Feasibility and efficacy of bypassing the right ventricle and pulmonary circulation to treat right ventricular failure: an experimental study

<p>Abstract</p> <p>Background</p> <p>Right ventricular failure (RVF) and -support is associated with poor results. We aimed for a new approach of right - sided assistance bypassing the right ventricle and pulmonary circulation in order to better decompress the right ventricle and optimize left ventricular filling.</p> <p>Methods</p> <p>From a microaxial pump (Abiomed), a low resistance oxygenator (Maquet and Novalung) and two cannulas (28 and 27 Fr) a system was set up and evaluated in an ovine model (n = 7). Connection with the heart was the right and left atrium. One hour the system was operated without RVF and turned of again. Then a RVF was induced and the course with the system running was evaluated. Complete hemodynamic monitoring was performed as well as echocardiography, flow measurement and blood gas analysis.</p> <p>Results</p> <p>The overall performance of the system was reliable. Without RVF no relevant changes of hemodynamics occurred; blood gases were supra normal. In RVF a cardiogenic shock developed (MAP 35 ± 13 mmHg, CO 1,1 ± 0,7 l/min). Immediately after starting the system the circulation normalized (significant increase of MAP to 85 ± 13 mmHg, of CO to 4,5 ± 1,9). Echocardiography also revealed right ventricular recovery. After stopping the system, RVF returned.</p> <p>Conclusions</p> <p>Bypassing the right ventricle and pulmonary circulation with an oxygenating assist device, which may offer the advantages of enhanced right ventricular decompression and augmented left atrial filling, is feasible and effective in the treatment of acute RVF. Long time experiments are needed.</p

Red blood cell alloimmunisation in transfusion-dependent thalassaemia: a systematic review.

BACKGROUND: Chronic red blood cell transfusion is the first-line treatment for severe forms of thalassaemia. This therapy is, however, hampered by a number of adverse effects, including red blood cell alloimmunisation. The aim of this systematic review was to collect the current literature data on erythrocyte alloimmunisation. MATERIALS AND METHODS: We performed a systematic search of the literature which identified 41 cohort studies involving 9,256 patients. RESULTS: The prevalence of erythrocyte alloimmunisation was 11.4% (95% CI: 9.3-13.9%) with a higher rate of alloimmunisation against antigens of the Rh (52.4%) and Kell (25.6%) systems. Overall, alloantibodies against antigens belonging to the Rh and Kell systems accounted for 78% of the cases. A higher prevalence of red blood cell alloimmunisation was found in patients with thalassaemia intermedia compared to that among patients with thalassaemia major (15.5 vs 12.8%). DISCUSSION: Matching transfusion-dependent thalassaemia patients and red blood cell units for Rh and Kell antigens should be able to reduce the risk of red blood cell alloimmunisation by about 80%

Thomas Aquinas on the Ontology of the Political Community

Aquinas never discusses the ontology of those entities that we today consider signifcant for social ontology. On some occasions, however, he addresses the mereological question of the relation between social aggregates and the individuals that compose them, and these places are signifcant for bringing to light what Aquinas had to say, if anything, about social ontology. In this contributio I prove that Aquinas’s analysis of social aggregates is essentially metaphysical and that, in the end, it leads him to assign a place to such aggregates within Aristotelian ontology. Nevertheless, cognitive and linguistic considerations, which concern what we can call collective intentionality and the constitutive role of some speech acts, play some role in Aquinas's explanation of the nature and origin of social aggregates. Aquinas’s view of social ontology lies between reductionism and realism with respect to the question of the nature of social aggregates, and between naturalism and constructionism with respect to the question of their origin

Thomas Aquinas and Some Italian Dominicans (Francis of Prato, Georgius Rovegnatinus and Girolamo Savonarola) on Signification and Supposition

Supposition is a controversial logical theory. Scholars have investigated many points of this doctrine such as its historical origin, its use in theology, the logical function of the theory, or the relationship between supposition and signification. In the article I focus on this latter aspect by discussing how some Italian, and in particular Florentine, Dominican followers of Aquinas—Francis of Prato (d. 1348), Girolamo Savonarola (d. 1498), and Georgius Rovegnatinus (d. after 1500)—explained the relation between the linguistic terms’ properties of signifying and suppositing, and hence the division of supposition. After sketching out Thomas Aquinas, Hervaeus Natalis, and William of Ockham’s positions on the relationship between signification and supposition, I closely examine Francis’s criticism of Ockham. Francis follows Walter Burley’s account of supposition and considers the statement that a term has simple supposition when (i) it is taken not significatively and (ii) stands for an intention of mind as the weak point of Ockham’s explanation of supposition. According to Francis, if this were the case, there would be no semantic basis for differentiating simple from material supposition. Francis is however hesitant about the full subordination of supposition to signification, especially with regards to material supposition, when a term, suppositing for itself, is taken to signify itself besides its meaning. More than one hundred years later, Girolamo Savonarola and Georgius Rovegnatinus have no doubt about the fact that terms may supposit only for what they signify

Il rasoio di Chatton. La disputa tra Chatton e Ockham sul principio di parsimonia

Il presente contributo ripensa la natura del celebre 'rasoio di Ockham'. In primo luogo, nell'articolo si mostra come Ockham abbia adottato il principio di economia come principio ispiratore della propria filosofia dopo che un confratello inglese, Walter Chatton, lo aveva adoperato contro di lui. In secondo luogo, si argomenta che il 'rasoio di Chatton', a dispetto della sua formulazione, non rappresenta un 'anti-rasoio' come invece viene comunemente presentato in letteratura

14th-Century Reactions to Burley

The chapter focuses on some of the 14th-Century reactions to Walter Burley, one of the most important logician and metaphysician of the late Middle Ages. Burley's thought was influent in many areas of philosophy and at different degrees. The chapter selects some of them, illustrating the reactions to his philosophy of logic and metaphysics which took place at the Universities of Oxford and Paris