Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference
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Conf Proc IEEE Eng Med Biol Soc · Jan 2004
Cardiac output monitoring in intensive care patients by radial artery pressure waveform analysis.
We have developed a novel technique for monitoring cardiac output (CO) changes by mathematically analyzing a single peripheral arterial blood pressure (ABP) waveform. In contrast to all previous techniques, our technique analyzes the ABP waveform over time scales greater than a cardiac cycle in which complex wave reflections are attenuated. ⋯ We report an overall error in the technique of 18.1% with respect to the error-prone clinical thermodilution measurements. This study promotes thorough future testing of the technique in humans.
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Conf Proc IEEE Eng Med Biol Soc · Jan 2004
Continuous blood pressure monitoring during exercise using pulse wave transit time measurement.
This paper gives an overview of a research, which is focused on the development of the convenient device for continuous non-invasive monitoring of arterial blood pressure. The blood pressure estimation method is based on a presumption that there is a singular relationship between the pulse wave propagation time in arterial system and blood pressure. The parameter used in this study is pulse wave transit time (PWTT). ⋯ The reliability of beat to beat systolic blood pressure calculation during physical exercise was the main focus for the current paper. Sixty-one subjects (healthy and hypertensive) were studied with the bicycle exercise test. As a result of current study it is shown that with the correct personal calibration it is possible to estimate the beat to beat systolic arterial blood pressure during the exercise with comparable accuracy to conventional noninvasive methods.
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Conf Proc IEEE Eng Med Biol Soc · Jan 2004
The effect of age on the grip force control in lateral grip.
In the paper we present the grip force tracking system for the evaluation of grip force control. We developed a grip measuring device which can be used for the computer assisted measurements of the grip force in real time. The device was used as an input to a force-tracking task where the subject applied the grip force according to the visual feedback from the computer screen. ⋯ The largest variability among subjects was observed in the group of children and older adults. No significant difference in force control was found between the dominant and non-dominant hand. The grip force tracking system presented is aimed to be used for the evaluation of grip force control in patients with different sensory-motor impairments.
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Conf Proc IEEE Eng Med Biol Soc · Jan 2004
Lifeguard--a personal physiological monitor for extreme environments.
Monitoring vital signs in applications that require the subject to be mobile requires small, lightweight, and robust sensors and electronics. A body-worn system should be unobtrusive, noninvasive, and easy-to-use. It must be able to log vital signs data for several hours as well as transmit it on demand in real-time using secure wireless technologies. The NASA Ames Research Center (Astrobionics) and Stanford University (National Center for Space Biological Technologies) are currently developing a wearable physiological monitoring system for astronauts, called LifeGuard, that meets all of the above requirements and is also applicable to clinical, home-health monitoring, first responder and military applications.
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Conf Proc IEEE Eng Med Biol Soc · Jan 2004
A comprehensive physiological model of circulation enables automatic piloting of hemodynamics in patients with acute heart failure.
A comprehensive physiological model of the whole circulation is mandatory to quantitatively diagnose pathophysiology and to guide an appropriate treatment. Such a model would enable automatic piloting of hemodynamics in patients with acute heart failure. By extending Guyton's model, so as to deal with heart failure predominantly affecting left heart and to quantify left atrial pressure, we constructed such a model consisting of a venous return (VR) surface and a cardiac output (CO) curve. ⋯ Using these, we could accurately predict CO (y = 0.93x + 6.5, r2 = 0.96, Figure 2), P(RA) (y = 0.87x + 0.4, r2 = 0.91) and P(LA) (y = 0.90x + 0.48, r2 = 0.93). Our comprehensive physiological model of circulation is useful in accurately predicting hemodynamics from the measurement of a single set of CO, P(RA) and (P(LA) following blood volume changes. Therefore, this model enables continuous monitoring of blood volume and pump performance for automatic hemodynamic piloting.