Indirect calorimetry system

• US 20020077765A1
• Filed: 10/01/2001
• Published: 06/20/2002
• Est. Priority Date: 09/29/2000
• Status: Active Grant

• Current Assignee: Microlife Medical Home Solutions Inc.
• Original Assignee: HealtheTech, Inc.
• Inventors: Mault, James R.
• Granted Patent: US 6,620,106 B2
• Time in Patent Office: Days
• US Class Current: 702/127
• CPC Class Codes: A61B 5/083 Measuring rate of metabolism by using breath test, e.g. measuring rate of oxygen consumption
• CPC Class Codes: A61B 5/097 Devices for facilitating collection of breath or for directing breath into or through measuring devices
• CPC Class Codes: A61B 5/411 Detecting or monitoring allergy or intolerance reactions to an allergenic agent or substance
• CPC Class Codes: G01N 33/497 of gaseous biological material, e.g. breath

Abstract

An indirect calorimetry system includes transducers sensitive to expired airflow that are enclosed within a calorimeter housing, and a microprocessor in communication with the transducers for calculating expiration characteristics. A graphical display displays the expiration characteristics. A communication link transmits expiration characteristics to external devices such as a computer, communication network, or PDA.

Claims

1. An indirect calorimetry system comprising:

a plurality of transducers sensitive to expired airflow;

a calorimeter housing enclosing the plurality of transducers;

a microprocessor in communication with the plurality of transducers for calculating expiration characteristics; and

a graphical display displaying the expiration characteristics.

2. The system of claim 1 wherein said microprocessor and said graphical display are attached to said calorimeter housing and said housing is handheld.

3. The system of claim 1 wherein said microprocessor is within a personal computer.

4. The system of claim 3 wherein said computer comprises software requiring log in prior to calculating expiration characteristics.

5. The system of claim 1 further comprising an oxygen sensor enclosed within said calorimeter housing.

6. The system of claim 1 further comprising a time-stamp circuit in communication with said microprocessor.

7. The system of claim 1 further comprising a nitric oxide sensor enclosed within said calorimeter housing.

8. The system of claim 1 further comprising a carbon dioxide sensor enclosed within said calorimeter housing.

9. The system of claim 1 further comprising a ventilator under feedback control based upon the expiration characteristics.

10. The system of claim 1 further comprising an intravenous pumping device under feedback control based upon the expiration characteristics.

11. The system of claim 1 further comprising a disposable mask intermediate between a subject and the plurality of transducers.

13. The system of claim 12 wherein said microprocessor and said graphical display are attached to said calorimeter housing and said housing is handheld.

14. The system of claim 12 wherein said microprocessor is within a personal computer.

15. The system of claim 14 wherein said computer comprises software requiring log in prior to calculating expiration characteristics.

16. The system of claim 12 further comprising an oxygen sensor enclosed within said calorimeter housing.

17. The system of claim 12 further comprising a time-stamp circuit in communication with said microprocessor.

18. The system of claim 12 further comprising a nitric oxide sensor enclosed within said calorimeter housing.

19. The system of claim 12 further comprising a carbon dioxide sensor enclosed within said calorimeter housing.

20. The system of claim 12 further comprising a ventilator under feedback control based upon the expiration characteristics.

21. The system of claim 12 further comprising an intravenous pumping device under feedback control based upon the expiration characteristics.

22. The system of claim 12 further comprising a disposable mask intermediate between a subject and the plurality of transducers.

24. The process of claim 23 further comprising providing feedback control to a device selected from the group consisting of:

a ventilator and an intravenous pump.

25. The process of claim 23 further comprising the step of communicating the expiration flow data to a device selected from the group consisting of:

a computer, a communication network and a PDA.

12. An indirect calorimetry system comprising:

a plurality of transducers sensitive to expired airflow;

a calorimeter housing enclosing the plurality of transducers;

a microprocessor in communication with the plurality of transducers for calculating expiration characteristics; and

a communications link to a device selected from the group consisting of;

a computer, a communication network, and a PDA.

23. A process for monitoring physiological gas exchange associated with respiration comprising the steps of:

expiring into an indirect calorimeter for a period of time;

measuring expiration flow with a plurality of transducers;

time stamping the measurement of expiration flow; and

displaying the expiration flow data as a function of the period of time.