Wound therapy device

• US 6,695,823 B1
• Filed: 04/07/2000
• Issued: 02/24/2004
• Est. Priority Date: 04/09/1999
• Status: Expired due to Term

• Current Assignee: KCI Licensing Incorporated (3M Company)
• Original Assignee: KCI Licensing Incorporated (3M Company)
• Inventors: Lina, Cesar Z., Johnson, Royce, Heaton, Keith
• Primary Examiner(s): Lo, Weilun
• Assistant Examiner(s): Truong, Linh
• Application Number:
  US09/545,339
• Time in Patent Office: 1,418 Days
• Field of Search: 604/313, 604/305, 604/304, 604/308, 604/289, 602/43, 602/47, 602/53-54
• US Class Current: 604/304
• CPC Class Codes: A61F 13/0203 with fluid retention members
• CPC Class Codes: A61F 13/05 specially adapted for use with sub-pressure or over-pressure therapy, wound drainage or wound irrigation, e.g. for use with negative-pressure wound therapy [NPWT]
• CPC Class Codes: A61F 2013/00174 possibility of applying pressure
• CPC Class Codes: A61F 2013/00536 for draining or irrigating wounds
• CPC Class Codes: A61F 2013/0054 for deep wounds
• CPC Class Codes: A61F 2013/0091 with disinfecting or anaesthetics means, e.g. anti-mycrobic
• CPC Class Codes: A61F 2013/00927 with biological activity, e.g. enzymes for debriding wounds or others, collagen or growth factors
• CPC Class Codes: A61M 1/72 Cassettes forming partially or totally the fluid circuit
• CPC Class Codes: A61M 1/74 Suction control underwater drainage A61M1/61
• CPC Class Codes: A61M 1/784 by filtering, sterilising or disinfecting the exhaust air, e.g. swellable filter valves
• CPC Class Codes: A61M 1/915 Constructional details of the pressure distribution manifold
• CPC Class Codes: A61M 1/962 having pumping means on the suction site, e.g. miniature pump on dressing or dressing capable of exerting suction
• CPC Class Codes: A61M 1/982 with means for detecting level of collected exudate
• CPC Class Codes: A61M 2205/123 with incorporated reservoirs
• CPC Class Codes: A61M 2205/126 with incorporated membrane filters
• CPC Class Codes: A61M 2205/3317 Electromagnetic, inductive or dielectric measuring means
• CPC Class Codes: A61M 2205/3351 Controlling upstream pump pressure
• CPC Class Codes: A61M 2205/3382 Upper level detectors

Abstract

A wound closure apparatus having a housing that contains a vacuum pump and a chamber for holding a disposable wound fluid collection canister. The canister resides within the chamber and connects at an outlet with the vacuum pump at an inlet with a porous wound pad. The pad is placed over or within a wound and adhesively secured thereto. When the vacuum pump activates, it evacuates air from the canister resulting in wound fluids flowing from the wound into the canister. Due to the negative effect that a vacuum can impose on tissue when granulation tissue is pulled into the pad, the pad contains multiple pore sizes to prevent granulation tissue from migrating into the pad. The pad has an outer surface adjacent the wound with pore sizes of a diameter of approximately 100 microns or less to prevent tissue from growing into the pad and is treated for biocompatibility.

Claims

1. A method of using a therapeutic apparatus for stimulating the healing of wounds in mammals comprising the steps of:

inserting a porous pad into or on said wound such that said porous pad is in contact with said wound, wherein said porous pad has at least a partial outer surface and an inner body, said outer surface being adapted for contact with a surface of said wound with small first pores no larger than about 100 microns in diameter to enhance biocompatibility;

securing said porous pad within said wound with a dressing cover to maintain a negative pressure at the site of said wound;

generating a negative pressure at said wound through said porous pad; and

collecting fluids from said wound through said porous pad.