METHODS AND DEVICES TO INDUCE CONTROLLED ATELECTASIS AND HYPOXIC PULMONARY VASOCONSTRICTION

Abstract

Lung conditions are treated by implanting a flow restrictor in a passageway upstream from a diseased lung segment. The restrictor will create an orifice at the implantation site which inhibits air exchange with the segment to induce controlled atelectasis and/or hypoxia. Controlled atelectasis can induce collapse of the diseased segment with a reduced risk of pneumothorax. Hypoxia can promote gas exchange with non-isolated, healthy regions of the lung even in the absence of lung collapse.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B illustrate a first embodiment of a flow restrictor constructed in accordance with the principles of the present invention having flow apertures in a reduced diameter portion thereof.

FIGS. 2A-2D illustrate a second embodiment of a flow restrictor constructed in accordance with the principles of the present invention, wherein flow apertures are located in a different location than illustrated in FIGS. 1A and 1B.

FIG. 3 illustrates a third embodiment of a flow restrictor comprising a silicone body having an orifice tube therein.

FIG. 4 illustrates a fourth embodiment of a flow restrictor constructed in accordance with the principles of the present invention, which comprises a continuous body structure having windows formed in one end thereof.

FIGS. 5A and 5B illustrate a fifth embodiment of a flow restrictor constructed in accordance with the principles of the present invention having flow channels formed in an outer surface thereof.

FIG. 6 illustrates a sixth embodiment of a flow restrictor constructed in accordance with the principles of the present invention having an internal tapered flow restrictive orifice.

FIG. 7 illustrates a seventh embodiment of a flow restrictor constructed in accordance with the principles of the present invention having an internal tube which provides flow resistance.

FIGS. 8A and 8B illustrate an eighth embodiment of a flow restrictor constructed in accordance with the principles of the present invention, wherein the flow restrictor has a bell shape and is constructed of a gas penetrable braid.

FIG. 9 illustrates a ninth embodiment of a flow restrictor constructed in accordance with the principles of the present invention, wherein the flow restrictor comprises a cylindrical body formed of a gas penetrable braid.

FIG. 10 is an anatomical diagram illustrating the lobar structure of the lungs of a patient.

FIG. 11 illustrates the trans-esophageal endobronchial placement of a flow restrictor delivery catheter in an airway leading to a diseased lung region.

FIG. 12 illustrates placement of a flow restrictor by the catheter placement device of FIG. 11.

FIGS. 13A and 13B illustrate the physiologic effect of placement of the flow restrictor at an airway leading to a diseased lung region with little or no collateral ventilation.

FIGS. 14A and 14B illustrate the physiologic response induced by placement of a flow restrictor at an airway feeding a diseased lung region which has significant collateral ventilation.

Claims

1. A method for treating a lung condition, said method comprising: implanting an air flow restrictor in an airway of the lung, wherein said restrictor reduces air flow exchange between upstream of the restrictor and downstream of the restrictor, wherein such air flow restriction induces at least one of controlled atelectasis and localized hypoxia in a treated region beyond the restriction.

2. A method as in claim 1, wherein controlled atelectasis is induced which causes collapse of the treated region downstream of the air flow restrictor.

3. A method as in claim 2, wherein the treated region collapses over a period in the range from 12 hours to 30 days.

4. A method as in claim 1, wherein localized hypoxia is induced without collapse of the treated region, wherein the hypoxia shifts blood flow away from the treated region to other regions of the lung.

5. A method as in claim 4, wherein the treated region has collateral flow channels with adjacent lung regions, wherein collateral flow channels inhibit atelectasis and collapse.

6. A method as in claim 1, wherein the volumetric rate of the restricted air flow exchange is reduced by a percentage from 10% to 99.99% of the unrestricted volumetric rate of air flow exchange.

7. A method as in claim 6, wherein the percentage is from 99% to 99.9%.

8. A method as in claim 1, wherein the restrictor includes at least one open passage which permits air flow exchange.

9. A method as in claim 8, wherein the passage consists of a single orifice.

10. A method as in claim 8, wherein the restrictor includes a plurality of passages.

11. A method as in claim 8, wherein the open passage area is in the range from 0.01% to 90% of the area of the airway where the restrictor is implanted.

12. A method as in claim 8, wherein the open passage area is in the range from 0.01 mm2 to 50 mm2.

13. A method as in claim 1, wherein implanting comprises releasing a self-expanding restrictor from a constraint so that the restrictor opens and anchors in the airway.

14. A method as in claim 13, wherein the restrictor is released from a tubular introducer.

15. A method as in claim 1, wherein the restrictor is expanded by an expansion member.

16. A bronchial flow restrictor comprising a body having at least one open passage to permit bidirectional air flow therethrough, wherein the body is adapted to be expanded and anchored within a lung airway for the control of air exchange with a downstream region of the lung.

17. A bronchial flow restrictor as in claim 16, wherein the passage consists of a single orifice.

18. A bronchial flow restrictor as in claim 16, wherein the restrictor includes a plurality of passages.

19. A bronchial flow restrictor as in claim 16, wherein the open passage area is in the range from 0.01% to 90% of the cross-sectional area of the body when expanded.

20. A bronchial flow restrictor as in claim 16, wherein the open passage area is in the range from 0.01 mm2 to 50 mm2.

21. A bronchial flow restrictor as in claim 5, wherein the at least one passage comprises a plurality of channels on the outside of the body.

22. A bronchial flow restrictor as in claim 16, wherein the body is elastic so that it can be constrained to a smaller width for introduction to the lung airway and released to self-expand and anchor at a designated location.

23. A bronchial flow restrictor as in claim 16, is malleable and expandable by application of an expansion force.

24. A bronchial flow restrictor as in claim 16, wherein the body comprises a plurality of woven elements adapted to radially self-expand and form a generally contiguous surface having a plurality of openings which provide a resistance to the bi-directional flow of air when deployed in an airway of a lung.

25. A system comprising a bronchial flow restrictor as in claim 1, and a delivery catheter adapted to deliver the bronchial flow restrictor in an airway of the lung.

26. A system as in claim 25, wherein the delivery catheter comprises an outer catheter tube and an inner pusher member, wherein the bronchial flow restrictor is receivable in a distal end of the outer catheter tube and the inner pusher member is adapted to advance and release the bronchial flow restrictor from the tube.