Pharmacologic prophylaxis for atrial fibrillation following cardiac surgery: a systematic review

Atrial Fibrillation (AF) is the most common arrhythmia occurring after cardiac surgery. Its incidence varies depending on type of surgery. Postoperative AF may cause hemodynamic deterioration, predispose to stroke and increase mortality. Effective treatment for prophylaxis of postoperative AF is vital as reduces hospitalization and overall morbidity. Beta - blockers, have been proved to prevent effectively atrial fibrillation following cardiac surgery and should be routinely used if there are no contraindications. Sotalol may be more effective than standard b-blockers for the prevention of AF without causing an excess of side effects. Amiodarone is useful when beta-blocker therapy is not possible or as additional prophylaxis in high risk patients. Other agents such as magnesium, calcium channels blocker or non-antiarrhythmic drugs as glycose-insulin - potassium, non-steroidal anti-inflammatory drugs, corticosteroids, N-acetylcysteine and statins have been studied as alternative treatment for postoperative AF prophylaxis

Knowledge engineering in product and process design

A primary objective of knowledge engineering is to facilitate the application of knowledge arising from product design and the planning of the manufacturing process for new and modified products. Knowledge is an expensive and valuable commodity so the development of methods for its capture, representation and application are of considerable importance. The emphasis of the research described in this paper is on the re-use of knowledge for the creation of product variants. This implementation of ‘predictive design’ represents the very significant move from standard parts to standard knowledge constructs. Standard parts can be used in any application that requires a defined function where the shape and properties do not need to be altered. However, standard knowledge constructs can provide parts that can be used wherever the function is required. The Process Specification Language (PSL) provides one possible way of achieving this aim and is briefly outlined. A complementary method using ‘knowledge fragments’ for Failure Modes and Effects Analysis (FMEA) applied to electronic products is also described

The Pugh Controlled Convergence Method: Model-Based Evaluation and Implications for Design Theory

This paper evaluates the Pugh Controlled Convergence method and its relationship to recent developments in design theory. Computer executable models are proposed simulating a team of people involved in iterated cycles of evaluation, ideation, and investigation. The models suggest that: 1) convergence of the set of design concepts is facilitated by the selection of a strong datum concept; 2) iterated use of an evaluation matrix can facilitate convergence of expert opinion, especially if used to plan investigations conducted between matrix runs; and 3) ideation stimulated by the Pugh matrices can provide large benefits both by improving the set of alternatives and by facilitating convergence. As a basis of comparison, alternatives to Pugh's methods were assessed such as using a single summary criterion or using a Borda count. These models suggest that Pugh's method, under a substantial range of assumptions, results in better design outcomes than those from these alternative procedures