CPR assist device with pressure bladder feedback

• US 20020177793A1
• Filed: 05/25/2001
• Published: 11/28/2002
• Est. Priority Date: 05/25/2001
• Status: Active Grant

• Current Assignee: Zoll Circulation Incorporated (Asahi Kasei Corporation)
• Original Assignee: Revivant Corporation (Asahi Kasei Corporation)
• Inventors: Miner, Cameron, Mollenauer, Kenneth H., Sherman, Darren R.
• Granted Patent: US 6,616,620 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 2201/0103 inflatable
• CPC Class Codes: A61H 2201/0176 By stopping operation
• CPC Class Codes: A61H 2201/018 By limiting the applied torque or force
• CPC Class Codes: A61H 2201/5007 computer controlled
• CPC Class Codes: A61H 2201/501 connected to external computer devices or networks
• CPC Class Codes: A61H 2201/5012 using the internet
• CPC Class Codes: A61H 2201/5043 Displays
• CPC Class Codes: A61H 2201/5058 Sensors or detectors
• CPC Class Codes: A61H 2201/5061 Force sensors
• CPC Class Codes: A61H 2201/5064 Position sensors
• CPC Class Codes: A61H 2201/5071 Pressure sensors
• CPC Class Codes: A61H 2201/5089 Gas sensors, e.g. for oxygen or CO2
• CPC Class Codes: A61H 2201/5097 wireless
• CPC Class Codes: A61H 2230/04 Heartbeat characteristics, e.g. E.G.C., blood pressure modulation
• 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 31/005 with feedback for the user
• 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: A61M 16/00 : Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes stimulating the respiratory movement by mechanical, pneumatic or electrical means, iron lungs combined with gas breathing means A61H31/00
• CPC Class Codes: A61M 16/10 : Preparation of respiratory gases or vapours
• CPC Class Codes: A61M 2205/3546 : Range
• CPC Class Codes: A61M 2230/432 : partial CO2 pressure (P-CO2)
• CPC Class Codes: A61N 1/046 : Specially adapted for shock therapy, e.g. defibrillation
• CPC Class Codes: A61N 1/0472 : Structure-related aspects
• CPC Class Codes: A61N 1/0492 : Patch electrodes A61N1/0412, A61N1/0428 take precedence
• CPC Class Codes: A61N 1/39044 : in combination with cardiopulmonary resuscitation [CPR] therapy
• CPC Class Codes: A61N 1/3968 : Constructional arrangements, e.g. casings A61N1/375 takes precedence
• CPC Class Codes: Y10S 601/06 : Artificial respiration conforming to shape of torso
• CPC Class Codes: Y10S 601/08 : Artificial respiration with computer control

Abstract

A resuscitation device for automatic compression of a victim'"'"'s chest using a compression belt which exerts force evenly over the entire thoracic cavity. The belt is constricted and relaxed through a motorized spool assembly that repeatedly tightens the belt and relaxes the belt to provide repeated and rapid chest compression.

Claims

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

a belt adapted to extend at least partially around the chest of the patient, said belt characterized by a paid-out portion and a spooled portion;

a spool operably connected to the belt to wind and unwind the belt upon the spool, thereby affecting the lengths of the spooled and paid-out portions of the belt;

a motor operably connected to the spool, and operable to rotate the spool and tighten the belt about the chest of the patient;

a controller for controlling the operation of the motor; and

force sensing means disposed between the belt and the patient when the belt is fastened around the patient, said force sensing means operable to sense force applied by the belt to the chest and transmit a signal corresponding to the force applied by the belt to the controller;

said controller being programmed to control the operation of the motor in response to the signal corresponding to force applied by the belt.

2. The device of claim 1 further comprising:

an encoder which measures the change in the length of the paid-out portion of the belt during a compression and sends a signal corresponding to the change in length of the belt to the controller;

wherein the controller is programmed to control operation of the motor by initiating operation of the motor to tighten the belt about the chest of the patient, and continue tightening operation of the motor until the signal corresponding to the change in the length of the paid-out portion indicates that optimal resuscitative compression of the patient'"'"'s chest has been achieved.

3. The device of claim 1 wherein the controller is programmed to control operation of the motor by initiating operation of the motor to tighten the belt about the chest of the patient, and continue tightening operation of the motor until the signal corresponding to the force applied by the belt reaches a predetermined set-point.

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

a belt adapted to extend at least partially around the chest of the patient;

a bladder adapted to be disposed between the belt and the patient when the belt is fastened around the patient, said bladder being filled with a pressure transmitting medium;

a motor operably connected to the belt, and operable to tighten the belt about the chest of the patient;

a controller for controlling the operation of the motor; and

a pressure sensor operably connected to the bladder, said pressure sensor operable to monitor pressure in the bladder and transmit a signal corresponding to pressure in the bladder to the controller;

said controller being programmed to control the operation of the motor in response to the signal corresponding to the pressure in the bladder transmitted by the pressure sensor.

5. The device of claim 4 wherein the controller is programmed to control operation of the motor by initiating operation of the motor to tighten the belt about the chest of the patient, and continue tightening operation of the motor until the signal corresponding to pressure in the bladder reaches a predetermined set-point.

6. The device of claim 4 further comprising:

an encoder operably connected to the belt which sends a signal corresponding to a change in the paid-out length of the belt to the controller;

wherein the controller is programmed to control operation of the motor by initiating operation of the motor to tighten the belt about the chest of the patient, and continue tightening operation of the motor until the signal corresponding to the change in length of the belt indicates that a desired compression threshold has been achieved.

7. The device of claim 6 wherein:

the controller is programmed to determine when desired compression of the patient'"'"'s chest has been achieved by analyzing the signal corresponding to pressure in the bladder and the signal corresponding to change in length of the belt to determine when the ratio of the change of pressure in the bladder to the change of belt length reaches a predetermined ratio.

8. The device of claim 6 wherein:

the controller is programmed to determine when desired compression of the patient'"'"'s chest has been achieved by analyzing the signal corresponding to pressure in the bladder and signal corresponding to change in length of the belt to determine when the ratio of a first value corresponding to the ratio of the pressure in the bladder to the rate of change of belt length and a second value corresponding to the pressure in the bladder reaches a predetermined ratio.

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

a belt adapted to extend at least partially around the chest of the patient;

a drive spool connected to the belt such that rotation of the drive spool results in take up of the belt about the spool;

a motor for operating the drive spool; and

a non-reversing coupling operably connecting the motor to the drive spool.

10. The device of claim 9 wherein the non-reversing coupling has an input shaft connecting the motor to the non-reversing coupling and an output shaft connecting the non-reversing coupling to the drive spool, and said non-reversing coupling allows the motor to rotate the input shaft and thereby rotate the drive spool in a first direction to tighten the belt about the patient'"'"'s chest and allows the motor to rotate the input shaft in a second direction to loosen the belt about the patient'"'"'s chest, and said non-reversing coupling prevents the output shaft from rotating due to rotational forces exerted on the output shaft by the drive spool.

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

a belt adapted to extend at least partially around the chest of the patient;

a drive spool operably connected to the belt for repeatedly tightening and loosening the belt around the chest of the patient;

a brake having a brake shaft, said brake operably connected to the drive spool and capable of holding the drive spool in a tightened state about the chest of the patient;

a motor operably connected to the drive spool through a drive train, 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;

said drive train comprising a motor shaft, a gearbox with a gearbox output shaft, a first sprocket wheel mounted on the gearbox output shaft and a second sprocket wheel mounted on the gearbox output shaft;

said brake being connected to the first sprocket wheel through a first chain, said first chain connected to a third socket wheel which is connected to the brake shaft;

said drive spool being connected to the second sprocket wheel through a second chain, said second chain connected to a fourth socket wheel which is connected to the drive spool;

a controller for controlling operation of the motor and brake, said controller programmed to operate the motor and brake to cause repeated cycles of tightening and loosening of the belt, and intermittently operating the brake to hold the belt at a threshold of tightness.

12. The device of claim 11 wherein the first sprocket wheel and second sprocket wheel are sized relative to each other to effect a gearing change which increases the speed of the brake shaft relative to the gearbox output shaft.

13. The device of claim 12 where the second sprocket wheel and third sprocket wheel are sized relative to each other to effect a gearing change which decreases the speed of the drive spool relative to the gearbox output shaft.

15. The device of claim 14 wherein the second sprocket wheel and third sprocket wheel are sized relative to each other to effect a gearing change which increases the speed of the brake shaft relative to the drive spool.

17. The device of claim 16, further comprising:

a second platform disposed between the first platform and the patient, said second platform adapted to extend horizontally relative to the patient approximately spanning the spinal gap, and extending vertically under the spine so that it substantially overlies the slot and creates a gap on the left side and the right side of the slot between the second platform and the first platform;

wherein the belt extends upwardly through the slot, a right side portion of the belt extends through the gap on right side of the slot, and a left side portion of the belt extends through the gap on the left side of the slot, and said right and left side portions of the belt are adapted to extend around the patient and be fastened together around the patient'"'"'s torso.

18. The device of claim 16 wherein the drive spool has a diameter of approximately 0.5 cm to 2.5 cm, and is adapted to rotate through more than a single rotation during each compression of the chest.

20. The device of claim 19 wherein the rotating member has a diameter in the range of 0.5 cm to 2.5 cm.

14. 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 for repeatedly tightening and loosening the belt around the chest of the patient;

a motor operably connected to the drive spool through a drive train, 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;

said drive train comprising a motor shaft, a gearbox with a gearbox output shaft, a first sprocket wheel mounted on the gearbox output shaft, said first sprocket wheel being connected to a second sprocket wheel mounted on the drive spool through a first chain;

a brake having a brake shaft, and a third socket wheel mounted therein, said third socket wheel being connected to a fourth sprocket wheel through a second chain; and

a controller for controlling operation of the motor and brake, said controller programmed to operate the motor and brake to cause repeated cycles of tightening and loosening of the belt, and intermittently operating the brake to hold the belt at a threshold of tightness.

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

a first platform adapted to support the patient'"'"'s upper body in relation to a belt;

said first platform sized and dimensioned to span across the back of the patient, spanning approximately across the patient'"'"'s body;

said first platform having a slot extending vertically relative to the patient, and located approximately at the horizontal midpoint of the platform relative to the patient;

said belt adapted to extend upwardly through said slot and adapted to extend around the chest of the patient and be fastened around the torso of the patient;

a drive spool operably connected to the belt for repeatedly tightening and loosening the belt around the chest of the patient, said drive spool located laterally distant from the spine, at the side of the patient.

19. A device for compressing the chest of a patient comprising;

a belt which is adapted to extend at least partially around the chest of the patient;

a rotating member operatively connected to the belt such that rotation of the rotating member spools the belt upon the rotating member to constrict the belt about the chest of the patient;

a motor for rotating the rotating member;

said rotating member being of a diameter chosen so as to require rotation exceeding one full rotation of the drive spool to effect resuscitative compression of the chest.