Journal of clinical monitoring and computing
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In the present review we will describe and discuss the physiological and technological background necessary in understanding the dynamic parameters of fluid responsiveness and how they relate to recent softwares and algorithms' applications. We will also discuss the potential clinical applications of these parameters in the management of patients under general anesthesia and mechanical ventilation along with the potential improvements in the computational algorithms.
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J Clin Monit Comput · Feb 2011
ReviewAcid-base chemistry of plasma: consolidation of the traditional and modern approaches from a mathematical and clinical perspective.
Debate still exists as to whether the Stewart (modern) or traditional model of acid-base chemistry is best in assessing the acid-base status of critically ill patients. Recent studies have compared various parameters from the modern and traditional approaches, assessing the clinical usefulness of parameters such as base excess, anion gap, corrected anion gap, strong ion difference and strong ion gap. To compare the clinical usefulness of these parameters, and hence the different approaches, requires a clear understanding of their meaning; a task only possible through understanding the mathematical basis of the approaches. The objective of this paper is to provide this understanding, limiting the mathematics to a necessary minimum. ⋯ Although different in their concepts, the traditional and modern approaches based on mathematical models can be seen as complementary giving, in principle, the same information about the acid-base status of plasma.
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J Clin Monit Comput · Feb 2011
ReviewAnesthesia information management systems: a review of functionality and installation considerations.
The functionality and rate of implementation of Anesthesia Information Management Systems (AIMS) has markedly risen over the past decade. These systems have now become much more than the generic automated record keepers, originally proposed and developed in the 1980s. AIMS have now become complex integrated systems, which have been shown to improve patient care and, in some cases, the financial performance of a department. Although the underlying technology has improved greatly over the past 5 years, the process of selecting and completing an AIMS installation still presents a number of challenges, and must be approached carefully in order to maximize the benefits provided by these systems.
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J Clin Monit Comput · Feb 2011
Dynamic behavior of BIS, M-entropy and neuroSENSE brain function monitors.
The objective of this paper is to assess the suitability of brain function monitors for use in closed-loop anesthesia or sedation delivery. In such systems, monitors used as feedback sensors should preferably be Linear and Time Invariant (LTI) in order to limit sensor-induced uncertainty which can cause degraded performance. In this paper, we evaluate the suitability of the BIS A2000 (Aspect Medical Systems, MA), the M-Entropy Monitor (GE HealthCare), and the NeuroSENSE Monitor (NeuroWave Systems Inc, OH), by verifying whether their dynamic behavior conforms to the LTI hypothesis. ⋯ While both BIS and M-Entropy monitors have been successfully used in closed-loop systems, we were unable to obtain a unique LTI model that could capture their dynamic behavior during step-wise changes in cortical activity. The uncertainty in their output during rapid changes in cortical activity impose limitations in the ability of the controller to compensate for rapid changes in patients' cortical state, and pose additional difficulties in being able to provide mathematically proof for the stability of the overall closed-loop system. Conversely, the NeuroSENSE dynamic behavior can be fully captured by a linear and time invariant transfer function, which makes it better suited for closed-loop applications.