Fistula catheter

1. A fistula catheter to be disposed in a fistula of a patient, comprising:

an extracorporeal fixing part configured to be disposed on an abdominal wall surface-side of the fistula;

a supply tube comprising a tubular element joined to the extracorporeal fixing part, and having a tip-end section, a main lumen, and a sub-lumen in a peripheral wall thereof; and

an intracorporeal fixing part at an outer periphery of the supply tube and proximate the tip-end section, the intracorporeal fixing part comprising an inner balloon and an outer balloon outside of the inner balloon, a first one-way valve disposed between the sub-lumen and the inner balloon, and a second one-way valve disposed between the sub-lumen and the outer balloon, the inner balloon in communication with the sub-lumen through the first one-way valve, and the outer balloon in communication with the sub-lumen through the second one-way valve.

2. The fistula catheter according to claim 1 , further comprising a first injection port in the sub-lumen and a second injection port in the sub-lumen, wherein the first one-way valve is disposed in the first injection port and the second one-way valve is disposed in the second injection port.

3. The fistula catheter according to claim 2 , wherein the outer balloon is comprised of a material that is more stretchable than the inner balloon material comprising the inner balloon.

4. The fistula catheter according to claim 3 , wherein the inner balloon has fixed inflation size.

5. The fistula catheter according to claim 4 , wherein the inner balloon and the outer balloon are each fixed to the supply tube by adhesive.

6. The fistula catheter according to claim 3 , wherein the first one-way valve and the second one-way valve are configured to operate at pressures different from one another such that the inner balloon is inflated via the sub-lumen in advance of the outer balloon being inflated via the sub-lumen.

7. The fistula catheter according to claim 1 , wherein, when each of the inner balloon and the outer balloon is inflated, a space is formed therebetween.

8. The fistula catheter according to claim 1 , wherein each of the first balloon and the second balloon are inflated via the sub-lumen.

9. The fistula catheter according to claim 1 , wherein the first one-way valve is sized and configured to open at first pressure to permit fluid flow from the sub-lumen to inflate the inner balloon,

wherein the second one-way valve is sized and configured to open at second pressure to permit fluid flow from the sub-lumen to inflate the outer balloon, and

wherein the first pressure is a different pressure than the second pressure.

10. The fistula catheter according to claim 1 , wherein the first pressure is lower than the second pressure.

11. The fistula catheter according to claim 1 , wherein the first one-way valve and the second one-way valve are configured to operate at pressures different from one another such that the inner balloon is inflated via the sub-lumen in advance of the outer balloon being inflated via the sub-lumen.