Method and apparatus for performing cardio-pulmonary resuscitation with active reshaping of chest

• US 5,743,864 A
• Filed: 06/29/1995
• Issued: 04/28/1998
• Est. Priority Date: 06/29/1995
• Status: Expired due to Term

• Current Assignee: Michigan Instruments, Inc. (Grand Ridge Holdings LLC)
• Original Assignee: Michigan Instruments, Inc. (Grand Ridge Holdings LLC)
• Inventors: Baldwin, R. Mitchell II
• Primary Examiner(s): CLARK, JEANNE MARIE
• Application Number:
  US08/496,732
• Time in Patent Office: 1,034 Days
• Field of Search: 601/1, 601/41, 601/42, 601/43, 601/44, 601/134, 601/135, 607/108, 607/114, 602/13, 128/DIG. 20
• US Class Current: 601/41
• CPC Class Codes: A61H 2031/003 with alternated thorax decompression due to lateral compression
• CPC Class Codes: A61H 2201/1238 with hydraulic or pneumatic drive
• CPC Class Codes: A61H 2201/5071 Pressure sensors
• 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

Abstract

An apparatus and method for performing cardio-plumonary resuscitation with active reshaping of a patient'"'"'s chest are disclosed. A piston positioned near a patient'"'"'s sternum is intermittently activated to produce cycles of direct compression on the patient'"'"'s heart while an annular collar is simultaneously placed securely around a patient'"'"'s thoracic cavity to limit the circumferential changes in the thoracic cavity. The combination of the annular collar and piston combine to direct blood flow both by direct cardiac compression/decompression and by varying the intrathoracic cavity pressure. The annular collar can be formed by a single non-extensible membrane or by a non-extensible outer membrane and an extensible inner membrane with a bladder therebetween filled with a substantially non-compressible fluid. The collar may be attached to the piston and the piston actively driven away from the patient during decompression resulting in an active reshaping of the chest to lower central venous pressure and thereby induce a rapid return of blood to the thoracic cavity.

Claims

1. A method of performing cardio-pulmonary resuscitation, including:

restraining the circumference of a patient'"'"'s thoracic cavity with a substantially non-extensible annular collar;

intermittently applying a compression force directed inwardly toward the patient from a location outwardly of the collar to the collar while the patient is supported posteriorly, wherein the collar transfers the external compression force through the collar to the patient'"'"'s sternum in order to apply direct cardiac compression and wherein the collar translates the external compression force to a lateral restraint of the patient'"'"'s chest in order to increase the intrathoracic cavity pressure of the patient; and

actively reshaping the patient'"'"'s thoracic cavity after each said applying in order to decrease intrathoracic cavity pressure of the patient, wherein said actively reshaping includes applying a compression force between opposite sides of the patient'"'"'s chest, wherein said applying a compression force between opposite sides of the patient'"'"'s chest includes applying an extension force to said annular collar in a direction anterior the patient'"'"'s sternum.

2. A method of performing cardio-pulmonary resuscitation, including:

restraining the circumference of a patient'"'"'s thoracic cavity with a substantially non-extensible annular collar;

intermittently applying a compression force directed inwardly toward the patient form a location outwardly of the collar to the collar while the patient is supported posteriorly, wherein the collar transfers the external compression force through the collar to the patient'"'"'s sternum in order to apply direct cardiac compression and wherein the collar translates the external compression force to a lateral restraint of the patient'"'"'s chest in order to increase the intrathoracic cavity pressure of the patient; and

wherein said non-extensible collar includes an annular outer substantially non-extensible membrane and an annular interior extensible membrane positioned against the patient'"'"'s chest defining an interior cavity in said collar between said membranes and a non-compressible fluid in said cavity, and wherein said applying a compression force includes compressing said cavity in order to compress the patient'"'"'s thoracic cavity.

3. The method of claim 2 wherein said applying a compression force includes connecting said annular collar with a reciprocating piston that is actively driven in at least a posterior direction.

11. The apparatus in claim 2 wherein said annular collar includes an endless member made from a non-extensible fabric.

4. A method of performing cardio-pulmonary resuscitation, including:

at least partially surrounding the patient'"'"'s thoracic cavity with a strap and connecting said strap to a piston which is reciprocated by an actuating device;

applying a compression force between a patient'"'"'s sternum and spine by intermittently driving said piston with said actuating device toward the patient'"'"'s sternum; and

actively reshaping the patient'"'"'s thoracic cavity after each said applying by actively driving said piston with said actuating device away from the patient'"'"'s sternum in order to pull portions of the strap away from the patient and thereby decrease intrathoracic cavity pressure of the patient by applying a compression force between opposite sides of the patient'"'"'s chest.

5. The method of claim 4 wherein said at least partially surrounding the patient'"'"'s thoracic cavity with a strap includes restraining the circumference of the patient'"'"'s thoracic cavity with a substantially non-extendable annular collar, wherein the collar translates the compression force to a lateral restraint of the patient'"'"'s chest in order to increase the intrathoracic cavity pressure of the patient.

6. The method of claim 5 wherein said annular collar includes an endless member made from a non-extensible fabric.

7. The method in claim 5 wherein said annular collar includes an outer membrane made from a non-extensible fabric and an inner membrane thereby defining a cavity between said inner and outer membranes and further including a non-compressible fluid in said cavity.

8. The method in claim 7 wherein said non-compressible fluid is a hydraulic liquid.

9. A cardio-pulmonary resuscitation apparatus comprising:

a posterior support for a patient;

a reciprocating piston and an actuating device actively driving said piston alternatingly toward and away from said support, said actuating device substantially rigidly interconnected with said support, wherein said piston includes a pad at one end of said piston which alternatingly compresses and releases the sternum of a patient on said support; and

a strap configured to substantially surround a patient'"'"'s chest, said strap substantially rigidly joined directly to said piston pad wherein said pad and the portion of said strap attached to said pad move simultaneously and in unison in order to pull said portion of the strap away from a patient and thereby actively reshape the a patient'"'"'s thoracic cavity when said piston is driven away from the support and thereby decrease intrathoracic cavity pressure of a patient.

10. The cardio-pulmonary resuscitation apparatus in claim 9 wherein said strap is a substantially non-extensible annular collar configured to closely surround a patient'"'"'s chest in order to restrain the circumference of a patient'"'"'s thoracic cavity when said piston is driven toward said support producing a compressive force which the collar transfers to a patient'"'"'s sternum thereby applying direct cardiac compression and which collar translates to a lateral restraint of a patient'"'"'s chest increasing the intrathoracic cavity pressure of a patient.

12. The apparatus in claim 10 wherein said annular collar includes an outer membrane made from a non-extensible fabric and an inner membrane, thereby defining a cavity between said inner and outer membranes, and further including a non-compressible fluid in said cavity.

13. The apparatus in claim 12 wherein said non-compressible fluid is a hydraulic liquid.

14. A method of performing cardio-pulmonary resuscitation, including:

providing a reciprocating piston which is actively driven by an actuating device;

restraining the circumference of a patient'"'"'s thoracic cavity with a substantially non-extensible collar attached to said piston;

applying a concentrated compression force between a patient'"'"'s sternum and spine by intermittently driving said piston toward the patient'"'"'s sternum in order to apply direct cardiac compression, wherein said compression force is translated by said collar to laterally restrain the patient'"'"'s chest in order to increase the patient'"'"'s intrathoracic cavity pressure; and

after said applying, actively reshaping the patient'"'"'s thoracic cavity by imermittently driving said piston away from the patient'"'"'s sternum and thereby decreasing intrathoracic cavity pressure of the patient;

wherein said non-extensible collar includes an annular outer substantially non-extensible membrane and an annular interior extensible membrane positioned against the patient'"'"'s chest defining an interior cavity in said collar between said membranes and a non-compressible fluid in said cavity, and wherein said applying a concentrated compression force includes compressing said cavity in order to compress the patient'"'"'s thoracic cavity.