A comparison between local wave speed in the carotid and femoral arteries in healthy humans: application of a new method

The wave speed (c) and the arrival time of reflected wave (Trw) in the common left carotid artery and common left femoral artery have been evaluated in 70 healthy subjects, aged 35-55 years with a non-invasive method. Wave speed and the arrival time of reflected waves were determined with InDU-loop and non-invasive wave intensity analysis (ndl) techniques, respectively. Diameter (D) was measured with ultrasound echo wall tracking and velocity (U) was obtained by ultrasonography. A statistical analysis has been carried out in order to establish a potential relation of c and Trw with gender and age in the study population. Subjects have been divided in two classes of age, one from 35 to 45 years and the other from 45 to 55 years. Results show that c and Trw in the femoral artery are higher than those in carotid, in both men and women (P < 0.001). Also, the distance of the reflection (L) site from the point of measurement is higher in the femoral than in the carotid artery. We did not find statistically significant differences between c, age or gender in femoral artery. However, c in the carotid artery increases with age (P < 0.05), but did not change between men and women. In this paper InDU-loop has been used for the first time to determine c and Trw in carotid and femoral arteries in a large population of healthy subjects

Different effects of tocolytic medication on blood pressure and blood pressure amplification

Background The importance of tocolysis has been discussed extensively. Beta-2 adrenoceptor agonistic drugs like ritodrine have been the reference tocolytic drugs in most countries. Cardiovascular side-effects are frequent. Atosiban, a newer tocolytic drug, is a competitive antagonist of oxytocin and has fewer cardiovascular side effects. Although large studies exist, there is mainly subjective reporting of adverse reactions with a focus on blood pressure data. Objectives Evaluation of the acute effects of therapeutic doses of ritodrine and atosiban in comparison to placebo on central and peripheral blood pressures, central-to-peripheral blood pressure amplification and the augmentation index (AIx) in healthy non-pregnant female volunteers. Methods A double-blind, randomized, crossover trial was carried out in 20 healthy non-pregnant female volunteers. Hemodynamic measurements were performed under standardized conditions. Results At steady state, central and peripheral pressures did not differ from placebo in the atosiban group. During ritodrine-infusion, central SBP increased by 11% versus placebo (p = 0.012) and peripheral SBP by 10% (p = 0.004). In contrast to atosiban and placebo, blood pressure amplification was absent in the ritodrine group. While the AIx did not change in the atosiban group, with ritodrine, the AIx tended to decrease. Conclusions The present study shows the significant effects of ritodrine on the cardiovascular system. Atosiban has no significant effects and may be an appropriate alternative to tocolyticum, particularly in cardiovascularly complicated pregnancies

Impact Evaluation in Practice

The book is a comprehensive and accessible introduction to impact evaluation for policy makers and development practitioners. First published in 2011, it has been used widely across the development and academic communities. The book incorporates real-world examples to present practical guidelines for designing and implementing impact evaluations. Readers will gain an understanding of impact evaluations and the best ways to use them to design evidence-based policies and programs. The updated version covers the newest techniques for evaluating programs and includes state-of-the-art implementation advice, as well as an expanded set of examples and case studies that draw on recent development challenges. It also includes new material on research ethics and partnerships to conduct impact evaluation. The handbook is divided into four sections: Part One discusses what to evaluate and why; Part Two presents the main impact evaluation methods; Part Three addresses how to manage impact evaluations; Part Four reviews impact evaluation sampling and data collection. Case studies illustrate different applications of impact evaluations. The book links to complementary instructional material available online, including an applied case as well as questions and answers. The updated second edition will be a valuable resource for the international development community, universities, and policy makers looking to build better evidence around what works in development

Prevalence and management of antibiotic associated diarrhea in general hospitals

Background: Antibiotic-associated diarrhea (AAD) is a common adverse effect of antibiotic (AB) treatment. This study aimed to measure the overall prevalence of AAD (including mild to moderate diarrhea) in hospitalized AB treated patients, to investigate associated risk factors and to document AAD associated diagnostic investigations, contamination control and treatment. Methods: During 8 observation days (with time delay of 10-14 days between each observation day), all adult patients hospitalized at an internal medicine ward of 4 Belgian participating hospitals were screened for AB use. Patients receiving AB on the observation day were included in the study and screened for signs and symptoms of AAD using a period prevalence methodology. Clinical data were collected for all AB users and AAD related investigations and treatment were collected for the entire duration of AAD. Additionally, nurses noted daily the frequency of all extra care associated to the treatment of the diarrhea. Results: A total of 2543 hospitalized patients were screened of which 743 were treated with AB (29.2%). Included AB users had a mean age of 68 yr (range 16-99) and 52% were male. Penicillins were mostly used (63%) and 19% received more than one AB. AAD was observed in 9.6% of AB users including 4 with confirmed Clostridium difficile infection. AAD started between 1 and 16 days after AB start (median 5) and had a duration of 2 to 41 days (median 4). AAD was significantly associated with higher age and the use of double AB and proton pump inhibitors. AAD patients had extra laboratory investigations (79%), received extra pharmacological treatment (42%) and 10 of them were isolated (14%). AAD related extra nursing time amounted to 51 minutes per day for the treatment of diarrhea. Conclusions: In this observational study, with one third of hospitalized patients receiving AB, an AAD period prevalence of 9.6% in AB users was found. AAD caused extra investigations and treatment and an estimated extra nursing care of almost one hour per day. Preventive action are highly recommended to reduce the prevalence of AAD and associated health care costs

Health and budget impact of combined HIV prevention : first results of the BELHIVPREV model

Objectives: We developed a pragmatic modelling approach to estimate the impact of treatment as prevention (TasP); outreach testing strategies; and pre-exposure prophylaxis (PrEP) on the epidemiology of HIV and its associated pharmaceutical expenses. Methods: Our model estimates the incremental health (in terms of new HIV diagnoses) and budget impact of two prevention scenarios (outreach+TasP and outreach+TasP+PrEP) against a 'no additional prevention' scenario. Model parameters were estimated from reported Belgian epidemiology and literature data. The analysis was performed from a healthcare payer perspective with a 15-year-time horizon. It considers subpopulation differences, HIV infections diagnosed in Belgium having occurred prior to migration, and the effects of an ageing HIV population. Results: Without additional prevention measures, the annual number of new HIV diagnoses rises to over 1350 new diagnoses in 2030 as compared to baseline, resulting in a budget expenditure of (sic)260.5 million. Implementation of outreach+TasP and outreach+TasP+PrEP results in a decrease in the number of new HIV diagnoses to 865 and 663 per year, respectively. Respective budget impacts decrease by (sic)20.6 million and (sic)33.7 million. Conclusion: Foregoing additional investments in prevention is not an option. An approach combining TasP, outreach and PrEP is most effective in reducing the number of new HIV diagnoses and the HIV treatment budget. Our model is the first pragmatic HIV model in Belgium estimating the consequences of a combined preventive approach on the HIV epidemiology and its economic burden assuming other prevention efforts such as condom use and harm reduction strategies remain the same

La evaluación de impacto en la práctica

La segunda edición del libro "Evaluación de impacto en la práctica" es una introducción completa y accesible a las evaluaciones del impacto para la comunidad internacional de desarrollo, universidades, y los formuladores de políticas públicas que buscan contar con una mejor evidencia en torno a lo que funciona en el desarrollo. La versión actualizada abarca las técnicas más recientes para evaluar programas e incluye consejos de implementación de última generación, así como un conjunto ampliado de ejemplos y estudios de casos que se basan en recientes intervenciones de desarrollo. También incluye nuevos materiales sobre la ética de la investigación y alianzas para llevar a cabo evaluaciones de impacto. A lo largo del libro, los estudios de casos ilustran aplicaciones de las evaluaciones de impacto. La publicación incluye enlaces de material didáctico complementario disponible en línea

Applied arterial mechanics: from theory to clinical practice

Cardiovascular disease remains to date the number one cause of death in the Western World. The early detection of subjects at increased cardiovascular risk and the first stages of cardiovascular disease thus remain a spearhead in clinical research. Increasingly this research integrates an engineering approach for the development of new diagnostic tools for use in clinical practice. This thesis therefore focuses on large artery mechanics. An abnormal thickening of the arterial wall of these vessels for instance, or an elevated stiffness of their walls could indicate the early onset of vascular disease and an increased total cardiovascular risk. This thesis contains a number of methodological studies investigating the most optimal way of measuring these and other vascular parameters and exploring how these parameters can best be leveraged to gain knowledge of the status of the cardiovascular system. The parameters and approaches presented are then used on clinical data obtained from a large population study, the Asklepios Study, in which clinical and stiffness parameters of over 2,500 subjects aged between 35 and 55 years old were included. From the results of these analyses we could for instance demonstrate that in the age range covered by the Asklepios Study the stiffness of large elastic arteries increases at a faster rate in women than in men. Next to a proper understanding of how to measure and interpret arterial stiffness parameters, efficient use of these parameters in clinical practice requires a set of reference values to which values measured in an individual can be compared. This thesis also presents the results of an European study in which a database was constructed containing the clinical and stiffness parameter data from over 25,000 subjects from 13 different centers. Based on these data reference values for the clinically most relevant stiffness parameter (carotid-femoral pulse wave velocity) are proposed