摘要:
One aspect of the invention relates to a system adapted to calibrate a determination of information related to one or more gaseous analytes in a body of gas being delivered to an objective by a gas source. In one embodiment the system comprises a partial pressure sensor, a total pressure monitor, a partial pressure module, and a calibration module. The partial pressure sensor generates an output signal related to the partial pressure of the one or more gaseous analytes in the body of gas. The total pressure monitor determines the total pressure of the body of gas. The partial pressure module determines the partial pressure of the one or more gaseous analytes in the body of gas according to a partial pressure function, wherein the partial pressure function describes the partial pressure of the one or more gaseous analytes in the body of gas as a function of the output signal generated by the partial pressure sensor. The calibration module that calibrates the partial pressure module by determining the partial pressure function.
摘要:
Methods for estimating the volume of the carbon dioxide stores of an individual's respiratory tract include determining a carbon dioxide store volume at which a correlation between corresponding signals of carbon dioxide elimination and an indicator of the content of carbon dioxide in blood of the individual is optimized. The estimate of the volume of carbon dioxide stores, which comprises a model of the respiratory tract, or lungs, of the individual, may be used as a transformation to improve the accuracy of one or both of the carbon dioxide elimination and carbon dioxide content signals. Transformation, or filtering, algorithms are also disclosed, as are systems in which the methods and algorithms may be used. The methods, algorithms, and systems may be used to accurately and noninvasively determine one or both of the pulmonary capillary blood flow and cardiac output of the individual.
摘要:
A system for measuring a metabolic parameter. The system includes an integrated airway adapter capable of monitoring any combination of respiratory flow, O2 concentration, and concentrations of one or more of CO2, N2O, and an anesthetic agent in real time, breath by breath. Respiratory flow may be monitored with differential pressure flow meters under diverse inlet conditions through improved sensor configurations which minimize phase lag and dead space within the airway. Molecular oxygen concentration may be monitored by way of luminescence quenching techniques. Infrared absorption techniques may be used to monitor one or more of CO2, N2O, and anesthetic agents.
摘要翻译:用于测量代谢参数的系统。 该系统包括能够监测呼吸流量O 2浓度的任何组合以及CO 2 2 N 2 N 2的一种或多种的浓度的集成气道适配器, / SUB> O,麻醉剂实时呼吸。 可以通过改进的传感器配置在不同入口条件下通过差压流量计监测呼吸流量,从而最小化气道内的相位滞后和死区。 可以通过发光淬灭技术监测分子氧浓度。 红外吸收技术可用于监测一种或多种CO 2,N 2 O和麻醉剂。
摘要:
Methods for estimating the volume of the carbon dioxide stores of an individual's respiratory tract include determining a carbon dioxide store volume at which a correlation between corresponding signals of carbon dioxide elimination and an indicator of the content of carbon dioxide in blood of the individual is optimized. The estimate of the volume of carbon dioxide stores, which comprises a model of the respiratory tract, or lungs, of the individual, may be used as a transformation to improve the accuracy of one or both of the carbon dioxide elimination and carbon dioxide content signals. Transformation, or filtering, algorithms are also disclosed, as are systems in which the methods and algorithms may be used. The methods, algorithms, and systems may be used to accurately and noninvasively determine one or both of the pulmonary capillary blood flow and cardiac output of the individual.
摘要:
Methods for noninvasively determining a pulmonary capillary blood flow or a cardiac output of a subject include determining data of the amount of gas exchanged between blood and gas in lungs of the subject, as well as data of an indicator of the content of the gas in blood of the subject. Such a determination may be made during two or more different states of ventilation. A geometric relationship is identified between data points, with any data points outlying the geometric relationship being disregarded. The remaining data points may be used to estimate or calculate a measure of pulmonary capillary blood flow or cardiac output. Systems that include elements that are configured to effect such methods are also disclosed.
摘要:
Methods for noninvasively measuring, or estimating, functional residual capacity or effective lung volume include obtaining carbon dioxide and flow measurements at or near the mouth of a subject. Such measurements are obtained during baseline breathing and during and shortly after inducement of a change in the subject's effective ventilation. The obtained measurements are evaluated to determine the amount of time required for exhaled carbon dioxide levels to return to normal—effectively an evaluation of carbon dioxide “washout” from the subject's lungs. Conversely, carbon dioxide and flow measurements may be evaluated to determine the amount of time it takes carbon dioxide to “wash in,” or reach peak levels within, the lungs of the subject following the change in the subject's effective ventilation. Apparatus for effective such methods are also disclosed.
摘要:
A method and device for indirect, quantitative estimation of cardiac output utilizing invasive, indirect techniques. The method of practice includes (i) generating a sequence of signals which are quantitatively dependent upon cardiac output, (ii) transmitting and processing the signals within a computer system and associated neural network capable of generating a single output signal for the combined input signals, (iii) directly determining an actual value for the parameter concurrent with the invasive generation of signals of the previous steps, (iv) applying weighting factors within the neural network at interconnecting nodes to force the output signal of the neural network to match the known value of the parameter as determined invasively, (v) recording the input signals, weighting factors and known value as training data within memory of the computer, and (vi) repeating the previous steps to develop sufficient training data to enable the neural network to accurately estimate parameter value upon future receipt of on-line input signals. Procedures are also described for preclassification of signals and artifact rejection. Following training of the neural network, further direct measurement is unnecessary and the system is ready for diagnostic application and invasive estimation of parameter values.
摘要:
An apparatus for reversing inhaled anesthesia, which is configured to be positioned along a breathing circuit or anesthesia delivery circuit, includes a filter for removing one or more anesthetic agents from gases passing therethrough, as well as a component for elevating CO2 levels in gases that are to be inhaled by an individual. The apparatus is configured to be positioned between a Y-connector of the breathing circuit and the portion of the breathing circuit that interfaces with the individual. The CO2 level-elevating component facilitates an increase in the ventilation of the individual without resulting in a significant decrease in the individual's PaCO2 level and, thus, a decrease in the rate at which blood flows through the individual's brain. A method of reversing the effects of inhaled anesthesia includes increasing the rate of ventilation of an anesthetized individual while causing the individual to inhale gases with elevated amounts of CO2 and while filtering anesthetic agents from such gases.
摘要翻译:用于反转吸入麻醉的装置,其被配置为沿着呼吸回路或麻醉输送回路定位,包括用于从通过其中的气体中去除一种或多种麻醉剂的过滤器,以及用于将CO 2升高的部件, / SUB>被个人吸入的气体中的水平。 该装置构造成位于呼吸回路的Y形连接器和与个体接触的部分呼吸回路之间。 CO 2升级组件有助于个体的通气量的增加,而不会导致个体的P <! - SIPO
摘要:
A system for sensing respiratory pressure includes a portable pressure transducer configured to be carried by or proximate to a respiratory conduit, such as a breathing circuit or a nasal canula. The portable pressure transducer may removably couple with a pneumotach, in the form of an airway adapter, disposed along the respiratory conduit. The pneumotach may include two pressure ports positioned at opposite sides of an obstruction, which partially blocks flow through a primary conduit of the pneumotach. Corresponding sample conduits of the portable pressure transducer removably couple with the pressure ports. The pressure ports may have sealing elements which are configured to seal against piercing members of the sample conduits upon introduction of the piercing members therethrough. Upon removal of the piercing members, the sealing elements substantially reseal. Methods for using the system are also disclosed.