초록 ▼

Metabolic gas monitoring apparatus and methods for measuring the metabolic rate in patients. The apparatus includes separate inlets for a calibration gas, inspired gas, and expired gas, and means for alternately introducing each gaseous sample into a thermoelectric cooler. The cooler is configured w

Metabolic gas monitoring apparatus and methods for measuring the metabolic rate in patients. The apparatus includes separate inlets for a calibration gas, inspired gas, and expired gas, and means for alternately introducing each gaseous sample into a thermoelectric cooler. The cooler is configured with relatively narrow passageways so as to contain a minimal amount of gaseous volume therein and thus provides for a more dynamic response time and for more accurate measurements. The apparatus further includes a carbon dioxide sensor and an oxygen sensor for measuring the concentration of carbon dioxide and oxygen, respectively, in the gaseous samples, and a microprocessor for comparing the measured concentrations of carbon dioxide and oxygen in the inspired gas and expired gas and for calculating the metabolic rate. Preferably, the oxygen sensor has a zirconium oxide differential electrode and a substantially equal pressure is maintained in a sample chamber and a reference chamber of the oxygen sensor.

대표청구항 ▼

An apparatus for measuring the metabolic rate of a patient, comprising: (a) a first inlet conduit for receiving expired gas from the respiratory system of a patient; (b) a second inlet conduit for receiving gas as inspired by the patient; (c) a third inlet conduit for receiving a calibration gas; (d

An apparatus for measuring the metabolic rate of a patient, comprising: (a) a first inlet conduit for receiving expired gas from the respiratory system of a patient; (b) a second inlet conduit for receiving gas as inspired by the patient; (c) a third inlet conduit for receiving a calibration gas; (d) an outlet conduit; (e) regulating means, positioned between said inlet conduits and said outlet conduit, for alternately regulating a continuous flow through said outlet conduit of one of said expired gas from the first inlet conduit, inspired gas from the second inlet conduit, or calibration gas from the third inlet conduit, said regulating means thereby serving to alternately allow passage of one gas at a time through said outlet conduit; (f) a cooler for cooling gas passing therethrough, said cooler being in gaseous communication with said outlet conduit so as to be positioned on the output side of said regulating means and said cooler serving to remove water from or add water vapor to the gas continuously flowing from said regulating means as needed to approximately equalize the water vapor pressure of each gas flowing through said cooler; (g) first sensing means in communication with the cooler for measuring the amount of carbon dioxide in a gaseous sample; (h) second sensing means in communication with the cooler for measuring the amount of oxygen in a gaseous sample; and (i) means for comparing the amounts of carbon dioxide and oxygen in one gaseous sample with those in another gaseous sample.