Stratification of cumulative antibiograms in hospitals for hospital unit, specimen type, isolate sequence and duration of hospital stay

Background Empirical antibiotic therapy is based on patients' characteristics and antimicrobial susceptibility data. Hospital-wide cumulative antibiograms may not sufficiently support informed decision-making for optimal treatment of hospitalized patients. Methods We studied different approaches to analysing antimicrobial susceptibility rates (SRs) of all diagnostic bacterial isolates collected from patients hospitalized between July 2005 and June 2007 at the University Hospital in Zurich, Switzerland. We compared stratification for unit-specific, specimen type-specific (blood, urinary, respiratory versus all specimens) and isolate sequence-specific (first, follow-up versus all isolates) data with hospital-wide cumulative antibiograms, and studied changes of mean SR during the course of hospitalization. Results A total of 16 281 isolates (7965 first, 1201 follow-up and 7115 repeat isolates) were tested. We found relevant differences in SRs across different hospital departments. Mean SRs of Escherichia coli to ciprofloxacin ranged between 64.5% and 95.1% in various departments, and mean SRs of Pseudomonas aeruginosa to imipenem and meropenem ranged from 54.2% to 100% and 80.4% to 100%, respectively. Compared with hospital cumulative antibiograms, lower SRs were observed in intensive care unit specimens, follow-up isolates and isolates causing nosocomial infections (except for Staphylococcus aureus). Decreasing SRs were observed in first isolates of coagulase-negative staphylococci with increasing interval between hospital admission and specimen collection. Isolates from different anatomical sites showed variations in SRs. Conclusions We recommend the reporting of unit-specific rather than hospital-wide cumulative antibiograms. Decreasing antimicrobial susceptibility during hospitalization and variations in SRs in isolates from different anatomical sites should be taken into account when selecting empirical antibiotic treatmen

Correlation between case mix index and antibiotic use in hospitals

Background To compare the quantitative antibiotic use between hospitals or hospital units and to explore differences, adjustment for severity of illness of hospitalized patients is essential. The case mix index (CMI) is an economic surrogate marker (i.e. the total cost weights of all inpatients per a defined time period divided by the number of admissions) to describe the average patients' morbidity of individual hospitals. We aimed to investigate the correlation between CMI and hospital antibiotic use. Methods We used weighted linear regression analysis to evaluate the correlation between in-hospital antibiotic use in 2006 and CMI of 18 departments of the tertiary care University Hospital Zurich and of 10 primary and 2 secondary acute care hospitals in the Canton of Zurich in Switzerland. Results Antibiotic use varied substantially between different departments of the university hospital [defined daily doses (DDD)/100 bed-days, 68.04; range, 20.97-323.37] and between primary and secondary care hospitals (range of DDD/100 bed-days, 15.45-57.05). Antibiotic use of university hospital departments and the different hospitals, respectively, correlated with CMI when calculated in DDD/100 bed-days [coefficient of determination (R2), 0.57 (P = 0.0002) and 0.46 (P = 0.0065)], as well as when calculated in DDD/100 admissions [R2, 0.48 (P = 0.0008) and 0.85 (P < 0.0001), respectively]. Conclusions Antibiotic use correlated with CMI across various specialties of a university hospital and across different acute care hospitals. For benchmarking antibiotic use within and across hospitals, adjustment for CMI may be a useful tool in order to take into account the differences in hospital category and patients' morbiditie

Phänomene der Wahrnehmungs-Handlungs-Kopplung im Sportspiel – Eine Untersuchung zur Aufmerksamkeitssteuerung anhand von Blickbewegungen.

Essig K, Weigelt M, Berger A, Thieschaefer L, Schack T. Phänomene der Wahrnehmungs-Handlungs-Kopplung im Sportspiel – Eine Untersuchung zur Aufmerksamkeitssteuerung anhand von Blickbewegungen. In: Krüger M, Neuber N, Brach M, Reinhart K, eds. 19. Sportwissenschaftlicher Hochschultag der Deutschen Vereinigung für Sportwissenschaft in Münster: Vol. 191. Bildungspotenziale im Sport. Hamburg: Czwalina; 2009: 176

Properties of gas-atomized Cu-Ti-based metallic glass powders for additive manufacturing

Laser powder bed fusion (PBF-LB/M) of bulk metallic glasses permits large and complex components tosolidify to an amorphous state, thus expanding the processing possibilities of this material class. Here, theCu-Ti-Zr-Ni family, also known as Vitreloy 101, is systematically investigated for processing of the PBFLB/M powder itself. Gas atomization was used to produce powder of Vit101 and derivates micro-alloyedwith Si and Sn. The influence of atomization and alloy composition on glass formation, oxygen content,particle morphology, and flowability were investigated. Amorphous powder was successfully obtainedusing industrial-grade purity as feedstock for the atomization. The oxygen content within the powderwas controlled by the surface-to-volume ratio, without significant influence of the different atomizationparameters and the microalloying itself. The powder displayed high circularity with sufficient flowability after drying. Our results contribute to the investigation of Vitreloy 101 alloys as promising candidates forPBF-LB/M application