HK1154524A

HK1154524A - Dressing assemblies for wound treatment using reduced pressure

Info

Publication number: HK1154524A
Application number: HK11108649.5A
Authority: HK
Inventors: 小理查德‧马文‧卡紮拉; 贾斯汀‧亚历山大‧龙恩; 埃里克‧伍德森‧巴塔; 姚莉; 罗伯特‧佩顿‧威尔克斯
Original assignee: 凯希特许有限公司
Priority date: 2008-05-30
Filing date: 2009-05-29
Publication date: 2012-04-27

Abstract

A dressing assembly for use with a reduced pressure treatment system, the dressing assembly develops a directed force under reduced pressure. The directed force may be a radial force or a closing force. The dressing assembly (30) includes a shaped dressing bolster (32) having a shaped extremity (33) that is operable to evenly deliver the radial force and to distribute reduced pressure. Numerous shapes may be used for the shaped extremity. The dressing assembly may further include an over-drape (62) to assist in creating a seal over the shaped dressing bolster and against a portion of a patient's epidermis.

Description

Dressing assembly for wound treatment using reduced pressure

RELATED APPLICATIONS

The present invention claims the benefits of the concourse of the following applications according to section 119 (e) of the american code volume 35: U.S. provisional patent application serial No. 61/057,807 entitled "Reduced-pressure scientific wooden Treatment System" filed on 30.5.2008; U.S. provisional patent application Ser. No. 61/057,798 entitled "dropping Assembly For Subcutaneous group Wund treatment Using Reduce Pressure", filed on 30.5.2008; U.S. provisional patent application Ser. No. 61/057,808 entitled "See-Through, Reduced-Pressure Dressing" filed on 30.5.2008; U.S. provisional patent application Ser. No. 61/057,802 entitled "Reduced-Pressure drying Assembly For Use in Applying a cloning Force" filed on 30.5.2008; U.S. provisional patent application Ser. No. 61/057,803, entitled "Reduced-Pressure, Linear-round Treatment System, filed on 30.5.2008; U.S. provisional patent application Ser. No. 61/057,800 entitled "Reduced-Pressure, Compression System and Apparatus for use on a Current Body Part", filed on 30.5.2008; U.S. provisional patent application Ser. No. 61/057,797 entitled "Reduced-Pressure, Compression System and Apparatus for use on Breast Tissue," filed on 30.5.2008; U.S. provisional patent application Ser. No. 61/057,805 entitled "Super-Absorbent, Reduced-Pressure Wound driving and System" filed on 30.5.2008; U.S. provisional patent application Ser. No. 61/057,810 entitled "Reduced-Pressure, Compression System and Apparatus for use on a Joint" filed on 30.5.2008; U.S. provisional patent application serial No. 61/121,362 entitled "Reduced-Pressure wooden treatment System Employing an isocrotopic tear" filed on 10.12.2008; and U.S. provisional patent application sequence 61/144,067 entitled "Reduced-Pressure, Compression System and Apparatus for use on a Joint" filed on 12.1.2009. All of these provisional applications are incorporated herein by reference for all purposes.

Background

The present invention relates generally to medical treatment systems, and more particularly to reduced-pressure wound treatment systems suitable for use with surgical wounds and other tissue sites.

Physicians worldwide perform millions of exceptional surgical procedures each year. Many of these procedures are performed as open procedures, and an increasing number are performed using minimally invasive procedures (e.g., endoscopic procedures, arthroscopic procedures, and laparoscopic procedures). As an example, the american society for cosmetic and plastic surgery reports that over 450,000 liposuction procedures occurred in the united states in 2007.

Surgical procedures involve severe trauma, such as incisions, in the skin and associated tissue. In many cases, the incision is closed at the end of the procedure using mechanical means (e.g., staples or sutures), or is closed using an adhesive. Thereafter, wounds are often covered with only dry sterile bandages. Of course, there is usually not only a break at the epidermis.

Using many surgical procedures, particularly those performed with minimally invasive techniques, many fractures or lesions are below the epidermis or at the subcutaneous level. As another example, in one type of liposuction procedure, after the introduction of the tumescent fluid (saline, mild pain medication, and epinephrine), the surgeon will use a trocar and cannula with suction to remove the fatty area. In doing so, it is not uncommon for subcutaneous voids and other tissue defects to form at tissue sites that are remote from the incision in which the cannula is placed or other incisions in which the device is placed. The damaged tissue will require time and care to heal and carries a number of potential complications and risks, including edema, seroma, hematoma, additional bruising, and ecchymosis, to name a few.

To aid healing after many surgical procedures (e.g., liposuction, depending on the body part involved), a tight fitting garment or elastic compression garment may be used to fit the patient for several weeks. These tools are sometimes uncomfortable, may apply compression in a non-uniform manner, and may be difficult to put on and take off. In addition, the same patient may require many different compression garments due to edema. It would be desirable to address some or all of the disadvantages of post-surgical wound care at incisions and at damaged subcutaneous tissue.

Brief summary

Disadvantages of aspects of wound care are addressed herein by illustrative embodiments. According to one illustrative embodiment, a dressing assembly for a reduced-pressure treatment system includes a shaped dressing bolster having a first surface, a second (inward-facing) surface, and a tip. The shaped dressing bolster is formed from a medical bolster material. The tip has an inclined surface. The shaped dressing bolster is operable to evenly distribute compressive forces.

According to another illustrative embodiment, a dressing assembly for a reduced-pressure treatment system includes a shaped dressing bolster having a first surface, a second (inward-facing) surface, and a tip. The shaped dressing bolster is formed of a medical bolster material operable to distribute reduced pressure. The dressing assembly further includes an over-drape (over-drape) coupled to the first surface of the shaped dressing bolster and the distal end of the shaped dressing bolster. The shaped dressing bolster is operable to evenly distribute a compressive force that results when the shaped dressing bolster is subjected to reduced pressure.

According to another illustrative embodiment, a dressing assembly for a reduced-pressure treatment system includes a shaped dressing bolster having a shaped end, a first surface, and a second (inward-facing) surface. The dressing assembly also includes an over-drape disposed on and coupled to at least a portion of the first surface of the shaped dressing bolster. The over-drape may extend out of the shaped dressing bolster to form a drape extension having a first side and an inwardly facing second side. An adhesive perimeter strip may be coupled to the second side of the drape extension to provide a seal between the patient and the over-drape.

According to another illustrative embodiment, a dressing assembly for a reduced-pressure treatment system includes a shaped dressing bolster having a shaped end, a first surface, and a second (inward-facing) surface. The shaped dressing bolster is operable to evenly distribute compressive forces. The dressing assembly also includes an over-drape disposed on the first surface of the shaped dressing bolster, the over-drape extending out of the shaped dressing bolster over the shaped dressing bolster to form a drape extension. The drape extension has a first surface and an inwardly facing second surface. The dressing assembly also includes an inner layer having a first surface and an inwardly facing second surface. The first surface of the inner layer is at least partially coupled to a portion of the second surface of the shaped dressing bolster. The inner layer is formed with a treatment area aperture. The shaped dressing bolster is formed of a medical bolster material operable to distribute reduced pressure.

According to another illustrative embodiment, a method of manufacturing a shaped dressing bolster for a reduced pressure treatment system includes the steps of: a medical bolster material is provided and a shaped dressing bolster is formed from the medical bolster material. The shaped dressing bolster is operable to distribute reduced pressure and evenly distribute compressive forces, and is formed to have a shaped tip.

Other features and advantages of the illustrative embodiments will become apparent with reference to the drawings and detailed description that follow.

Brief Description of Drawings

A more complete understanding of the present invention may be derived by referring to the following detailed description when considered in conjunction with the accompanying drawings, wherein:

fig. 1 is a schematic perspective view of an illustrative embodiment of a reduced-pressure surgical wound treatment system shown on an incision and over damaged subcutaneous tissue;

fig. 2 is a schematic cross-section of a portion of an illustrative embodiment of a reduced-pressure surgical wound treatment system shown on intact skin and over an area of damaged subcutaneous tissue;

fig. 3 is a schematic cross-section of a portion of an illustrative embodiment of a reduced-pressure surgical wound treatment system shown positioned over a torso of a patient;

fig. 4 is a schematic cross-section of a portion of an illustrative embodiment of a reduced-pressure surgical wound treatment system shown positioned over a torso of a patient;

fig. 5 is a schematic perspective view of an illustrative embodiment of a dressing assembly;

fig. 6 is a schematic cross-section of an illustrative embodiment of the dressing assembly of fig. 5;

fig. 7 is a schematic cross-section of an illustrative embodiment of another dressing assembly;

fig. 8 is a schematic cross-section of an illustrative embodiment of another dressing assembly;

fig. 9 is a schematic perspective view of a portion of an illustrative embodiment of a dressing assembly;

fig. 10 is a schematic cross-section of an illustrative embodiment of a dressing assembly;

fig. 11 is a schematic cross-section of an illustrative embodiment of a dressing assembly;

fig. 12 is an exploded schematic perspective view of an illustrative embodiment of a dressing assembly;

fig. 13 is a schematic cross-section of an illustrative embodiment of a dressing assembly;

fig. 14 is an exploded schematic perspective view of an illustrative embodiment of a dressing assembly;

fig. 15 is a schematic perspective view of an illustrative embodiment of a dressing assembly;

fig. 16 is a cross-sectional view of a portion of the dressing assembly of fig. 15; and

fig. 17 is an exploded schematic perspective view of an illustrative embodiment of a dressing assembly.

Detailed Description

In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that logical structural, mechanical, electrical, and chemical changes may be made without departing from the spirit or scope of the present invention. The description may omit certain information known to those skilled in the art, in order to avoid detail not necessary to enable those skilled in the art to practice the invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the appended claims.

Referring now to fig. 1, a reduced-pressure system for treating tissue, such as subcutaneous tissue in an area surrounding an incision or incision, according to an illustrative embodiment is shown. As used herein, "or" does not require mutual exclusivity. The reduced-pressure system 10 is shown with the incision 12 passing through the epidermis 14 or skin and dermis 16 and into the hypodermis or subcutaneous tissue 18 in the area surrounding the incision 12. Subcutaneous tissue 18 may include many tissue types, such as adipose tissue or muscle. A damaged or destroyed or abnormal subcutaneous tissue site 20 is shown extending from the incision 12 and in this case includes a subcutaneous defect, dead space or void 22.

The damaged subcutaneous tissue 20 may result from a surgical procedure, such as liposuction. The damaged subcutaneous tissue 20 may include voids (e.g., void 22), open spaces, or various defects that may be troublesome for a number of reasons, such as allowing fluid to collect, which may lead to edema. The term "fluid" as used herein generally refers to a gas or a liquid, but may also include any other flowable material, including but not limited to gels, colloids, and foams.

The system 100 may help the injured subcutaneous tissues 20 to be brought into proximity-together or close-together-to improve healing while reducing or eliminating skin irritation. The system 100 may also generate a closing force directed at the incision 12 and may help keep the incision closed or provide support. System 100 may help minimize shear stress on deep wounds (e.g., void 22). The system 100 may also help keep the incision 12 dry, help avoid dead space formation, improve perfusion, and avoid seromas and hematoma formation. In addition, the system 100 may help minimize bruising and edema secondary to certain surgical procedures. The system 100 may provide comfort to the patient and a relatively shortened duration of time that the system 100 may need to be on the patient. Using the system 100, dressing changes can be eliminated, or the number of changes required can be minimized.

The incision 12 may be closed using any mechanical closure means, such as staples or sutures, or may be closed using an adhesive, but is shown in this illustrative embodiment as being closed using a suture 13. The reduced-pressure system 10 is generally used to treat an area, and in particular, is generally used to treat a subcutaneous tissue site 20 and tissue surrounding the subcutaneous tissue 20, although the reduced-pressure system 10 may also be used to treat a more limited area surrounding the incision 12.

The reduced-pressure system 10 includes a dressing assembly 30, the dressing assembly 30 including a shaped dressing bolster 32, a sealing subsystem 60, and a reduced-pressure subsystem 80. The reduced-pressure system 10 generates a force, which may include a vertical force or a closing force. As used in this context and herein, "vertical" means parallel to arrow 24 regardless of direction, but is shown vertically in fig. 1. The force generated in the vertical direction may be a compressive force or a lifting force. In the illustrative embodiment, the net vertical force is presented as a compressive force represented by arrow 24, and the closing force is shown by arrow 26. The compressive force 24 may be achieved at the subcutaneous tissue 20 or deeper, including at the organs. Subcutaneous tissue, as used herein, may also include deeper tissues. The compressive force 24 may be directed vertically (i.e., generally toward the centerline of the patient's body or body part or from the first side 34 to the second side 34 relative to the shaped dressing bolster 32). The compressive force 24 may reach the subcutaneous tissue. The magnitude of the vertical force 24 may be influenced by the size and shape of the shaped dressing bolster 32.

In some instances, it may be desirable to have the shaped dressing bolster 32 transmit a vertical force as the lifting force. The density and thickness of the shaped dressing bolster 32 is variable to control lift. For example, if the density of the medical bolster material is less than the density of the tissue (e.g., epidermis) at the tissue site, a lifting force may be generated. Since the relatively thick portion of the shaped dressing bolster 32 is subjected to reduced pressure, the shaped dressing bolster contracts toward the central portion from all directions. The portion of the shaped dressing bolster 32 adjacent the patient's epidermis will pull out of the patient's epidermis because the central portion is above the patient's epidermis. This creates a vertical lifting force. One portion of the shaped dressing bolster may provide a compressive force and another portion, typically the central portion, provides a lifting force relative to the patient or system.

The illustrative embodiment of fig. 1 is shown with a vertical force applying a compressive force 24. As described further below, the shaped dressing bolster 32 may be shaped and configured to allow compressive forces to be distributed fairly evenly over the patient's epidermis 14 and beneath the epidermis 14. Otherwise, if there are areas of significantly increased force compared to other areas, skin irritation may result. The reduced-pressure system 10 may also be operable to generate a closing force, i.e., a substantially tangential force toward an interior portion of the dressing assembly 30, represented by reference numeral 26. The closing force 26 remains substantially in the plane of the epidermis 14; in other words, the closing force 26 operates primarily inside the epidermis 14. In addition, the reduced-pressure system 10 is operable to deliver reduced pressure to the incision 12, which may be achieved at the level of the subcutaneous void 22, depending on the state of the incision and healing, to help approximate-bring together the tissues in the area, as well as to help remove any air or any other fluid or provide reduced-pressure therapy. The compressive force 24 may also close or assist in closing the void 22.

As used herein, "reduced pressure" generally refers to a pressure that is less than the ambient pressure at a tissue site undergoing treatment. In most cases, the reduced pressure will be less than the atmospheric pressure at which the patient is located. Alternatively, the reduced pressure may be less than the hydrostatic pressure at the tissue site. Unless otherwise indicated, the values of pressure specified herein are gauge pressures. The reduced pressure delivered may be constant or variable (uniform or random), and may be delivered continuously or intermittently. Although the terms "vacuum" and "negative pressure" may be used to describe the pressure applied to the tissue site, the actual pressure applied to the tissue site may be greater than the pressure typically associated with a complete vacuum. Consistent with the use herein, an increase in reduced or vacuum pressure generally refers to a relative decrease in absolute pressure.

The dressing assembly 30 includes a shaped dressing bolster 32 having a first side 34 and an inward (skin-facing or patient-facing) second side 36. The shaped dressing bolster 32 may be sized and shaped to substantially match the estimated area of the damaged subcutaneous tissue 20, although larger or smaller sizes may be used in different applications. The shaped dressing bolster has a peripheral edge 38. The shaped dressing bolster 32 may be manufactured from many different medical bolster materials, i.e., materials that are suitable for use in medical applications and that may be manufactured to be sterile. In one illustrative embodiment, the shaped dressing bolster 32 is manufactured from a medical bolster material that is a manifold material. The term "manifold" as used herein generally refers to a substance or structure configured to assist in applying reduced pressure to, delivering fluids to, or removing fluids from a tissue site. The manifold material typically includes a plurality of flow channels or pathways that distribute fluid provided to and removed from the tissue site around the manifold material. The flow channels or paths may be interconnected. The manifold material may be a biocompatible material capable of being placed in contact with the tissue site and distributing reduced pressure to the tissue site. Examples of manifold materials may include, for example, but are not limited to, materials having structural elements arranged to form flow channels, such as cellular foams, open cell foams, porous tissue aggregates, liquids, gels, and foams that include or cure to include flow channels.

The manifold material or medical bolster material may be porous and may be made of foam, gauze, felted mat, or any other material suitable for a particular biological application. In one embodiment, the manifold material is a porous foam and includes a plurality of interconnected cells or pores that act as flow channels. The cellular foam may be a polyurethane open cell reticulated foam, such as the GranuFoam manufactured by Kinetic conjugates Incorporated of san antonio, texasA material. Other embodiments may include "closed pores".

Typically in the range of about 400 to 600 microns, GranuFoamThe mesh of gas holes of the material helps to perform the manifold function, but other materials may be used. Medical bolster materials (e.g., GranuFoam)Material) typically has a density in the range of about 1.3-1.6lb/ft3(20.8kg/m3-25.6kg/m 3). Having a ratio of GranuFoamMaterials with high density (smaller pore size) may be desirable in some circumstances. For example, 3 having a molecular weight greater than 1.6lb/ft (25.6)kg/m3) of a density of GranuFoamMaterial or the like. As another example, GranuFoam having a density greater than 2.0lb/ft3(32kg/m3) or 5.0lb/ft3(80.1kg/m3) or even higher may be usedMaterial or the like. The higher the density of the material, the higher the compressive force that can be generated for a given reduced pressure. If foam having a density less than the tissue at the tissue site is used as the medical bolster material, a lifting force may be generated.

The medical bolster material may be a reticulated foam that is subsequently bonded to a thickness of about 1/3 a of the original thickness of the foam. Among the many possible materials, the following may be used: granufoamMaterials or FoamexIndustrial foam (www.foamex.com). In some cases, it may be desirable to add ionic silver to the foam or to add other substances (e.g., antimicrobial agents) to the medical bolster material in the micro-welding process. The medical bolster material may be isotropic or anisotropic, depending on the exact direction of the desired force during decompression. The medical bolster material may be a bioabsorbable material. A comfort layer of material may also be added between the medical bolster material and the patient.

The sealing subsystem 60 includes an over-drape 62 or drape or sealing member. The over-drape 62 may be an elastomeric material or may be any material that provides a fluid seal. By "fluid seal" or "seal" is meant a seal sufficient to maintain reduced pressure at a desired location given the reduced-pressure subsystem involved. The over-drape 62 may be, for example, an impermeable or semi-permeable elastomeric material. "elastic" means having an elastomerAnd (4) properties. The elastic material is typically a polymeric material having rubber-like properties. More specifically, most elastomers have an elongation greater than 100% and a considerable resilience. The resiliency of a material refers to the ability of the material to recover from elastic deformation. Examples of elastomers may include, but are not limited to, natural rubber, polyisoprene, styrene butadiene rubber, neoprene, polybutadiene, nitrile rubber, butyl rubber, ethylene propylene diene monomer, chlorosulfonated polyethylene, polysulfide rubber, polyurethane, EVA film, copolyester, and silicone. Specific examples of over-drape materials include silicone drapes, 3M TegadermA drape, an acrylic drape (such as that available from Avery Dennison), or a incise drape (incise drape).

The over-drape 62 may be coupled to the shaped dressing bolster 32. If coupling is desired, coupling can occur in a number of ways. An adhesive, such as an acrylic adhesive, a silicone adhesive, a hydrogel, a hydrocolloid, or the like, may be used to couple the over-drape 62 and the shaped dressing bolster 32. The over-drape 62 and shaped dressing bolster 32 may be bonded using any technique, including but not limited to welding (e.g., ultrasonic welding or RF welding), bonding, adhesives, cements, and the like. The over-drape 62 and the shaped dressing bolster 32 may be partially coupled, fully coupled, or not coupled at all. Structures may be added to the bonds to make the over-drape 62 appear anisotropic in the desired direction, i.e., to create an anisotropic drape material. The anisotropic drape material is configured to move, contract, or expand to a greater degree in a given direction or axis than in another direction or axis. This behavior is also discussed below in conjunction with fig. 9. As used herein, the term "coupled" includes coupling through separate objects and includes direct coupling. The term "coupled" also includes two or more components that are contiguous with each other by virtue of each of the components being formed from the same piece of material. Furthermore, the term "coupled" may include chemical (e.g., by chemical bonding), mechanical, thermal, or electrical coupling. Fluid coupling means that fluid is in communication between specified components or locations.

In the illustrative embodiment of fig. 1, the over-drape 62 may be sized to extend out of the shaped dressing bolster 32 to form a drape extension 64. The drape extension 64 has a first surface 66 and a second, tissue-facing surface 68. The over-drape 62 may be sealed against the patient's epidermis 14 (or against another layer, such as a cushion or another sealing member) using a sealing device 69 for providing a fluid seal. As used herein, reference to a seal on the patient's epidermis should be considered to include a seal against another layer, such as a membrane cushion, that may contact and seal with the patient's epidermis. The fluid seal allows reduced pressure to be maintained by the reduced-pressure subsystem 80. The sealing means 69 may take many forms, such as an adhesive 70; sealing tape or drape tape or strip; double-sided drape tape; pasting; a hydrocolloid; a hydrogel; or other sealing means. If a tape is used, the tape may be formed of the same material as the over-drape 62 with a pre-applied pressure sensitive adhesive. An adhesive 70 may be applied on the second surface 68 of the drape extension 64. The adhesive 70 provides a substantial fluid seal between the over-drape 62 and the patient's epidermis 14. The adhesive 70 may have a removable strip or releasable backing covering the adhesive 70 before the over-drape 62 is secured to the patient. The over-drape 62 may be formed as a unitary drape or by coupled sections or portions.

The reduced-pressure subsystem 80 includes a reduced-pressure source 82 or treatment unit. The reduced pressure source 82 may be a vacuum pump, wall suction, or other source. The reduced-pressure source 82 provides reduced pressure as part of the system 10. While the amount and nature of reduced pressure applied to the tissue site will generally vary depending on the application, the reduced pressure will generally be between-5 mm Hg to-500 mm Hg and more typically between-100 mm Hg to-300 mm Hg.

To maximize patient mobility and comfort, the reduced-pressure source 82 may be a battery-powered single-use reduced-pressure generator. Battery with a battery cellPowered single use reduced pressure generators facilitate application in an operating room and provide mobility and convenience to the patient during the rehabilitation phase. For many procedures, it is believed that the patient will be instructed to wear the reduced pressure system 10 for three to five days, and may be instructed to wear the reduced pressure system 10 for fifteen days or more. This treatment time may still be less than conventional treatments (e.g., conventional compression garments, which are often worn for up to six weeks). Thus, the battery life or power supply of such a reduced pressure source 82 may need to accommodate up to 15 days of operation. Other reduced pressure sources may be utilized, such as v.a.c. available from KCI of san antonio, texas.A therapy unit, or a wall-mounted inhalation unit. The reduced pressure source 82 may also be provided by a portable mechanical device (e.g., a piston in a tube) depending on how much leakage the fluid seal between the shaped dressing bolster 32 and the epidermis 14 is used.

In the illustrative embodiment of fig. 1, reduced-pressure source 82 is shown with a battery compartment 84 and a canister region 86, canister region 86 having a window 88 that allows visual indication of the level of fluid within canister 86. An interposed membrane filter, such as a hydrophobic or oleophobic filter, may be interspersed between the reduced-pressure delivery conduit or tube 90 and the reduced-pressure source 82.

The reduced pressure generated by the reduced-pressure source 82 is communicated through a reduced-pressure delivery conduit 90 to a reduced-pressure interface 92, which reduced-pressure interface 92 may be an elbow-shaped port 94. In an illustrative embodiment, elbow 94 is a TRAC available from KCI of san Antonio, TexasProcess port (technology port). The reduced-pressure interface 92 allows reduced pressure to be communicated through the sealing subsystem 60 and to be achieved within interior portions of the sealing subsystem 60. In this illustrative embodiment, the port 94 extends through the over-drape 62 and into the shaped dressing bolster 32.

In operation, reduced pressure system 10 may be applied to a patient after a surgical procedure in an operating room or elsewhere. The second surface 36 of the shaped dressing bolster 32, which may include a comfort layer (see, e.g., fig. 16), will be placed against the patient's epidermis 14 with the shaped dressing bolster 32 placed over the injured subcutaneous tissue site 20 and a portion placed over the incision 12. The dressing assembly 30 may be pre-sized or sized at the time for typical applications involved in the procedure performed by the care provider. The dressing assembly 30 may be sized, shaped, and configured to function in different tissue applications (e.g., abdominal, thoracic, thigh, extremity, etc.).

If the over-drape 62 is not already coupled (see other illustrative embodiments) to the shaped dressing bolster 32, the over-drape 62 will be placed over the first surface 34 of the shaped dressing bolster 32 with an additional portion extending beyond the perimeter edge 38 to form a drape extension 64. The drape extension 64 may then be taped down (see 172 in fig. 2) or adhered with an adhesive 70 (fig. 1) that forms a fluid seal between the over-drape 62 and the patient's epidermis 14. The fluid seal need only be sufficient to allow the reduced-pressure system 10 to maintain the reduced pressure in the desired location. The reduced-pressure interface 92 will then be applied if the reduced-pressure interface 92 has not been installed, and the reduced-pressure delivery conduit 90 will be coupled at one end. The other end of the reduced-pressure delivery conduit 90 would then be coupled to the reduced-pressure source 82. The reduced-pressure source 82 may then be activated and reduced pressure may be delivered to the shaped dressing bolster 32.

When the pressure at the shaped dressing bolster 32 is reduced, the shaped dressing bolster 32 compresses and laterally contracts and forms a semi-rigid substrate or less flexible substrate. The reduced pressure is transmitted through the shaped dressing bolster 32 such that the reduced pressure is applied to the patient's epidermis 14 at the point of the incision 12. At least during the early stages of the healing process and due to certain types of trauma, reduced pressure may be transmitted through the incision 12 and into the subcutaneous tissue 20, and the reduction in pressure may directly assist in closing the defect, such as the subcutaneous void 22, and generally provide stability to the area. The reduced pressure delivered to the shaped dressing bolster 32 also creates a compressive force 24 that again may provide stability, therapy, and may also close or help close the subcutaneous void 22. The compressive force 24 is preferably not at the epidermis 14. For example, the compressive force 24 may exert a force at the level of the subcutaneous tissue 20 or other subcutaneous body structure.

When the upper drape 62 and shaped dressing bolster 32 are laterally contracted under the influence of reduced pressure, and when a compressive force is applied to the epidermis 14, a net closing force 26 is generated, the net closing force 26 may help keep the incision 12 closed and may generally provide additional stability to the area. The effective tensile strength of the incision 12 may be increased. The closing force 26 may depend in part on the friction between the shaped dressing bolster 32 and the epidermis 14 to transmit the closing force to the epidermis 14, and may involve transmission of force from the drape extension 64 to the epidermis 14 via the adhesive 70 or by friction if adhesive tape (172 in fig. 2) is used. At the same time, the reduced pressure delivered to the shaped dressing bolster 32 and through the shaped dressing bolster 32 helps remove any exudates or other fluids from the incision 12. In one aspect, the reduced-pressure system 10 inhibits the formation of wrinkles in the epidermis 14. The system 10 may deliver an average amount of force to the epidermis 14, maintaining the epidermis 14 in a smooth or wrinkle-free configuration for healing.

The reduced-pressure system 10 may avoid skin irritation, such as blistering of the patient's epidermis 14 that may result from secondary shear forces, secondary strain, or other effects. To this end, the ends 33 of the shaped dressing bolster 32 may be shaped to provide an even distribution of radial compressive forces. The terminal end 33 is the outer shaped portion of the shaped dressing bolster 32 and the peripheral edge is typically the outermost portion of the shaped dressing bolster 32 or the outermost portion that engages the patient's skin. The tip 33 may take many different shapes to help evenly distribute the compressive force or otherwise avoid stress risers. Possible shapes for the tip 33 include the following: a chamfered (or angled, sloped, or tapered) surface as shown in fig. 1, an arcuate shape as shown in fig. 2, or other shape that distributes the force. Conversely, when a bolster with square edges is used, a "tent area" may be formed when an over-drape is applied over the bolster and into the patient's epidermis. The "tent area" can cause skin irritation unless other measures are taken. The shaped dressing bolster 32 avoids a "tent area". The shaped edges or ends of the dressing bolster allow compressive forces to be generated without a large "edge effect"; i.e. not to raise the shear or stress to a level that causes skin irritation (e.g. erythema or blisters). The shaped portion of the shaped dressing bolster 32 gradually distributes the force to avoid irritation. This manner of carefully applying force to the skin to avoid irritation is often referred to as "evenly distributing" the compressive force, but is not strictly used in a literal sense. As another precaution against skin irritation, an inner layer may be added between the shaped dressing bolster 32 and the patient's epidermis 14 (see, e.g., 857 in fig. 11) or placed elsewhere, as explained further below in connection with other illustrative embodiments.

It may be desirable to apply the reduced-pressure system 10 in an operating room and allow the reduced-pressure system 10 to remain on the patient until sufficient healing has occurred. In this regard, it may be desirable to form the over-drape 62, shaped dressing bolster 32, and any other layers from a see-through material to allow the care provider to obtain visual cues as to the healing of the incision 12 and damaged subcutaneous tissue 20 without having to remove the dressing assembly 30.

Referring now to FIG. 2, another illustrative embodiment of a system 110 for treating damaged or destroyed or abnormal subcutaneous tissue in a patient is shown. The system 110 is similar in most respects to the reduced-pressure system 10, and in this embodiment, the correlation of the components is generally represented by the numerical adjustment 100 and may not be mentioned further. In this particular illustrative embodiment, the system 110 is placed on intact epidermal tissue 115, i.e., without an incision in this case. However, there is damaged subcutaneous tissue 120 including subcutaneous space 122. The system 110 assists in the injured subcutaneous tissue 120, whether or not there is an incision.

While the shaped dressing bolster 32 of fig. 1 is shown as having a trapezoidal cross-section, the shaped dressing bolster 132 of fig. 2 has a cross-section that is formed with a portion having a radiused edge or having an arcuate cross-section. The arcuate cross-section of the shaped dressing bolster 132 is oval or elliptical. The shaped dressing bolster 132 may be shaped to have a double-sloped cross-section or other shape. As before, the shape of the shaped dressing bolster 132 facilitates "even distribution" of the radial compressive force to the extent that skin irritation is avoided during use of the system 110. The end 133 of the shaped dressing bolster 132 is shown as having an oval cross-section. In the illustrative embodiment of fig. 2, the sealing device 169 provides a fluid seal between the upper covering cloth 162 and the patient's epidermis 114, and in this case, the sealing device 169 is a sealing tape 172.

The resulting force will now be described further. The ambient pressure provides a vertical force 131 on the first surface 161 of the upper drape 162, and the contraction of the shaped dressing bolster 132 generates a compressive force 124 to provide a force directed toward the epidermis 114 and to the subcutaneous level (i.e., to the subcutaneous tissue 118). At the same time, a lateral force or a closing force can be generated. The closing force is transmitted to the epidermis through the shaped dressing bolster 132. Force 127 is the inward contractive force caused by the contraction and compression of the shaped dressing bolster 132. As the shaped dressing bolster 132 contracts and compresses, the closing force is transmitted through the shaped dressing bolster 132 to the epidermis 114. Meanwhile, for the present illustrative embodiment, when reduced pressure is applied, the over-drape 162 is pulled into the area proximate the end 133, as indicated by arrow 128. Because the drape extension 164 is secured to the epidermis 114, the horizontal component of the force 128 will pull the epidermis inward, as illustrated by the inward closing force 129.

Referring now primarily to fig. 3, a system 210 for treating tissue (e.g., damaged subcutaneous tissue 220) is shown on a curved body part 200 (e.g., a torso of a patient). Dressing assembly 230 includes a shaped dressing bolster 232. The sealing subsystem 260 includes an over-drape 262 and an attachment tool 270. A reduced-pressure source (not shown) provides reduced pressure to the reduced-pressure delivery conduit 290, the reduced-pressure delivery conduit 290 delivers the reduced pressure to a reduced-pressure interface 292, which, in turn, delivers the reduced pressure to the shaped dressing bolster 232. When shaped dressing bolster 232 is compressed under the influence of reduced pressure, a net radial compressive force 224 is generated that is transmitted to subcutaneous tissue 220. The over-drape 262 forms a "tent" area around the void 235. Under reduced pressure, the over-drape 262 is pulled into the void 235, and thus a force is applied that produces an inwardly contracting force 226. Alternatively, the ends of the shaped dressing bolster 232 may be shaped to avoid a tent area, or an over-drape may be attached to the ends of the shaped dressing bolster 232.

In the embodiment of fig. 3, the curvature of the shaped dressing bolster 232 also helps create the compressive force. The first surface 234 of the shaped dressing bolster 232 has a surface area that is greater than the surface area of the inward-facing second surface 236 of the shaped dressing bolster 232, and this difference in surface area also facilitates the generation of the net compressive force 224 under reduced pressure.

Referring now primarily to FIG. 4, an illustrative system 310 is shown. System 310 is substantially similar in most respects to system 210 of fig. 3, and similar components are represented by the reference numeral 100 of fig. 3 and may not be mentioned further. System 310 shows a ring-shaped dressing assembly 330, in this illustrative embodiment, the ring-shaped dressing assembly 330 extends completely around the circumference of the torso. The tangential forces are generated during the application of reduced pressure and are combined in the system 310 to generate a net radial compressive force 324. The compressive force 324 may be applied relatively higher than a plane or partial torso because no force is offloaded to the drape and epidermis.

Referring now primarily to fig. 5 and 6, another illustrative embodiment of a dressing assembly 430 is shown. The dressing assembly 430 has a shaped dressing bolster 432, the shaped dressing bolster 432 having a first surface 434 and an inwardly facing (skin-facing or patient-facing) second surface 436. In this illustrative embodiment, the shaped dressing bolster 432 has been formed with an angled tip 433, and in particular with a trapezoidal cross-section in two orthogonal planes, such as orthogonal planes 440 and 442. A cross-section along one such plane of the dressing assembly 430 is shown in fig. 6. The peripheral edge 438 of the shaped dressing bolster 432 is formed to have an angle a between a perpendicular (for the orientation shown) or normal reference line 444 and a surface extension line (in cross-section) 446. The angle a will typically be between 3 and 95 degrees, and more typically between 20 and 65 degrees, and more typically about 45 degrees.

The over-drape 462 is placed over the shaped dressing bolster 432. The over-drape 462 extends beyond the peripheral edge 438 to form drape extensions 464, each drape extension 464 having a first side 466 and an inwardly facing second surface 468. The over-drape 462 may be coupled using any of a number of tools or techniques (e.g., using adhesives and gluing), as mentioned above. In this illustrative embodiment, the over-drape 462 is coupled to the outer portion 439 of the peripheral edge 438 by an adhesive 450. The over-drape 462 may also be coupled to an outer surface 435 of the first surface 434 of the shaped dressing bolster 432. In this illustrative embodiment, the over-drape 462 can be coupled at least partially to substantially all of the outer surface of the shaped dressing bolster 432, unless the surface is facing the patient. When the upper covering cloth 462 is coupled to substantially all of the outer surface of the shaped dressing bolster 432, except for the inward facing surface, the peripheral edge 438 may be shaped to have a right angle and still avoid skin irritation, as no "tent area" may be formed. Otherwise, the edge 438 is shaped without a right angle. Optionally, layers may be added to help minimize skin irritation.

As shown in fig. 5, a reduced-pressure delivery conduit 490 as part of the reduced-pressure subsystem may be used to provide reduced pressure to a delivery reduced-pressure interface 492, the reduced-pressure interface 492 delivering reduced pressure into the shaped dressing bolster 432. The reduced-pressure interface 492 may be a port 494 or direct application into the bolster 432 or other tool.

Referring now primarily to fig. 7, another illustrative embodiment of a dressing assembly 530 is shown. The dressing assembly 530 has a shaped dressing bolster 532 formed with a rectangular cross-section. In this case, the over-drape 562 is coupled to the outer surface 539 of the peripheral edge 538 and to the first surface 534 of the shaped dressing bolster 532, such as by gluing using an adhesive 550. The adhesive 550 may facilitate a more even application of the radial compressive force to the patient even if the shaped dressing bolster 532 is shaped to have a right angle. Although the coupling is shown entirely along the outer portion 539 of the peripheral edge 538 and on the outer surface 535 of the first surface 534, the portion that is coupled may be partial or implemented with a tacking pin.

Referring now primarily to fig. 8, another illustrative embodiment of a dressing assembly 630 is shown. The dressing assembly 630 has a shaped dressing bolster 632 formed with an arcuate cross-section, in this case an elliptical or oval cross-section. Thus, the peripheral edge 638 has a rounded or curved shape. The over-drape 662 may be coupled to the outer surface 639 of the peripheral edge 638 and to the outer surface 635 of the first surface 634 of the shaped dressing bolster 632 by an adhesive 650. The elliptical cross-section may exist in two different orthogonal planes.

Referring now primarily to fig. 9, an illustrative embodiment of a medical bolster material 635 is shown with respect to a first axis 674, a second axis 676, and a third axis 678. The medical bolster material 635 may be used in any of the shaped dressing bolsters mentioned above. While in many applications the medical bolster material 635 may be isotropic, in other applications it may be desirable to have an anisotropic material like the medical bolster material 635.

Anisotropy is generally a directionally dependent property, as opposed to isotropy, which means homogeneity in all directions. For example, if it is desired to generate a force that is stronger than the force applied to the exterior of the patient against gravity, an anisotropic material may be used such that when a net tangential force is generated along the first axis 674, a larger movement is generated along the vertical axis a, which in this case is the third axis 678 for the direction shown. In other cases, it may be desirable to have different performance also in the direction of the second axis 676. The anisotropic material may be formed by adding filaments in a first direction. Anisotropic materials can also be formed by bonding (thermo-compression) the materials to produce lines with different densities. The anisotropic material may also be formed by using an adhesive that imparts strength in a given direction.

Referring now primarily to FIG. 10, a portion of an illustrative embodiment of a system 710 for treating tissue, such as damaged subcutaneous tissue, is shown. The system 710 includes a shaped dressing bolster 735, a sealing subsystem 760, and a reduced-pressure subsystem 780, only a portion of the reduced-pressure subsystem 780 being shown. The shaped dressing bolster 735 may be part of a dressing assembly 730 that includes a breathable drying layer 741 having a first surface 743 and an inward-facing second surface 745. The dressing assembly 730 may also include an air impermeable layer 747 having a first surface 749 and an inwardly facing second surface 751. The sealing subsystem 760 includes an attachment tool 770 and an over-drape 762 similar to the embodiments discussed above.

Many materials are possible for each layer 741, 732, 747. The breathable drying layer 741 may be formed, for example, from a hydrophilic nonwoven material that allows fluid to flow into the shaped dressing bolster 735. The through-air-drying layer 741 may be a comfort layer that helps avoid skin irritation or otherwise enhance comfort. The shaped dressing bolster 735 may be formed of a relatively thin absorbent structure or material that may store a relatively large amount of fluid. For example, the shaped dressing bolster 735 may be formed from a superabsorbent polymer (SAP) of the type often referred to as a "hydrogel," superabsorbent, "or" hydrocolloid. The shaped dressing bolster 735 may also be formed from any of the manifold materials mentioned above. The air impermeable layer 747 may be formed of many different materials, such as a polyethylene film that will keep fluid from leaking. Additional substrates may be added. The various layers 741, 732, 747 may be sealed or bonded with an adhesive (e.g., a hot melt adhesive), or hot glued, or coupled using any technique or means.

In operation, as fluid is added to the shaped dressing bolster 735, the shaped dressing bolster 735 becomes stiffer (less flexible) and this results in an increased radial compressive force, such as radial force 24 in fig. 1, under reduced pressure. The fluid may be present as exudate or other fluid from the wound, or may be a supplemented fluid, such as saline added intentionally through a second port, second cavity, or by injection through the dressing assembly in an injection port. In this sense, the shaped dressing bolster 735 may be considered a liquid-controlled bolster because additional liquid may be added to make the shaped dressing bolster 735 more rigid (less flexible) and result in greater force.

Still referring to fig. 10, an alternative illustrative embodiment of the dressing assembly 730 is shown by describing other possible elements. In this illustrative embodiment, the bolster includes two members: a first bolster layer 741 formed of hydrophilic foam and a second bolster layer 732 formed of hydrophobic foam. An over-drape 762 is then placed over the first surface (the top surface for the orientation shown) of the second bolster layer 732. Other layers made of various materials may also be added.

Referring now primarily to fig. 11, an illustrative embodiment of a dressing assembly 830 for use in a system for treating tissue, such as damaged subcutaneous tissue, is shown. The dressing assembly 830 includes a shaped dressing bolster 832 and an over-drape 862, which are generally similar to those shown in other embodiments herein. The sealing subsystem 830 includes an over-drape 862, the over-drape 862 extending out of the shaped dressing bolster 832 to form a drape extension 864, the drape extension 864 having a first surface 866 and an inwardly facing second side 868. A sealing arrangement 869 may be used to provide a seal between the drape extension 864 and the patient's epidermis 814. In this illustrative embodiment, the sealing device 869 is an adhesive 867, the adhesive 867 being placed on the patient facing surface. The adhesive 867 may be initially covered by a cover or releasable backing that may be peeled back before the dressing assembly 830 is applied to the patient's epidermis 814. The dressing assembly 830 shows the addition of an inner layer 853 having a first surface 855 and an inwardly facing second surface 857. The inner layer 853 is formed with a treatment area hole 859.

The inner layer 853 may help reduce or eliminate the potential for forming the dressing bolster 832And the epidermis 814 of the patient. The inner layer 853 may be an acrylic drape material (e.g., Avery)Acrylic drape), Scapa silicone drape, or other suitable material. The inner layer 853 is placed around the perimeter of the second surface 836 of the shaped dressing bolster 832 where the shaped dressing bolster 832 would otherwise engage the patient's skin. The inner layer 853 and over-drape 862 wrap the shaped dressing bolster 832 except for the treatment area aperture 859. Adhesive may be applied on the second surface 857 of the inner layer 853 to promote a splinting effect on the area where the interaction of the shaped dressing bolster 832 with the epidermis is over and the over-drape 862 begins. This arrangement can help prevent blistering caused by high concentrations of shear stress and strain when reduced pressure is applied, as the adhesive is believed to help prevent the skin from rolling or pilling and forming pressure points or pressure rises.

Referring now primarily to fig. 12, an illustrative embodiment of a dressing assembly 930 is shown in an exploded view. The dressing assembly 930 has a shaped dressing bolster 932, an inner layer 953, and an over-drape 962. The inner layer 953 has a first surface 955, an inwardly facing second surface 957, and is formed with a treated area hole 959. The shaped dressing bolster 932 is an example of a shaped dressing bolster 932 having a sloped surface (peripheral edge 938 is formed at an angle to a vertical axis) and thus in this case forms a trapezoidal cross-section in at least two orthogonal planes. The shaped dressing bolster 932 has a first surface 934 and an inwardly facing second surface 936. The over-drape 962 has a first surface 966 and an inwardly facing second surface 968.

The inner layer 953 may be used in a number of ways to address the possibility of skin irritation. In an illustrative embodiment, the second surface 936 of the shaped dressing bolster 932 is coupled to the first surface 955 of the inner layer 953. In another illustrative embodiment, no adhesive or other connecting bonding means is used between the shaped dressing bolster 932 and the inner layer 953 to allow relative movement between the shaped dressing bolster 932 and the inner layer 953. Similarly, a second surface 968 of the over-drape 962 may be coupled to the first surface 934 of the shaped dressing bolster 932. In an alternative embodiment, there may be no attachment means between surfaces 934 and 968.

Yet another illustrative embodiment involves coupling all of the exterior surface of the shaped dressing bolster 932 to the over-drape 962, except for a second, inward-facing surface 936 of the shaped dressing bolster 932. An adhesive or other attachment means may be used to couple the first surface 955 of the inner layer 953 to the second surface 936 of the shaped dressing bolster 932. No adhesive or attachment means is applied on the second surface 957 and thus skin irritation may be reduced as the relatively low friction surface of the inner layer 953 is allowed to slide relative to the skin. Optionally, an adhesive or other attachment means may be applied to the second surface 957 of the inner layer 953 to hold the inner layer 953 to the epidermis, but not between the shaped dressing bolster 932 and the inner layer 953, so as to allow for lower friction movement between the shaped dressing bolster 932 and the inner layer 953.

In yet another alternative form of this illustrative embodiment, an adhesive or other bonding means may be applied between the second surface 936 of the shaped dressing bolster 932 and the first surface 955 of the inner layer 953 and between the second surface 957 of the inner layer 953 and the patient's epidermis. With this alternative form, the splint effect is achieved in the area where the interaction of the shaped dressing bolster 932 with the epidermis is over and the interaction of the inner layer 953 with the epidermis begins. This arrangement helps prevent blistering caused by high concentrations of shear stress and strain placed at this location when reduced pressure is applied. The adhesive or joining means is believed to prevent the skin from rolling or pilling and forming pressure points or pressure elevations. The inner layer 953 configuration can be used in any of the illustrative embodiments shown, as well as others.

Referring now primarily to fig. 13 and 14, an illustrative embodiment of a dressing assembly 1030 is shown. The dressing assembly 1030 has a shaped dressing bolster 1032, the shaped dressing bolster 1032 having a first surface 1034 and a second surface 1036. In this illustrative embodiment, the ends 1033 of the shaped dressing bolster 1032 are angled. An inner layer 1053 having a first surface 1055 and an inwardly facing second surface 1057 is provided, but in this case, the second surface 1057 is positioned adjacent the peripheral edge 1038 of the shaped dressing bolster 1032. The inner layer 1053 is formed with a central aperture 1059. The inner layer 1053 and a portion of the shaped dressing bolster 1032 are covered by an over-drape 1062. An adhesive or other attachment means may be used between the first surface 1055 of the inner layer 1053 and the second surface 1063 of the over-drape 1061 or between the second surface 1057 of the over-drape 1053 and the first surface 1034 of the shaped dressing bolster 1032.

Referring now primarily to fig. 15-16, a portion of a system 1110 for treating linear wounds, regional wounds, other wounds, or grafts is shown. This portion of the system 1110 is shown in a pre-deployment state in fig. 15.

The system 1110 includes an dressing assembly 1130, the dressing assembly 1130 including a shaped dressing bolster 1132. The shaped dressing bolster 1132 has a first side 1134 and a second, inward-facing side 1136. The shaped dressing bolster 1132 may be formed of any medical bolster material as discussed above using other embodiments. A comfort layer 1170 having a first side 1172 and an inward-facing second side 1174 can be coupled to the second side 1136 of the shaped dressing bolster 1132, for example, by a thermal adhesive 1176 or any other technique.

The comfort layer 1170 may be any material that helps prevent skin irritation and discomfort while allowing fluid transport through the comfort layer 1170. As a non-limiting example, a woven elastomeric material or a polyester knit fabric substrate may be used. As another non-limiting example, InterDry (TM) fabric material from Milliken Chemical of St.Patanburg, south Carolina may be used. The comfort layer 1170 may be an antimicrobial substance, such as silver. The comfort layer may be manufactured like the through-air-drying layer 741 of fig. 10.

In one embodiment, the shaped dressing bolster 1132 may include a plurality of flexibility notches 1178. The flexibility notch 1178 can be a transverse notch or transverse cut in the shaped dressing bolster 1132 as shown, and additionally or alternatively, can be one or more longitudinal notches or longitudinal cuts or other cuts. The cuts may be made using a saw (or notched blade), a hot knife, or other tool. Flexibility notch 1178 enhances the flexibility of shaped dressing bolster 1132. The enhanced flexibility may be particularly useful when the dressing assembly 1130 is applied over a joint or other moving area of a patient. For example, if the shaped dressing bolster 1132 is used on a knee, the shaped dressing bolster 1132 may need to bend or extend up to 100% or more, and the flexibility notch 1178 or ridge helps provide the desired flexibility. Additionally, a plurality of pleats 1173 may be added to facilitate movement, as further described below.

In one illustrative embodiment, the shaped dressing bolster 1132 is manufactured as follows. Cutting a piece of GranuFoam having a height of 19mmMaterial (e.g., a block of 1.21 meters by 1.8 meters by 0.5 meters) and a saw is used to form the lateral slot or lateral flex notch 1178. A drying layer, which may be a comfort layer 1170, is then laminated to the second or bottom surface. The foam pieces are then cut using die cutting to form individual shaped dressing pillows 1132.

The sealing subsystem 1160 provides a fluid seal over the dressing assembly 1130 and at least a portion of the patient's epidermis. The sealing subsystem 1160 includes an over-drape 1162, the over-drape 1162 may be formed to have a first over-drape portion 1163 and a second over-drape portion 1165. The first over-drape portion 1163 extends over the first side 1134 of the shaped dressing bolster 1132, and further extends to form a drape flange or drape extension 1164 having a first side 1166 and an inward-facing second side (not expressly shown). An aperture 1181 is formed on a portion of the first over-drape 1163. The aperture 1181 is used to allow fluid communication with a reduced-pressure interface (e.g., the reduced-pressure interface 92 in fig. 1).

A second, inward-facing side of the drape extension 1164 is placed on the first side 1167 of the second over-drape portion 1165 and coupled, for example, by an adhesive, cohesive 1169, other coupling techniques or tools such as those mentioned above. The first drape portion 1163 may include a plurality of folds 1173 or corrugations. The folds 1173 allow the first drape portion 1163 to expand, if necessary. For example, if the dressing assembly 1130 is used on a joint, the drape portion 1163 is extended with the folds 1173 when the joint is flexed. Additional drape material may be released from pleats 1173 to facilitate movement. The second, inward-facing side of the second drape portion 1165 may have adhesive on one portion and may have a treatment area aperture (see, by way of analogy, treatment area aperture 1271 in fig. 17). Pleats 1173 may also be formed as ridges that appear in cross-section as accordion-like ridges that flatten when stretched and thereby provide additional material.

One or more release members 1182 may be releasably coupled to the first side 1167 of the second drape portion 1165. Four release members 1182 are shown in the illustrative embodiment of fig. 15. The release member 1182 provides rigidity and assistance during deployment of the dressing assembly 1130. The release member 1182 is typically a cast-coated paper or film that is retained on the first side 1167 of the second drape portion 1165.

Referring now primarily to fig. 17, an exploded perspective view of a portion of a system 1210 for treating tissue, such as subcutaneous tissue, linear wounds, regional wounds, other wounds, or grafts, is shown. The portion of the system 1210 represented in fig. 17 is shown in a pre-deployed state and in an exploded view. System 1210 is substantially similar in most respects to system 1110 of fig. 15-16, and to represent corresponding parts, reference numerals have been adjusted by 100 and may not be mentioned further. The system 1210 includes a dressing assembly 1230, the dressing assembly 1230 including a shaped dressing bolster 1232. The shaped dressing bolster 1232 is the same as the shaped dressing bolster 1132, but the flexibility notch 1278 is both transverse and longitudinal.

The first side 1234 of the shaped dressing bolster 1232 is covered by an over-drape 1262, which over-drape 1262 may include a first drape portion 1263 and a second drape portion 1265. The first drape portion 1263 includes folds 1273 and an aperture 1281. The second drape portion 1265 is formed with a treatment area aperture 1271, the treatment area aperture 1271 providing an opening for at least a portion of the shaped dressing bolster 1232 (or comfort layer) to rest directly against the patient's epidermis or treatment site. The second drape portion 1265 has a first side 1267 and has an adhesive 1283 coated on a portion of the first side 1267. The adhesive 1283 primarily serves to hold the shaped dressing bolster 1232 against the second drape portion 1265 during assembly during manufacture, and also serves to help hold the shaped dressing bolster 1232 during use. Prior to applying the shaped dressing bolster 1232 against the adhesive 1283, the adhesive 1283 is covered by the central releasable member 1284. On the outside of the adhesive 1283 on the first side 1267 is a releasable member 1282 that provides stiffness to the overlying cloth 1262 during deployment.

A second, inward-facing side (not explicitly shown, but the side opposite the first side 1267) of the second drape portion 1265 may be covered by an adhesive. In the pre-deployed state, the adhesive is covered by the bottom release member 1286 and the side release members 1287.

Once assembled, the portions of system 1210 are similar to the portions of system 1120 of fig. 15. Usage and design may vary, but in one illustrative embodiment, portions of system 1210 may be deployed, as will be described. The bottom release liner 1286 is removed and the exposed adhesive on the second, inward-facing side of the second drape portion 1265 is placed against a portion of the patient's epidermis starting at one end and may be placed over a linear wound. After the second drape portion 1265 is applied smoothly, the side release member 1287 is removed. The release member on the first side 1267 of the upper covering cloth 1262 is removed. The reduced-pressure interface is coupled to an aperture 1282 in the first over-drape portion 1263. Central release member 1284 has been removed during manufacture.

The components and their assembly have been shown with respect to making the systems and components described above. When applying and coupling the over-drape to the first surface of the shaped dressing bolster, it may be desirable to remove any wrinkles with compression that may otherwise develop or remain. The medical bolster material of the shaped dressing assembly may be cut using die cutting or by hand using a router.

According to another illustrative embodiment, a reduced-pressure system for treating a tissue site includes a directed-force member having non-orthogonal edges, such as curved edges, beveled or angled edges, or edges bonded to a portion of a drape, for evenly distributing a force when placed under reduced pressure. The force directing member may be formed as a foam member having a plurality of channels for transporting fluid. The reduced-pressure system also includes a drape for providing a fluid seal over at least a portion of the force-directing member and the patient's epidermis. The system may also have a reduced-pressure conduit for fluidly coupling the reduced-pressure source and the directed force member. In one illustrative embodiment, the force directing member is a foam member having tapered edges. When reduced pressure is delivered to the interior portion by the reduced pressure source through the drape, the reduced pressure causes the force-directed member to apply a force. The force may include a vertical force against the patient's epidermis or other tissue that may penetrate to greater than 1 millimeter, greater than 2 millimeters, greater than 3 millimeters, greater than 4 millimeters, greater than 5 millimeters, greater than 7 millimeters, and deeper. Vertical forces may help to bring the dead space and the gap closer together. The force may be or include a closing force.

According to another illustrative embodiment, a reduced-pressure force-producing dressing assembly includes a directional force member having a beveled edge for evenly distributing force when placed under reduced pressure. The force directing member has a top side and a bottom side. The force directing member is formed from a medical bolster material having a plurality of channels. The flow channels may be interconnected, such as foam. The dressing assembly may further include a drape for providing a fluid seal over at least a portion of the force-directing member and the patient's epidermis. The directional force member may have an angled tip. Alternatively, the force directing member may have an arcuate end. The dressing assembly may also have a comfort layer coupled to the bottom side of the force-directing member. The comfort layer may be a breathable dry layer coupled to the bottom side directed towards the force member, or any other material that helps to avoid maceration of the skin or any kind of skin irritation.

According to another illustrative embodiment, a method of treating damaged subcutaneous tissue on a patient includes positioning a shaped dressing bolster over the damaged subcutaneous tissue. The shaped dressing bolster has an angled end and is formed from a medical bolster material. The method further includes draping a cover over a portion of the patient's epidermis and the shaped dressing bolster to provide a fluid seal, and providing a reduced pressure source. The method also includes coupling a reduced-pressure interface to the drape and fluidly coupling a reduced-pressure delivery conduit to a reduced-pressure source and the reduced-pressure interface. The method also involves activating the reduced-pressure source to provide reduced pressure to the shaped dressing bolster to generate the compressive force and the closing force. The compressive force may be achieved at the subcutaneous tissue or other subcutaneous body structure.

Although the present invention and its advantages have been disclosed in the context of certain illustrative non-limiting embodiments, it should be understood that various changes, substitutions, permutations and alterations can be made herein without departing from the scope of the invention as defined by the appended claims. It will be appreciated that features described in connection with any one embodiment may also be applicable to any other embodiment.

Claims

1. A dressing assembly for a reduced pressure treatment system, the dressing assembly comprising:

a shaped dressing bolster having a first surface, an inwardly facing second surface;

a beveled tip forming a portion of the shaped dressing bolster;

wherein the shaped dressing bolster is formed of a medical bolster material, the shaped dressing bolster for placement on a patient's epidermis;

wherein the medical bolster material has greater than 20kg/m³Is close toDegree; and

wherein the shaped dressing bolster has the feature of evenly distributing directional forces when under reduced pressure.

2. The dressing assembly of claim 1 wherein the angled surface of the tip is at an angle alpha (a) from a normal reference, and wherein the angle alpha (a) is greater than five degrees (a > 5 degrees).

3. The dressing assembly of claim 1 wherein the angled surface of the tip is at an angle alpha (a) from a normal reference, and wherein the angle alpha (a) is greater than ten degrees (a > 10 degrees).

4. The dressing assembly of claim 1 wherein the angled surface of the tip is at an angle alpha (a) from a normal reference, and wherein the angle alpha (a) is in a range between 10 degrees and 70 degrees (70 ° > a > 10 °).

5. The dressing assembly of claim 1 wherein the angled surface of the tip is at an angle alpha (a) from a normal reference, and wherein the angle alpha (a) is in a range between 25 degrees and 65 degrees (65 ° > a > 25 °).

6. The dressing assembly of claim 1 further comprising an over-drape disposed on the first surface of the shaped dressing bolster.

7. The dressing assembly of claim 1 further comprising:

an over-drape disposed on the first surface of the shaped dressing bolster, an

A drape sealing device coupled to the over-drape for sealing the over-drape to the patient's epidermis.

8. The dressing assembly of claim 1 further comprising:

an over-drape disposed on the first surface of the shaped dressing bolster; and

wherein an over-drape material is coupled to the first surface of the shaped dressing bolster.

9. The dressing assembly of claim 1 further comprising:

an over-drape disposed on the first surface of the shaped dressing bolster, an

Wherein the over-drape comprises an anisotropic material.

10. The dressing assembly of claim 1, wherein the shaped dressing bolster further comprises a plurality of flexible notches formed on the first surface of the dressing bolster.

11. The dressing assembly of claim 1 further comprising an over-drape disposed on the first surface of the shaped dressing bolster; and wherein the shaped dressing bolster further comprises a plurality of flexible notches formed on the first surface of the dressing bolster.

12. The dressing assembly of claim 1 wherein the shaped tip comprises a member having a trapezoidal cross-section in two orthogonal planes.

13. The dressing assembly of claim 1 wherein the shaped tip comprises a member having an arcuate cross-section in two orthogonal planes.

14. The dressing assembly of claim 1 wherein the shaped tip comprises a member having an elliptical cross-section in two orthogonal planes.

15. The dressing assembly of claim 1 wherein the dressing assembly is,

wherein the shaped tip comprises a member having an arcuate cross-section in two orthogonal planes;

further comprising an over-drape disposed on the first surface of the shaped dressing bolster; and

wherein the over-drape is at least partially coupled to all exterior surfaces of the shaped dressing bolster except for the inward-facing second surface.

16. The dressing assembly of claim 1 wherein the dressing assembly is,

wherein the shaped tip comprises a member having a trapezoidal cross-section in two orthogonal planes;

wherein the over-drape is at least partially coupled to an exterior surface of the shaped dressing bolster.

17. The dressing assembly of claim 1 wherein the medical bolster material comprises an isotropic material.

18. The dressing assembly of claim 1 wherein the medical bolster material comprises an anisotropic material.

19. The dressing assembly of claim 1 further comprising a comfort layer coupled to the second, inward-facing surface of the shaped dressing bolster.

20. The dressing assembly of claim 1, further comprising an over-drape disposed on the first surface of the shaped dressing bolster, and wherein at least a portion of the first surface of the shaped dressing bolster is coupled to a portion of the over-drape.

21. The dressing assembly of claim 1 wherein the shaped dressing bolster comprises:

a first bolster layer formed of a hydrophilic foam and having a first surface and an inwardly facing second surface;

a second bolster layer formed of a hydrophobic foam and having a first surface and an inwardly facing second surface; and

wherein the first surface of the first bolster layer and the second surface of the second bolster layer are adjacently disposed.

22. The dressing assembly of claim 1 wherein the shaped dressing bolster comprises:

a first bolster layer formed of a hydrophilic foam and having a first surface and an inwardly facing second surface, the hydrophilic inwardly facing second surface for placement against the patient's epidermis;

wherein the first surface of the first bolster layer and the inward-facing second surface of the second bolster layer are adjacently disposed.

23. The dressing assembly of claim 1 wherein the shaped dressing bolster comprises a pillow having a height of greater than 25.6kg/m³A reticulated foam of density.

24. The dressing assembly of claim 1 wherein the shaped dressing bolster comprises a pillow having a height of greater than 32.0kg/m³A reticulated foam of density.

25. The dressing assembly of claim 1 wherein the shaped dressing bolster comprises a pillow having a height of greater than 80.0kg/m³A reticulated foam of density.

26. The dressing assembly of claim 1 wherein the shaped dressing bolster comprises a reticulated foam having a density less than a density of epidermal tissue.

27. The dressing assembly of claim 1 further comprising an inner layer having a first surface and an inwardly facing second surface, and wherein the first surface of the inner layer is at least partially coupled to a portion of the second surface of the shaped dressing bolster.

28. The dressing assembly of claim 1 further comprising:

covering a cloth;

a plurality of flexible notches formed on the first surface of the dressing bolster; and

wherein the inclined surface of the tip is at an angle alpha (a) to the normal reference, and wherein the angle alpha (a) is in a range between 25 degrees and 65 degrees (65 ° > a > 25 °).

29. The dressing assembly of claim 1 further comprising:

covering a cloth;

a plurality of flexible notches formed on the first surface of the dressing bolster;

an inner layer having a first surface and an inwardly facing second surface, and wherein the first surface of the inner layer is at least partially coupled to a portion of the second surface of the shaped dressing bolster; and

30. A dressing assembly for a reduced pressure treatment system, the dressing assembly comprising:

a shaped dressing bolster having a beveled end and having a first surface and an inwardly facing second surface;

an over-drape disposed on the first surface of the shaped dressing bolster and coupled to at least a portion of the first surface of the shaped dressing bolster, and wherein the over-drape extends out of the shaped dressing bolster to form a drape extension having a first side and a second, inward-facing side; and

an adhesive perimeter bar coupled to the second side of the drape extension and operable to provide a seal between a patient and the over-drape.

31. The dressing assembly of claim 30 wherein the shaped dressing bolster comprises a medical bolster material, and wherein the medical bolster material is an isotropic material.

32. The dressing assembly of claim 30 wherein the shaped dressing bolster comprises a medical bolster material, and wherein the medical bolster material is an anisotropic material.

33. The dressing assembly of claim 30 wherein the shaped dressing bolster comprises a medical bolster material shaped to have a trapezoidal cross-section in two orthogonal planes.

34. The dressing assembly of claim 30 wherein the shaped dressing bolster comprises a medical bolster material shaped to have a tip with a cross section that forms an arcuate portion in two orthogonal planes.

35. The dressing assembly of claim 30 wherein the shaped dressing bolster comprises a medical bolster material shaped to have an elliptical cross-section in two orthogonal planes.

36. A method of manufacturing a shaped dressing bolster for a reduced pressure treatment system, the method comprising the steps of:

providing a medical bolster material;

forming a shaped dressing bolster having a first surface and an inwardly facing second surface, wherein the shaped dressing bolster is formed from the medical bolster material;

wherein the shaped dressing bolster is operable to distribute reduced pressure and evenly distribute radial compressive forces; and

wherein the step of forming a shaped dressing bolster includes forming the shaped dressing bolster with a beveled tip.

37. The method of manufacturing a shaped dressing bolster as claimed in claim 36, wherein the shaped dressing bolster has a beveled tip with an angle greater than 5 degrees.

38. The method of manufacturing a shaped dressing bolster of claim 36, further comprising coupling a comfort layer to the second, inward-facing surface of the shaped dressing bolster.

39. The method of manufacturing a shaped dressing bolster as claimed in claim 36, further comprising the steps of: providing an over-drape, and coupling a second surface of the over-drape to the first surface of the shaped dressing bolster.

40. The method of manufacturing a shaped dressing bolster as claimed in claim 36, wherein the step of forming a shaped dressing bolster includes the steps of: the shaped tip is formed such that the tip forms a trapezoidal member having a trapezoidal cross-section in two orthogonal planes.

41. The method of manufacturing a shaped dressing bolster as claimed in claim 36, wherein the step of forming a shaped dressing bolster includes the steps of: the shaped tip is formed such that the tip forms a cross-section having arcuate portions in two orthogonal planes.

42. The method of manufacturing a shaped dressing bolster as claimed in claim 36, wherein the step of forming a shaped dressing bolster includes:

providing a catalyst having a molecular weight of greater than 20kg/m³A block of reticulated foam of density of (a);

cutting the reticulated foam to a desired height;

laminating a comfort layer to the reticulated foam; and

cutting the reticulated foam with a die to form a shaped dressing bolster.

43. A reduced-pressure, force-generating dressing assembly, the dressing assembly comprising:

a directional force member having a sloped edge for evenly distributing a directional force when placed under reduced pressure, the directional force member having a top side and a bottom side;

wherein the force directing member is formed from a medical bolster material having a plurality of channels; and

a drape to provide a fluid seal over at least a portion of the force-directing member and the patient's epidermis.

44. The dressing assembly of claim 43 wherein the plurality of channels are interconnected.

45. The dressing assembly of claim 43 wherein the force-directing member has an angled tip.

46. The dressing assembly of claim 43 wherein the force directing member has an arcuate end.

47. The dressing assembly of claim 43 further comprising a comfort layer coupled to the bottom side of the force directing member.

48. The dressing assembly of claim 43 further comprising a breathable desiccant layer coupled to the bottom side of the force-directing member.

49. A method for treating damaged subcutaneous tissue on a patient, the method comprising:

positioning a dressing assembly over the damaged subcutaneous tissue, wherein the dressing assembly has a shaped dressing bolster having a beveled tip and formed of a medical bolster material;

placing a drape over the dressing assembly and a portion of the patient's epidermis to provide a fluid seal;

setting a reduced-pressure source;

coupling a reduced-pressure interface to the over-drape;

fluidly coupling a reduced-pressure delivery conduit to the reduced-pressure source and the reduced-pressure interface;

activating the reduced-pressure source to provide a reduced pressure to the dressing assembly to generate a compressive force and a closing force.

50. The method of claim 49, wherein the shaped dressing bolster comprises a pillow having a thickness of greater than 25.6kg/m³A reticulated foam of density.

51. The method of claim 49, wherein the shaped dressing bolster comprises a pillow having a thickness greater than 32.0kg/m³A reticulated foam of density.

52. The method of claim 49, wherein the shaped dressing bolster comprises a pillow having a thickness greater than 80.0kg/m³A reticulated foam of density.