Wound therapy device and related methods

1. A wound closure apparatus to promote tissue healing at a wound, the apparatus comprising:

a porous pad adapted to be positioned at the wound;

a suction pump in fluid communication with the porous pad to provide a negative pressure to the porous pad, the suction pump being disposed within a housing;

a canister fluidly connected between the porous pad and the suction pump to collect fluids drawn from the wound by the suction pump, the canister being removably received by a recess in the housing;

a wound cover positioned over the porous pad to secure the porous pad at the wound; and

a switch providing a signal indicating that the canister properly resides within the recess when the switch is pressed.

2. The apparatus of claim 1 , wherein fluid communication is provided between the porous pad and the canister by a tube.

3. The apparatus of claim 2 , wherein the tube is fitted as an interference fit into an interior portion of the porous pad.

4. The apparatus of claim 1 , wherein the porous pad comprises a polymer foam having interconnecting cells.

5. The apparatus of claim 1 , wherein the porous pad is a polyurethane reticulated foam.

6. The apparatus of claim 1 , wherein the porous pad comprises a reticulated foam having at least 90% interconnecting cells.

7. The apparatus of claim 1 , wherein the porous pad comprises a reticulated foam having at least 95% interconnecting cells.

8. The apparatus of claim 1 further comprising a delay circuit adapted to silence an alarm associated with an improper operating condition.

9. The apparatus of claim 1 , wherein the wound cover includes an adhesive in a peripheral area of the wound cover.

10. The apparatus of claim 9 , wherein the peripheral area with the adhesive extends beyond a periphery of the porous pad for adhering to intact skin around the wound.

11. The apparatus of claim 1 further comprising a latch securing the canister in the recess in the housing.

12. The apparatus of claim 1 , wherein the canister includes a transparent window.

13. A wound closure apparatus to promote tissue healing at a wound, the apparatus comprising:

a porous pad adapted to be positioned at the wound;

a suction pump in fluid communication with the porous pad to provide a negative pressure to the porous pad;

a canister fluidly connected between the porous pad and the suction pump to collect fluids drawn from the wound by the suction pump;

a wound cover positioned over the porous pad to secure the porous pad at the wound; and

a bleed valve to vent negative pressure between the suction pump and the canister when the suction pump is deactivated.

14. The apparatus of claim 13 , wherein the bleed valve permits release of negative pressure during intermittent operation of the suction pump.

15. The apparatus of claim 13 , wherein bleed valve prevents overpressurization of negative pressure during operation of the suction pump.

16. The apparatus of claim 13 , wherein the bleed valve comprises an orifice.

17. The apparatus of claim 16 , wherein the orifice is 0.5 mm in diameter.

18. The apparatus of claim 13 , wherein:

the suction pump is disposed within a housing; and

the bleed valve is disposed outside of the housing to facilitate un-clogging of blockages.

19. The apparatus of claim 13 further comprising:

a tube to fluidly connect the canister and the suction pump; and

a tank fluidly connected to the tube to act as a damper to pressure changes in the tube.

20. The apparatus of claim 19 further comprising:

a transducer fluidly connected to the tube to measure a pressure in the tube.

21. The apparatus of claim 13 , wherein fluid communication is provided between the porous pad and the canister by a tube.

22. The apparatus of claim 21 , wherein the tube is fitted as an interference fit into an interior portion of the porous pad.

23. The apparatus of claim 13 , wherein the porous pad comprises a polymer foam having interconnecting cells.

24. The apparatus of claim 13 , wherein the porous pad is a polyurethane reticulated foam.

25. The apparatus of claim 13 , wherein the porous pad comprises a reticulated foam having at least 90% interconnecting cells.

26. The apparatus of claim 13 , wherein the porous pad comprises a reticulated foam having at least 95% interconnecting cells.

27. The apparatus of claim 13 further comprising a delay circuit adapted to silence an alarm associated with an improper operating condition.

28. The apparatus of claim 13 , wherein the wound cover includes an adhesive in a peripheral area of the wound cover.

29. The apparatus of claim 28 , wherein the peripheral area with the adhesive extends beyond a periphery of the porous pad for adhering to intact skin around the wound.

30. The apparatus of claim 13 , wherein the canister includes a transparent window.

31. The apparatus of claim 13 further comprising a sensor for detecting when the canister is substantially full with fluid, the sensor being associated with the suction pump to discontinue application of the negative pressure when a substantially full condition of the canister is detected.

32. The apparatus of claim 31 , wherein the sensor comprises a capacitance sensor, the sensor being arranged to sense a change of capacitance as the canister fills with fluid.

33. The apparatus of claim 13 further comprising a tilt sensor associated with the suction pump to discontinue application of negative pressure when tilting of the canister greater than a predetermined angle is detected.

34. The apparatus of claim 33 , wherein the predetermined angle is approximately 45°.

35. The apparatus of claim 13 further comprising a sensor for detecting a variance greater than a predetermined angle of an axis of the canister.