The Regulation of Skeletal and Cardiac Muscle Blood Flow in Humans. Studies by positron emission tomography with special reference to exercise, adenosine and nitric oxide

Virtually every cell and organ in the human body is dependent on a proper oxygen supply. This is taken care of by the cardiovascular system that supplies tissues with oxygen precisely according to their metabolic needs. Physical exercise is one of the most demanding challenges the human circulatory system can face. During exercise skeletal muscle blood flow can easily increase some 20-fold and its proper distribution to and within muscles is of importance for optimal oxygen delivery. The local regulation of skeletal muscle blood flow during exercise remains little understood, but adenosine and nitric oxide may take part in this process. In addition to acute exercise, long-term vigorous physical conditioning also induces changes in the cardiovasculature, which leads to improved maximal physical performance. The changes are largely central, such as structural and functional changes in the heart. The function and reserve of the heart’s own vasculature can be studied by adenosine infusion, which according to animal studies evokes vasodilation via it’s a_2A receptors. This has, however, never been addressed in humans in vivo and also studies in endurance athletes have shown inconsistent results regarding the effects of sport training on myocardial blood flow. This study was performed on healthy young adults and endurance athletes and local skeletal and cardiac muscle blod flow was measured by positron emission tomography. In the heart, myocardial blood flow reserve and adenosine A_2A receptor density, and in skeletal muscle, oxygen extraction and consumption was also measured. The role of adenosine in the control of skeletal muscle blood flow during exercise, and its vasodilator effects, were addressed by infusing competitive inhibitors and adenosine into the femoral artery. The formation of skeletal muscle nitric oxide was also inhibited by a drug, with and without prostanoid blockade. As a result and conclusion, it can be said that skeletal muscle blood flow heterogeneity decreases with increasing exercise intensity most likely due to increased vascular unit recruitment, but exercise hyperemia is a very complex phenomenon that cannot be mimicked by pharmacological infusions, and no single regulator factor (e.g. adenosine or nitric oxide) accounts for a significant part of exercise-induced muscle hyperemia. However, in the present study it was observed for the first time in humans that nitric oxide is not only important regulator of the basal level of muscle blood flow, but also oxygen consumption, and together with prostanoids affects muscle blood flow and oxygen consumption during exercise. Finally, even vigorous endurance training does not seem to lead to supranormal myocardial blood flow reserve, and also other receptors than A_2A mediate the vasodilator effects of adenosine. In respect to cardiac work, atheletes heart seems to be luxuriously perfused at rest, which may result from reduced oxygen extraction or impaired efficiency due to pronouncedly enhanced myocardial mass developed to excel in strenuous exercise.

Immediate Decision-Making and Information Needs in Intensive Care Coordination

The aim of this study was to develop a theoretical model for information integration to support the deci¬sion making of intensive care charge nurses, and physicians in charge – that is, ICU shift leaders. The study focused on the ad hoc decision-making and immediate information needs of shift leaders during the management of an intensive care unit’s (ICU) daily activities. The term ‘ad hoc decision-making’ was defined as critical judgements that are needed for a specific purpose at a precise moment with the goal of ensuring instant and adequate patient care and a fluent flow of ICU activities. Data collection and research analysis methods were tested in the identification of ICU shift leaders’ ad hoc decision-making. Decision-making of ICU charge nurses (n = 12) and physicians in charge (n = 8) was observed using a think-aloud technique in two university-affiliated Finnish ICUs for adults. The ad hoc decisions of ICU shift leaders were identified using an application of protocol analysis. In the next phase, a structured online question¬naire was developed to evaluate the immediate information needs of ICU shift leaders. A national survey was conducted in all Finnish, university-affiliated hospital ICUs for adults (n = 17). The questionnaire was sent to all charge nurses (n = 515) and physicians in charge (n = 223). Altogether, 257 charge nurses (50%) and 96 physicians in charge (43%) responded to the survey. The survey was also tested internationally in 16 Greek ICUs. From Greece, 50 charge nurses out of 240 (21%) responded to the survey. A think-aloud technique and protocol analysis were found to be applicable for the identification of the ad hoc decision-making of ICU shift leaders. During one day shift leaders made over 200 ad hoc decisions. Ad hoc decisions were made horizontally, related to the whole intensive care process, and vertically, concerning single intensive care incidents. Most of the ICU shift leaders’ ad hoc decisions were related to human resources and know-how, patient information and vital signs, and special treatments. Commonly, this ad hoc decision-making involved several multiprofessional decisions that constituted a bundle of immediate decisions and various information needs. Some of these immediate information needs were shared between the charge nurses and the physicians in charge. The majority of which concerned patient admission, the organisation and management of work, and staff allocation. In general, the information needs of charge nurses were more varied than those of physicians. It was found that many ad hoc deci-sions made by the physicians in charge produced several information needs for ICU charge nurses. This meant that before the task at hand was completed, various kinds of information was sought by the charge nurses to support the decision-making process. Most of the immediate information needs of charge nurses were related to the organisation and management of work and human resources, whereas the information needs of the physicians in charge mainly concerned direct patient care. Thus, information needs differ between professionals even if the goal of decision-making is the same. The results of the international survey confirmed these study results for charge nurses. Both in Finland and in Greece the information needs of charge nurses focused on the organisation and management of work and human resources. Many of the most crucial information needs of Finnish and Greek ICU charge nurses were common. In conclusion, it was found that ICU shift leaders make hundreds of ad hoc decisions during the course of a day related to the allocation of resources and organisation of patient care. The ad hoc decision-making of ICU shift leaders is a complex multi-professional process, which requires a lot of immediate information. Real-time support for information related to patient admission, the organisation and man¬agement of work, and allocation of staff resources is especially needed. The preliminary information integration model can be applied when real-time enterprise resource planning systems are developed for intensive care daily management

Improving oral healthcare in Scotland with special reference to sustainability and caries prevention

Brett Duane Improving oral healthcare in Scotland with special reference to sustainability and caries prevention University of Turku, Faculty of Medicine, Institute of Dentistry, Community Dentistry, Finnish Doctoral Program in Oral Sciences (FINDOS-Turku), Turku, Finland Annales Universitatis Turkuensis, Sarja- Ser. D, Medica-Odontologica. Painosalama Oy, Turku, Finland, 2015. Dentistry must provide sustainable, evidence-based, and prevention-focused care. In Scotland oral health prevention is delivered through the Childsmile programme, with an increasing use of high concentration fluoride toothpaste (HCFT). Compared with other countries there is little knowledge of xylitol prevention. The UK government has set strict carbon emission limits with which all national health services (NHS) must comply. The purpose of these studies was firstly to describe the Scottish national oral health prevention programme Childsmile (CS), to determine if the additional maternal use of xylitol (CS+X) was more effective at affecting the early colonisation of mutans streptococci (MS) than this programme alone; secondly to analyse trends in the prescribing and management of HCFT by dentists; and thirdly to analyse data from a dental service in order to improve its sustainability. In all, 182 mother/child pairs were selected on the basis of high maternal MS levels. Motherswere randomly allocated to a CS or CS+X group, with both groups receiving Childsmile. Theintervention group consumed xylitol three times a day, from when the child was 3 months until 24 months. Children were examined at age two to assess MS levels. In order to understand patterns of HCFT prescribing, a retrospective secondary data analysis of routine prescribing data for the years 2006-2012 was performed. To understand the sustainability of dental services, carbon accounting combined a top-down approach and a process analysis approach, followed by the use of Pollard’s decision model (used in other healthcare areas) to analyse and support sustainable service reconfiguration. Of the CS children, 17% were colonised with MS, compared with 5% of the CS+X group. This difference was not statistically significant (P=0.1744). The cost of HCFT prescribing increased fourteen-fold over five years, with 4% of dentists prescribing 70% of the total product. Travel (45%), procurement (36%) and building energy (18%) all contributed to the 1800 tonnes of carbon emissions produced by the service, around 4% of total NHS emissions. Using the analytical model, clinic utilisation rates improved by 56% and patient travel halved significantly reducing carbon emissions. It can be concluded that the Childsmile programme was effective in reducing the risk for MS transmission. HCFT is increasing in Scotland and needs to be managed. Dentistry has similar carbon emissions proportionally as the overall NHS, and the use of an analytic tool can be useful in helping identify these emissions. Key words: Sustainability, carbon emissions, xylitol, mutans streptococci, fluoride toothpaste, caries prevention.

The discourse on political pluralism in early eighteenth-century England : a conceptual study with special reference to terminology of religious origin

Doctoral dissertation, University of Jyväskylä