System and method for determining a fill status of a canister of fluid in a reduced pressure treatment system

1. An apparatus for determining a fill status of a container of fluid in a tissue treatment system, the apparatus comprising:

a sensing device configured to sense a reduced pressure in a source conduit;

a valve configured to release the reduced pressure in the source conduit; and

a processing unit in communication with the sensing device and the valve, and

configured to:

measure a decay of the reduced pressure in the source conduit if the valve releases the reduced pressure; and

determine from the decay a fill status of the container.

2. The apparatus of claim 1 , wherein the sensing device further comprises a flow sensor in communication with the source conduit.

3. The apparatus of claim 1 , wherein the sensing device further comprises a pressure sensor in communication with the source conduit.

4. The apparatus of claim 1 , wherein the processing unit further comprises a timer to measure an amount of time it takes for pressure in the source conduit to reach a selected pressure threshold.

5. The apparatus of claim 4 , wherein the processing unit is further configured to:

determine a pressure attained within the source conduit following the selected amount of time; and

determine the fill status of the container based on the pressure attained.

6. The apparatus of claim 1 , wherein the fill status indicates whether the container is full or is not full.

7. The apparatus of claim 1 , wherein:

the valve selectively releases the reduced pressure from at least a portion of the source conduit; and

the decay of reduced pressure is determined in the portion of the source conduit.

8. The apparatus of claim 1 , wherein the valve comprises an electrically or mechanically-actuated valve.

9. The apparatus of claim 1 , further comprising a container-full alarm in communication with the processing unit and configured to alert a user if the container is full.

10. The apparatus of claim 1 , further comprising:

a second valve between a tissue site and the container configured to be closed while the reduced pressure is released;

wherein an empty volume of the container is determined based on the decay.

11. The apparatus of claim 10 , wherein the empty volume is monitored to determine a fluid flow rate from the tissue site.

12. The apparatus of claim 1 , wherein the source conduit is adapted to fluidly connect a reduced-pressure source to the container.

13. The apparatus of claim 1 , wherein the processing unit is further configured to determine whether a blockage exists within the source conduit.

14. An apparatus for reduced-pressure therapy, the apparatus comprising:

a sensing device configured to sense a reduced pressure in a source conduit; and

a processing unit in communication with the sensing device and configured to:

measure the reduced pressure applied to the source conduit;

measure a decay of the reduced pressure as the reduced pressure is released; and

determine from the measured decay a fill status of a container in fluid communication with the source conduit.

15. The apparatus of claim 14 , wherein the fill status indicates whether the container is full or is not full.

16. The apparatus of claim 14 , wherein the processing unit is further configured to;

set a pressure threshold below the reduced pressure;

upon release of the reduced pressure, measure the time for the container to attain the pressure threshold; and

determine the fill status of the container based on the measured time.

17. The apparatus of claim 14 , wherein the sensing device is positioned along the conduit between a tissue site and a reduced-pressure source.

18. The apparatus of claim 17 , wherein the sensing device is positioned on the source conduit between the reduced-pressure source and the container.

19. The apparatus of claim 14 , further comprising a valve in communication with the source conduit.

20. The apparatus of claim 19 , wherein the valve is configured to release the reduced pressure.

21. The apparatus of claim 14 , wherein determining a fill status includes determining a fill level.

22. The apparatus of claim 21 , wherein the processing unit is further configured to alert a user that the container is full if the fill level of the container indicates a full container.

23. The apparatus of claim 14 , wherein the processing unit is further configured to differentiate between a full container and a blocked source conduit.

24. The apparatus of claim 23 , wherein the processing unit is further configured to signal a first alarm for the full container and signaling a second alarm for the blocked source conduit.

25. The apparatus of claim 14 , wherein the processing unit is further configured to determine a decay of the reduced pressure over a selected amount of time.

26. The apparatus of claim 25 , wherein the processing unit is further configured to distinguish between a full container and a blocked conduit based on a rate of decay of the reduced pressure.

27. The apparatus of claim 14 , wherein the source conduit is adapted to fluidly connect a reduced-pressure source to the container.

28. The apparatus of claim 14 , wherein the processing unit is further configured to determine whether a blockage exists within the conduit.

29. An apparatus for determining a fill status of a container, the apparatus comprising:

a means for detecting whether a blockage condition exists between a reduced-pressure source and a tissue site;

a means for determining a pressure decay in a conduit fluidly connecting the reduced-pressure source to the tissue site after the blockage condition is detected; and

a means for determining whether the container is full based on pressure decay data.

30. The apparatus of claim 29 , further comprising a means for signaling that a blockage exists between the container and a tissue site based on a determination that the container is not full.