Detailed description of illustrative embodiments
In the following detailed description of illustrative embodiments, reference is made to the accompanying drawings, which form a part hereof. 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. To avoid detail not necessary to enable those skilled in the art to practice the embodiments described herein, the description omits certain information known to those skilled in the art. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the illustrative embodiments is defined only by the appended claims.
Referring to fig. 1, an illustrative embodiment of a reduced pressure treatment system 100 for treating a wound 102 at a tissue site 104 is depicted, which is centrally disposed in a wound bed (wind bed). The system 100 may include a manifold member 108 or simple manifold; an over-drape 110; and a reduced-pressure subsystem 112. The system 100 includes a gasket 128.
In one illustrative embodiment, the manifold member 108 is made of a porous, permeable foam-like material, and more specifically, a reticulated, open-cell polyurethane (open-cell polyurethane) or polyethylene foam that allows good permeability of wound fluids under reduced pressure. One such foam material that has been used is a polyurethane foam materialVACGranufoam dressing available from Kinetic Concepts of San Antonio, Texas (Kinetic Concepts, Inc. (KCI) of San Antonio, Texas) ((R))Addressing). Any material or combination of materials may be used as the manifold material, so long as the manifold material is operable to distribute reduced pressure. The term "manifold" as used herein generally refers to a substance or structure provided to assist in applying reduced pressure to, delivering fluids to, or removing fluids from a tissue site. The manifold generally includes a plurality of flow channels or paths that are interconnected to improve distribution of fluids provided to or removed from the tissue region surrounding the manifold. Examples of manifolds may include without limitation devices having structural elements arranged to form flow channels, porous foams such as open-cell foam (open-cell foam), porous tissue collection devices, and liquids, gels, and foams that include or cure to include flow channels. The manifold material may also be a combination or lamination of materials; for example, a first manifold layer of hydrophilic foam may be disposed adjacent to a second manifold layer of hydrophobic foam to form the manifold member 108.
In the range of about 400 to 600 micronsThe mesh of pores of the material helps to perform the manifold function, but other materials may be used as well. Anda material with a higher or lower density (smaller pore size) than a material may be desirable in some situations. The manifold member 108 may also be a reticulated foam that is subsequently bonded to about 1/3 thickness of its original thickness. Among the many possible materials, the following may be used:material or Foamex technology foam (www.foamex.com). In some instances, it may be desirable to add silver ions to the foam or other substances, such as antimicrobial agents, to the manifold member during the micro-soldering process. The manifold member 108 may be a bioabsorbable material or an anisotropic material.
An over drape 118 covers the manifold member 108 and extends past the peripheral edge 114 of the manifold member 108 to form a drape extension 116. The drape extension 116 has a first side 118 and a patient-facing second side 120. The drape extension 116 may be sealed against a seal 128 by a sealing device 124, such as an adhesive 126. The sealing device 124 may take a variety of forms, such as an adhesive sealing tape or drape tape or strip; covering cloth adhesive tapes on two sides; an adhesive 126; a paste; a hydrocolloid; a hydrogel; or other sealing means. If tape is used, it may be formed of the same material as the over-drape 110 with a pre-applied, pressure-sensitive adhesive. A pressure sensitive adhesive 126 may be applied on the second, patient-facing side 120 of the drape extension 116. The adhesive 126 provides a substantially pneumatic seal between the over-drape 110 and the gasket 128. The removable strip covering the adhesive 126 may be removed before the over-drape 110 is secured to the patient.
The over drape 110 may be an elastomeric material having apertures with a size less than about 20 microns, although other materials and sizes may be used. "elastic" refers to having the properties of an elastomer, and generally refers to a polymeric material having rubber-like properties. More specifically, most elastomers have an elongation greater than 100% and a significant amount of rebound. Rebound 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 (styrene butadiene rubber), chloroprene rubber (chloroprene rubber), polybutadiene rubber (polybutadiene), nitrile butadiene rubber (nitrile rubber), butyl rubber (butyl rubber), ethylene propylene rubber (ethylene propylene rubber)ubber), ethylene propylene diene monomer (ethylene propylene diene monomer), chlorosulfonated polyethylene (chlorosulfonated polyethylene), polysulfide rubber (polysulfide rubber), polyurethane, EVA film (EVA film), copolyester (co-polyester), and silicone (silicone). Additionally, the over drape material may include silicone, 3M Tegaderm drape material (3MA drape material), an acrylic drape material such as that available from Avery or an incise drape material (incise drape material).
The gasket 128 has a gasket material 130 with a first side 132 and a second patient-facing side 134. A second connection device 136 may be coupled to the second side 134 of the gasket material 130 to releasably connect the gasket 128 to the patient's epidermis 106, or more generally to the skin. The gasket material 130 may be a thin polymer film, such as polyurethane, polyester, silicone, or hydrocolloid, or may include any suitable gasket material. The second connection means 136 holding the gasket 128 in place may be a relatively waterproof material, such asBrand wet-stick adhesive (brand Wet-stick adhesive), hydrocolloids, acrylics, Polyisobutylene (PIB), and the like. The second connection means 136 allows the gasket 128 to remain in place for a long period of time, for example one to two weeks or more, and then to be removed. The over-drape 110 may be reattached to the seal 128 whenever the clinician finds a need to view the wound and reattach the over-drape 110. This allows the seal 128 to remain in place for an extended period of time without significantly stimulating the area of the epidermis 106 surrounding the wound.
The reduced-pressure subsystem 112 includes a reduced-pressure source 140, which reduced-pressure source 140 may take many different forms. The reduced-pressure source 140 provides reduced pressure as part of the system 100. The term "reduced pressure" as used herein generally refers to a pressure that is less than the ambient pressure at the tissue site 104 being treated. In most cases, this reduced pressure will be less than the atmospheric pressure at the location of the patient. Alternatively, the reduced pressure may be less than the hydrostatic pressure of the tissue at the tissue site 104. It is often desirable for the reduced-pressure source 140 to develop a continuous reduced pressure below atmospheric pressure and also be capable of delivering dynamic pressures, i.e., varying the reduced pressure in cycles or operating in a continuous or intermittent mode. The operable range of reduced pressure may vary widely as desired, but will generally include 200 millimeters of mercury (mmHg) below atmospheric pressure. When one refers to increasing reduced pressure, it generally refers to increasing the absolute value of the negative gauge pressure, and similarly, when one refers to decreasing reduced pressure, it generally means that the absolute value of the negative gauge pressure is decreasing.
In the illustrative embodiment of fig. 1, the reduced pressure source 140 is shown with a reservoir region 142 or canister region. An intervening membrane filter, such as a hydrophobic or oleophobic filter, may be placed between the delivery conduit or tubing 144 and the reduced pressure source 140. The intermediate portion 146 of the conduit 144 may have one or more devices, such as device 148. For example, the device 148 may be another fluid reservoir, or a collection member that holds the effluent and other fluids removed. Other examples of devices 148 that may be included on the intermediate portion 146 of the delivery catheter 144 include pressure feedback devices, volume detection systems, blood detection systems, infection detection systems, flow monitoring systems, temperature monitoring systems, and the like. Some of these devices may be integral with the reduced-pressure source 140. For example, the reduced-pressure port 141 on the reduced-pressure source 140 may include a filter member that includes one or more filters, such as an odor filter.
The reduced pressure developed by the reduced-pressure source 140 is delivered through the delivery conduit 144 to a reduced-pressure interface 150, which interface 150 may be an elbow port 152. In one illustrative embodiment, Port 152 is available from kinetic concepts of san Antonio, TexA technology port. The interface 150 allows reduced pressure to be delivered through the over-drape 110 and to be achieved within the sealed space 154. In this illustrative embodiment, the elbow port 152 extends through the over-drape 110 and into the manifold member 108.
Referring now to fig. 2, an illustrative embodiment of a gasket 200 is shown disposed circumferentially around a wound 202. The small margin 204 is shown at the wound edge 206. It should be appreciated from fig. 2 that irregularly shaped wounds, such as wound 202, should be accommodated. One method of accommodating the irregular shape is to join the seal 200 using a gasket tape, i.e., a gasket material with an attachment means that can be applied to the patient like a tape. In this regard, fig. 3 shows an illustrative embodiment of a gasket tape dispenser 300.
The gasket tape dispenser 300 dispenses a gasket 302 or a gasket tape having a gasket material 304 and a coupling device 306. The dispenser 300 can take many forms, but in this embodiment it contains a first chamber portion 308 that holds a roll of gasket tape 302. Thus, the caregiver may dispense the sealing pad 302 around the perimeter of the tissue site proximate the wound 310 on or through the epidermis 311 using the dispenser 300. To do so, the dispenser 300 is moved in the direction indicated by arrow 314. In some instances, it may be desirable to include a releasable backing material on the attachment device 306 until it is ready for application; in such a case, a second chamber 312 (shown in phantom) may be included to collect the removed backing material. The second chamber 312 may include a spring-loaded mandrel to pull the removed backing material onto it. There are many other ways in which the gasket 302 may be dispensed.
Referring again to fig. 2, in operation, after the area around the wound has been properly cleaned and prepared, a caregiver treating the wound 202 can use a dispenser, such as dispenser 300 in fig. 3, to apply the seal gasket 200 around the wound 202 or otherwise place the seal gasket 200 adjacent the wound 202. The seal 200 provides a perimeter around the wound 202 that lasts a long time, which facilitates the attachment of the over-drape and allows the over-drape to be removed without requiring the seal 200 to be removed. By "long lasting," it is meant that the gasket 200 can remain attached and operable for up to one to two weeks or even longer.
Referring again to fig. 1, and continuing with the discussion of one illustrative embodiment of operation, once the seal 128 has been applied in a manner similar to that described with respect to the seal 200 and manifold 108 in place, the over-drape 110 may be placed over the wound 102, and the connection device 124 used to secure the over-drape 110 to the seal 128, and in particular, releasably connect the drape extension 116 to the seal 128. In this example, the attachment means 124 is an adhesive layer 126 and requires removal of the removable backing prior to application. Once the over drape 110 is sealed, it provides a pneumatically sealed space 154. The reduced-pressure interface 150 is applied through the over-drape 110 to allow reduced pressure from the reduced-pressure subsystem 112 to reach the manifold 108. The reduced-pressure subsystem 112 may be activated and reduced pressure provided to the manifold 108 in the sealed space 154.
Referring now to fig. 4, another illustrative embodiment for releasably sealing the over-drape 402 to the first side 404 of the gasket 406 is shown. The seal 406 has a sealing means 408 on a second, patient-facing side 410, which sealing means 408 holds and seals the seal 406 to the patient's epidermis 412 in a prolonged manner. In this illustrative embodiment, the over-drape 402 is secured using a bead of adhesive 414 applied to the first side 404 of the seal 406 and against a second, patient-facing side 416 of the over-drape 402. The bead 414 may be applied by using an applicator similar to a caulking gun. In another illustrative embodiment, a material capable of drying and adhering to the epidermis surrounding the wound of the patient may be sprayed or sprinkled onto the epidermis surrounding the wound of the patient and allowed to dry.
It should be apparent from the foregoing that an invention having significant advantages has been provided. Although this invention is shown in only a few of its forms, it is not so limited but is susceptible to various changes and modifications without departing from the spirit thereof.