Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.

Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability

The contract state, trust distortion, and efficiency

In this paper we challenge the Public Choice-Agency Theory approach, which characterizes economic transactions as a series of discrete, unique events. We argue that the policy implications flowing from this view of the world are flawed, as they ignore the role of trust in contract formation and execution. Evidence is drawn from health, local authority, and water service sectors of the economy to illustrate the way in which the efficiency-enhancing properties of contract-based provision may be attenuated if trust is distorted by institutional change

A Mixed Learning Approach in Mechatronics Education

During the last decade the water industry throughout Great Britain has undergone its most radical restructuring in over half a century. In England and Wales privatisation of the ten regional water authorities in 1989 removed the industry from the public sector at a stroke. In Scotland the privatisation option was rejected, and responsibility for water and sewerage services was instead transferred from local to central government control through the creation of three public water authorities in 1996. Despite these fundamental differences, however, domestic customers on both sides of the border have faced increases in thencharges, year on year, well above the rate of inflation. In Scotland these increases have been underpinned by the need for additional capital investment, tariff harmonisation across water authority areas and reductions in central government financial support in the form of transitional relief for sewerage services. The statutory body established to protect consumer interests - the Scottish Water and Sewerage Customers Council - has viewed the sharp rise in prices with increasing concern, taking the controversial step of rejecting the 1998/99 water authority charging proposals in January 1998. The final settlement determined by the Secretary of State for Scotland allowed these increases to stand, but arranged a redistribution of the transitional relief grant of £30 million to limit the effect of the price rises on low-income households. For the 1999/2000 determination transitional relief was phased out completely, leading to rises in average domestic water bills of the order of 20%. Against this background our paper analyses the distributional impact of water and sewerage price rises on domestic households in Scotland. Following the introduction, section two contains a brief theoretical discussion and an analysis of the recent charging reforms in Scotland. In section three we employ data from the Family Resources Survey, a source not used previously in this context, to examine the relative burden of water and sewerage charges on households classified according to income, property value and geographical location. Section four discusses the policy implications of the analysis and section five concludes

Money, Sex and Religion: The case of the Church of Scotland

This empirical study addresses whether the gender of a minister has any effect on remuneration in the Church of Scotland in 2004. The data set merges three cross-sectional sources, namely denominational data, church census information and local geographic (postcode) characteristics. We find that male ministers are more likely to be matched to affluent churches permitted to pay a voluntary stipend premium all else equal. Moreover, conditional on eligibility, there is evidence that male clergy are more likely to receive this bonus. The data are unable to discriminate between demand and supply side explanations of these findings.</p

Chemistry of Polymer and Ceramic-Based Injectable Scaffolds and Their Applications in Regenerative Medicine

Injectable scaffolds are a class of materials that stimulate the regeneration of functional tissue within the body. These materials are attracting interest in regenerative medicine because they allow tissue repair to occur after minimally invasive administration. From a chemistry perspective these materials present new challenges because they must convert from an injectable material to a solid or gel with appropriate kinetics and without damaging surrounding tissues. Furthermore, the material may have to carry living cells or sensitive drug molecules into the body. The demands placed on these materials have stimulated research into novel chemical and physical mechanisms of forming porous structures within aqueous conditions. This review examines the underlying chemistry of a number of classes of injectable scaffolds and sets out challenges for these materials in the future