METHOD AND APPARATUS FOR CO2 EVALUATION

• US 20110082357A1
• Filed: 05/27/2009
• Published: 04/07/2011
• Est. Priority Date: 05/28/2008
• Status: Abandoned Application

• Current Assignee: Neetour Medical Ltd.
• Original Assignee: Neetour Medical Ltd.
• Inventors: Hornick, Ofer
• Application Number:
  US12/993,588
• Publication Number:
  US 20110082357A1
• Time in Patent Office: Days
• US Class Current: 600/364
• CPC Class Codes: A61B 5/02 Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
• CPC Class Codes: A61B 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/0261 using optical means, e.g. infrared light
• CPC Class Codes: A61B 5/053 Measuring electrical impedance or conductance of a portion of the body
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• CPC Class Codes: A61B 5/4035 Evaluating the autonomic nervous system
• CPC Class Codes: A61B 5/7239 using differentiation including higher order derivatives

Abstract

A method for evaluating CO₂ level in the blood of a patient, comprising detecting in the patient'"'"'s body at least one haemodynamic signal from at least one tissue or part thereof, processing the at least one haemodynamic signal to derive a value related to the CO₂ level of the patient and determining an evaluation of CO₂ level of the patient based on a relation of the derived value to the CO₂ level of the patient, and an apparatus to carry out the same.

Claims

1. A method for evaluating CO₂ level in the blood of a patient, comprising:

(a) detecting from the patient'"'"'s body at least one haemodynamic signal from at least one tissue or part thereof;

(b) processing the at least one haemodynamic signal to derive a value related to the CO₂ level in the blood of the patient; and

(c) determining an evaluation of CO₂ level of the patient based on a relation of the derived value to CO₂ level in the blood of the patient.

2. The method according to claim 1, wherein detecting is performed non-invasively.

3. The method according to claim 1, wherein the at least one haemodynamic signal from at least one tissue or part thereof constitutes one signal from one tissue or part thereof.

4. The method according to claim 1, wherein the at least one haemodynamic signal from at least one tissue or part thereof constitutes a plurality of signals from a plurality of similar tissues or parts thereof.

5. The method according to claim 4, wherein the plurality of signals are detected simultaneously.

6. The method according to claim 4, wherein the similar tissues are disjoint skin regions.

7. The method according to claim 1, wherein the at least one haemodynamic signal from at least one tissue or part thereof constitutes a plurality of signals from one tissue or part thereof.

8. The method according to claim 7, wherein the plurality of signals are detected simultaneously.

9. The method according to claim 7, wherein the one tissue or part thereof is a skin region.

10. The method according to claim 1, wherein the at least one haemodynamic signal from at least one tissue or part thereof constitutes a plurality of signals from a plurality of different tissues or parts thereof.

11. The method according to claim 10, wherein the plurality of signals are detected simultaneously.

12. The method according to claim 10, wherein the plurality of different tissues comprises at least one tissue selected from skin, muscle or brain.

13. The method according to claim 10, wherein the plurality of different tissues comprises at least two tissues selected from skin, muscle or brain.

14. The method according to claim 1, wherein processing comprises identifying a region of the at least one signal, or a derivative thereof, by which a value functionally related to CO₂ level of the patient is derived.

15. The method according to claim 14, wherein identifying a region comprises analyzing a temporal derivative, or a combination thereof, of the at least one signal or a derivative thereof.

16. The method according to claim 14, wherein a value functionally related to CO₂ level of the patient is derived by integrating the temporal derivative, or a combination thereof, about the region.

17. The method according to claim 14, wherein the value functionally related to CO₂ level of the patient is linearly related to CO₂ level of the patient.

18. The method according to claim 1, wherein processing comprises:

(a) defining a model of a haemodynamic parameter based on a plurality of signals from a plurality of different tissues or parts thereof; and

(b) substituting in the model at least one separately acquired haemodynamic parameter thereby deriving a value related to the CO₂ level of the patient.

19. The method according to claim 1, wherein the value related to the CO₂ level of the patient constitutes the evaluation of CO₂ level of the patient.

20. An apparatus for evaluating CO₂ level in the blood of a patient, comprising:

(a) at least one detector on the patient'"'"'s body for detecting at least one haemodynamic signal from an at least one tissue or part thereof; and

(b) a processor and a program for deriving an evaluation of the CO₂ level of the patient based on the at least one haemodynamic signal.

21. The apparatus according to claim 20, further comprising an apparatus for providing at least the evaluation of the CO₂ level in the blood of the patient.

22. The apparatus according to claim 20, wherein the evaluation of the CO₂ level is provided continuously in real-time.

23. The apparatus according to claim 20, wherein the at least one detector is non-invasive.

24. The apparatus according to claim 20, wherein the apparatus is sufficiently small and lightweight for wearing by the patient.

25. The apparatus according to claim 20, wherein the apparatus is sufficiently mobile to be worn by an ambulatory patient.

26. (canceled)