Summary: | In the acute phase of stroke, ischaemic brain may be particularly vulnerable to mild hypoxia or hypotension which could lessen the potential for neuronal recovery and hence a good outcome after stroke. Particular causes for concern are: hypoxia and hypotension resulting from routine positioning in bed (for immobile patients); and aspiration and chest infections associated with impaired swallowing and respiratory control. Positioning and feeding strategies are largely nursing responsibilities; there is little evidence that current practices are optimal or evidence based to achieve the best possible outcome for patients. The aim of this thesis was to evaluate the influence of nursing practices for patient positioning and feeding in the acute phase of stroke on oxygenation, blood pressure and heart rate to see whether potentially serious hypoxic and hypotensive episodes were occurring, which if avoided, might improve neurological and general physical outcome after stroke. This thesis included a thorough systematic review of all previous studies to measure physiological variables during the positioning or feeding of stroke patients. The review highlighted that a new study was necessary as previous studies included a number of serious methodological issues, such as patient selection, small sample size, equipment and measurement differences, and confounding. The thesis also considered the most accurate and clinically relevant way to measure physiological variables in acute stroke patients who are often agitated, confused, incontinent and extremely sick. Finally, it describes the results of two observational studies that were conducted in parallel and included over 300 acute stroke patients and control subjects. Both these studies were sufficiently powered to identify statistically significant and clinical relevant changes in oxygenation, blood pressure and heart rate during routine positioning and feeding of acute stroke patients by nurses.
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