Access pressure ratio device and testing method

• US 7,597,666 B2
• Filed: 07/29/2002
• Issued: 10/06/2009
• Est. Priority Date: 07/30/2001
• Status: Active Grant

• Current Assignee: Henry Ford Health System
• Original Assignee: Henry Ford Health System
• Inventors: Yee, Jerry, Frinak, Stanley, Besarab, Anatole, Zasuwa, Gerard
• Primary Examiner(s): Mallari; Patricia C
• Application Number:
  US10/516,389
• Publication Number:
  US 20060272421A1
• Time in Patent Office: 2,626 Days
• Field of Search: 600/485, 600/481, 600/486, 604/4.01, 604/6.11, 604/6.14, 604/6.16, 604/65, 604/5.01, 604/19, 735/92, 210/739
• US Class Current: 600/485
• CPC Class Codes: A61B 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/411 Detecting or monitoring allergy or intolerance reactions to an allergenic agent or substance
• CPC Class Codes: A61B 5/413 Monitoring transplanted tissue or organ, e.g. for possible rejection reactions after a transplant
• CPC Class Codes: A61M 1/3639 Blood pressure control, pressure transducers specially adapted therefor
• CPC Class Codes: A61M 1/3641 Pressure isolators
• CPC Class Codes: A61M 1/3653 Interfaces between patient blood circulation and extra-corporal blood circuit
• CPC Class Codes: A61M 1/3656 Monitoring patency or flow at connection sites; Detecting disconnections
• CPC Class Codes: A61M 1/3659 Cannulae pertaining to extracorporeal circulation
• CPC Class Codes: A61M 1/3661 for haemodialysis
• CPC Class Codes: A61M 2205/3331 Pressure; Flow

Abstract

The present invention discloses a detection device for detecting irregular intravascular pressure, the device including an analyzer for automatically analyzing intravascular pressure upstream of the suspected location of irregular blood flow, and a comparing device that correlates the recorded intravascular pressure to a standard whereby variation in the intravascular pressure during multiple tests is indicative of irregular blood flow. Also disclosed is a system for providing a warning of potential health problems due to irregular blood flow, the system including a detecting device as set forth above and a communicating device operatively connected to the detecting device for communicating a warning when the device indicates an irregularity of intravascular pressure during at least two uses of the device.

Claims

1. A detection device for detecting intravascular pressure in a person, said device comprising:

analyzing means for automatically deriving venous access pressure (VAP) in proximity of a suspected location of a blood flow restriction and determining a ratio of VAP to mean arterial pressure, where analyzing means determines multiple VAP values over multiple time periods and determines multiple ratios, one for each VAP value, and

detecting means for comparing each ratio to a standard ratio, where the detecting means detects the blood flow restriction only when elevation of the ratio above the standard ratio over a series of consecutive comparisons is indicated.

2. The device according to claim 1, wherein said analyzing means includes a microprocessor.

3. A system for providing warning of potential health problems due to irregular intravascular pressure caused by blockage of the blood vessels in proximity of an extracorporeal blood access, said system comprising:

a detection device according to claim 1; and

communication means operably connected to said device for communicating a warning when said device detects the blood flow restriction.

4. The system according to claims 3, wherein said communication means is selected from the group consisting essentially of electronic communications, facsimile, telephone, cable modem, and T1 connection.

5. The device according to claim 1, wherein said device is a blood pressure detection device.

6. The device according to claim 1, wherein said blood flow restriction indicates a risk selected from the group consisting of potential access failure, heart attack, and stenosis.

7. The device according to claim 1, wherein the analyzing means derives the venous access pressure from a venous drip pressure measurement.

8. A method of detecting potentially compromised or restricted blood flow by:

calculating a ratio of venous access pressure to mean arterial pressure, where the venous access pressure is in proximity of a suspected location of the compromised or restricted blood flow;

using an analyzer, comparing the ratio to a standard;

repeating the calculating and comparing steps;

detecting restricted blood flow only when elevation of the ratio above the standard over a series of consecutive comparisons is indicated.

9. The method of claim 8, wherein said comparing step further includes automatically comparing the ratio to the standard.

10. The method of claim 9, wherein said automatically comparing step further includes automatically comparing the ratio to the standard using an algorithm.

11. The method of claim 8, wherein said calculating step further includes automatically calculating the ratio.

12. The method of claim 8, wherein said calculating step further includes automatically calculating the ratio during a procedure.