Apparatus and method for deep vein thrombosis prophylaxis

1. An apparatus for promoting venous circulation in a lower extremity of a patient comprising:

a gas source;

a bladder assembly comprising a first bladder coupled to the gas source by a first fluid path and a second bladder coupled to the gas source by a second fluid path, wherein first bladder encircles the second bladder, the bladder assembly being removably mounted to an insole of a patient's footwear;

a controller operably coupled to the gas source and configured to control flow of gas from the gas source to periodically commence inflation of the first bladder followed by commencement of inflation of the second bladder, the controller being removably secured to the patient's footwear.

2. The apparatus of claim 1 , further comprising:

a housing, the gas source and controller mounted within the housing; and

a fastener secured to the housing.

3. The apparatus of claim 2 , wherein the fastener comprises a resilient clip.

4. The apparatus of claim 3 , wherein the fastener further comprises a first magnet secured to the resilient clip and a second magnet secured to the housing opposite the first magnet.

5. The apparatus of claim 1 , further comprising a user interface in data communication with the controller.

6. The apparatus of claim 5 , wherein the user interface is configured to receive frequency adjustments and pressure adjustments.

7. The apparatus of claim 6 , wherein the controller is configured to allow pressure adjustments only within a predetermined pressure range and to allow frequency adjustments only within a predetermined frequency range.

8. The apparatus of claim 7 , wherein the predetermined pressure range is 65 to 100 mmhg and wherein the predetermined frequency range is once every two to five minutes.

9. The apparatus of claim 1 , wherein the gas source comprises a first compressor coupled to the first fluid path and a second compressor coupled to the second fluid path; and

wherein the controller is operably coupled to the first and second compressors and configured to selectively and independently turn on the first and second compressors to control inflation of the first and second bladders.

10. The apparatus of claim 1 , wherein the gas source comprises a gas reservoir and wherein the first fluid path includes a first electrically controlled valve and the second fluid path includes a second electrically controlled valve; and wherein the controller is operably coupled to the first and second electrically controlled valves and configured to control opening and closing of the first and second electrically controlled valves.

11. The apparatus of claim 10 , further comprising a first electrically controlled relief valve in fluid communication with the first fluid path at a point between the first electrically controlled valve and the first bladder and a second electrically controlled relief valve in fluid communication with the second fluid path at a point between the second electrically controlled valve and the second bladder;

wherein the controller is operably coupled to the first and second electrically controlled relief valves and configured to control opening and closing of the first and second electrically controlled relief valves to cause deflation of the first and second bladders.

12. The apparatus of claim 1 , wherein the bladder assembly is sized to occupy an instep of the patient's footwear.

13. The apparatus of claim 1 , wherein the controller is configured to control the gas source effective to:

commence inflating the first bladder following a first wait period after a previous inflation of the first bladder;

commence inflating the second bladder following a second wait period after commencement of inflation of the first bladder;

maintain the first and second bladder in an inflated state for a third wait period; and

permit deflation of the first bladder and second bladder.

14. The apparatus of claim 1 , wherein the gas source comprises a compressor and wherein the first fluid path includes a first electrically controlled valve and the second fluid path includes a second electrically controlled valve, the controller being operably coupled to the first and second electrically controlled valves and configured to control opening and closing of the first and second electrically controlled valves.

15. A method for promoting venous circulation in a lower extremity of a patient comprising:

positioning a bladder assembly over an insole of a patient's footwear, said bladder assembly comprising a first bladder and a second bladder, wherein the second bladder completely encircling the first bladder in a plane parallel to the insole of the patient's footwear periodically performing:

commencing inflation of the first bladder;

commencing inflation of the second bladder following commencement of inflation of the first bladder and prior to deflation of the first bladder; and

permitting deflation of the first and second bladders; and

removing the bladder assembly and a controller, configured to control flow of gas from a gas source to the bladder assembly, from the patient's footwear.

16. The method of claim 15 , wherein commencing inflation of the first bladder comprises actuating a first valve located in a fluid path between a gas source and the first bladder; and wherein commencing inflation of the second bladder comprises actuating a second valve located in a fluid path between the gas source and the second bladder.

17. The method of claim 16 , wherein the gas source is a compressor.

18. The method of claim 17 , wherein permitting deflation of the first and second bladders comprises turning off the compressor while maintaining the first and second valves in an open state permitting fluid flow between the compressor and the first and second bladders.

19. The method of claim 16 , wherein the gas source is a reservoir of compressed gas.

20. The method of claim 15 , further comprising maintaining both the first and second bladders in an inflated state for a first wait period and permitting deflation of the first bladder and second bladder following the first wait period.

21. The method of claim 15 , wherein commencing inflation of the first bladder and commencing inflation of the second bladder include powering a compressor in fluid communication with the first and second bladders.

22. The method of claim 15 , wherein the bladder assembly is in fluid communication with a gas source, the gas source operably coupled to a controller configured to control fluid flow from the gas source, the gas source and controller mounted within a housing, the method further comprising removably coupling the housing to the footwear.

23. The method of claim 22 , wherein coupling the housing to the footwear comprises capturing a portion of the footwear by means of a clip secured to the housing.

24. An apparatus for promoting venous circulation in a lower extremity of a patient comprising:

a gas source;

a bladder assembly comprising a first bladder coupled to the gas source by a first fluid path and a second bladder coupled to the gas source by a second fluid path, wherein first bladder completely encircles the second bladder in a plane parallel to an insole of a patient's footwear;

a controller operably coupled to the gas source and configured to control flow of gas from the gas source to periodically commence inflation of the first bladder followed by commencement of inflation of the second bladder.

25. The apparatus of claim 24 , further comprising:

a housing, the gas source and controller mounted within the housing; and

a fastener secured to the housing.

26. The apparatus of claim 25 , wherein the fastener comprises a resilient clip.

27. The apparatus of claim 26 , wherein the fastener further comprises a first magnet secured to the resilient clip and a second magnet secured to the housing opposite the first magnet.

28. The apparatus of claim 24 , further comprising a user interface in data communication with the controller.

29. The apparatus of claim 28 , wherein the user interface is configured to receive frequency adjustments and pressure adjustments.

30. The apparatus of claim 29 , wherein the controller is configured to allow pressure adjustments only within a predetermined pressure range and to allow frequency adjustments only within a predetermined frequency range.

31. The apparatus of claim 30 , wherein the predetermined pressure range is 65 to 100 mmhg and wherein the predetermined frequency range is once every two to five minutes.

32. The apparatus of claim 24 , wherein the gas source comprises a gas reservoir and wherein the first fluid path includes a first electrically controlled valve and the second fluid path includes a second electrically controlled valve; and wherein the controller is operably coupled to the first and second electrically controlled valves and configured to control opening and closing of the first and second electrically controlled valves.

33. The apparatus of claim 32 , further comprising a first electrically controlled relief valve in fluid communication with the first fluid path at a point between the first electrically controlled valve and the first bladder and a second electrically controlled relief valve in fluid communication with the second fluid path at a point between the second electrically controlled valve and the second bladder;

wherein the controller is operably coupled to the first and second electrically controlled relief valves and configured to control opening and closing of the first and second electrically controlled relief valves to cause deflation of the first and second bladders.

34. The apparatus of claim 24 , wherein the bladder assembly is sized to occupy an instep of the patient's footwear.

35. The apparatus of claim 24 , wherein the controller is configured to control the gas source effective to:

commence inflating the first bladder following a first wait period after a previous inflation of the first bladder;

commence inflating the second bladder following a second wait period after commencement of inflation of the first bladder;

maintain the first and second bladder in an inflated state for a third wait period; and

permit deflation of the first bladder and second bladder.

36. The apparatus of claim 24 , wherein the gas source comprises a compressor and wherein the first fluid path includes a first electrically controlled valve and the second fluid path includes a second electrically controlled valve, the controller being operably coupled to the first and second electrically controlled valves and configured to control opening and closing of the first and second electrically controlled valves.

37. The apparatus of claim 24 , wherein the gas source comprises a first compressor coupled to the first fluid path and a second compressor coupled to the second fluid path; and

wherein the controller is operably coupled to the first and second compressors and configured to selectively and independently turn on the first and second compressors to control inflation of the first and second bladders.