摘要:
A method of controlling PCO2 in a patient at a predetermined desired level(s) comprising a breathing circuit which is capable of organizing exhaled gas so as to be preferentially inhaled during re-breathing when necessary by providing alveolar gas for re-breathing in preference to dead space gas.
摘要:
An apparatus for inducing hypoxia in a subject is provided. The apparatus includes a breathing port, an inspiratory reservoir, means for introducing oxygen into the apparatus, means for controlling the flow rate of entry of oxygen into the apparatus at a rate below the subject's metabolic requirements, an expiratory reservoir having a vent, Sequential Gas Delivery means, and means for removing CO2 from the circuit. The Sequential Gas Delivery means are for directing the gases such that upon expiration, the subject expires into the expiratory reservoir, and, upon inspiration, subject inspires first from the inspiratory reservoir, and, on any breath, once said inspiratory reservoir is depleted, gas for the balance of that inspiration is delivered from the expiratory reservoir
摘要:
A portable isocapnia circuit and an isocapnia method. A breathing port of the circuit allows a subject to inhale and exhale. Connected to the breathing port, a bifurcate conduit has a first conduit branch and a second conduit branch. The first conduit branch has an atmospheric air inlet, from which the atmospheric air is provided for inhalation, an inspiratory check valve to allow a one-way flow of the atmospheric air, and an atmospheric air aspirator. The second conduit branch has a one-way expiratory check valve and a expiratory gas reservoir. A one-way check valve is used to interconnect the first and second conduit branch, from which the expiratory gas stored in the expiratory gas reservoir flows to the first conduit branch to mix with the atmospheric air when the minute ventilation exceeds the atmospheric air.
摘要:
A method to maintain isocapnia for a subject. A fresh gas is provided to the subject when the subject breathes at a rate less than or equal to the fresh gas flowing to the subject. The fresh gas flow equal to a baseline minute ventilation minus a dead space gas ventilation of the subject contains a physiological insignificant amount of CO2. An additional reserve gas is provided to the subject when the subject breathes at a rate more than the fresh gas flowing to the subject. The reserve gas has a partial pressure of carbon dioxide equal to an arterial partial pressure of carbon dioxide of the subject. A breathing circuit is applied to the method to maintain isocapnia for a subject. The breathing circuit has an exit port, a non-rebreathing valve, a source of fresh gas, a fresh gas reservoir and a reserve gas supply.
摘要:
A method to maintain isocapnia for a subject. A fresh gas is provided to the subject when the subject breathes at a rate less than or equal to the fresh gas flowing to the subject. The fresh gas flow equal to a baseline minute ventilation minus a dead space gas ventilation of the subject contains a physiological insignificant amount of CO2. An additional reserve gas is provided to the subject when the subject breathes at a rate more than the fresh gas flowing to the subject. The reserve gas has a partial pressure of carbon dioxide equal to an arterial partial pressure of carbon dioxide of the subject. A breathing circuit is applied to the method to maintain isocapnia for a subject. The breathing circuit has an exit port, a non-rebreathing valve, a source of fresh gas, a fresh gas reservoir and a reserve gas supply.
摘要:
A method and apparatus for evaluating the relative contribution of the diaphragm versus other thoracic muscles to breathing by obtaining measurements of parameters that correlate with changes in thoracic cavity and intra-abdominal cavity pressures over identical time increments and organizing the measurement data in manner that reveals whether the pressures changes are characteristic of the pattern of contemporaneous pressure changes in those cavities that accompany contraction and/or relaxation of the diaphragm muscles or whether the pressure changes are characteristic of the pattern of contemporaneous pressure changes in those cavities that accompany contraction and/or relaxation of the intercostal muscles.
摘要:
An apparatus to measure cardiac output (Q) and other parameters such as alveolar ventilation (VA), minute CO2 elimination from the lung (VCO2), minute oxygen consumption (VO2), oxygenated mixed venous partial pressure of CO2, (PvCO2-oxy), true mixed venous partial pressure of CO2(PvCO2), PaCO2, mixed venous oxygen saturation (SvO2), pulmonary shunt, and anatomical dead space, consisting of: a) a breathing circuit with characteristics that: i. on exhalation, exhaled gas is kept substantially separate from inhaled gas; ii. on inhalation, when VE is greater than FGS flow, the subject inhales FGS first and then inhales a gas that is substantially SGS, for the balance of inhalation; b) gas sensor means for monitoring gas concentrations at the patient-circuit interface c) a first gas set (FGS), and a second gas set (SGS), said second gas set which may comprise previously exhaled gases or exogenous gases or both d) a gas flow control means for controlling the rate of FGS flow into the breathing circuit e) means to identify phase of breathing, said means may consist of pressure sensors or analysis of signal generated by gas sensors or other means known to those skilled in the art; f) machine intelligence consisting of a computer or logic circuit capable of controlling the gas flow control means, receiving the output of the gas sensor means and means to identify phase of breathing, and performing the calculations for measuring cardiac output and other parameters as outlined in the disclosure.
摘要:
A method of calculating the flux of any gas (x) in a CBC circuit for a ventilated or a spontaneous breathing subject, for example said gas(x) being; a) an anesthetic such as but limited to; i)N2O; ii) sevoflurane; iii) isoflurane; iv) halothane; v) desflurame; or the like b) Oxygen; c) Carbon dioxide; or the like utilizing the following relationships; Flux of gas(x)=SGF (FSX−FEX) wherein SGF=Source of gas flow into the breathing circuit (CBC circuit) in liters/minute as read from the gas flow meter as set by the anesthesiologist; FSX=Fractional concentration of gas X in the source gas (which is set by the anesthesiologist); FEX=Fractional concentration of gas X in the end expired gas as determined by a portable gas analyzer, or the like.
摘要:
A process for determining gas(x) consumption, wherein said gas(x) is selected from; a) an anesthetic such as but not limited to; i) N2O; ii) sevoflurane; iii) isoflurane; iv) halothane; v) desflurame; or the like b) Oxygen (O2).
摘要:
An apparatus to measure cardiac output (Q) and other parameters such as alveolar ventilation (VA), minute CO2 elimination from the lung (VCO2 ), minute oxygen consumption (VO2), oxygenated mixed venous partial pressure of CO2, (PvCO2-oxy), true mixed venous partial pressure of CO2(PvCO2), PaCO2, mixed venous oxygen saturation (SvO2), pulmonary shunt, and anatomical dead space, consisting of: a) a breathing circuit with characteristics that: i. on exhalation, exhaled gas is kept substantially separate from inhaled gas; ii. oninhalation, when VE is greater than FGS flow, the subject inhales FGS first and then inhales a gas that is substantially SGS, for the balance of inhalation; b) gas sensor means for monitoring gas concentrations at the patient-circuit interface c) a first gas set (FGS), and a second gas set (SGS), said second gas set which may comprise previously exhaled gases or exogenous gases or both d) a gas flow control means for controlling the rate of FGS flow into the breathing circuit e) means to identify phase of breathing, said means may consist of pressure sensors or analysis of signal generated by gas sensors or other means known to those skilled in the art; f) machine intelligence consisting of a computer or logic circuit capable of controlling the gas flow control means, receiving the output of the gas sensor means and means to identify phased of breathing, and performing the calculations for measuring cardiac output and other parameters as outlined in the disclosure.
摘要翻译:一种用于测量心输出量(Q)和其它参数(例如肺泡通气(VA)),从肺部消除的微小CO 2(VCO 2)的装置,微量氧消耗( VO 2 2),CO 2氧合混合静脉分压,(PvCO 2 - 氧基),真正的混合静脉分压CO