Physiological measurement
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Physiological measurement · Jul 2006
ReviewSublingual capnometry: a non-invasive measure of microcirculatory dysfunction and tissue hypoxia.
With improvement in supportive care patients rarely die from their presenting illness but rather from its sequela, namely sequential multi-organ failure. Tissue hypoxia is believed to be the causation of multi-organ dysfunction syndrome (MODS). The expedient detection and correction of tissue hypoxia may therefore limit the development of MODS. ⋯ Global 'downstream' markers such as mixed venous oxygen saturation and blood lactate are insensitive indicators of tissue hypoxia. Sublingual PCO(2) is a regional marker of microvascular perfusion and tissue hypoxia that holds great promise for the risk stratification and end-point of goal directed resuscitation in critically ill patients. This paper reviews the technology and application of sublingual PCO(2) monitoring.
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Physiological measurement · Jul 2006
Comparative StudyA longitudinal study of methanol in the exhaled breath of 30 healthy volunteers using selected ion flow tube mass spectrometry, SIFT-MS.
Selected ion flow tube mass spectrometry, SIFT-MS, has been used to monitor the volatile compounds in the exhaled breath of 30 volunteers (19 male, 11 female) over a six-month period. Volunteers provided breath samples each week between 8:45 am and 1 pm (before lunch), and the concentrations of several trace compounds were obtained. In this paper the focus is on methanol in breath. ⋯ Breath methanol is not correlated with age, breath ethanol or ethanol consumed in the previous 24 h, but there was an inverse correlation with body mass index (BMI) for the cohort of volunteers recruited for this study. Observed breath methanol levels are well compatible with the previously published blood methanol levels. Some tentative suggestions are made concerning the origin of endogenous methanol.
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Physiological measurement · Jul 2006
Comment LetterComments on 'The influence of cardiac preload and positive end-expiratory pressure on the pre-ejection period'.
The pre-ejection period (PEP) has been described as a potential parameter for monitoring cardiac preload in deeply sedated mechanically ventilated patients. Other authors have recently suggested that PEP is not sensitive to the changes in intravascular volume status in mechanically ventilated pigs which underwent acute hemorrhage. The present comment is an analysis of this recent animal investigation.