients (ICU-KISS, OP-KISS, NEO-KISS) of the German nosocomial infection surveillance system (KISS) with the corresponding data of the US American National Healthcare Safety Network (NHSN) and the European Centre for Disease Prevention and Control (ECDC). In general, the methodological differences among the three surveillance systems are minor but there are some exceptions. Therefore, differences between countries have to be interpreted very carefully as they may be due to differences in diagnostics, patient mix, types of interventions, length of stay, selection of participating hospitals, post-discharge surveillance activities and interpretation of case definitions. Organizational aspects, such as mandatory participation with public disclosure on infection rates may also have an impact.Surveillance of nosocomial infections is meanwhile a cornerstone of infection prevention activities in hospitals. The objective of this article is to compare healthcare-associated infection rates in intensive care patients, neonatal intensive care patients and operated patients (ICU-KISS, OP-KISS, NEO-KISS) of the German nosocomial infection surveillance system (KISS) with the corresponding data of the US American National Healthcare Safety Network (NHSN) and the European Centre for Disease Prevention and Control (ECDC). In general, the methodological differences among the three surveillance systems are minor but there are some exceptions. Therefore, differences between countries have to be interpreted very carefully as they may be due to differences in diagnostics, patient mix, types of interventions, length of stay, selection of participating hospitals, post-discharge surveillance activities and interpretation of case definitions. Organizational aspects, such as mandatory participation with public disclosure on infection rates may also have an impact.

[Healthcare-associated infection rates: measuring and comparing. Experiences from the German National Nosocomial Infection Surveillance System (KISS) and from other surveillance systems].

ZusammenfassungDie Surveillance der nosokomialen Infektionen ist inzwischen ein Grundpfeiler der Infektionspräventionsmaßnahmen im Krankenhaus. Ziel des vorliegenden Beitrages ist der Vergleich der Surveillance-Daten zu nosokomialen Infektionen auf Intensivstationen, neonatologischen Intensivstationen und bei operierten Patienten (ITS-KISS, NEO-KISS, OP-KISS) aus dem Krankenhaus-Infektions-Surveillance-System (KISS) mit den korrespondierenden Daten des US-amerikanischen NHSN (National Healthcare Safety Network) und des ECDC (European Centre for Disease Prevention and Control). Insgesamt sind die methodischen Unterschiede zwischen den Surveillance-Systemen eher gering, dennoch gibt es welche. Deshalb müssen die zwischen den Ländern beobachteten Differenzen bei den Infektionsraten sehr sorgfältig interpretiert werden; sie können aus Unterschieden bei der Diagnostik, der Patientenzusammensetzung, bei den medizinischen Interventionen, der Aufenthaltsdauer der Patienten im Krankenhaus, der Auswahl der beteiligten Krankenhäuser, bei der Patientennachverfolgung und der Interpretation der Definitionen resultieren. Auch organisatorische Aspekte wie eine Veröffentlichungspflicht der Infektionsraten können Einfluss haben.AbstractSurveillance of nosocomial infections is meanwhile a cornerstone of infection prevention activities in hospitals. The objective of this article is to compare healthcare-associated infection rates in intensive care patients, neonatal intensive care patients and operated patients (ICU-KISS, OP-KISS, NEO-KISS) of the German nosocomial infection surveillance system (KISS) with the corresponding data of the US American National Healthcare Safety Network (NHSN) and the European Centre for Disease Prevention and Control (ECDC). In general, the methodological differences among the three surveillance systems are minor but there are some exceptions. Therefore, differences between countries have to be interpreted very carefully as they may be due to differences in diagnostics, patient mix, types of interventions, length of stay, selection of participating hospitals, post-discharge surveillance activities and interpretation of case definitions. Organizational aspects, such as mandatory participation with public disclosure on infection rates may also have an impact.Surveillance of nosocomial infections is meanwhile a cornerstone of infection prevention activities in hospitals. The objective of this article is to compare healthcare-associated infection rates in intensive care patients, neonatal intensive care patients and operated patients (ICU-KISS, OP-KISS, NEO-KISS) of the German nosocomial infection surveillance system (KISS) with the corresponding data of the US American National Healthcare Safety Network (NHSN) and the European Centre for Disease Prevention and Control (ECDC). In general, the methodological differences among the three surveillance systems are minor but there are some exceptions. Therefore, differences between countries have to be interpreted very carefully as they may be due to differences in diagnostics, patient mix, types of interventions, length of stay, selection of participating hospitals, post-discharge surveillance activities and interpretation of case definitions. Organizational aspects, such as mandatory participation with public disclosure on infection rates may also have an impact.

Nosokomiale Infektionsraten: Messen und Vergleichen@@@Healthcare-associated infection rates: measuring and comparing: Erfahrungen mit dem Krankenhaus-Infektions-Surveillance-System (KISS) und anderen Surveillance-Systemen@@@Experiences from the German national nosocomial infection surveillance system (KISS) and from other surveillance systems

ZusammenfassungDie Surveillance der nosokomialen Infektionen ist inzwischen ein Grundpfeiler der Infektionspräventionsmaßnahmen im Krankenhaus. Ziel des vorliegenden Beitrages ist der Vergleich der Surveillance-Daten zu nosokomialen Infektionen auf Intensivstationen, neonatologischen Intensivstationen und bei operierten Patienten (ITS-KISS, NEO-KISS, OP-KISS) aus dem Krankenhaus-Infektions-Surveillance-System (KISS) mit den korrespondierenden Daten des US-amerikanischen NHSN (National Healthcare Safety Network) und des ECDC (European Centre for Disease Prevention and Control). Insgesamt sind die methodischen Unterschiede zwischen den Surveillance-Systemen eher gering, dennoch gibt es welche. Deshalb müssen die zwischen den Ländern beobachteten Differenzen bei den Infektionsraten sehr sorgfältig interpretiert werden; sie können aus Unterschieden bei der Diagnostik, der Patientenzusammensetzung, bei den medizinischen Interventionen, der Aufenthaltsdauer der Patienten im Krankenhaus, der Auswahl der beteiligten Krankenhäuser, bei der Patientennachverfolgung und der Interpretation der Definitionen resultieren. Auch organisatorische Aspekte wie eine Veröffentlichungspflicht der Infektionsraten können Einfluss haben.AbstractSurveillance of nosocomial infections is meanwhile a cornerstone of infection prevention activities in hospitals. The objective of this article is to compare healthcare-associated infection rates in intensive care patients, neonatal intensive care patients and operated patients (ICU-KISS, OP-KISS, NEO-KISS) of the German nosocomial infection surveillance system (KISS) with the corresponding data of the US American National Healthcare Safety Network (NHSN) and the European Centre for Disease Prevention and Control (ECDC). In general, the methodological differences among the three surveillance systems are minor but there are some exceptions. Therefore, differences between countries have to be interpreted very carefully as they may be due to differences in diagnostics, patient mix, types of interventions, length of stay, selection of participating hospitals, post-discharge surveillance activities and interpretation of case definitions. Organizational aspects, such as mandatory participation with public disclosure on infection rates may also have an impact.Surveillance of nosocomial infections is meanwhile a cornerstone of infection prevention activities in hospitals. The objective of this article is to compare healthcare-associated infection rates in intensive care patients, neonatal intensive care patients and operated patients (ICU-KISS, OP-KISS, NEO-KISS) of the German nosocomial infection surveillance system (KISS) with the corresponding data of the US American National Healthcare Safety Network (NHSN) and the European Centre for Disease Prevention and Control (ECDC). In general, the methodological differences among the three surveillance systems are minor but there are some exceptions. Therefore, differences between countries have to be interpreted very carefully as they may be due to differences in diagnostics, patient mix, types of interventions, length of stay, selection of participating hospitals, post-discharge surveillance activities and interpretation of case definitions. Organizational aspects, such as mandatory participation with public disclosure on infection rates may also have an impact.