Non-invasive device and method for the diagnosis of pulmonary vascular occlusions
The invention involves a device and method for ascertaining the functioning of the respiratory system and determining the cause of abnormal respiratory function. The device comprises an apparatus for measuring the flow of air from a patient's breadth and determining the concentration of gases contained therein via real-time spectrometry. From this data, a processor computes the ratio of detected gases relative to each other and as a function of expired volume and plots the calculations on a display screen. Based on various plots, a physician can more easily estimate the probability of a number of pulmonary diseases and afflictions, such pulmonary embolism, emphysema, congestive heart failure, infection, and related problems.
1. A system for non-invasively diagnosing abnormal respiratory function, comprising:
a patient breathing tube;
a flow meter connected to said tube;
a spectrometer interconnected to and in fluid communication with said tube, wherein said spectrometer is adapted to detect the concentration of gases present in said tube; and
data processing means interconnected to said flow meter and said spectrometer, wherein said data processing means is programmed to calculate and display at least one gas concentration ratio selected from the group consisting of the ratio of NO relative to the concentration of CO, the ratio of CO 2 to O 2 relative to the ratio of NO to CO, the ratio of NO to CO relative to expired volume, the ratio of CO 2 to O 2 relative to the ratio of CO 2 to O 2 relative to expired volume, and the ratio of CO 2 to O 2 simultaneously with a plot of NO relative to expired volume.
2. The system of claim 1 , wherein said gas concentration ratio is the concentration of CO 2 relative to the concentration of O 2 .
3. The system of claim 1 , wherein said gas concentration ratio is the concentration of NO relative to the concentration of CO.
4. The system of claim 1 , wherein said gas concentration ratio is the ratio of CO 2 to O 2 relative to the ratio of NO to CO.
5. The system of claim 1 , wherein said gas concentration ratio is the ratio of NO to CO relative to expired volume.
6. The system of claim 1 , wherein said gas concentration ratio is the ratio of CO 2 to O 2 relative to NO.
7. The system of claim 1 , wherein said gas concentration ratio is the ratio of CO 2 to O 2 simultaneously with a plot of NO relative to expired volume.
8. The system of claim 1 , wherein said spectrometer comprises a laser diode spectrometer remotely interconnected to and in fluid communication with said tube via a port in said patient breathing tube.
9. The system of claim 8 , further comprising a vacuum pump interconnected to said spectrometer and said port.
10. The system of claim 9 , wherein said vacuum pump operates at a rate of between about 10 to 100 milliliters per minute.
11. The system of claim 8 , wherein said laser diode spectrometer is adapted to measure analyte concentrations of NO, CO, CO 2 , and O 2 .
12. The system of claim 8 , wherein said laser diode spectrometer simultaneously measures CO 2 , O 2 , NO and CO.
13. The system of claim 8 , wherein said laser spectrometer alternates between the measurement of any combination of CO 2 , O 2 , NO, and CO at a rate of at least twenty times per second for each such molecule.
14. The system of claim 8 , wherein said laser spectrometer comprises a monochromatic light source from at least one tunable diode laser operating in a ring-down cavity mode with two or more mirror to increase apparent path length.
15. The system of claim 8 , wherein said tube further includes a coupling for attachment to standard ventilator circuits.
16. The system of claim 8 , wherein said tube further includes a coupling for attachment to a patient mouthpiece.
17. The system of claim 8 , wherein said flow meter is a sensor selected from the group consisting of thermal flow sensors, pressure differential sensors, and ultrasonic flow sensors.
18. A system for non-invasively diagnosing abnormal respiratory function, comprising:
a patient breathing tube;
a flow meter connected to said tube;
a spectrometer interconnected to and in fluid communication with said tube, wherein said spectrometer is adapted to detect the concentration of gases present in said tube; and
data processing means interconnected to said flow meter and said spectrometer, wherein said data processing means is programmed to phase align the concentrations of said gases to allow for accurate plotting of ratios and concentrations as a function of expired volume.
19. A system for non-invasively diagnosing abnormal respiratory function, comprising:
a patient breathing tube;
a flow meter connected to said tube;
a spectrometer interconnected to and in fluid communication with said tube, wherein said spectrometer is adapted to detect the concentration of gasses present in the tube;
and
data processing means interconnected to said flow meter and said spectrometer, wherein said data processing means is programmed to calculate and display the ratio of CO2 to O2 relative to expired volume.