Cardiovascular alterations and management

This chapter reviews the support of cardiovascular function in the face of
many compromises to the system. It focuses on two of the most prevalent and fatal diseases affecting the heart: coronary heart disease and heart failure. These diseases are also a common comorbidity in elderly patients admitted to critical care units. The first section on coronary heart disease reviews the pathophysiological concepts of myocardial ischaemia and associated complications, with detailed consideration of the clinical implications, assessment and associated management. Heart failure is discussed in terms of the body’s compensatory mechanisms and the clinical sequelae and associated clinical features of heart failure. Nursing and medical management is outlined including the management of acute exacerbations of heart failure. Finally, other cardiovascular disorders commonly managed in critical care units are reviewed, ranging from other forms of heart failure to hypertensive emergencies and aortic aneurysms. The case study presented at the end of the chapter highlights the key aspects of the management of coronary heart disease and heart failure in patients admitted to critical care units.

Estimating the effect of long-term physical activity on cardiovascular disease and mortality: evidence from the Framingham Heart Study

OBJECTIVE: In the majority of studies, the effect of physical activity (PA) on cardiovascular disease (CVD) and mortality is estimated at a single time point. The impact of long-term PA is likely to differ. Our study objective was to estimate the effect of long-term adult-life PA compared with long-term inactivity on the risk of incident CVD, all-cause mortality and CVD-attributable mortality. DESIGN: Observational cohort study. SETTING: Framingham, MA, USA. PATIENTS: 4729 Framingham Heart Study participants who were alive and CVD-free in 1956. EXPOSURES: PA was measured at three visits over 30 years along with a variety of risk factors for CVD. Cumulative PA was defined as long-term active versus long-term inactive. MAIN OUTCOME MEASURES: Incident CVD, all-cause mortality and CVD-attributable mortality. RESULTS: During 40 years of follow-up there were 2594 cases of incident CVD, 1313 CVD-attributable deaths and 3521 deaths. Compared with long-term physical inactivity, the rate ratio of long-term PA was 0.95 (95% CI 0.84 to 1.07) for CVD, 0.81 (0.71 to 0.93) for all-cause mortality and 0.83 (0.72 to 0.97) for CVD-attributable mortality. Assessment of effect modification by sex suggests greater protective effect of long-term PA on CVD incidence (p value for interaction=0.004) in men (0.79 (0.66 to 0.93)) than in women (1.15 (0.97 to 1.37)). CONCLUSIONS: Cumulative long-term PA has a protective effect on incidence of all-cause and CVD-attributable mortality compared with long-term physical inactivity. In men, but not women, long-term PA also appears to have a protective effect on incidence of CVD.

Higher dietary calcium intakes are associated with reduced risks of fractures, cardiovascular events, and mortality: a prospective cohort study of older men and women

The aim of this population-based, prospective cohort study was to investigate long-term associations between dietary calcium intake and fractures, non-fatal cardiovascular disease (CVD), and death from all causes. Participants were from the Melbourne Collaborative Cohort Study, which was established in 1990 to 1994. A total of 41,514 men and women (∼99% aged 40 to 69 years at baseline) were followed up for a mean (SD) of 12 (1.5) years. Primary outcome measures were time to death from all causes (n = 2855), CVD-related deaths (n = 557), cerebrovascular disease-related deaths (n = 139), incident non-fatal CVD (n = 1827), incident stroke events (n = 537), and incident fractures (n = 788). A total of 12,097 participants (aged ≥50 years) were eligible for fracture analysis and 34,468 for non-fatal CVD and mortality analyses. Mortality was ascertained by record linkage to registries. Fractures and CVD were ascertained from interview ∼13 years after baseline. Quartiles of baseline energy-adjusted calcium intake from food were estimated using a food-frequency questionnaire. Hazard ratios (HR) and odds ratios (OR) were calculated for quartiles of dietary calcium intake. Highest and lowest quartiles of energy-adjusted dietary calcium intakes represented unadjusted means (SD) of 1348 (316) mg/d and 473 (91) mg/d, respectively. Overall, there were 788 (10.3%) incident fractures, 1827 (9.0%) incident CVD, and 2855 people (8.6%) died. Comparing the highest with the lowest quartile of calcium intake, for all-cause mortality, the HR was 0.86 (95% confidence interval [CI] 0.76-0.98, ptrend  = 0.01); for non-fatal CVD and stroke, the OR was 0.84 (95% CI 0.70-0.99, ptrend  = 0.04) and 0.69 (95% CI 0.51-0.93, ptrend  = 0.02), respectively; and the OR for fracture was 0.70 (95% CI 0.54-0.92, ptrend  = 0.004). In summary, for older men and women, calcium intakes of up to 1348 (316) mg/d from food were associated with decreased risks for fracture, non-fatal CVD, stroke, and all-cause mortality.

Risk of cardiovascular disease and diabetes in a working population with sedentary occupations

OBJECTIVE: To assess the prevalence of risk factors and risk for cardiovascular disease and Type 2 diabetes in employees with sedentary occupations enrolled in a workplace health-promotion program. METHODS: Participants (n = 762) were recruited from ten Melbourne workplaces, participating in a physical activity program. Demographic, behavioral, biomedical, and physical measurements were collected. RESULTS: The majority of employees were not meeting recommended guidelines for physical activity (62%), fruit intake (70%), vegetable intake (86%), body mass index (58%), or waist circumference (53%). Most had intermediate (53%) or high (7%) risk of developing Type 2 diabetes. CONCLUSIONS: The majority of Australian adults in sedentary occupations were not meeting guidelines for a number of chronic disease risk factors and a substantial proportion were unaware of their increased risk. This study supports the potential of chronic disease risk factor detection and intervention programs in the workplace.

Valuation and reporting of native fauna in monetary terms: compatibility between a market-Based system and natural resources?

A change in community values and priorities has introduced ethical,
environmental and social issues into the way in which business conducts
its activities. There are an increasing number of managed investment funds focusing on socially responsible investment (SRI) by concentrating on firms that operate according to predetermined criteria for environmental, social and ethical issues. For investors in these funds environmental stewardship issues are integrated with concern over financial resources and performance. In this paper the accounting and reporting by business activities concerned with conservation of wildlife are examined. The world of accounting has functioned for many years with relatively few accounting standards devoted to specialised industry needs. In 1998 the Australian Accounting Standards Board and in 2001 the International Accounting Standards Board issued standards devoted to agriculture. Both standards deal with the reporting of managed biological assets and require application of essentially the same approaches despite the Australian standard requiring net market value while the International standard requires fair value. In this paper we analyse how one conservation firm Earth Sanctuaries Ltd. (ESL) has applied AASB 1037 and then we explore the implications for conservation firms operating in geographical locations outside Australia. It is suggested that AASB 1037 and indeed lAS 41 may not provide value appropriate information for investor decisions relating to accounting profits for such firms. Our examination shows that it is appropriate to reconsider accounting guidelines provided by these standards in order to link the information relating to economic and environmental performance. Transparency may be improved by a move closer to Elkington 's (1997) triple bottom line reporting. We therefore contend that the issues arising from the use ofAASB 1037 and lAS 41 need to be widely considered by all standard setters, particularly given the increasing attention to SRI.

Effect of a weight-loss program on mental stress-induced cardiovascular responses and recovery

Objective: We assessed the effect of weight loss on blood pressure (BP) and pulse rate during rest, psychological stress, and recovery after stress.

Methods: Two groups of men completed two mental stress tests 12 wk apart. The control group continued their usual diet, whereas the weight-loss group underwent a dietary weight-loss program in which they were randomized to a high-fruit/vegetable and low-fat dairy diet or a low-fat diet.

Results: Fifty-five men with a baseline BP of 125.9 ± 6.9/83.6 ± 7.1 mmHg (mean ± SD) completed the study (weight-loss group, n = 28; control group, n = 27). The weight-loss group lost weight (mean ± SEM, −4.3 ± 0.3 versus +0.4 ± 0.4 kg, P = 0.001) compared with controls and had a significant decrease in resting systolic BP (SBP; −2.0 ± 1.1% versus +2.0 ± 1.1%, P < 0.05). There was a greater decrease in SBP (P < 0.05) and pulse rate (P < 0.05) at all time points during the stress test in the weight loss compared with the control group. At week 12, SBP in 23 (82%) subjects in the weight-loss group and 24 (89%) in the control group returned to resting levels, with recovering levels in the weight-loss group returning to resting levels 6.1 ± 2.6 min earlier than in the control group (P < 0.05). There was an overall greater decrease in diastolic BP (DBP; P < 0.05) and DBP during recovery up to 27 min after stress (P < 0.05) in the high-fruit/vegetable and low-fat dairy diet group (n = 14) compared with the low-fat diet group (n = 14).

Conclusion: A 5% loss of weight decreased BP during rest and returned SBP to resting levels faster, thus decreasing the period of increased BP as a result of mental stress, which is likely to lower the risk of cardiovascular disease in the long term.

A medium-temperature solar thermal power system and its efficiency optimisation

This paper firstly expounds that the reheat-regenerative Rankine power cycle is a suitable cycle for the parabolic trough collector, a popular kind of collector in the power industry. In a thermal power cycle, the higher the temperature at which heat is supplied, the higher the efficiency of the cycle. On the other hand, for a given kind of collector at the same exiting temperature, the higher the temperature of the fluid entering the collector, the lower the efficiency of the collector. With the same exiting temperature of the solar field and the same temperature differences at the hottest end of the superheater/reheater and at the pinch points in the heat exchangers (e.g., the boiler) in the cycle, the efficiencies of the system are subject to the temperature of the fluid entering the collector or the saturation temperature at the boiler. This paper also investigates the optimal thermal and exergetic efficiencies for the combined system of the power cycle and collector. To make most advantage of the collector, the exiting fluid is supposed to be at the maximum temperature the collector can harvest. Hence, the thermal and exergetic efficiencies of the system are related to the saturation temperature at the boiler here.

Environmental management system and electronic communication : Is it the need of the hour?

Implementation and certification of Environmental Management Systems (EMS) is a reality for many businesses. Communication with an organisation’s stakeholders is a required element of any EMS. In the last five years companies have steadily moved towards integrating their different management systems, such as quality, environmental, and occupational health and safety, in an attempt to reduce their costs and increase efficiency. Legislation requires extensive reporting in each of these areas, so compliance is another important driver. During this period, communication by digital technology, or electronic communication, has gained prominence and acceptance amongst all groups of people including businesses primarily as a means to disseminate crucial EMS information to geographically diverse employees in a cost effective and instantaneous manner. Some perspectives have emerged to suggest that change processes in organisations may be hindered or helped in various ways through the application of digital technology in EMS. There are, however, gaps in the literature that document the impact and effectiveness of electronic communication amongst EMS stakeholders. In this paper we will discuss employees as one of the major stakeholders and whether the move to electronic communication has been assisting or hindering transformations in awareness and understanding of issues amongst employees. We highlight opportunities and challenges presented by an increased use of electronic communication in light of the environmental and climate change debates, which underpin EMS.

A systematic policy approach to changing the food system and physical activity environments to prevent obesity

As obesity prevention becomes an increasing health priority in many countries, including Australia
and New Zealand, the challenge that governments are now facing is how to adopt a systematic
policy approach to increase healthy eating and regular physical activity. This article sets out a
structure for systematically identifying areas for obesity prevention policy action across the food
system and full range of physical activity environments. Areas amenable to policy intervention can
be systematically identified by considering policy opportunities for each level of governance (local,
state, national, international and organisational) in each sector of the food system (primary
production, food processing, distribution, marketing, retail, catering and food service) and each
sector that influences physical activity environments (infrastructure and planning, education,
employment, transport, sport and recreation). Analysis grids are used to illustrate, in a structured
fashion, the broad array of areas amenable to legal and regulatory intervention across all levels of
governance and all relevant sectors. In the Australian context, potential regulatory policy
intervention areas are widespread throughout the food system, e.g., land-use zoning (primary
production within local government), food safety (food processing within state government), food
labelling (retail within national government). Policy areas for influencing physical activity are
predominantly local and state government responsibilities including, for example, walking and
cycling environments (infrastructure and planning sector) and physical activity education in schools
(education sector). The analysis structure presented in this article provides a tool to systematically
identify policy gaps, barriers and opportunities for obesity prevention, as part of the process of
developing and implementing a comprehensive obesity prevention strategy. It also serves to
highlight the need for a coordinated approach to policy development and implementation across
all levels of government in order to ensure complementary policy action.

Monitoring the performance of a microkernel based operating system and supported applications

The message passing microkernel based operating system is a class of operating system in which the policies are implemented using servers whose co-operation is supported by using a small hardware dependent layer called a microkernel. This thesis addresses the issue of reducing the performance deficiency by documenting the synthesis, development, implementation and assessment of a methodology and mechanisms for monitoring the performance of a message passing microkernel based operating system and supported processes. The methodology has been extensively evaluated to ensure that it can be used successfully to monitor performance.

Nitric oxide and vascular regulation in fishes and amphibians

Nitric oxide is an important molecule in the regulation of the cardiovascular system and blood pressure. This research provided new insights into the evolution of nitric oxide control of blood vessels by showing how nitric oxide signalling causes vasodilation in the circulation of amphibians and fishes.