Dilator with expandable member

1. A method, comprising:

inserting a dilator and sheath access assembly into a patient, the assembly having a first conduit, a member coaxially surrounding a first section of the first conduit and capable of expansion, and a second conduit coaxially surrounding a second section of the first conduit, the first conduit having a distal end portion and a proximal end portion, the proximal end portion of the first conduit having a coupling member, the second conduit having a distal end portion and a proximal end portion, the proximal end portion of the second conduit having a coupling member, the inserting including inserting the first conduit and the second conduit into the patient while the second conduit coaxially surrounds the second section of the first conduit and the coupling member of the first conduit is coupled to the coupling member of the second conduit;

advancing the assembly through a body vessel to dilate tissue of the body vessel;

expanding, without removal of the assembly from the body vessel, the member to alleviate a blockage in the body vessel;

applying, after the expanding, a force in a proximal direction by pulling the assembly such that the member becomes lodged within a renal pelvis of a kidney of the patient to verify placement of the assembly;

decoupling the coupling member of the first conduit from the coupling member of the second conduit, the decoupling includes moving a tab of the coupling member of the first conduit towards a longitudinal axis of the dilator and sheath access assembly such that the tab disengages a portion of the coupling member of the second conduit; and

retracting the first conduit from the body vessel such that the second conduit remains in the body vessel.

2. The method of claim 1 , wherein the first conduit comprises a tapered tip.

3. The method of claim 1 , wherein the member comprises a balloon.

4. The method of claim 1 , further comprising:

unexpanding the member; and

advancing the assembly beyond the blockage.

5. The method of claim 1 , wherein the blockage is at least one of a constriction of the ureteral orifice, a sphincter, a stone, or a tumor.

6. The method of claim 1 , further comprising placing, before the inserting the assembly, a guide wire into the body vessel, the guide wire extending through the first conduit when the assembly is advanced through the body vessel.

7. The method of claim 1 , further comprising:

unexpanding the member;

advancing the assembly distally to a predetermined destination within the body vessel; and

expanding the member.

8. The method of claim 1 , further comprising:

inserting a tool into the body vessel via the second conduit.

9. The method of claim 1 , wherein the expanding includes expanding the member via an inflation lumen defined by a sidewall of the first conduit.

10. A method, comprising:

inserting a guide wire into a body of a patient;

after the inserting a guide wire, inserting a dilator and sheath access assembly into a patient, the assembly having a first conduit, a member coaxially surrounding a first section of the first conduit and capable of expansion, and a second conduit coaxially surrounding a second section of the first conduit, the first conduit having a proximal end portion and a distal end portion, the proximal end portion of the first conduit having a coupling member, the second conduit having a proximal end portion and a distal end portion, the proximal end portion of the second conduit having a coupling member;

advancing the assembly distally to a location within a renal pelvis of the patient while the coupling member of the first conduit is coupled to the coupling member of the second conduit;

expanding the member while the coupling member of the first conduit is coupled to the coupling member of the second conduit; and

Applying a force in a proximal direction by pulling the assembly to very placement of the assembly;

wherein the member becomes lodged within the renal pelvis of the patient in response to the force.

11. The method of claim 10 , wherein the first conduit comprises a tapered tip.

12. The method of claim 10 , wherein the member comprises a balloon.

13. The method of claim 10 , wherein the first conduit is removably coupled to the second conduit, the method further comprising:

decoupling, after the applying, the coupling member of the first conduit from the coupling member of the second conduit; and

retracting the first conduit from the body vessel such that the second conduit remains in the body of the patient.

14. The method claim of 13 , wherein the decoupling includes moving a tab of the coupling member of the first conduit such that the tab disengages a portion of the coupling member of the second conduit.

15. The method of claim 10 , wherein the first conduit is removably coupled to the second conduit, the method further comprising:

unexpanding the member;

decoupling, after the applying, the coupling member of the first conduit from the coupling member of the second conduit;

retracting the first conduit from the renal pelvis such that the second conduit remains in the body of the patient; and

inserting a tool into the body of the patient via the second conduit.

16. The method of claim 10 , wherein the member is expanded without removal of the assembly from the body of the patient.

17. The method of claim 10 , wherein the guide wire is configured to extend through the first conduit when the assembly is advanced within the body of the patient.

18. The method of claim 10 , wherein the expanding includes expanding the member via an inflation lumen defined by a sidewall of the first conduit.

19. A method, comprising:

inserting a dilator and sheath access assembly into a ureter of a patient, the assembly having a first conduit, a member coaxially surrounding a first section of the first conduit and capable of expansion, and a second conduit coaxially surrounding a second section of the first conduit, the first conduit having a proximal end portion and a distal end portion, the proximal end portion of the first conduit having a coupling member, the second conduit having a proximal end portion and a distal end portion, the proximal end portion of the second conduit having a coupling member;

advancing the assembly through the ureter to dilate tissue of the ureter while the coupling member of the first conduit is coupled to the coupling member of the second conduit;

expanding at a first time, while the coupling member of the first conduit is coupled to the coupling member of the second conduit and without removal of the assembly from the ureter, the member to alleviate a blockage in the ureter; and

applying a force in a proximal direction by pulling the assembly such that the member becomes lodged within a renal pelvis of a kidney of the patient.

20. The method of claim 19 , further comprising:

unexpanding, at a second time after the first time, the member;

advancing the assembly distally to the renal pelvis of the patient; and

expanding the member at a third time after the second time, without removal of the assembly from the ureter.

21. The method of claim 19 , further comprising:

unexpanding, at a second time after the first time, the member;

advancing the assembly distally to a renal pelvis of a kidney of the patient;

expanding the member at a third time after the second time, without removal of the assembly from the ureter;

unexpanding, at a fourth time after the third time, the member; and

retracting the first conduit through the ureter such that the second conduit remains in the ureter.

22. The method of claim 19 , wherein the expanding at a first time includes expanding the member via an inflation lumen defined by a sidewall of the first conduit.