Rationale, design and conduct of a randomised controlled trial evaluating a primary care-based complex intervention to improve the quality of life of heart failure patients: HICMan (Heidelberg Integrated Case Management) : study protocol

Background: Chronic congestive heart failure (CHF) is a complex disease with rising prevalence, compromised quality of life (QoL), unplanned hospital admissions, high mortality and therefore high burden of illness. The delivery of care for these patients has been criticized and new strategies addressing crucial domains of care have been shown to be effective on patients' health outcomes, although these trials were conducted in secondary care or in highly organised Health Maintenance Organisations. It remains unclear whether a comprehensive primary care-based case management for the treating general practitioner (GP) can improve patients' QoL. Methods/Design: HICMan is a randomised controlled trial with patients as the unit of randomisation. Aim is to evaluate a structured, standardized and comprehensive complex intervention for patients with CHF in a 12-months follow-up trial. Patients from intervention group receive specific patient leaflets and documentation booklets as well as regular monitoring and screening by a prior trained practice nurse, who gives feedback to the GP upon urgency. Monitoring and screening address aspects of disease-specific selfmanagement, (non)pharmacological adherence and psychosomatic and geriatric comorbidity. GPs are invited to provide a tailored structured counselling 4 times during the trial and receive an additional feedback on pharmacotherapy relevant to prognosis (data of baseline documentation). Patients from control group receive usual care by their GPs, who were introduced to guidelineoriented management and a tailored health counselling concept. Main outcome measurement for patients' QoL is the scale physical functioning of the SF-36 health questionnaire in a 12-month follow-up. Secondary outcomes are the disease specific QoL measured by the Kansas City Cardiomyopathy questionnaire (KCCQ), depression and anxiety disorders (PHQ-9, GAD-7), adherence (EHFScBS and SANA), quality of care measured by an adapted version of the Patient Chronic Illness Assessment of Care questionnaire (PACIC) and NTproBNP. In addition, comprehensive clinical data are collected about health status, comorbidity, medication and health care utilisation. Discussion: As the targeted patient group is mostly cared for and treated by GPs, a comprehensive primary care-based guideline implementation including somatic, psychosomatic and organisational aspects of the delivery of care (HICMAn) is a promising intervention applying proven strategies for optimal care. Trial registration: Current Controlled Trials ISRCTN30822978

Delegation of GP-home visits to qualified practice assistants: assessment of economic effects in an ambulatory healthcare centre

<p>Abstract</p> <p>Background</p> <p>Against the background of a decreasing number of general practitioners (GPs) in rural regions in Germany, the AGnES-concept (AGnES = GP-supporting, community-based, e-health-assisted, systemic intervention) supports the delegation of regular GP-home visits to qualified practice assistants. The concept was implemented and evaluated in different model projects in Germany.</p> <p>To explore the economic effects of this concept, the development of the number of home visits in an ambulatory healthcare centre was analysed and compared with the number of home visits in the surrounding county.</p> <p>Methods</p> <p>Information about GP-home visits was derived from reimbursement data of the ambulatory healthcare centre and a statutory health insurance. Information about home visits conducted by AGnES-practice assistants was collected from the project documentation over a time period of 12 consecutive quarter years, four quarter years before the beginning of the project and 8 quarter years while the project was implemented, considering background temporal trends on the population level in the study region.</p> <p>Results</p> <p>Within the ambulatory healthcare centre, the home visits by the GPs significantly decreased, especially the number of medically urgent home visits. However, the overall rate of home visits (conducted by the GPs and the AGnES-practice assistants together) did not change significantly after implementation of the AGnES-concept. In the surrounding county, the home visit rates of the GPs were continuous; the temporal patterns were approximately equal for both usual and urgent home visits.</p> <p>Conclusion</p> <p>The results of the analyses show that the support by AGnES-practice assistants led to a decrease of GP-home visits rather than an induction of additional home visits by the AGnES-practice assistants. The most extended effect is related to the medically urgent home visits rather than to the usual home visits.</p

Influence of Nonlinear Multiaxial Matrix Viscoelasticity on Piezoresistivity of Carbon Nanotube Polymer Composites

Nanocomposites are prominent candidates to extend the capabilities in areas of established fiber reinforced composites. Carbon nanotubes (CNT) with their outstanding mechanical, electrical, and thermal properties are of particular interest. Especially polymers profit from the addition of CNTs, and can be rendered significantly stiffer, stronger, and even electrically conductive. The resulting electrical conductance is deformation-sensitive, known as piezoresistivity, and is utilized in strain sensing applications. However, the polymer matrix introduces time- and temperature-dependency into the mechanical behavior, known as viscoelasticity, and thus affects the relationship between deformation and electrical conductivity over time. Although piezoresistivity and polymer viscoelasticity have been studied separately, the interaction of both phenomena is not well understood. This thesis presents a combination of numerical, experimental, and analytical investigations of the behavior of viscoelastic, piezoresistive nanocomposites. The major goal of this research is to elucidate the underlying mechanism of viscoelasticity on strain sensing via piezoresistivity, without relying on the ill-defined viscoelastic Poisson\u27s ratio. In the study of piezoresistive nanocomposites, a statistical, three-dimensional representative volume element is created first via the finite element method, and validated through fundamental quantities, such as total conductance and elastic piezoresistivity, against experimental data from literature. A novel electron tunneling model is proposed, incorporating the chirality of individual CNTs with regard to the local alignment between CNTs. The change of tunneling resistance via mere reorientation of the CNTs is identified as another source of bulk resistance change under deformation and lead to an increase in the previously underestimated numerical strain-sensitivity. The multiaxial viscoelasticity is characterized via uniaxial creep tests at elevated temperatures, simultaneous measurement of axial and transverse strain, and the time-temperature superposition principle. A non-constant electrical resistance is observed numerically during stress relaxation at constant axial strain. The loss of sensing repeatability is shown in a cyclic numerical simulation

Microbial Ingrowth Around Single- and Multi-Component Adhesives Studied in vitro

The aim of this study was to compare the in vitro microbial leakage in 4 micro-hybrid composites in combination with 4 single-component dental adhesives (Scotchbond 1/Z100 MP = group 1; Syntac Single-Component/Tetric Flow = group 3; OptiBond Solo/XRV Herculite = group 5; Solobond M/Arabesk Top = group 7) and 4 multi-component dental adhesives (Scotchbond Multi-Purpose/Z100 MP = group 2; Syntac/Tetric Flow = group 4; OptiBond FL/XRV Herculite = group 6; Solobond Plus/Arabesk Top = group 8). Ninety-four mixed standardized Class V cavities of human caries-free extracted premolars were filled with eight different composite adhesive systems using a one-layer (groups 1–4) or a two-layer technique (groups 5–8). After thermocycling and incubation in a broth culture of Streptococcus mutans and Lactobacillus acidophilus, followed by decalcification and staining, the extent and the type of microbial leakage were measured histologically. The extent of microbial leakage in the composite restorations was very low in all groups and there were no significant differences between adhesives. Z100 MP in combination with single- and multi-component adhesives showed a significantly higher microbial leakage than Tetric Flow systems (U test: p = 0.037). XRV Herculite adhesive systems showed significantly less extensive microbial leakage than Arabesk Top adhesive systems (U test: p < 0.001). The single-component dental adhesives achieved a marginal adaptation of composites comparable to that of multi-component adhesives in vitro.Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich

Primary care-based multifaceted, interdisciplinary medical educational intervention for patients with systolic heart failure: lessons learned from a cluster randomised controlled trial

Abstract Background Chronic (systolic) heart failure (CHF) is a common and disabling condition. Adherence to evidence-based guidelines in primary care has been shown to improve health outcomes. The aim was to explore the impact of a multidisciplinary educational intervention for general practitioners (GPs) (Train the trainer = TTT) on patient and performance outcomes. Methods This paper presents the key findings from the trial and discusses the lessons learned during the implementation of the TTT trial. Primary care practices were randomly assigned to the TTT intervention or to the control group. 37 GPs (18 TTT, 19 control) were randomised and 168 patients diagnosed with ascertained CHF (91 TTT, 77 control) were enrolled. GPs in the intervention group attended four meetings addressing clinical practice guidelines and pharmacotherapy feedback. The primary outcome was patient self-reported quality of life at seven months, using the SF-36 Physical Functioning scale. Secondary outcomes included other SF-36 scales, the Kansas City Cardiomyopathy Questionnaire (KCCQ), total mortality, heart failure hospital admissions, prescribing, depressive disorders (PHQ-9), behavioural change (European Heart Failure Self-Care Behaviour Scale), patient-perceived quality of care (EUROPEP) and improvement of heart failure using NT-proBNP-levels. Because recruitment targets were not achieved an exploratory analysis was conducted. Results There was high baseline achievement in both groups for many outcomes. At seven months, there were no significant mean difference between groups for the primary outcome measure (-3.3, 95%CI -9.7 to 3.1, p = 0.30). The only difference in secondary outcomes related to the prescribing of aldosterone antagonists by GPs in the intervention group, with significant between group differences at follow-up (42 vs. 24%, adjusted OR = 4.0, 95%CI 1.2–13; p = 0.02). Conclusion The intervention did not change the primary outcome or most secondary outcomes. Recruitment targets were not achieved and the under-recruitment of practices and patients alongside a selection bias of participating GPs, prohibit definite conclusions, but the CI indicates a non-effectiveness of the intervention in this sample. We describe the lessons learned from conducting the trial for the future planning and conduct of confirmatory trials in primary care. Trial registration ISRCTN08601529.</p

Acid Production by Oral Strains of Candida albicans and Lactobacilli

Both Candida albicans and lactobacilli are common colonizers of carious lesions in children and adolescents. The purpose of this study is to compare the velocity of acid production between C. albicans and several Lactobacillus species at different pH levels and concentrations of glucose. Washed, pure resting-cell suspensions were obtained by culturing a total of 28 oral isolates comprising the species C. albicans, Lactobacillus rhamnosus, Lactobacillus paracasei paracasei, Lactobacillus paracasei tolerans and Lactobacillus delbrueckii lactis. Acid production from glucose was determined at a constant pH of 7.0, 5.5, 5.0 and 4.0 by repeated titrations with NaOH in an automated pH-stat system. Acid formation rates of yeast and lactobacilli proved to be similar at both neutral and low pH, while in a moderately acidic environment C. albicans produced less acid than the lactobacilli. Ion chromatographic analysis of the cell-free medium after titration revealed pyruvate to be the predominant organic acid anion secreted by C. albicans. The proportion of organic acids to overall acid production by the yeast was below 10% at neutral conditions, in contrast to 42–66% at pH 4.0. Compared to lactobacilli, yeast required a concentration of glucose that was about 50 times higher to allow acid production at half the maximum speed. Considering the clinical data in the literature about the frequency and proportions of microorganisms present in early childhood caries lesions, the contribution of oral lactobacilli as well as C. albicans to overall microbial acid formation appears to be important.Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich

Barrieren der Leitlinienumsetzung und Fortbildungsbedarf von Hausärzten zur Herzinsuffizienz: eine qualitative Studie [Barriers to guideline implementation and educational needs of general practitioners regarding heart failure: a qualitative study]

[english] Objectives: A clinical practice guideline (CPG) contains specifically developed recommendations that can serve physicians as a decision aid in evidence-based practice. The implementation of heart failure (HF) CPGs represents a challenge in general practice. As part of the development of a tailored curriculum, aim of this study was to identify barriers of guideline adherence and needs for medical education (CME) in HF care.Methods: We conducted a modified focus group with elements of a workshop of three hours duration. Thirteen GPs collected and discussed together and parallel in smaller groups barriers of guideline implementation. Afterwards they performed a needs assessment for a tailored CME curriculum for chronic HF. The content of the discussions was analysed qualitatively according to Mayring and categorised thematically.Results: Barriers of guideline adherence were found in the following areas: doctor: procedural knowledge (knowledge gaps), communicative and organisational skills (e.g. time management) and attitude (dissatisfaction with time-money-relation). Patients: individual case-related problems (multimorbidity, psychiatric comorbidity, expectations and beliefs). Doctor and patient: Adherence and barriers of communication. Main measures for improvement of care concerned the areas of the identified barriers of guideline adherence with the focus on application-oriented training of the abovementioned procedural knowledge and skills, but also the supply of tools (like patient information leaflets) and patient education. Conclusion: For a CME-curriculum for HF tailored to the needs of GPs, a comprehensive educational approach seems necessary. It should be broad-based and include elements of knowledge and skills to be addressed and trained case-related. Additional elements should include support in the implementation of organisational processes in the practice and patient education.<br>[german] Zielsetzung: Leitlinien zur Herzinsuffizienz (HI) enthalten systematisch entwickelte Empfehlungen, deren Umsetzung speziell in der hausärztlichen Praxis eine bekannte Herausforderung darstellt. Ziel der vorliegenden Studie war es, Barrieren bei der Umsetzung der Leitlinienempfehlungen zu identifizieren, Vorschläge zu Verbesserungsmaßnahmen der hausärztlichen Versorgung und für die Entwicklung einer bedarfsgerechten Fortbildung zu gewinnen.Methodik: Es wurde eine modifizierte Fokusgruppe mit Workshopcharakter durchgeführt. In drei parallelen Kleingruppen erarbeiteten 13 Hausärzte Barrieren bei der Leitlinienumsetzung zur HI. Darauf aufbauend wurde eine Bedarfsanalyse bzgl. der Lernziele und der spezifischen Verbesserungsmaßnahmen für eine hausärztliche Fortbildung zur HI durchgeführt. Die protokollierten Aussagen der Ärzte wurden mittels Inhaltsanalyse nach Mayring ausgewertet und anschließend thematisch kategorisiert.Ergebnisse: Als Barrieren der Umsetzung vorhandener Leitlinien nannten die teilnehmenden Ärzte arztseitige Defizite und Unterstützungsbedarf in den Dimensionen Wissen, kommunikativen und organisatorischen Fähigkeiten (z. B. Zeitmangel/-management) und der Haltung gegenüber Leitlinien (z.B. Faulheit). Den Patienten wurden individuelle, patientenbezogene Probleme (z.B. Komplexität des Einzelfalles bei Multimorbidität, psychische Komorbidität) sowie ablehnende Einstellungen (z.B. gegenüber „Schulmedizin“) zugeschrieben. Im Bereich der Arzt-Patient-Interaktion wurden u.a. mangelnde medikamentöse Adhärenz und Kommunikationsprobleme als Barrieren genannt. Vorschläge zu Verbesserungs- bzw. Schulungsmaßnahmen umfassten breit angelegte Schulungskonzepte (z.B. in interdisziplinären Qualitätszirkeln mit Fall-Audit), die neben der Vermittlung von Wissensaspekten aus einer (idealerweise einheitlichen) Leitlinie auch praktische Fertigkeiten hinsichtlich Arzt-Patienten-Kommunikation und Praxis-Organisation einschlossen. Die Bereitstellung praktikabler Arbeitsmaterialien und Patientenschulungen sollten aus Sicht der Teilnehmer die Arztschulungen ergänzen.Schlussfolgerung: Ein Fortbildungs-Curriculum für Hausärzte zur HI scheint einer umfassenden Leitlinienschulung zu bedürfen, in welchen insbesondere Handlungskompetenz und kommunikative Fertigkeiten anwendungsorientiert geübt werden sollten. Weitere Bestandteile sollten Hilfestellungen zur Implementierung von Organisationsabläufen und Patientenschulungen sein