Non-invasive, miniature, breath monitoring apparatus

• US 6,955,652 B1
• Filed: 05/09/2003
• Issued: 10/18/2005
• Est. Priority Date: 06/25/2001
• Status: Expired due to Term

• Current Assignee: Oak Crest Institute Of Science
• Original Assignee: Oak Crest Institute Of Science
• Inventors: Lord, Harry C., Baum, Marc M.
• Primary Examiner(s): Nasser, Robert
• Assistant Examiner(s): Mallari, Patricia
• Application Number:
  US10/435,095
• Time in Patent Office: 893 Days
• Field of Search: 128/203.12, 128/203.22, 12820418-20525, 128/200.24, 73/233, 600529-543
• US Class Current: 600/532
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/029 Measuring or recording blood output from the heart, e.g. minute volume A61B8/065 takes precedence
• CPC Class Codes: A61B 5/0813 Measurement of pulmonary parameters by tracers, e.g. radioactive tracers
• CPC Class Codes: A61B 5/083 Measuring rate of metabolism by using breath test, e.g. measuring rate of oxygen consumption
• CPC Class Codes: G01N 2021/3129 Determining multicomponents by multiwavelength light
• CPC Class Codes: G01N 2021/3137 with selection of wavelengths after the sample
• CPC Class Codes: G01N 2021/3166 using separate detectors and filters
• CPC Class Codes: G01N 2021/398 CO2 laser
• CPC Class Codes: G01N 21/05 Flow-through cuvettes G01N21/09 takes precedence; handling fluid samples G01N1/10
• CPC Class Codes: G01N 21/3504 for analysing gases, e.g. multi-gas analysis
• CPC Class Codes: G01N 33/497 of gaseous biological material, e.g. breath

Abstract

A rugged, miniature, spectroscopic gas analyzer apparatus for rapid, non-invasive, multi-component breath monitoring and analysis and subsequent determination of Q or other medical diagnostic applications. The system is comprised of one or more IR emitters focussed by optical elements through a low volume sample cell receiving a sample input of a patient'"'"'s breath for analysis. The patient either at rest or during exercise, inhales C₂H₂—SF₆ mixtures (balance of oxygen and nitrogen) which is subsequently monitored upon exhalation for CO₂, H₂O, C₂H₂, and SF₆ which can be employed to determine Q directly and accurately. Measurements are performed in real-time or via post-processing of stored original data. Due to its small size, ruggedness, and low power consumption, the monitor can conveniently be employed in the field or data can also be retrieved remotely using telemetry. The miniature analyzer operates on the principle of infrared absorption spectroscopy and allows very precise concentration measurements of the analytes of interest, without any bias or interference from other matrix components.

Claims

1. A breath monitoring apparatus for medical diagnostic analysis comprising:

a container having a mixture of gases, wherein said mixture comprises one of CO, N₂O or CH₄ balanced with nitrogen;

a collector adapted to connect a subject to said container for collecting a breath sample that includes said gas mixture;

a breathing tube connected to said collector, said breathing tube having a mouthpiece, said container of gases and a flow control valve between the tube and said container;

a sample cell connected to said collector for receiving said breath sample;

a radiation emitter for irradiating said sample cell;

a beamsplitter for splitting beams received from said radiation emitter after said beams pass through said sample cell;

a bandpass filter for filtering each of said split beams and isolating a particular spectral region; and

at least one detector for detecting said spectral region received from said bandpass filter and producing an electrical signal.

2. A breath monitoring apparatus for medical diagnostic analysis comprising:

a sample cell containing a breath sample collected from a subject;

a plurality of radiation emitters for irradiating said sample cell;

at least one beamsplitter for splitting beams from said radiation emitters after said beams pass through said sample cell;

a bandpass filter for filtering each of said split beams and isolating a particular spectral region; and

at least one detector for detecting said spectral region received from said bandpass filter and producing an electrical signal.

3. A breath monitoring apparatus for medical diagnostic analysis comprising:

a container having a mixture of gases;

a collector adapted to connect a subject to said container for collecting a breath sample that includes said gas mixture;

a sample cell connected to said collector for receiving said breath sample;

one or more radiation emitters for irradiating said sample cell;

a plurality of beamsplitters for splitting beams from said one or more radiation emitters after said beams pass through said sample cell;

one or more bandpass filters for filtering each of said split beams and isolating a particular spectral region; and

at least one detector for detecting said spectral region received from said one or more bandpass filters and producing an electrical signal.

4. A breath monitoring apparatus for medical diagnostic analysis comprising:

a container having a mixture of gases;

a collector for collecting a breath sample that includes said gas mixture;

a connector adapted to connect said collector to a subject;

a sample cell connected to said collector for receiving said breath sample;

a radiation emitter for irradiating said sample cell;

a beamsplitter for splitting beams from said radiation emitter after said beams pass through said sample cell;

a narrow bandpass optical filter for filtering each of said split beams and isolating between 1% and 5% of a central wavelength of a particular spectral region; and

at least one detector for detecting said spectral region received from said bandpass filter and producing an electrical signal.

5. A breath monitoring apparatus for medical diagnostic analysis comprising:

a container having a mixture of gases;

a collector adapted to connect a subject to said container for collecting a breath sample that includes said gas mixture;

a sample cell connected to said collector for receiving said breath sample;

a radiation emitter for irradiating said sample cell;

a beamsplitter for splitting beams from said radiation emitter after said beams pass through said sample cell;

a bandpass filter for filtering each of said split beams and isolating a particular spectral region;

at least one detector for detecting said spectral region received from said bandpass filter and producing an electrical signal; and

a gas filter correlation spectrometer for monitoring acetylene.