Blood flow oxygen measurement system and method

• US 7,338,447 B2
• Filed: 05/05/2003
• Issued: 03/04/2008
• Est. Priority Date: 05/06/2002
• Status: Expired due to Fees

• Current Assignee: Uscom Ltd.
• Original Assignee: Uscom Pty Limited
• Inventors: Phillips, Robert Allan
• Primary Examiner(s): Jaworski; Francis J.
• Application Number:
  US10/513,632
• Publication Number:
  US 20050187469A1
• Time in Patent Office: 1,765 Days
• Field of Search: 600437-438, 600453-457, 600/459, 600/465, 600/468, 600323-324, 600/479, 600/483, 600500-502, 600504-507
• US Class Current: 600/438
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters
• CPC Class Codes: A61B 8/06 Measuring blood flow measuring volume flow in general G01F, e.g. G01F1/66, G01F1/72; measuring speed of fluids in general G01P5/00
• CPC Class Codes: A61B 8/4281 characterised by sound-transmitting media or devices for coupling the transducer to the tissue

Abstract

An apparatus for measuring physiologic tissues perfusion information including: a first device producing a first output indicative of blood flow of a patient; a second device producing a second output indicative of oxygen content of the blood; and a processor combining said first and said second outputs to produce a third output indicative of tissue perefusion.

Claims

1. An apparatus for measuring physiologic tissue perfusion information including:

a first device utilizing a CW Doppler monitoring method to image cardiac output from the heart to produce a first output indicative of real time blood flow of a patient;

a second device producing a second output indicative of oxygen content of the blood; and

a processor combining said first and said second outputs to produce a third output indicative of tissue perfusion.

2. An apparatus according to claim 1 wherein said second device uses oximetry to measure oxygen content.

3. An apparatus according to claim 1 wherein said third output is indicative of at least one of percent distance stroke saturation, percent minute distance saturation output, percent stroke volume saturation stroke volume and percent output saturation output.

4. An apparatus according to claim 1 wherein said apparatus combines intra cardiac or aortic blood flow with peripheral oximetry.

5. A method of measuring physiologic tissue perfusion information including obtaining a measurement of blood flow of a patient utilizing a CW Doppler monitoring method to image cardiac output from the heart and a measurement of real time blood oxygen content, and combining said measurements to produce an output indicative of tissue perfusion.

6. A method of creating a tissue perfusion index including:

(a) obtaining a measurement of blood flow utilizing a CW Doppler monitoring method to image cardiac output from the heart and a measurement of real time blood oxygen content from a patient;

(b) combining said measurements to calculate a parameter indicative of tissue perfusion in said patient;

(c) repeating steps (a) and (b) on a plurality of patients to obtain a set of calculations of said parameter for said plurality of patients;

(d) processing the set of calculated parameters to obtain a statistically averaged index of said parameter for a population.

10. A method according to claim 6 wherein said parameter indicative of tissue pervasion is at least one of percent distance stroke saturation, percent minute distance saturation output, percent stroke volume saturation stroke volume and percent output saturation output.

11. A method according to claim 6 wherein said measurement of blood flow comprises a transcutaneous measure of the volume of blood flow out of a patient'"'"'s heart.

7. A method of creating a tissue perfusion index for healthy population including:

(a) obtaining a measurement of blood flow utilizing a CW Doppler monitoring method to image cardiac output from the heart and a measurement of real time blood oxygen content from a healthy patient;

(b) combining said measurements to calculate a parameter indicative of tissue perfusion in said healthy patient;

(c) repeating steps (a) and (b) on a plurality of healthy patients to obtain a set of calculations of said parameter for said plurality of patients;

(d) processing the set of calculated parameters to obtain a statistically averaged index of said parameter for a healthy population.

12. A method according to claim 7 wherein said parameter indicative of tissue perfusion is at least one of percent distance stroke saturation, percent minute distance saturation output, percent stroke volume saturation stroke volume and percent output saturation output.

15. A method according to claim 7 wherein said measurement of blood flow comprises a transcutaneous measure of the volume of blood flow out of a patient'"'"'s heart.

8. A method of creating a tissue perfusion index for a population with a known condition including:

(a) obtaining a measurement of blood flow utilizing a CW Doppler monitoring method to image cardiac output from the heart and a measurement of real time blood oxygen content from a patient with said known condition;

(b) combining said measurements to calculate a parameter indicative of tissue perfusion in said patient;

(c) repeating steps (a) and (b) on a plurality of patients with said known condition to obtain a set of calculations of said parameter for said plurality of patients;

(d) processing the set of calculated parameters to obtain a statistically averaged index of said parameter for a population with said known condition.

13. A method according to claim 8 wherein said parameter indicative of tissue perfusion is at least one of percent distance stroke saturation, percent minute distance saturation output, percent stroke volume saturation stroke volume and percent output saturation output.

16. A method according to claim 8 wherein said measurement of blood flow comprises a transcutaneous measure of the volume of blood flow out of a patient'"'"'s heart.

9. A method of diagnosing a condition in a patient including

(a) obtaining a measurement of blood flow utilizing a CW Doppler monitoring method to image cardiac output from the heart to produce and a measurement of real time blood oxygen content from a patient;

(b) combining said measurements to calculate a parameter indicative of tissue perfusion in said patient;

(c) comparing said calculated parameter with a statistically averaged index of said parameter to determine the extent to which said condition exists within said patient.

14. A method according to claim 9 wherein said parameter indicative of tissue perfusion is at least one of percent distance stroke saturation percent minute distance saturation output, percent stroke volume saturation stroke volume and percent output saturation output.

17. A method according to claim 9 wherein said measurement of blood flow comprises a transcutaneous measure of the volume of blood flow out of a patient'"'"'s heart.