PULSATILE BY-PASS BLOOD PUMP

• US 3,656,873 A
• Filed: 11/06/1970
• Issued: 04/18/1972
• Est. Priority Date: 11/06/1970
• Status: Expired due to Term

• Current Assignee: IABP Corporation
• Original Assignee: Peter Schiff
• Inventors: Schiff, Peter
• Primary Examiner(s): Croyle, Carlton R.
• Assistant Examiner(s): Gluck, Richard E.
• Application Number:
  US05/087,487
• Time in Patent Office: 529 Days
• Field of Search: 417/474,475,395,540 3/1R 128/1
• US Class Current: 417/395
• CPC Class Codes: A61M 60/113 in other functional devices, e.g. dialysers or heart-lung machines
• CPC Class Codes: A61M 60/38 Blood oxygenation
• CPC Class Codes: A61M 60/43 using vacuum at the blood pump, e.g. to accelerate filling
• CPC Class Codes: A61M 60/851 Valves
• CPC Class Codes: A61M 60/892 Active valves, i.e. actuated by an external force
• CPC Class Codes: A61M 60/894 Passive valves, i.e. valves actuated by the blood
• CPC Class Codes: A61M 60/896 having flexible or resilient parts, e.g. flap valves
• CPC Class Codes: Y10S 128/03 Heart-lung

Abstract

A by-pass pump system especially adapted for use in assisting or temporarily replacing the circulatory function of the heart in which a pair of highly elastic collapsible containers are coupled to one another through a resilient flap valve. Each flexible chamber is positioned within an associated housing whose interior pressure is regulated to control the expansion and contraction of the flexible housings. Blood enters the first of said chambers causing the chamber to fill when the blood pressure is greater than the pressure of the surrounding housing. The one-way valve mechanism enables the blood filling the first flexible chamber to enter the second flexible chamber when the interior pressure of the second flexible chamber is lower than that of the first chamber. Conversely, if the pressure within the interior of the second resilient chamber is greater than that within the first flexible container, the one-way valve structure prevents reverse flow. Pneumatic means is coupled to the housing surrounding the second flexible container to cause the blood to be pumped through an outlet opening provided in the second flexible container in order to enter into the arterial system at a rate substantially equal to the normal pumping rate of the patient. A second one-way valve mechanism is provided in the aforesaid outlet opening to prevent reverse flow. The action of the flexible containers upon the blood is non-occlusive due to the pneumatic controls utilized, as well as the nature of the design of the chambers. The one-way valve mechanisms may alternatively be of a flap valve form or a form in which the closure portions of the valve are highly elastic to permit ready flow of the blood in a first direction while preventing flow in the reverse direction. In one preferred design the one-way valve structures cooperate with their associated valve mounts to provide positive reliable operation and simple straightforward removal and insertion.

Claims

1. Means for converting a low pressure fluid flow to a high pressure pulsatile flow comprising:

first and second flexible fluid receiving containers adapted to be readily expanded or compressed, each container having an inlet and an outlet port;

a first conduit connecting the inlet port of said second container to the outlet port of said first container;

one-way valve means mounted within said first conduit;

means connecting the inlet port of said first container to receive a low pressure fluid flow;

second conduit means connected to said second container outlet port for delivering the output flow of said second container;

first and second chambers respectively enclosing said first and second flexible containers;

means for maintaining the pressure in said first chamber at a predetermined constant level;

actuator means for alternately pressurizing and depressing said second chamber at an adjustable predetermined rate to urge fluid delivered to said second flexible container from said first flexible container outwardly through said second conduit in a pulsatile manner.

2. The device of claim 1 wherein said one-way valve means includes means adapted to permit fluid flow from said first to said second flexible container while preventing fluid flow in the reverse direction.

3. The device of claim 1 further comprising:

second one-way valve means mounted within said second conduit means for permitting fluid flow from said second flexible container while preventing fluid flow in the reverse direction.

4. The device of claim 1 wherein said valve means is comprised of a pair of flap members diagonally aligned within said first conduit means to form a V-shaped configuration when closed whereby said flaps are curved near their free ends to cause engagement therebetween only in the marginal region of said flap free ends in the presence of reverse fluid flow.

5. The device of claim 1 wherein said valve means is comprised of a plurality of arcuate shaped flap members diagonally aligned within said first conduit means to form a dome-shaped configuration when closed, whereby said flaps are provided with V-shaped flanges along their free ends to cause engagement therebetween only in the marginal region of said flap flanges in the presence of reverse fluid flow.

6. The device of claim 1 wherein said flexible conduits are each formed from a pair of thin sheets of a flexible material whose marginal engaging portions are joined by a suitable aDhesive means to air-tightly seal said containers as well as defining their perimeters.

7. Means for converting a low pressure fluid flow to a high pressure pulsatile flow comprising:

first and second chambers;

a flexible membrane in each of said chambers dividing each chamber into a fluid and non-fluid receiving compartment;

the fluid receiving compartments each having an inlet and an outlet port;

a first conduit connecting the inlet port of one of said fluid receiving compartments to the outlet port of the remaining fluid receiving compartment;

one-way valve means mounted within said first conduit;

input means connecting the inlet port of said one of said fluid receiving compartments to receive a low pressure fluid flow;

second conduit means connected to the outlet port of the remaining one of said fluid receiving compartments for delivering the output fluid flow of said second container;

means coupled to the non-fluid receiving compartment of said first chamber for maintaining the pressure therein at a predetermined constant level;

means coupled to the non-fluid receiving compartment of said second chamber for alternately pressurizing and depressurizing the non-fluid receiving compartment of said second chamber at an adjustable predetermined rate to urge fluid delivered thereto from the fluid receiving compartment of said first chamber outwardly through said second conduit in a pulsatile manner.

8. The device of claim 7 wherein said flexible membranes are formed of a flexible non-stretching material.

9. The device of claim 7 wherein the interior surface of the first chamber forming a portion of said first fluid receiving compartment has a substantially tapered configuration;

the flexible membrane of said fluid receiving compartment being incapable of engaging the entire surface area of said tapered surface.

10. The device of claim 7 wherein said one-way valve means includes means adapted to permit fluid flow from said first to said second chamber fluid receiving compartment flexible container while preventing fluid flow in the reverse direction.

11. The device of claim 7 further comprising:

second one-way valve means mounted within said second conduit means for permitting fluid flow from said second chamber fluid receiving compartment while preventing fluid flow in the reverse direction.

12. The device of claim 7 wherein said valve means is comprised of a plurality of arcuate shaped flap members diagonally aligned within said first conduit means to form a dome-shaped configuration when closed, whereby said flaps are provided with V-shaped flanges along their free ends to cause engagement therebetween only in the marginal region of said flap flanges in the presence of reverse fluid flow.

13. The device of claim 9 wherein the outlet port of said first chamber fluid receiving compartment is positioned at the apex of said tapered interior surface;

said tapered interior surface being provided with an annular shaped rim projecting from said surface at a location intermediate said apex and said membrane for cooperating with said member to isolate the input connecting means from said second conduit means when the second conduit means exerts a negative pressure upon the first chamber fluid receiving compartment.

14. The device of claim 1 including means responsive to the nearly total collapse of said first flexible container for deactivating said actuator means.

15. The device of claim 7 wherein said means for maintaining the pressure in the non-fluid receiving compartment of said first container includes means for regulating the pressure level in said first container in inverse proportion to the amount of blood in said first container.

16. The device of claim 15 wherein said regulating means further comprises an adjustable clamp provided in the inlet part of said first fluid receiving container.

17. The device of claim 16 further comprising plunger means having a first end resting upon the mEmbrane of said container and a second end extending outwardly from the non-fluid receiving compartment of said first container whereby the length of said second end extending beyond said first chamber is employed to determine the adjustment of said adjustable clamp.

18. The device of claim 15 wherein said pressure regulating means is further comprised of plunger means having a first end resting on the membrane of said first container and a second end extending outwardly from said first container;

said plunger means having a first opening at said second end communicating with a second opening at a point intermediate the first and second ends thereof whereby said second opening is sealed by said first container when the level of fluid in said first container is high and whereby said second opening communicates with the interior of said first chamber when the fluid level in said first container is low.