Blood pressure cuff

• US 9,445,728 B2
• Filed: 02/06/2013
• Issued: 09/20/2016
• Est. Priority Date: 11/08/2011
• Status: Expired due to Fees

• Current Assignee: Elwha LLC (Intellectual Ventures LLC)
• Original Assignee: Elwha LLC (Intellectual Ventures LLC)
• Inventors: Hyde, Roderick A., Kare, Jordin T., McKnight, Gary L., Wood, Lowell L. Jr.
• Primary Examiner(s): Bosworth, Kami A
• Application Number:
  US13/760,932
• Publication Number:
  US 20130245390A1
• Time in Patent Office: 1,322 Days
• Field of Search: 600/301, 600/485, 600490-499, 606/202
• US Class Current: 1/1
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/02208 using the Korotkoff method
• CPC Class Codes: A61B 5/026 Measuring blood flow A61B3/1233, A61B3/1241 take precedence
• CPC Class Codes: A61B 5/1118 Determining activity level
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• CPC Class Codes: A61B 5/6824 Arm or wrist
• CPC Class Codes: A61B 5/6826 Finger
• CPC Class Codes: A61B 5/6828 Leg
• CPC Class Codes: A61B 5/6829 Foot or ankle
• CPC Class Codes: A61B 5/6885 Monitoring or controlling sensor contact pressure
• CPC Class Codes: A61B 5/7475 User input or interface means, e.g. keyboard, pointing device, joystick

Abstract

A device can include a vibration sensor configured to sense blood flow in a lumen of a person; a cuff coupled to the vibration sensor and configured to contact a limb of the person; a mechanical cuff tensioner coupled to the cuff, the mechanical cuff tensioner configured to adjust a compressive force of the cuff on the lumen; a tension sensor operably coupled to the mechanical cuff tensioner, the tension sensor configured to measure a first tension value of the cuff during a first sense by the vibration sensor and to measure a second tension value of the cuff during a second sense by the vibration sensor; and a recorder mechanism configured to record the first tension value, the first measurement by the vibration sensor, the second tension value, and the second measurement by the vibration sensor.

Claims

1. A device, comprising:

a vibration sensor configured to sense blood flow in a lumen of a person;

a cuff coupled to the vibration sensor and configured to contact a limb of the person;

a mechanical cuff tensioner coupled to the cuff, the mechanical cuff tensioner configured to adjust a compressive force of the cuff on the lumen;

a tension sensor operably coupled to the mechanical cuff tensioner, the tension sensor configured to measure a first tension value of the cuff during a first sense by the vibration sensor and to measure a second tension value of the cuff during a second sense by the vibration sensor;

a recorder mechanism configured to record the first tension value, a first measurement by the vibration sensor, the second tension value, and a second measurement by the vibration sensor; and

an energy-recovery mechanism configured to recover energy from activation of the mechanical cuff tensioner to reduce the compressive force of the cuff on the lumen.

2. The device of claim 1, wherein the vibration sensor includes an acoustic sensor.

3. The device of claim 2, further comprising:

a controller operably coupled to the acoustic sensor, the controller including circuitry to determine a Korotkoff sound indicative of at least one systole and diastole based on at least one of the first measurement or the second measurement.

4. The device of claim 1, wherein the vibration sensor includes a piezoelectric sensor.

5. The device of claim 4, further comprising:

a controller operably coupled to the piezoelectric sensor, the controller including circuitry to determine at least one vibration pattern indicative of systole and diastole based on at least one of the first measurement or the second measurement.

6. The device of claim 1, wherein the first measurement by the vibration sensor is at a systolic phase of the blood flow, and wherein the second measurement by the vibration sensor is at a diastolic phase of the blood flow.

7. The device of claim 1, wherein the tension sensor is configured to halt adjustment of the compressive force of the cuff on the lumen by the mechanical cuff tensioner at a designated pressure.

8. The device of claim 7, wherein the designated pressure is a pressure suitable for the vibration sensor to sense blood flow in the lumen.

9. The device of claim 1, further comprising:

a contact sensor operably coupled to the cuff, the contact sensor configured to determine contact between the limb and a torso of the person.

10. The device of claim 1, further comprising:

a controller operably coupled to the recorder mechanism, the controller configured to determine a blood pressure value based on the first tension value, the second tension value, the first measurement by the vibration sensor, and the second measurement by the vibration sensor.

11. The device of claim 10, wherein the recorder mechanism is configured to record the determined blood pressure value.

12. The device of claim 11, further comprising:

a relay mechanism operably coupled to the recorder mechanism, the relay mechanism configured to relay the determined blood pressure value to a healthcare provider.

13. The device of claim 12, wherein the relay mechanism is at least one of (i) configured to immediately relay the determined blood pressure value when the determined blood pressure value is at least one of above a threshold value, below the threshold value, or irregular or (ii) configured to relay, according to a schedule, the determined blood pressure value when the determined blood pressure value is within a normal range.

14. The device of claim 10, wherein the controller is at least one of (i) configured to identify the determined blood pressure value as being at least one of above a threshold value, below the threshold value, or at the threshold value or (ii) configured to generate an alert based upon the determined blood pressure value.

15. The device of claim 11, wherein the vibration sensor is configured to measure a pulse rate.

16. The device of claim 15, wherein the recorder mechanism is configured to record the measured pulse rate.

17. The device of claim 16, further comprising:

a relay mechanism operably coupled to the recorder mechanism, the relay mechanism configured to relay the measured pulse rate to a healthcare provider.

18. The device of claim 17, wherein the relay mechanism is at least one of (i) configured to immediately relay the measured pulse rate when the measured pulse rate is at least one of above a threshold value, below the threshold value, or irregular or (ii) configured to relay, according to a schedule, the measured pulse rate when the measured pulse rate is within a normal range.

19. The device of claim 15, further comprising:

a controller operably coupled to the recorder mechanism, the controller configured to identify the measured pulse rate as being at least one of above a threshold value, below the threshold value, or at the threshold value, wherein the controller is configured to generate an alert based upon the measured pulse rate.

20. The device of claim 1, wherein the vibration sensor is configured to measure a pulse structure.

21. The device of claim 20, wherein the recorder mechanism is configured to record the measured pulse structure.

22. The device of claim 21, further comprising:

a relay mechanism operably coupled to the recorder mechanism, the relay mechanism configured to relay the measured pulse structure to a healthcare provider.

23. The device of claim 22, wherein the relay mechanism is at least one of (i) configured to immediately relay the measured pulse structure when the measured pulse structure is at least one of above a threshold value, below the threshold value, or irregular or (ii) configured to relay, according to a schedule, the measured pulse structure when the measured pulse structure is within a normal range.

24. The device of claim 20, further comprising:

a controller operably coupled to the recorder mechanism, the controller configured to identify the measured pulse structure as being at least one of above a threshold value, below the threshold value, or at the threshold value, wherein the controller is configured to generate an alert based upon the measured pulse structure.

25. The device of claim 1, wherein the mechanical cuff tensioner is configured to adjust the compressive force of the cuff on the lumen according to a scheduled activation.

26. The device of claim 1, further comprising:

a user input device, wherein the mechanical cuff tensioner is configured to adjust the compressive force of the cuff on the lumen upon a user-given command via the user input device.

27. The device of claim 1, further comprising:

a sensor configured to sense a physiological condition of the person, wherein the mechanical cuff tensioner is configured to adjust the compressive force of the cuff on the lumen upon the sensed physiological condition.

28. The device of claim 27, wherein the sensed physiological condition includes at least one of a blood oxygenation level or a pulse rate.

29. The device of claim 1, further comprising:

a sensor configured to sense a user activity level, wherein the mechanical cuff tensioner is configured to adjust the compressive force of the cuff on the lumen upon the user activity level.

30. The device of claim 29, wherein the user activity level includes at least one of a systemic activity level or a local activity level.

31. The device of claim 29, wherein the sensor includes an accelerometer configured to measure a motion of the limb, and wherein the user activity level includes the motion of the limb.

32. The device of claim 1, wherein the mechanical cuff tensioner is configured to automatically reduce compressive force applied to the lumen upon occurrence of an event.

33. The device of claim 32, wherein the event is a tension value measured by the tension sensor reaching a maximum tension limit.

34. The device of claim 33, wherein the maximum tension limit is at least one of a preset limit or a user-specified limit.

35. The device of claim 32, further comprising:

at least one of (i) a user input device, wherein the event is a user-given command via the user input device or (ii) a timer device operably coupled to the mechanical cuff tensioner, the timer device configured to measure a time-at-tension value of the mechanical cuff tensioner, wherein the event is exceeding a specified time-at-tension value.

36. The device of claim 1, wherein the limb includes at least one of an arm, a finger, a leg, or a toe.

37. The device of claim 1, wherein a length of the cuff is configured to extend partially around the limb, and wherein the cuff includes a first end and a second end, the cuff defining a gap between the first end and the second end.

38. The device of claim 1, further comprising:

a controller configured to calculate at least one of a systolic blood pressure or a diastolic blood pressure based on the first tension value, the second tension value, and at least one of a circumference of the cuff, a lateral dimension of the cuff, or an eccentricity factor of the cuff.

39. The device of claim 1, further comprising:

a power source operably coupled to at least one of the vibration sensor, the tension sensor, or the mechanical cuff tensioner.

40. The device of claim 1, wherein the mechanical cuff tensioner includes at least one of (i) an electroactive polymer or (ii) a flexible member attached to a rotatable member.

41. The device of claim 40, wherein the mechanical cuff tensioner includes the flexible member attached to the rotatable member, and wherein the flexible member is configured to wind around the rotatable member to tighten the cuff and to unwind around the rotatable member to loosen the cuff.

42. The device of claim 1, further comprising:

at least one of (i) a battery coupled to the energy-recovery mechanism and configured to store the recovered energy or (ii) a capacitor coupled to the energy-recovery mechanism and configured to buffer the recovered energy.

43. The device of claim 1, wherein the mechanical cuff tensioner is at least one of mechanically powered or battery powered.

44. The device of claim 1, wherein the mechanical cuff tensioner includes a connector mechanism configured to position a first end the cuff in proximity to a second end of the cuff, and wherein the connector mechanism is configured to adjust the compressive force of the cuff on the lumen by adjusting the position of the first end of the cuff relative to the position of the second end of the cuff.

45. The device of claim 44, wherein the connector mechanism includes at least one of a lever or a motor.

46. The device of claim 1, wherein the mechanical cuff tensioner includes a connector mechanism configured to overlap at least a portion of the cuff, and wherein the connector mechanism is configured to adjust the compressive force of the cuff on the lumen by adjusting the overlap.

47. The device of claim 46, wherein the connector mechanism includes at least one of a lever or a motor.

48. The device of claim 1, further comprising:

a motion sensor operably coupled to the recorder mechanism, the motion sensor configured to detect a motion of the cuff, wherein the motion sensor includes circuitry that disables the mechanical cuff tensioner when the motion exceeds a threshold or disables the tension sensor when the motion exceeds a threshold.

49. The device of claim 1, further comprising:

an inclinometer operably coupled to the cuff, the inclinometer configured to detect an orientation of the cuff, wherein the vibration sensor is configured to activate when the orientation is within a specified range.

50. The device of claim 49, further comprising:

a controller configured to determine a correction factor based upon the orientation.