CPR APPARATUS AND METHOD

• US 20100185127A1
• Filed: 01/14/2009
• Published: 07/22/2010
• Est. Priority Date: 05/07/2008
• Status: Active Grant

• Current Assignee: Physio-Control Incorporated (Stryker Corporation)
• Original Assignee: Physio-Control Incorporated (Stryker Corporation)
• Inventors: Nilsson, Anders, Jeppson, Anders
• Granted Patent: US 8,690,804 B2
• Time in Patent Office: Days
• US Class Current: 601/41
• CPC Class Codes: A61H 2201/0173 Means for preventing injuries
• CPC Class Codes: A61H 2201/018 By limiting the applied torque or force
• CPC Class Codes: A61H 2201/50 Control means thereof
• CPC Class Codes: A61H 2201/5007 computer controlled
• CPC Class Codes: A61H 2201/5023 Interfaces to the user
• CPC Class Codes: A61H 2201/5061 Force sensors
• CPC Class Codes: A61H 2201/5064 Position sensors
• CPC Class Codes: A61H 2230/04 Heartbeat characteristics, e.g. E.G.C., blood pressure modulation
• CPC Class Codes: A61H 2230/10 Electroencephalographic signals
• 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 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 31/004 Heart stimulation
• CPC Class Codes: A61H 31/005 with feedback for the user
• CPC Class Codes: A61H 31/006 Power driven

Abstract

A CPR apparatus includes a chest compression unit and a means for mounting the chest compression unit on a patient. The chest compression unit includes a plunger disposed in a housing. At its one end extending from the housing, the plunger has a compression member. The plunger is driven in a reciprocating manner by a reversible electromotor via a mechanical device for translating rotational motion of the motor to linear motion of the plunger or the plunger is driven by a linear induction electromotor. An electromotor control unit including a microprocessor, a first monitor for monitoring the position of the plunger in respect of the housing and a second monitor for monitoring the position of the plunger in respect of the mechanical device for translating rotational motion to linear motion or the rotor of the linear induction electromotor. The monitored positions are communicated to the electromotor control unit. Also disclosed is a corresponding CPR method.

Claims

1. A CPR apparatus comprising

a chest compression unit, a mounting device for mounting the chest compression unit on a patient, the chest compression unit comprising a housing, a plunger disposed in the housing, a compression member at one end of the plunger and extending from the housing,

a reversible electromotor, a mechanical device connected from the motor to the plunger for driving the plunger in a reciprocating manner with respect to the housing and for translating rotational motion of the motor to linear motion of the plunger,

an electromotor control unit connected to the motor and including a microprocessor, a first monitor operable for monitoring the position of the plunger in respect of the housing, a second monitor operable for monitoring the position of the plunger in respect of the mechanical device for translating rotational motion to linear motion or the rotor, the positions monitored by the first and second monitors being communicated to the electromotor control unit.

2. The CPR apparatus of claim 1, further comprising a first compression spring coil which is operable by the mechanical device for translating rotational motion to linear motion and is disposed between the and the plunger.

3. The CPR apparatus of claim 1, wherein the device for translating rotational motion to linear motion comprises a ball screw nut mounted on a ball screw shaft driven by the electromotor.

4. The CPR apparatus of claim 1, wherein the mounting device comprises a frame or scaffold comprising a base and the housing is arranged on the base displaceably along an axis of translational movement of the plunger in a releaseably securable manner.

5. The CPR apparatus of claim 1, wherein the electromotor further comprises an exchangeable battery of high energy density.

6. The CPR apparatus of claim 3, wherein the ball screw nut is disposed in the housing.

7. The CPR apparatus of claim 6, wherein the ball screw nut further comprises a nut holder operable for holding the ball screw nut, the nut holder having a proximal portion that extends into the plunger through a distal opening of the plunger.

8. The CPR apparatus of claim 1, wherein the first monitor includes a linear potentiometer.

9. The CPR apparatus of claim 1, wherein the second monitor includes a Hall effect monitor or a motor shaft rotation monitor.

10. The CPR apparatus of claim 1, wherein at least a portion of the housing extends from the proximal end thereof and is substantially cylindrical.

11. The CPR apparatus of claim 1, further comprising a centering device for centering the plunger in the housing.

12. The CPR apparatus of claim 3, wherein the housing comprises a distal end wall through which the ball screw shaft extends.

13. The CPR apparatus of claim 12, wherein the ball screw shaft portion extending from the housing comprises a pulley.

14. The CPR apparatus of claim 13, wherein the pulley is a toothed belt pulley or a V-belt pulley and the driving shaft of the electromotor comprises a pulley of same kind, such that rotation of the electromotor pulley is transferred to the ball screw shaft pulley by a toothed belt or a V-belt.

15. The CPR apparatus of claim 7, further comprising a first compression spring coil which is operable by the mechanical device for translating rotational motion to linear motion and is disposed between the mechanical device and the plunger;

and

the first compression spring coil is disposed between a proximal face of the ball screw nut holder and a distal face of the compression member.

16. The CPR apparatus of claim 15, further comprising a second compression spring coil operable by the mechanical device for translating rotational motion to linear motion and disposed between a distal face of the ball screw nut holder and a proximal face of a distal radial flange of the plunger.

17. The CPR apparatus of claim 16, wherein the ratio of the spring coil constants of the first and second compression spring coils is from 150:

1 to 1200;

1.

18. The CPR apparatus of claim 4, wherein the scaffold or frame extends from a back plate and is dimensioned for enclosing the chest of an adult person.

19. The CPR apparatus of claim 16, wherein the electromotor control unit includes software operable for calculating the pressure exerted by the plunger on the patient'"'"'s chest from the positions monitored by the first and second position monitors, the first compression spring coil constant and, optionally, the second compression spring coil constant, and for controlling the displacement of the plunger based on the pressure.

20. The CPR apparatus of claim 19, wherein the electromotor control unit includes waveform software for modifying the displacement of the plunger over a compression/decompression cycle.

21. The CPR apparatus of claim 1, wherein the electromotor control unit includes a data storage device comprising a real time clock for storing data processed by the unit and assigning a time to said data, the data storage device being optionally removable and readable in a computer or similar.

22. The CPR apparatus of claim 1, further comprising a safety CPR control unit independent of the electromotor control unit, the safety CPR control unit comprising a microprocessor, a plunger position monitoring probe in electric communication with the microprocessor, a temperature monitoring probe, and optionally an electric audio alarm, the safety CPR control unit being energized by a battery, the safety CPR control unit being operable to reverse the electromotor and to stop the electromotor when a temperature or positional limit stored in the microprocessor is exceeded.

27. The CPR apparatus of claim 16, wherein the ratio of the spring coil constants of the first and second compression spring coils is 350:

1.

28. The CPR apparatus of claim 15, wherein the electromotor control unit includes software operable for calculating the pressure exerted by the plunger on the patient'"'"'s chest from the positions monitored by the first and second position monitors, the first compression spring coil constant and for controlling the displacement of the plunger based on the pressure.

23. A method of cardiopulmonary resuscitation comprising

administering to a sternum region of a patient cyclic compressions and decompressions via a plunger in a CPR apparatus, driving the plunger by a reversible electromotor via a converting device for converting rotational movement of the motor into translational movement of the plunger, and

optionally comprising a compression spring coil operatively disposed between the converting device and the plunger.

24. The method of claim 23, comprising controlling the electromotor by a microprocessor based on plunger position data, converting device position data and compression coil spring constant data.

25. The method of claim 23, wherein the device for converting rotational movement into translational movement comprises a ball screw and wherein the electromotor is controlled by a microprocessor based on plunger position data, ball screw position data and compression spring coil constant data.

26. (canceled)

29. A CPR apparatus comprising

a chest compression unit, a mounting device for mounting the chest compression unit on a patient, the chest compression unit comprising a housing, plunger disposed in the housing, a compression member at one end of the plunger and extending from the housing,

a linear induction motor comprising a stator affixed to the housing and a rotor capable of linear motion and surrounding the stator, a connection from the rotor to the plunger for driving the plunger in a reciprocating manner,

an induction motor control unit including a microprocessor, a monitor operable for monitoring the position of the plunger in respect of the housing, the position monitored by the monitor being communicated to the induction motor control unit.

30. The CPR apparatus of claim 29, wherein a first compression spring coil operable by the rotor is disposed between the rotor and the plunger.

31. A method of cardiopulmonary resuscitation comprising administering to a sternum region of a patient cyclic compressions and decompressions by a plunger in a CPR apparatus, driving the plunger by a linear induction electromotor comprising a stator and a rotor connected with the plunger, and

optionally comprising a compression spring coil means operatively disposed between the rotor and the plunger.

32. The method of claim 31, further comprising controlling the linear induction electromotor by a microprocessor based on plunger position data, rotor position data and compression spring coil constant data.