Method and system for monitoring the physiological condition of a patient

• US 5,964,720 A
• Filed: 11/26/1997
• Issued: 10/12/1999
• Est. Priority Date: 11/29/1996
• Status: Expired due to Term

• Current Assignee: Adaptivity Devices Limited
• Original Assignee: Adaptivity Devices Limited
• Inventors: Pelz, Shmuel
• Primary Examiner(s): O'Connor, Cary
• Assistant Examiner(s): MARMOR II, CHARLES ALAN
• Application Number:
  US08/979,938
• Time in Patent Office: 685 Days
• Field of Search: 600/500, 600/501, 600/527, 600/534, 600/595, 600/481, 600/483, 600/484
• US Class Current: 600/595
• CPC Class Codes: A61B 2562/0247 Pressure sensors
• CPC Class Codes: A61B 2562/043 in a linear array
• CPC Class Codes: A61B 5/0002 Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network A61B5/07 takes precedence; transmission systems for measured values G08C; transmission H04B; transmission of digital information H04L; wireless communication networks H04W
• CPC Class Codes: A61B 5/11 Measuring movement of the entire body or parts thereof, e.g. head or hand tremor, mobility of a limb for measuring pulse A61B5/02 ;A61B5/1038 takes precedence; motion detection to correct for motion artifacts in physiological signals A61B5/721
• CPC Class Codes: A61B 5/1102 Ballistocardiography
• CPC Class Codes: A61B 5/113 occurring during breathing
• CPC Class Codes: A61B 5/4818 Sleep apnoea
• CPC Class Codes: A61B 5/6887 mounted on external non-worn devices, e.g. non-medical devices
• CPC Class Codes: A61B 5/6892 Mats
• CPC Class Codes: A61B 5/7275 Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor

Abstract

A system for the monitoring of a patient'"'"'s physiological condition, including a measuring device for measuring the mechanical activity of a patient'"'"'s body, including a module for detecting mechanical vibrations and transmitting same to a sensing element for converting the mechanical movements into electric signals. A device for transmitting the electric signals for processing the electric signals and separating from them cardiac, respiration and body movement signals. A device for measuring the pulse wave propagation rate. A device for determining the characteristics and derived parameters of cardiac and respiratory cycles, as well as for storing and displaying the data. A comparator for comparing parameters of the data with predetermined parameters and a device for actuating an alarm signal when signals of the data exceed a preset range.

Claims

1. A system for monitoring of a patient'"'"'s physiological condition, comprising:

means for measuring the mechanical activity of a patient'"'"'s body, including at least one means for detecting mechanical vibrations and transmitting the same to one or more sensing elements for converting the mechanical vibrations into electric signals;

means for transmitting said electric signals;

means for processing said electric signals and separating therefrom cardiac, respiration and body movement signals;

means for determining the pulse wave propagation rate from said electric signals;

means for determining characteristics and parameters of cardiac and respiratory cycles, from said cardiac and respiration signals, respectively as well as for storing and displaying at least a portion of said characteristics and parameters;

means for comparing at least one of said determined parameters with a predetermined parameter; and

means for actuating an alarm signal when said at least one of said determined parameters exceeds a preset range.

2. The system according to claim 1, wherein said means for detecting mechanical vibrations and said sensing element are made as an integral unit.

3. The system according to claim 2, wherein said means for measuring the mechanical activity of a body comprises at least two sensors.

4. The system according to claim 3, wherein said sensors are secured to, or made integral with, a common means for detecting mechanical vibrations.

5. The system according to claim 2, wherein said means for detecting mechanical vibration is incorporated into a pen or any other hand tool.

6. The system according to claim 1, wherein said means for detecting mechanical vibration comprises a plate or strip-like member.

7. The system according to claim 6, wherein said plate or strip-like member consists of at least two parts connected by a flexible element.

8. The system according to claim 6, wherein said plate or strip-like member comprises at least one structural feature of a bed or an armchair.

9. The system according to claim 6, wherein said plate or strip-like member is incorporated into a piece of bedding.

10. The system according to claim 6, wherein said plate or strip-like member comprises a floor element.

11. The system according to claim 1, wherein said means for transmitting mechanical vibrations comprises a string.

12. The system according to claim 1, wherein said sensing element comprises a crystal.

13. The system according to claim 12, wherein said crystal is a piezoelectric crystal.

14. The system according to claim 1, wherein said sensing element comprises piezoelectric ceramics.

15. The system according to claim 1, wherein said sensing element comprises a piezoelectric film.

16. The system according to claim 1, wherein said means for signal processing, means for determining the rate of pulse wave propagation, means for determining characteristics and parameters of cardiac and respiratory cycles, means for storing and displaying the characteristics and parameters, means for comparing at least one determined parameter with a predetermined parameter and means for actuating an alarm signal, comprise one of a computer and a microprocessor.

17. The system according to claim 1, wherein said means for transmitting electric signals comprises a wire, radio or infrared communication device.

19. A method according to claim 1, further comprising the step of detecting and measuring signals associated with external vibrations and/or snoring.

20. A method according to claim 19, wherein the components known to be associated with external vibrations or snoring are measured by at least one additional measuring means.

18. A method of monitoring the physiological condition of a patient'"'"'s body, comprising the steps of:

obtaining signals representing the mechanical activity and movement of the body from two or more detecting and sensing means not secured to the body and spaced apart from each other;

removing signals associated with the movements of the body from the obtained signals;

separating signals possibly associated with cardiac and/or respiratory activity from the obtained signals;

determining propagation rates of the pulse waves of cardiac and respiration activities by determining the shift of the obtained cardiac and respiration signals;

comparing the signals representing propagation rates with propagation rate signals obtained from an earlier measurement of the same body;

removing those signals which are not characteristic of the wave propagation rates of said body;

determining the cardiac and respiratory rhythm parameters from the remaining signals;

comparing said parameters with parameters obtained from an earlier measurement of the same body, as well as with predetermined parameters;

separating and removing parameters which differ from said predetermined parameters;

storing, displaying and comparing the separated parameters with parameters obtained from said earlier measurements, and

generating an alarm when one of the parameters exceeds a preset range.