Model to evaluate the impact of hospital-based interventions targeting false-positive blood cultures on economic and clinical outcomes.

BACKGROUND: Blood culture contamination (BCC) increases length of stay (LOS) and leads to unnecessary antimicrobial therapy and/or hospital-acquired conditions (HACs). AIM: To quantify the magnitude of additional LOS, costs to hospitals and society, and harm to patients attributable to BCC. METHODS: A retrospective matched survival analysis was performed involving hospitalized patients with septicaemia-compatible symptoms. BCC costs, HACs and potential savings were calculated based on the primary LOS data, a modified Delphi process and published sources. The cost analysis compared standard care with interventions for reducing BCC, and estimated annual economic and clinical consequences for a typical hospital and for the USA as a whole. FINDINGS: Patients with BCC experienced a mean increase in LOS of 2.35 days (P=0.0076). Avoiding BCC would decrease costs by $6463 [$4818 from inpatient care (53% of which was from reduced LOS) and 26% from reduced antibiotic use]. Annually, in a typical 250- to 400-bed hospital, employing phlebotomists would save $1.3 million and prevent 24 HACs (including two cases of Clostridium difficile infection); based on clinical efficacy evidence, use of the studied initial specimen diversion device (ISDD) would save $1.9 million and prevent 34 HACs (including three cases of C. difficile infection). In the USA, the respective strategies would prevent 69,300 and 102,900 HACs (including 6000 and 8900 cases of C. difficile infection) and save $5 and $7.5 billion. CONCLUSION: Costs and clinical burdens associated with false-positive cultures are substantial and can be reduced by available interventions, including phlebotomists and use of ISDD.

Leadership in health care: developing a post-merger strategy for Europe's largest university hospital.

PURPOSE: This paper's aim is to identify existing and developing new concepts of organization, management, and leadership at a large European university hospital; and to evaluate whether mixed qualitative-quantitative methods with both internal and external input can provide helpful views of the possible future of large health care providers. DESIGN/METHODOLOGY/APPROACH: Using the Delphi method in semi-structured, semi-quantitative interviews, with managers and employees as experts, the authors performed a vertical and a horizontal internal analysis. In addition, input from innovative faculties in other countries was obtained through structured power questions. These two sources were used to create three final scenarios, which evaluated using traditional strategic planning methods. FINDINGS: There is found a collaboration scenario in which faculty and hospital are separated; a split scenario which divides the organization into three independent hospitals; and a corporation scenario in which corporate activities are bundled in three separate entities. PRACTICAL IMPLICATIONS: In complex mergers of knowledge-driven organizations, the employees of the own organization (in addition to external consultants) might be tapped as a knowledge resource to successful future business models. ORIGINALITY/VALUE: The paper uses a real world consulting case to present a new set of methods for strategic planning in large health care provider organizations.

[Visual rating of T2'-blood-oxygen-level-dependent magnetic resonance imaging in acute stroke patients--a pilot study]. / T2'-Blood-Oxygen-Level-Dependent-Magnetresonanz-Bildgebung beim akuten Schlaganfall--eine Pilotstudie.

PURPOSE: Delineation of brain tissue that is at risk but not yet infarcted (penumbra) continues to be a major challenge for stroke imaging. Metabolic characterization of the penumbra might be able to be achieved using blood-oxygen-level-dependent (BOLD) imaging. MATERIALS AND METHODS: We analyzed MRI data from 20 patients within the first 6 hours after stroke onset and after 5-8 days. Among other sequences, the MRI protocol consisted of diffusion-weighted (DWI/ADC = apparent diffusion coefficient) and quantitative T2 and T2* imaging (qT2, qT2*). BOLD images (T2') were calculated using 1/T2' = 1/qT2* - 1/qT2. BOLD lesions were rated by two blinded observers. RESULTS: Based on the primary blinded reading of the BOLD images, the lesion side was rated correctly by observers 1 and 2 in 80/50 % of the cases, incorrectly in 5/40 % of the cases, and rated as not visible in 15/10 % of the cases. After unblinding the observers, the visibility was rated in 45/45 % of the cases as good, in 35/40 % of the cases as reasonable, and in 20/15 % of the cases as insufficient for diagnostic purposes. The sensitivity for subsequent infarct growth was 0.88 (95 % confidence interval, CI 0.47 to 0.99), the specificity was 0.33 (95 % CI 0.07 to 0.70), the positive predictive value (PPV) was 0.54 (95 % CI 0.25 to 0.81), and the negative predictive value (NPV) was 0.75 (95 % CI 0.19 to 0.99). The odds ratio for subsequent infarct growth was 3.5 (95 % CI 0.20 to 115.53). CONCLUSION: Hypo-intense lesions in BOLD imaging were visible and exceeded the lesion in diffusion-weighted imaging in most of the stroke patients. The encouraging results justify further testing of the hypothesis that BOLD lesions, when larger than DWI lesions, are associated with infarct growth from initial DWI to final infarct.

Improvement of DNA-visualization in dynamic mode atomic force microscopy in air.

Near-contact mode atomic force microscopy (AFM) imaging leads to sharper representations of DNA double strands on mica imaged at ambient conditions compared with noncontact mode AFM. Phase shift was used for feedback control yielding height information using a simple model calculation. No contact between tip and sample occurs. Measured DNA widths were up to four times smaller than measured with the same AFM tip in noncontact mode at ambient condition.

Nanodissection and noncontact imaging of plasmid DNA with an atomic force microscope.

In this paper we report that a combination of noncontact and contact atomic force microscopy is a convenient and reliable method for imaging and dissecting single plasmid deoxyribonucleic acid (DNA) strands on mica at ambient conditions without leaving feedback and without damage to the scanning tips. The width and thickness measured at different points of the DNA strands agree with literature data and are the same before and after dissection.

Intraepidemic variants of influenza virus H3 hemagglutinin differing in the number of carbohydrate side chains.

During the epidemic outbreak in the region of Greifswald in the winter 1974/75, we found influenza virus variants which showed differences in the electrophoretic mobility of HA. Among the 25 isolates 13 were of slower and 12 of higher mobility. HA1 of 6 isolates was studied by determining the number of the carbohydrate side chains and by direct sequencing of vRNA. Evidence is presented that variants showing a slower electrophoretic mobility of HA1 had consistently acquired a seventh carbohydrate side chain at Asn 126 in epitope A. All the isolates differed from the reference strain A/Port Chalmers/1/73 by the loss of the oligosaccharide at Asn 81. The field strain A/Dresden/3/71 possessed only 5 oligosaccharides in HA1. These results suggest that changes in glycosylation are an important mechanism in the structural variation underlying antigenic drift of HA.

[Variations in the NP protein of the influenza virus detected by peptide mapping and polyacrylamide gel electrophoresis]. / Variatsii belka NP virusa grippa, vyiavliaemye posredstvom peptidnogo kartirovaniia i élektroforeza v poliakrilamidnom gele.

NP proteins of 19 reference and 42 epidemic strains of influenza A virus were analysed for their mobility in polyacrylamide gel electrophoresis and distribution of tryptic peptides. The strains could be divided into 4 groups by differences in their electrophoretic mobility, and into 9 groups according to reproducible differences of several hydrophilic peptides determined by peptide mapping.

Variation of influenza A (H3N2) viruses isolated in the G.D.R. during 1969-1980 epidemics.

A collection of 39 influenza A virus strains of the subtype H3N2 isolated in G.D.R. and of six reference strains were analysed with regard to the antigenic structure of their surface proteins haemagglutinin (HA) and neuraminidase (NA) as well as regarding their polypeptide variations. For the field strains during the drift period from spring 1969 to spring 1980 seven main variations resulted from eight polyclonal sera with the haemagglutination inhibition test, and five main variations from six polyclonal sera with the neuraminidase inhibition test. Using the polyacrylamide gel electrophoresis polypeptide variations in HA, nonstructural proteins NS1, NS2 and nucleoprotein (NP) were detected. It could be shown that, even during one epidemic, strains circulated with different polypeptide composition. With the help of peptide mapping further variations of NP and NS1 were registered. The mechanisms leading to the emergence of new epidemic strains are discussed.

Differences of nucleoproteins of human and avian influenza A virus strains shown by polyacrylamide gel electrophoresis and by the peptide mapping technique.

Electrophoretic mobility differences in polyacrylamide gels were detected between (35S)-methionine-labelled nucleoproteins (NPs) induced in monolayer cells by 15 human and 4 avian reference strains of influenza viruses. The (35S)-methionine-labelled tryptic peptides of nucleoproteins of these strains were also analyzed by peptide mapping technique. Based on several detectable hydrophilic peptides the NPs could be arranged in 7 clearly differentiable groups. After radioiodination of NPs from 4 human and 3 avian reference strains the tryptic peptide patterns showed one clear difference between human and avian strains.