Non-invasive blood pressure sensing device and method using transducer with associate memory

• US 6,241,679 B1
• Filed: 05/24/1999
• Issued: 06/05/2001
• Est. Priority Date: 05/24/1999
• Status: Expired due to Fees

• Current Assignee: Medwave, Inc.
• Original Assignee: Medwave, Inc.
• Inventors: Curran, Timothy G.
• Primary Examiner(s): Nasser, Robert L.
• Application Number:
  US09/317,291
• Time in Patent Office: 743 Days
• Field of Search: 600/300, 600/485, 600/500-503, 600/504, 600/561, 600/529
• US Class Current: 600/485
• CPC Class Codes: A61B 2560/0406 specially shaped apparatus housings
• CPC Class Codes: A61B 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/02108 from analysis of pulse wave characteristics
• CPC Class Codes: A61B 5/681 Wristwatch-type devices

Abstract

The present invention is an improvement to a non-invasive blood pressure sensing device and method. The present invention is an improvement that includes a transducer with an associated memory or memories for storing data such as sensor characteristics and history information. In a preferred embodiment, the stored information includes transducer offsets and gains, date code, serial number, model type, usage counter, time stamp of the last test of the device, motor characteristics and one or more checksums. The stored data is used by the device for several purposes including calibration, generation of indications such as component expiration indications and test needed indications, automatic identification of appropriate algorithms for control and data manipulation, service and billing.

Claims

1. A non-invasive blood pressure measurement device for determining blood pressure of an artery, the device comprising:

a sensor which is adapted to be pressed against the artery to produce blood pressure signals;

a non-volatile memory carried by the sensor for storing data including sensor history information, the sensor history information including a stamp of a last test of the sensor;

means for determining whether the sensor should be tested based on the stamp of the last test of the sensor;

means for providing an indication that new testing should be performed;

means for performing a test of the sensor; and

means for displaying results of the test of the sensor.

2. The device of claim 1, wherein the stamp of a last test of the sensor includes a time and a date.

3. The device of claim 1, wherein the non-volatile memory also stores a sensor date code, and wherein the device updates sensor expiration data based on the sensor date code and displays the updated sensor expiration data.

4. A non-invasive blood pressure measurement device for determining blood pressure of an artery, the device comprising:

a sensor which is adapted to be pressed against the artery to produce blood pressure signals; and

a non-volatile memory carried by the sensor for storing data including sensor history information including a stamp of a last test of the sensor;

wherein the device identifies and uses appropriate device control algorithms based upon data retrieved from the non-volatile memory.

8. The system of claim 4, wherein the drive assembly information includes a time stamp of a last test of the drive assembly.

9. The system of claim 8, wherein the time stamp includes a time and a date.

10. The system of claim 4, wherein the sensor history information includes a time stamp of a last test of the sensor.

11. The system of claim 10, wherein the time stamp includes a time and a date.

12. The system of claim 4, wherein the instrument reads and updates the sensor history information and drive assembly information.

13. The system of claim 4, wherein the instrument reads data from the first and the second non-volatile memories to determine when the sensor and the drive assembly were last tested.

14. The system of claim 13, wherein the instrument provides a notification when the sensor and the drive assembly should be tested.

15. The system of claim 4, wherein the first non-volatile memory also stores a sensor date code, and wherein the instrument updates sensor expiration data based on the sensor date code and displays the updated sensor expiration data.

16. The system of claim 15, wherein the sensor date code represents a sensor initialization date from which a sensor expiration date is determined.

17. The system of claim 4, wherein the first non-volatile memory also stores model type data, and wherein the system identifies and uses appropriate control algorithms based upon data retrieved from the first non-volatile memory.

18. The system of claim 4, wherein the first non-volatile memory also stores model type data, and wherein the system identifies and uses appropriate data manipulation algorithms based upon data retrieved from the first non-volatile memory.

19. The system of claim 4, wherein the first and the second non-volatile memories also store a checksum based on data stored in the non-volatile memories.

5. A non-invasive blood pressure measurement device for determining blood pressure of an artery, the device comprising:

a sensor which is adapted to be pressed against the artery to produce blood pressure signals; and

a non-volatile memory carried by the sensor for storing data including sensor history information involving a stamp of a last test of the sensor;

wherein the device identifies and uses appropriate data manipulation algorithms based upon data retrieved from the non-volatile memory.

6. A non-invasive blood pressure measurement device for determining blood pressure of an artery, the device comprising:

a sensor which is adapted to be pressed against the artery to produce blood pressure signals; and

a non-volatile memory carried by the sensor for storing data including sensor history information including a stamp of a last test of the sensor;

wherein the non-volatile memory also stores a checksum that is based on data stored in the non-volatile memory.

7. A non-invasive blood pressure measurement system for determining blood pressure of an artery, the system comprising:

a sensor which is adapted to be pressed against the artery to produce blood pressure signals;

a first non-volatile memory carried by the sensor for storing data including sensor history information;

an instrument connected to the sensor and the first non-volatile memory for providing blood pressure values based upon the blood pressure signals;

a wrist module attachable to a patient'"'"'s wrist and including a drive assembly connectable to the sensor for applying force to cause the sensor to be pressed against the patient'"'"'s wrist, the wrist module connected to the instrument, the drive assembly controlled by the instrument; and

a second non-volatile memory carried by the drive assembly for storing drive assembly information, the drive assembly information including data characterizing the drive assembly.