Modular CPR assist device

• US 20020156401A1
• Filed: 06/03/2002
• Published: 10/24/2002
• Est. Priority Date: 05/29/1998
• Status: Active Grant

• Current Assignee: Zoll Circulation Incorporated (Asahi Kasei Corporation)
• Original Assignee: Revivant Corporation (Asahi Kasei Corporation)
• Inventors: Mollenauer, Kenneth H., Sherman, Darren R.
• Granted Patent: US 6,709,410 B2
• Time in Patent Office: Days
• US Class Current: 601/41
• CPC Class Codes: A61H 2011/005 with belt or strap expanding and contracting around an encircled body part
• CPC Class Codes: A61H 2031/003 with alternated thorax decompression due to lateral compression
• CPC Class Codes: A61H 2201/5007 computer controlled
• CPC Class Codes: A61H 2201/5058 Sensors or detectors
• CPC Class Codes: A61H 2201/5069 Angle sensors
• CPC Class Codes: A61H 2230/205 partial CO2-value
• CPC Class Codes: A61H 2230/207 partial O2-value
• CPC Class Codes: A61H 2230/30 Blood pressure A61H2230/04 takes precedence
• CPC Class Codes: A61H 2230/80 Weight
• CPC Class Codes: A61H 2230/85 Contour of the body
• CPC Class Codes: A61H 31/00 Artificial respiration or heart stimulation, e.g. heart massage artificial respiration by treatment with gas or air, e.g. mouth-to-mouth respiration A61M16/00; applying electric currents by contact electrodes for stimulation, e.g. heart pace-makers A61N1/36 ; teaching or training models, demonstration models for medical purposes G09B23/288
• CPC Class Codes: A61H 31/006 Power driven
• CPC Class Codes: A61H 31/008 Supine patient supports or bases, e.g. improving air-way access to the lungs
• CPC Class Codes: Y10S 601/06 Artificial respiration conforming to shape of torso
• CPC Class Codes: Y10S 601/12 Vibrator with computer control

Abstract

A system for performing chest compression for Cardiopulmonary Resuscitation. The system includes a motor, drive spool and associated couplings which allow for controlling and limiting the movement of the compressing mechanism and includes a control system for controlling the operation and interaction of the various components to provide for optimal automatic operation of the system.

Claims

1. A device for compressing a chest of a patient comprising:

a belt adapted to extend around the chest of the patient and fastened on the patient;

a belt take-up means adapted to take up the belt upon rotation of the belt take up means, said belt take-up means operably connected to the belt;

a means for sensing slack take-up, said means for sensing slack take-up being capable of indicating when the belt has fit snugly about the chest of the patient;

a motor operably connected to the belt take up means through a coupling means, said motor capable of operating the belt take up means repeatedly to cause the belt to tighten about the chest of the patient and loosen about the chest of the patient;

a controller for controlling operation of the motor;

wherein said controller is programmed to operate the motor and belt take-up means to take up slack in the belt after initial placement of the belt on the chest of the patient by rotating the motor in a tightening rotation until the means for sensing slack take-up indicates that the belt has fit snugly around the chest of the patient; and

wherein said controller is further programmed to operate the motor, the coupling means, and the belt take up means to cause repeated cycles of tightening of the belt about the chest of the patient and loosening of the belt about the chest of the patient.

2. The chest compression device of claim 1 further comprising:

an encoder operably connected to one of the belt or belt take-up means, so that the encoder is capable of measuring the position of the belt, said encoder being capable of transmitting a belt position signal indicative of the position of the belt to the controller.

3. The chest compression device of claim 2 wherein:

the controller is further programmed, based on the belt position signal, to set a slack-limit position of the belt at the point when the means for sensing slack take-up indicates that the belt has fit snugly about the chest of the patient; and

the controller is further programmed, based on the belt position signal, to operate the motor to limit loosening of the belt to the slack-limit position during operating cycles of the chest compression device.

4. The chest compression device of claim 2 wherein:

the controller is further programmed, based on the belt position signal, to set a slack-limit position of the belt at the point when the means for sensing slack take-up indicates that the belt has fit snugly about the chest of the patient;

the controller is further programmed, based on the slack-limit position, to define a set amount of belt displacement to be used during compressions; and

the controller is further programmed, based on the belt position signal, to operate the motor to limit the take-up of the belt to the set amount of belt displacement.

5. The chest compression device of claim 2 wherein:

the controller is further programmed, based on the belt position signal, to set a slack-limit position of the belt at the point when the means for sensing slack take-up indicates that the belt has fit snugly about the chest of the patient; and

the controller is further programmed, based on the belt position signal, to operate the motor to limit the release of the belt so that the belt does not fully return to the slack limit position.

6. The chest compression device of claim 2 wherein:

the controller is further programmed, based on the belt position signal, to set a slack-limit position of the belt at the point when the means for sensing slack take-up indicates that the belt has fit snugly about the chest of the patient;

the controller is further programmed, based on the belt position signal, to operate the motor to limit loosening of the belt to the slack-limit position during operating cycles of the chest compression device;

the controller is further programmed, based on the slack-limit position, to define a set amount of belt displacement to be used during compressions;

the controller is further programmed, based on the belt position signal, to operate the motor to limit the take-up of the belt to the set amount of belt displacement;

the controller is further programmed to operate the motor to momentarily hold the belt at the set amount of belt displacement and then release the belt; and

the controller is further programmed, based on the belt position signal, to operate the motor to limit the release of the belt so that the belt does not fully return to the slack limit position.

7. The chest compression device of claim 1 wherein the means for sensing slack take-up comprises a means for sensing the torque on the motor.

8. The chest compression device of claim 1 wherein the means for sensing slack take-up comprises a means for sensing the amount of force applied to the belt.

9. The chest compression device of claim 2 wherein the means for sensing slack take-up comprises a means for sensing the torque on the motor.

10. The chest compression device of claim 2 wherein the means for sensing slack take-up comprises a means for sensing the amount of force applied to the belt.

11. The chest compression device of claim 3 wherein the means for sensing slack take-up comprises a means for sensing the torque on the motor.

12. The chest compression device of claim 3 wherein the means for sensing slack take-up comprises a means for sensing the amount of force applied to the belt.

13. The chest compression device of claim 4 wherein the means for sensing slack take-up comprises a means for sensing the torque on the motor.

14. The chest compression device of claim 4 wherein the means for sensing slack take-up comprises a means for sensing the amount of force applied to the belt.

15. The chest compression device of claim 5 wherein the means for sensing slack take-up comprises a means for sensing the torque on the motor.

16. The chest compression device of claim 5 wherein the means for sensing slack take-up comprises a means for sensing the amount of force applied to the belt.

17. The chest compression device of claim 6 wherein the means for sensing slack take-up comprises a means for sensing the torque on the motor.

18. The chest compression device of claim 6 wherein the means for sensing slack take-up comprises a means for sensing the amount of force applied to the belt.

20. The chest compression device of claim 19 further comprising:

an encoder operably connected to one of the belt or belt take-up means, so that the encoder is capable of measuring the position of the belt, said encoder being capable of transmitting a belt position signal indicative of the position of the belt to the controller.

21. The chest compression device of claim 20 wherein:

the controller is further programmed, based on the belt position signal, to set a slack-limit position of the belt at the point when the means for sensing slack take-up indicates that the belt has fit snugly about the chest of the patient; and

the controller is further programmed, based on the belt position signal, to operate the motor to limit loosening of the belt to the slack-limit position during operating cycles of the chest compression device.

22. The chest compression device of claim 20 wherein:

the controller is further programmed, based on the belt position signal, to set a slack-limit position of the belt at the point when the means for sensing slack take-up indicates that the belt has fit snugly about the chest of the patient;

the controller is further programmed, based on the slack-limit position, to define a set amount of belt displacement to be used during compressions; and

the controller is further programmed, based on the belt position signal, to operate the motor to limit the take-up of the belt to the set amount of belt displacement.

23. The chest compression device of claim 20 wherein:

the controller is further programmed, based on the belt position signal, to set a slack-limit position of the belt at the point when the means for sensing slack take-up indicates that the belt has fit snugly about the chest of the patient; and

the controller is further programmed, based on the belt position signal, to operate the motor to limit the release of the belt so that the belt does not fully return to the slack limit position.

24. The chest compression device of claim 20 wherein:

the controller is further programmed, based on the belt position signal, to set a slack-limit position of the belt at the point when the means for sensing slack take-up indicates that the belt has fit snugly about the chest of the patient;

the controller is further programmed, based on the belt position signal, to operate the motor to limit loosening of the belt to the slack-limit position during operating cycles of the chest compression device;

the controller is further programmed, based on the slack-limit position, to define a set amount of belt displacement to be used during compressions;

the controller is further programmed, based on the belt position signal, to operate the motor to limit the take-up of the belt to the set amount of belt displacement;

the controller is further programmed to operate the motor to momentarily hold the belt at the set amount of belt displacement and then release the belt; and

the controller is further programmed, based on the belt position signal, to operate the motor to limit the release of the belt so that the belt does not fully return to the slack limit position.

25. The chest compression device of claim 19 wherein the means for sensing slack take-up comprises a means for sensing the torque on the motor.

26. The chest compression device of claim 19 wherein the means for sensing slack take-up comprises a means for sensing the amount of force applied to the belt.

27. The chest compression device of claim 20 wherein the means for sensing slack take-up comprises a means for sensing the torque on the motor.

28. The chest compression device of claim 20 wherein the means for sensing slack take-up comprises a means for sensing the amount of force applied to the belt.

29. The chest compression device of claim 21 wherein the means for sensing slack take-up comprises a means for sensing the torque on the motor.

30. The chest compression device of claim 21 wherein the means for sensing slack take-up comprises a means for sensing the amount of force applied to the belt.

31. The chest compression device of claim 22 wherein the means for sensing slack take-up comprises a means for sensing the torque on the motor.

32. The chest compression device of claim 22 wherein the means for sensing slack take-up comprises a means for sensing the amount of force applied to the belt.

33. The chest compression device of claim 23 wherein the means for sensing slack take-up comprises a means for sensing the torque on the motor.

34. The chest compression device of claim 23 wherein the means for sensing slack take-up comprises a means for sensing the amount of force applied to the belt.

35. The chest compression device of claim 24 wherein the means for sensing slack take-up comprises a means for sensing the torque on the motor.

36. The chest compression device of claim 24 wherein the means for sensing slack take-up comprises a means for sensing the amount of force applied to the belt.

38. The chest compression device of claim 37 further comprising:

a linear encoder scale on the belt and an encoder scanner located in apposition to the scale, said encoder transmitting an encoder position to the controller;

said controller further programmed to associate the encoder position to the point of rapid increase in the current signal during initial placement thereby defining a slack-limit position of the belt, and to operate the motor to limit loosening of the belt during cycles to the slack-limit position.

40. The chest compression device of claim 39 further comprising:

an encoder means for reading and transmitting a corresponding encoder position to the controller;

wherein said controller is further programmed to associate the encoder means position to the point of rapid increase in the current signal during initial placement thereby defining a slack-limit position of the belt, and to operate the motor to limit loosening of the belt during cycles to the slack-limit position.

19. A device for compressing a chest of a patient comprising:

a belt adapted to extend around the chest of the patient and fastened on the patient;

a belt take-up means adapted to take up the belt upon rotation of the belt take up means, said belt take-up means operably connected to the belt;

a means for sensing slack take-up, said means for sensing slack take-up being capable of indicating when the belt has fit snugly about the chest of the patient;

a motor operably connected to the belt take up means through a coupling means, said motor capable of operating the belt take up means repeatedly to cause the belt to tighten about the chest of the patient and loosen about the chest of the patient;

a means for braking the motor;

a controller for controlling operation of the motor and the brake;

wherein said controller is programmed to operate the motor and belt take-up means to take up slack in the belt after initial placement of the belt on the chest of the patient by rotating the motor in a tightening rotation until the means for sensing slack take-up indicates that the belt has fit snugly around the chest of the patient;

wherein the controller is further programmed to operate the motor, the coupling means, and the belt take up means to cause repeated cycles of tightening of the belt about the chest of the patient and loosening of the belt about the chest of the patient; and

wherein the controller is further programmed to set a threshold of belt tightness and control the brake to momentarily hold the belt at the threshold of belt tightness, and then to release the belt.

37. A device for compressing the chest of a patient comprising:

a belt adapted to extend around the chest of the patient and fastened on the patient;

a drive spool operably connected to the belt and adapted to take up the belt upon rotation of the drive spool;

a motor operably connected to the drive spool through a coupling, said motor capable of operating the drive spool repeatedly to cause the belt to tighten about the chest of the patient and loosen about the chest of the patient;

a controller for controlling operation of the motor;

a current sensor operably connected to the motor, said current sensor adapted to sense current drawn by the motor and transmit a corresponding current signal to the controller;

said controller programmed to operate the motor and drive spool to take up slack in the belt after initial placement of the belt on the patient'"'"'s chest by rotating the motor in a tightening rotation until the current signal provided by the current sensor rapidly increases;

said controller further programmed to operate the motor and coupling and drive spool to cause repeated cycles of tightening of the belt about the chest of the patient and loosening of the belt about the chest of the patient.

39. A device for compressing a chest of a patient comprising:

a belt adapted to extend around the chest of the patient and fastened on the patient;

a belt take up means adapted to take up the belt upon rotation of the belt take up means, said belt take up means operably connected to the belt;

a motor operably connected to the belt take up means through a coupling means, said motor capable of operating the belt take up means repeatedly to cause the belt to tighten about the chest of the patient and loosen about the chest of the patient;

a controller for controlling operation of the motor;

a means for sensing the current drawn by the motor and transmitting a corresponding current signal to the controller;

wherein said controller is programmed to operate the motor and belt take up means to take up slack in the belt after initial placement of the belt on the chest of the patient by rotating the motor in a tightening rotation until the current signal provided by the current sensor rapidly increases;

wherein said controller is further programmed to operate the motor and the coupling means and the belt take up means to cause repeated cycles of tightening of the belt about the chest of the patient and loosening of the belt about the chest of the patient.

41. A device for compressing the chest of a patient comprising:

a belt adapted to extend around the chest of the patient and fastened on the patient;

a drive spool operably connected to the belt and adapted to take up the belt upon rotation of the drive spool;

a motor operably connected to the drive spool through a coupling, said motor capable of operating the drive spool repeatedly to cause the belt to tighten about the chest of the patient and loosen about the chest of the patient;

a controller for controlling operation of the motor;

said controller programmed to operate the motor and drive spool to take up slack in the belt after initial placement of the belt on the patient'"'"'s chest by rotating the motor in a tightening rotation until the belt is snug about the patient'"'"'s chest, thereby defining a slack take up position of the belt;

said controller further programmed to operate the motor and coupling and drive spool to cause repeated cycles of tightening of the belt about the chest of the patient, tighter than the slack take up position, and loosening of the belt about the chest of the patient to the slack take up position.

42. The chest compression device of claim 41 further comprising:

a linear encoder scale on the belt and an encoder scanner located in apposition to the scale, said encoder transmitting an encoder position signal to the controller;

said controller further programmed to associate an encoder position to the slack take up position, and to operate the motor to limit loosening of the belt during cycles to the slack-limit position.

43. The chest compression device of claim 41 further comprising:

an encoder scale and an encoder scanner located in apposition to the scale, said encoder and encoder scale operably connected to a component of the chest compression device, said encoder transmitting an encoder position to the controller;

said controller further programmed to associate an encoder position to the slack take up position, and to operate the motor to limit loosening of the belt during cycles to the slack-limit position.

44. A device for compressing a chest of a patient comprising:

a belt adapted to extend around the chest of the patient and fastened on the patient;

a belt take up means adapted to take up the belt upon rotation of the belt take up means, said belt take up means operably connected to the belt;

a motor operably connected to the belt take up means through a coupling means, said motor capable of operating the belt take up means repeatedly to cause the belt to tighten about the chest of the patient and loosen about the chest of the patient;

a controller for controlling operation of the motor;

a means for sensing the current drawn by the motor and transmitting a corresponding current signal to the controller;

wherein said controller programmed to operate the motor and drive spool to take up slack in the belt after initial placement of the belt on the patient'"'"'s chest by rotating the motor in a tightening rotation until the belt is snug about the patient'"'"'s chest, thereby defining a slack take up position of the belt

wherein said controller is further programmed to operate the motor and the coupling means and the belt take up means to cause repeated cycles of tightening of the belt about the chest of the patient and loosening of the belt about the chest of the patient.

45. The chest compression device of claim 44 further comprising:

an encoder means for reading and transmitting a corresponding encoder position signal, indicative of the position of the belt, to the controller;

said controller further programmed to associate an encoder position to the slack take up position, and to operate the motor to limit loosening of the belt during cycles to the slack-limit position.

48. The method of claim 47 wherein the chest compression device further comprises:

an encoder operably connected to one of the belt or belt take-up means, so that the encoder is capable of measuring the position of the belt, said encoder being capable of transmitting a belt position signal indicative of the position of the belt to the controller;

wherein the controller is further programmed, based on the belt position signal, to set a slack-limit position of the belt at the point when the means for sensing slack take-up indicates that the belt has fit snugly about the chest of the patient; and

wherein the controller is further programmed, based on the belt position signal, to operate the motor to limit loosening of the belt to the slack-limit position during operating cycles of the chest compression device.

49. The method of claim 48 comprising the further step of limiting the loosening of the belt to the slack-limit position during operating cycles of the chest compression device.

50. The method of claim 47 wherein the controller of the chest compression device is further programmed to operate the motor to momentarily hold the belt at the set amount of belt displacement and then release the belt.

51. The method of claim 50 comprising the further step of momentarily holding the belt at the set amount of belt displacement and then releasing the belt.

52. The method of claim 48 wherein the controller of the chest compression device is further programmed to operate the motor to momentarily hold the belt at the set amount of belt displacement and then release the belt.

53. The method of claim 52 comprising the further steps of:

limiting the loosening of the belt to the slack-limit position during operating cycles of the chest compression device; and

momentarily holding the belt at the set amount of belt displacement and then releasing the belt.

46. A method of using a chest compression device to determine a slack-limit position of a belt of the chest compression device, said slack-limit position being set to the size of a particular patient, said method comprising the steps of:

providing the chest compression device, said chest compression device comprising;

a belt adapted to extend around the chest of the patient and fastened on the patient;

a belt take-up means adapted to take up the belt upon rotation of the belt take up means, said belt take-up means operably connected to the belt;

a means for sensing slack take-up, said means for sensing slack take-up being capable of indicating when the belt has fit snugly about the chest of the patient;

a motor operably connected to the belt take up means through a coupling means, said motor capable of operating the belt take up means repeatedly to cause the belt to tighten about the chest of the patient and loosen about the chest of the patient;

a controller for controlling operation of the motor;

wherein said controller is programmed to operate the motor and belt take-up means to take up slack in the belt after initial placement of the belt on the chest of the patient by rotating the motor in a tightening rotation until the means for sensing slack take-up indicates that the belt has fit snugly around the chest of the patient;

wherein said controller is further programmed to operate the motor, the coupling means, and the belt take up means to cause repeated cycles of tightening of the belt about the chest of the patient and loosening of the belt about the chest of the patient;

an encoder operably connected to one of the belt or belt take-up means, so that the encoder is capable of measuring the position of the belt, said encoder being capable of transmitting a belt position signal indicative of the position of the belt to the controller; and

wherein the controller is further programmed, based on the belt position signal, to set a slack-limit position of the belt at the point when the means for sensing slack take-up indicates that the belt has fit snugly about the chest of the patient;

placing the belt around the chest of the patient;

taking up the slack of the belt with the means for taking up slack until the means for sensing slack take up indicates that the belt has fit snugly on the chest of the patient, whereby the slack limit position of the belt is defined to be the position of the belt when the belt fits snugly on the chest of the patient.

47. A method of performing chest compressions, said method comprising the steps of:

providing the chest compression device, said chest compression device comprising;

a belt adapted to extend around the chest of the patient and fastened on the patient;

a belt take-up means adapted to take up the belt upon rotation of the belt take up means, said belt take-up means operably connected to the belt;

a means for sensing slack take-up, said means for sensing slack take-up being capable of indicating when the belt has fit snugly about the chest of the patient;

a motor operably connected to the belt take up means through a coupling means, said motor capable of operating the belt take up means repeatedly to cause the belt to tighten about the chest of the patient and loosen about the chest of the patient;

a controller for controlling operation of the motor;

wherein said controller is programmed to operate the motor and belt take-up means to take up slack in the belt after initial placement of the belt on the chest of the patient by rotating the motor in a tightening rotation until the means for sensing slack take-up indicates that the belt has fit snugly around the chest of the patient; and

wherein said controller is further programmed to operate the motor, the coupling means, and the belt take up means to cause repeated cycles of tightening of the belt about the chest of the patient and loosening of the belt about the chest of the patient.

placing the belt around the chest of the patient;

taking up the slack of the belt with the means for belt take-up until the means for sensing slack take up indicates that the belt has fit snugly on the chest of the patient; and

repeatedly tightening and loosening the belt with belt take-up means.