Physiological research
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The microcirculation plays a crucial role in the interaction between blood and tissues both in physiological and pathophysiological states. Despite its critical role in numerous diseases including diabetes, hypertension, sepsis or multiple organ failure, methods for direct visualization and quantitative assessment of human microcirculation at the bedside are limited. ⋯ Thus, there is a great effort to validate OPS imaging for various clinical purposes. The principles of OPS imaging, validation studies, its advantages, limitations, methods of quantitative assessment and current experience in clinical practice are discussed.
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Physiological research · Jan 2003
ReviewEnteral nutrition and hepatosplanchnic region in critically ill patients - friends or foes?
Enteral nutrition (EN) is a preferred way of feeding in critically ill patients unless obvious contraindications such as ileus or active gastrointestinal bleeding are present. Early enteral nutrition as compared to delayed EN or total parenteral nutrition decreases morbidity in postsurgical and trauma patients. The hepatosplanchnic region plays a pivotal role in the pathophysiology of sepsis and multiple organ dysfunction syndrome. ⋯ Interestingly, the results of recent clinical studies suggest that early enteral nutrition may not be harmful even in patients with circulatory compromise. Nevertheless, possible onset of serious complications, the non-occlusive bowel necrosis in particular, have to be kept in mind. Unfortunately, there is only a limited number of clinically applicable monitoring tools for the effects of enteral nutrition in critically ill patients.
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Physiological research · Jan 2000
ReviewGastric tonometry and intramucosal pH--theoretical principles and clinical application.
Gastric or intestinal luminal tonometry is a method for monitoring critically ill patients. It offers an index of the adequacy of aerobic metabolism in a tissue that is particularly sensitive to alterations in its perfusion and oxygenation: the gut mucosa. It is based on the measuring the increase in tissue CO2 production that accompanies anaerobic metabolism. ⋯ From this measurement and from the arterial bicarbonate concentration gastric intramucosal pH (pHi) can be calculated, assuming that bicarbonate concentration in the gastric mucosal tissue is in equilibrium with systemic arterial bicarbonate. Despite possible clinical benefit from the measurement and the therapy of low pHi values in critically ill patients, the theoretical, experimental and pathophysiological implications for the monitoring of intramucosal acidosis in the gut are not yet fully understood. There are still some open methodological questions crucial for further clinical interpretation.