Renal function, revascularization and risk

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Utility of B-type natriuretic peptide in predicting medium-term mortality in patients undergoing major non-cardiac surgery

We assessed the ability of pre-operative B-type natriuretic peptide (BNP) levels to predict medium-term mortality in patients undergoing major noncardiac surgery. During a median 654 days follow-up 33 patients from a total cohort of 204 patients (16%) died. The optimal cut-off in this cohort, determined using a receiver operating characteristic curve, was >35pg.mL-1. This was associated with a 3.47-fold increase in the hazard of death (p=0.001) and had a sensitivity of 70% and a specificity of 68% for this outcome. These findings extend recent work demonstrating that BNP levels obtained before major noncardiac surgery can be used to predict peri-operative morbidity, and indicate that they also forecast medium-term mortality.This work was supported by a grant from TENOVUS Scotland. The Health Services Research Unit is core-funded by the Chief Scientists Office of the Scottish Executive Health Department.Peer reviewedAuthor versio

Contemporary stress orientations in the Faroe-Shetland region

The Faroe-Shetland Region (FSR) of the NE Atlantic continental margin contains a number of complexly structured Mesozoic-Palaeogene-age rift basins, but in comparison to the contiguous British Isles and North Sea Basin, the state of crustal stress in the FSR is poorly understood. The orientation of maximum horizontal compressional stress (σHmax) across most of NW Europe is ~NW-SE, which is considered to be controlled by forces acting at the plate boundaries. We have determined 16 B-D quality σHmax orientations based on borehole breakouts interpreted in petroleum wells, and define three distinct stress provinces within the FSR. Stress orientations in the NE are ~NW-SE, consistent with the regional pattern of stresses in NW Europe and local neotectonic structural trends. However, contemporary stress orientations in the central and SW of the FSR exhibit short-wavelength (distances <10-50 km) variation, with NE-SW, N-S and E-W orientations that are parallel or sub-parallel to underlying structural trends. This variation is interpreted in terms of stress deflections towards weak faults that downthrow the Mesozoic-Cenozoic sedimentary successions against basement highs. These local-scale sources are superposed on a background ~WNW-ESE σHmax orientation that is controlled by both plate boundary forces and regional-scale sources of stresses

Preoperative neutrophil-lymphocyte ratio and outcome from coronary artery bypass grafting

Background: An elevated preoperative white blood cell count has been associated with a worse outcome after coronary artery bypass grafting (CABG). Leukocyte subtypes, and particularly the neutrophil-lymphocyte (N/L) ratio, may however, convey superior prognostic information. We hypothesized that the N/L ratio would predict the outcome of patients undergoing surgical revascularization. Methods: Baseline clinical details were obtained prospectively in 1938 patients undergoing CABG. The differential leukocyte was measured before surgery, and patients were followed-up 3.6 years later. The primary end point was all-cause mortality. Results: The preoperative N/L ratio was a powerful univariable predictor of mortality (hazard ratio [HR] 1.13 per unit, P 3.36). Conclusion: An elevated N/L ratio is associated with a poorer survival after CABG. This prognostic utility is independent of other recognized risk factors.Peer reviewedAuthor versio

Orphanhood and caregiver loss among children based on new global excess COVID-19 death estimates

The availability of new excess mortality data enables us to update global minimum estimates of COVID-19 orphanhood and caregiver death among children.1-4 Consequences for children can be devastating, including institutionalization, abuse, traumatic grief, mental health problems, adolescent pregnancy, poor educational outcomes, and chronic and infectious diseases.4,5 Global totals and country comparisons were previously hampered by inconsistencies in COVID-19 testing and incomplete death reporting. The new orphanhood estimates derived here based on excess deaths provide a comprehensive measure of COVID-19’s long-term impact on orphanhood and caregiver loss

The effectiveness and cost-effectiveness of computed tomography screening for coronary artery disease : systematic review

Coronary heart disease (CHD) is one of the main causes of mortality and morbidity in the UK and other Western countries. The disease can be asymptomatic until the first event, which may be a fatal myocardial infarction (heart attack). Half of all heart attacks occur in people who have had no prior warning of coronary disease, and almost half will die from the first attack. Risk scores based on well-known factors such as age, blood pressure, smoking, cholesterol and diabetes have been used to assess risk, but are imperfect: not all high-risk people develop heart disease, and many low-risk people do. Indeed, depending on which cut-off is used to define high risk, most heart attacks occur in low-risk people, because the number of people at low risk is much greater than the number at high risk. There is therefore a need for a better way of identifying those at risk so that they can treat themselves with lifestyle measures, or receive drug therapy such as statins and antihypertensive drugs as appropriate. Computed tomography (CT) is a form of radiological imaging that can detect calcium deposits in the coronary arteries. This calcification is a marker for CHD, and so CT imaging could be a way of detecting asymptomatic but serious CHD. CT is quick and non-invasive, but does involve a relatively large radiation dose

DC to AC Inverter for a Microgrid-Inspired Power Distribution Architecture for Electric Vehicles

This project builds upon the prototyping of a microgrid-inspired power distribution architecture for electric vehicles (EVs). The efficacy of this prototype aims to inform a full-scale power distribution system that charges an EV battery, supports the electric grid with important ancillary services, performs peer-to-peer EV charging, and works in conjunction with other AC and DC sources and loads. The scope of this report focuses specifically on the design, construction, and testing of the DC/AC inverter. Future development of this distribution architecture will incorporate synchronous generators, a battery management system, and an Arduino/Raspberry Pi-based communication system to fully simulate an electric vehicle’s design

Real-time wave excitation forces estimation: An application on the ISWEC device

Optimal control strategies represent a widespread solution to increase the extracted energy of a Wave Energy Converter (WEC). The aim is to bring the WEC into resonance enhancing the produced power without compromising its reliability and durability. Most of the control algorithms proposed in literature require for the knowledge of the Wave Excitation Force (WEF) generated from the incoming wave field. In practice, WEFs are unknown, and an estimate must be used. This paper investigates the WEF estimation of a non-linear WEC. A model-based and a model-free approach are proposed. First, a Kalman Filter (KF) is implemented considering the WEC linear model and the WEF modelled as an unknown state to be estimated. Second, a feedforward Neural Network (NN) is applied to map the WEC dynamics to the WEF by training the network through a supervised learning algorithm. Both methods are tested for a wide range of irregular sea-states showing promising results in terms of estimation accuracy. Sensitivity and robustness analyses are performed to investigate the estimation error in presence of un-modelled phenomena, model errors and measurement noise