Negative pressure wound therapy (NPWT) bandages

Abstract

A negative pressure wound therapy bandage for applying negative pressure to a wound, the bandage comprising: a membrane configured to be placed over the wound so as to form a wound chamber between the membrane and the wound, the membrane including a wound-side surface, an atmosphere-side surface, and an opening extending through the membrane from the wound-side surface to the atmosphere-side surface; and a pump assembly carried by the membrane, the pump assembly comprising a pump body having a wall structure disposed around the pump chamber, at least a portion of the wall structure being elastic, the pump chamber further comprising: a pump body that communicates with the wound chamber through an opening formed in the membrane; and an atmosphere-side passageway extending through the wall structure and fluidly connecting the pump chamber to atmosphere.

Description

Technical Field

[0001] Applicant Guard Medical SAS Inventor Machiel van der Leest John Frederick Cornhill Russell Corwin Reference to Related Prior Patent Applications This patent application is (i) a continuation-in-part of the related prior U.S. Provisional Patent Application No. 16 / 768,481, filed May 21, 2020, by Cornell University and Timothy Johnson et al., titled "MANUALLY-OPERATED NEGATIVE PRESSURE WOUND THERAPY (NPWT) BANDAGE WITH IMPROVED PUMP EFFICIENCY, AUTOMATIC PRESSURE INDICATOR AND AUTOMATIC PRESSURE LIMITER" (Attorney Docket No. CORN-5055PCT US), which claims the benefit of (a) International (PCT) Patent Application No. PCT / US18 / 64178, filed Dec. 6, 2018, by Cornell University and Timothy Johnson et al., titled "MANUALLY-OPERATED NEGATIVE PRESSURE WOUND THERAPY(NPWT) BANDAGE WITH IMPROVED PUMP EFFICIENCY, AUTOMATIC PRESSURE INDICATOR AND AUTOMATIC PRESSURE LIMITER" (Attorney Docket No. CORN-5055 PCT), and which claims the benefit of (1) The preceding U.S. Provisional Patent Application No. 62 / 595,398, “Manually-Operated Negative Pressure Wound Therapy (NPWT) Bandage with Improved Pump Efficiency, Automatic Pressure Indicator and Automatic Pressure Limiter,” filed on December 6, 2017, by Cornell University and Timothy Johnson et al. (Agent Reference Number CORN-50PROV), and, (2) Claiming the interest in the prior U.S. Provisional Patent Application No. 62 / 611,227, “Manually-Operated Negative Pressure Wound Therapy (NPWT) Bandage with Improved Pump Efficiency, Automatic Pressure Indicator and Automatic Pressure Limiter” (Agent Reference Number CORN-55PROV), filed on December 28, 2017, by Cornell University and Timothy Johnson et al., (ii) Claiming the interest in the prior pending U.S. Provisional Patent Application No. 62 / 924,386, “Manually-Operated Negative Pressure Wound Therapy (NPWT) Bandage with Improved Pump Efficiency, Automatic Pressure Indicator and Automatic Pressure Limiter, Including Negative Pressure Decay “Warning State” Indicator” (Agent Reference Number GM-2PROV), filed on 22 October 2019 by Guard Medical SAS and Russell Corwin et al., (iii) Claiming the interest in the prior pending U.S. Provisional Patent Application No. 62 / 924,290, “Manually-Operated Negative Pressure Wound Therapy (NPWT) Bandage with Improved Pump Efficiency, Automatic Pressure Indicator and Automatic Pressure Limiter, Including Canister for Collecting Exudates” (Agent Reference Number GM-3PROV), filed on 22 October 2019 by Guard Medical SAS and Machiel van der Leest et al., (iv) Claiming the interest in the prior pending U.S. Provisional Patent Application No. 62 / 924,432, “Manually-Operated Negative Pressure Wound Therapy (NPWT) Bandage with Improved Pump Efficiency, Automatic Pressure Indicator and Automatic Pressure Limiter, Including Luer Lock for Succession Attachment,” filed on 22 October 2019 by Guard Medical SAS and Machiel van der Leest et al. (Agent Reference Number GM-4PROV), (v) Claiming the interest in the prior pending U.S. Provisional Patent Application No. 62 / 992,667, “Manually-Operated Negative Pressure Wound Therapy (NPWT) Bandage with Improved Pump Efficiency, Automatic Pressure Indicator and Automatic Pressure Limiter, Wherein the Wound Chamber Comprises a Lateral Extension, and Wherein the Pump Assembly Is in Fluid Communication with the Lateral Extension, So That the Pump Assembly Is Laterally Offset From the Wound While Remaining in Fluid Communication with the Wound” (Agent Reference Number GM-8PROV), filed on March 20, 2020 by Guard Medical SAS and Machiel van der Leest et al. (vi) We assert the interest in the prior pending U.S. Provisional Patent Application No. 63 / 081,690, “NEGATIVE PRESSURE WOUND THERAPY (NPWT) BANDAGE,” filed on 22 September 2020 by Guard Medical SAS and Machiel van der Leest et al. (Agent reference number GM-11PROV).

[0002] The nine patent applications identified above are incorporated herein by reference. This invention relates more broadly to bandages, and more particularly to negative pressure wound therapy (NPWT) bandages. [Background technology]

[0003] Bandages are used to provide care for wounds during healing. More specifically, bandages typically provide coverage for wounds to protect them from contaminants and microorganisms during healing. Most bandages also provide a closure function that helps keep the edges of the wound close together during healing. Bandages also often contain gauze or similar material to catch any exudate that comes out of the wound during healing.

[0004] Negative pressure wound therapy (NPWT) dressings apply negative pressure to a wound during healing. This negative pressure helps reduce the likelihood of contaminants and microorganisms entering the wound during healing, helps draw exudate from the wound during healing, and can promote beneficial biological responses at the wound site. More specifically, an NPWT dressing typically comprises (i) an absorbent dressing configured to create a completely sealed chamber ("wound chamber") around the periphery of the wound, (ii) a negative pressure source, and (iii) a conduit extending between the completely sealed wound chamber and the negative pressure source. As a result of this configuration, the absorbent dressing can be applied to the wound to create a completely sealed chamber around the periphery of the wound, and the negative pressure source can apply negative pressure to the completely sealed wound chamber, thereby drawing away any contaminants and microorganisms present at the wound site from the wound, drawing exudate from the wound, and promoting beneficial biological responses at the wound site.

[0005] Most NPWT dressings are part of large and complex NPWT systems in the sense that (i) the absorbent dressing is usually quite large (e.g., large enough to cover a large open wound), (ii) the negative pressure source is usually quite large and is formed and positioned separately from the absorbent dressing (e.g., the negative pressure source usually includes an electric suction pump or vacuum canister), and (iii) the NPWT system usually requires considerable training to use. These NPWT systems also tend to be quite expensive.

[0006] Efforts have been made to provide smaller, simpler, and less expensive NPWT dressings in which the negative pressure source is integrated with the absorbent dressing. Efforts have also been made to provide NPWT dressings in which a manually operated suction pump is integrated with the absorbent dressing, not limited to, but as an example. Unfortunately, current NPWT dressings that integrate the suction pump with the absorbent dressing tend to suffer from a wide range of drawbacks. For example, they have complex designs and / or are expensive, and / or are complicated to use, and / or bulky (including having a high profile), and / or cause additional trauma to the wound during use, and / or have poor pump efficiency, and / or lack a way to indicate the generated negative pressure level, and / or lack a way to limit the generated negative pressure level. Regarding the latter, it should be understood that if excessively high levels of negative pressure are generated, the NPWT dressing may cause trauma to the patient, such as blister formation, capillary leakage, etc.

[0007] Therefore, there is a need for a novel and improved NPWT bandage that is simple, inexpensive, easy to use, small in size (including having a low profile), does not injure the wound during use, has improved pumping efficiency, incorporates an automatic pressure indicator to show the generated negative pressure level, and provides an automatic pressure limiter to limit the generated negative pressure level. [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] These and other objectives of the present invention are addressed by providing and using a novel and improved NPWT bandage that is simple, inexpensive, easy to use, small in size (including having a low profile), does not injure wounds during use, has improved pumping efficiency, incorporates an automatic pressure indicator to show the generated negative pressure level, and provides an automatic pressure limiter to limit the generated negative pressure level. [Means for solving the problem]

[0009] In one preferred embodiment of the present invention, a negative pressure wound therapy (NPWT) bandage for applying negative pressure to a wound, wherein the NPWT bandage is A membrane configured to be placed over a wound, wherein a wound chamber is formed between the membrane and the wound, and the membrane includes a wound-side surface, an atmospheric-side surface, and an opening extending through the membrane from the wound-side surface to the atmospheric-side surface. A pump assembly supported by the above membrane, wherein the pump assembly is A pump body comprising a wall structure arranged around a pump chamber, wherein at least a portion of the wall structure is elastic, A wound-side passage extends through the wall structure and communicates with the wound chamber through the opening formed within the membrane, A wound-side one-way valve is positioned within the wound-side passage, and the wound-side one-way valve is configured to allow fluid to flow from the wound chamber to the pump chamber through the wound-side passage, but to prevent fluid from flowing from the pump chamber to the wound chamber through the wound-side passage. An atmospheric passage extending through the above wall structure and connecting the pump chamber and the atmosphere, A pump assembly comprising: an atmospheric-side one-way valve disposed within the atmospheric-side passage, the atmospheric-side one-way valve being configured to allow fluid to flow from the pump chamber to the atmosphere through the atmospheric-side passage, but to prevent fluid from flowing from the atmosphere to the pump chamber through the atmospheric-side passage; An NPWT bandage is provided, wherein when a compressive force is applied to the wall structure of the pump body, the fluid in the pump chamber is pushed out of the pump chamber through the passage on the atmospheric side, and when the compressive force applied to the wall structure of the pump body is subsequently reduced, the fluid in the wound chamber is drawn back into the pump chamber through the passage on the wound side.

[0010] Preferably, the NPWT bandage is configured such that when the pressure difference between the fluid pressure in the pump chamber and atmospheric pressure is less than a predetermined threshold, the pump body of the pump assembly assumes a substantially fully unfolded configuration, and when the pressure difference between the fluid pressure in the pump chamber and atmospheric pressure exceeds the predetermined threshold, the pump body of the pump assembly assumes a substantially fully folded configuration.

[0011] More preferably, the NPWT bandage is configured such that the pump body abruptly changes state between the substantially fully unfolded configuration and the substantially fully folded configuration, and between the substantially fully folded configuration and the substantially fully unfolded configuration, when the pressure difference crosses a predetermined threshold, thereby effectively creating a substantially "binary state" device.

[0012] In another preferred embodiment of the present invention, a method for applying negative pressure to a wound, The step of preparing a negative pressure wound therapy (NPWT) bandage, the NPWT bandage is A membrane configured to be placed over a wound, wherein a wound chamber is formed between the membrane and the wound, and the membrane includes a wound-side surface, an atmospheric-side surface, and an opening extending through the membrane from the wound-side surface to the atmospheric-side surface. A pump assembly supported by the above membrane, wherein the pump assembly is A pump body comprising a wall structure arranged around a pump chamber, wherein at least a portion of the wall structure is elastic, A wound-side passage extends through the wall structure and communicates with the wound chamber through the opening formed within the membrane, A wound-side one-way valve is positioned within the wound-side passage, and the wound-side one-way valve is configured to allow fluid to flow from the wound chamber to the pump chamber through the wound-side passage, but to prevent fluid from flowing from the pump chamber to the wound chamber through the wound-side passage. An atmospheric passage extending through the above wall structure and connecting the pump chamber and the atmosphere, A pump assembly comprising: an atmospheric-side one-way valve disposed within the atmospheric-side passage, the atmospheric-side one-way valve being configured to allow fluid to flow from the pump chamber to the atmosphere through the atmospheric-side passage, but to prevent fluid from flowing from the atmosphere to the pump chamber through the atmospheric-side passage; Steps include: when a compressive force is applied to the wall structure of the pump body, the fluid in the pump chamber is pushed out of the pump chamber through the passage on the atmospheric side, and when the compressive force applied to the wall structure of the pump body is subsequently reduced, the fluid in the wound chamber is drawn back into the pump chamber through the passage on the wound side; The steps include positioning the negative pressure wound therapy (NPWT) bandage over the wound to form a wound chamber between the membrane and the wound, A method is provided which includes the steps of applying a compressive force to the wall structure of the pump body, and then reducing the compressive force applied to the wall structure of the pump body to apply negative pressure to the wound.

[0013] In another preferred embodiment of the present invention, a negative pressure wound therapy (NPWT) bandage for applying negative pressure to a wound, wherein the NPWT bandage is A membrane configured to be placed over a wound, wherein a wound chamber is formed between the membrane and the wound, and the membrane includes a wound-side surface, an atmospheric-side surface, and an opening extending through the membrane from the wound-side surface to the atmospheric-side surface. A pump supported by the above-mentioned membrane, comprising a wall chamber arranged around the pump chamber, at least a part of the above-mentioned wall chamber being elastic, and further, the above-mentioned pump chamber communicating with the wound chamber through the above-mentioned opening formed in the above-mentioned membrane, and a pump. An NPWT dressing is provided, in which none of the portions of the above-mentioned pump chamber are defined by the above-mentioned wound.

[0014] In another preferred form of the present invention, a negative pressure wound therapy (NPWT) dressing for applying negative pressure to a wound, the above-mentioned NPWT dressing A membrane configured to be placed on the wound, forming a wound chamber between the above-mentioned membrane and the wound, the above-mentioned membrane including a wound-side surface, an atmosphere-side surface, and an opening extending from the wound-side surface to the atmosphere-side surface through the above-mentioned membrane, and a membrane. A pump supported by the above-mentioned membrane and comprising a wall chamber arranged around the pump chamber, at least a part of the above-mentioned wall chamber being elastic, and further, the above-mentioned pump chamber communicating with the wound chamber through the above-mentioned opening formed in the above-mentioned membrane, and a pump. Comprising An NPWT dressing is provided, in which the above-mentioned pump does not apply positive pressure to the wound.

[0015] In another preferred form of the present invention, a negative pressure wound therapy (NPWT) dressing for applying negative pressure to a wound, the above-mentioned NPWT dressing A membrane configured to be placed on the wound, forming a wound chamber between the above-mentioned membrane and the wound, the above-mentioned membrane including a wound-side surface, an atmosphere-side surface, and an opening extending from the wound-side surface to the atmosphere-side surface through the above-mentioned membrane, and a membrane. A pump supported by the above-mentioned membrane and comprising a wall chamber arranged around the pump chamber, at least a part of the above-mentioned wall chamber being elastic, and further, the above-mentioned pump chamber communicating with the wound chamber through the above-mentioned opening formed in the above-mentioned membrane, and a pump. Comprising The above pump is connected to a wound chamber, and an NPWT bandage is provided that prevents a reduction in the volume of the pump chamber from causing a pressure change in the wound chamber.

[0016] In another preferred embodiment of the present invention, the negative pressure wound therapy (NPWT) bandage is constructed to also provide a negative pressure decay "warning state" indicator.

[0017] In one embodiment of the present invention, a negative pressure wound therapy (NPWT) bandage for applying negative pressure to a wound, wherein the NPWT bandage is A membrane configured to be placed over a wound, such that a wound chamber is formed between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending through the membrane from the wound-side surface to the atmospheric-side surface, A pump assembly supported by a membrane, the pump assembly is A pump body comprising a wall structure arranged around a pump chamber, wherein at least a portion of the wall structure is elastic, and further, the pump chamber communicates with a wound chamber through an opening formed in the membrane, An atmospheric-side passage extends through the wall structure and fluidly connects the pump chamber to the atmosphere, Equipped with, A pump assembly is provided, wherein when a compressive force is applied to the wall structure of the pump body, the fluid in the pump chamber is pushed out of the pump chamber through the passage to the atmosphere, and when the compressive force applied to the wall structure of the pump body is subsequently reduced, the fluid in the wound chamber is drawn back into the pump chamber through an opening formed in the membrane. Equipped with, When the pressure difference between the fluid pressure in the pump chamber and atmospheric pressure is below a predetermined threshold, the pump body assumes a substantially fully deployed configuration, thereby indicating that the negative pressure in the wound chamber is below a predetermined threshold; when the pressure difference between the fluid pressure in the pump chamber and atmospheric pressure exceeds a predetermined threshold, the pump body assumes a substantially fully folded configuration, thereby indicating that the negative pressure in the wound chamber exceeds a predetermined threshold. Furthermore, an NPWT bandage is provided, configured to provide a visual indicator that the negative pressure in the wound chamber is decreasing but has not decreased below a predetermined threshold and is not decreasing enough to convert the pump body into its substantially fully deployed configuration.

[0018] In another embodiment of the present invention, a method for applying negative pressure to a wound, The step of preparing a negative pressure wound therapy (NPWT) bandage, the NPWT bandage is A membrane configured to be placed over a wound, such that a wound chamber is formed between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending through the membrane from the wound-side surface to the atmospheric-side surface, A pump assembly supported by a membrane, the pump assembly is A pump body comprising a wall structure arranged around a pump chamber, wherein at least a portion of the wall structure is elastic, and further, the pump chamber communicates with a wound chamber through an opening formed in the membrane, An atmospheric-side passage extends through the wall structure and fluidly connects the pump chamber to the atmosphere, Equipped with, When a compressive force is applied to the wall structure of the pump body, the fluid in the pump chamber is pushed out of the pump chamber through the passage to the atmosphere, and when the compressive force applied to the wall structure of the pump body is subsequently reduced, the fluid in the wound chamber is drawn back into the pump chamber through an opening formed in the membrane. When the pressure difference between the fluid pressure in the pump chamber and atmospheric pressure is below a predetermined threshold, the pump body assumes a substantially fully deployed configuration, thereby indicating that the negative pressure in the wound chamber is below a predetermined threshold; when the pressure difference between the fluid pressure in the pump chamber and atmospheric pressure exceeds a predetermined threshold, the pump body assumes a substantially fully folded configuration, thereby indicating that the negative pressure in the wound chamber exceeds a predetermined threshold. Furthermore, the pump body is configured to provide a visual indicator that the negative pressure in the wound chamber is decreasing but has not decreased below a predetermined threshold and is not decreasing enough to convert the pump body to its substantially fully deployed configuration, It has steps, The steps include positioning the NPWT bandage over the wound to form a wound chamber between the membrane and the wound, The steps include applying a compressive force to the wall structure of the pump body, then reducing the compressive force applied to the wall structure of the pump body to apply negative pressure to the wound, A method is provided that includes this.

[0019] In another preferred embodiment of the present invention, the negative pressure wound therapy (NPWT) bandage includes a canister for collecting exudate.

[0020] In one embodiment of the present invention, a negative pressure wound therapy (NPWT) bandage for applying negative pressure to a wound, wherein the NPWT bandage is A membrane configured to be placed over a wound, such that a wound chamber is formed between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending through the membrane from the wound-side surface to the atmospheric-side surface, A pump assembly supported by a membrane, the pump assembly is A pump body comprising a wall structure arranged around a pump chamber, wherein at least a portion of the wall structure is elastic, A wound-side passage extends through the wall structure and communicates with the wound chamber, An atmospheric passage extends through the wall structure and connects the pump chamber to the atmosphere, A pump assembly comprising, A canister configured to communicate fluidly with a wound chamber and a pump assembly, the canister comprising an internal chamber for collecting exudate exiting the wound chamber, Equipped with, An NPWT bandage is provided, in which the pump assembly is configured to generate negative air pressure within the wound chamber so that exudate from the wound chamber flows out of the wound chamber and into the internal chamber of the canister.

[0021] In another embodiment of the present invention, a method for applying negative pressure to a wound, The step of preparing a negative pressure wound therapy (NPWT) bandage, the NPWT bandage is A membrane configured to be placed over a wound, such that a wound chamber is formed between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending through the membrane from the wound-side surface to the atmospheric-side surface, A pump assembly supported by a membrane, the pump assembly is A pump body comprising a wall structure arranged around a pump chamber, wherein at least a portion of the wall structure is elastic, A wound-side passage extends through the wall structure and communicates with the wound chamber, An atmospheric passage extends through the wall structure and connects the pump chamber to the atmosphere, A pump assembly comprising, A canister configured to communicate fluidly with a wound chamber and a pump assembly, the canister comprising an internal chamber for collecting exudate exiting the wound chamber, Equipped with, The pump assembly is configured to generate negative air pressure within the wound chamber so that exudate from the wound chamber flows out of the wound chamber and into the internal chamber of the canister, and the steps are as follows: The steps include positioning the NPWT bandage over the wound to form a wound chamber between the membrane and the wound, A step of generating negative air pressure within the wound chamber to cause exudate to flow from the wound chamber into the internal chamber of the canister, A method is provided that includes this.

[0022] In another preferred embodiment of the present invention, the negative pressure wound therapy (NPWT) bandage includes a Luer lock for a suction attachment.

[0023] In one embodiment of the present invention, a negative pressure wound therapy (NPWT) bandage for applying negative pressure to a wound, wherein the NPWT bandage is A membrane configured to be placed over a wound, such that a wound chamber is formed between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending through the membrane from the wound-side surface to the atmospheric-side surface, A pump assembly supported by a membrane, the pump assembly is A pump body comprising a wall structure arranged around a pump chamber, wherein at least a portion of the wall structure is elastic, A wound-side passage extends through the wall structure and communicates with the wound chamber through an opening in the membrane, An atmospheric passage extends through the wall structure and connects the pump chamber to the atmosphere, A pump assembly comprising, A suction source configured to be connected to a pump assembly to establish negative air pressure within the wound chamber, Equipped with, An NPWT bandage is provided, wherein when the negative air pressure in the wound chamber is below a predetermined threshold, the pump body is in a substantially fully deployed configuration, and when the negative air pressure in the wound chamber is above a predetermined threshold, the pump body is in a substantially fully folded configuration.

[0024] In another embodiment of the present invention, a method for applying negative pressure to a wound, The step of preparing a negative pressure wound therapy (NPWT) bandage, the NPWT bandage is A membrane configured to be placed over a wound, such that a wound chamber is formed between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending through the membrane from the wound-side surface to the atmospheric-side surface, A pump assembly supported by a membrane, the pump assembly is A pump body comprising a wall structure arranged around a pump chamber, wherein at least a portion of the wall structure is elastic, A wound-side passage extends through the wall structure and communicates with the wound chamber through an opening in the membrane, An atmospheric passage extends through the wall structure and connects the pump chamber and the atmosphere, A pump assembly comprising, A suction source configured to be connected to a pump assembly to establish negative air pressure within the wound chamber, Equipped with, When the negative air pressure in the wound chamber is below a predetermined threshold, the pump body assumes a substantially fully extended configuration, and when the negative air pressure in the wound chamber exceeds a predetermined threshold, the pump body assumes a substantially fully folded configuration, and The steps include positioning the NPWT bandage over the wound to form a wound chamber between the membrane and the wound, The steps include connecting a suction source to a pump assembly to generate negative air pressure within the wound chamber, A method is provided that includes this.

[0025] In another embodiment of the present invention, a negative pressure wound therapy (NPWT) bandage for applying negative pressure to a wound, wherein the NPWT bandage is A membrane configured to be placed over a wound, such that a wound chamber is formed between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending through the membrane from the wound-side surface to the atmospheric-side surface, A pump assembly supported by a membrane, the pump assembly is A pump body comprising a wall structure arranged around a pump chamber, wherein at least a portion of the wall structure is elastic, A wound-side passage extends through the wall structure and communicates with the wound chamber through an opening in the membrane, An atmospheric passage extends through the wall structure and connects the pump chamber to the atmosphere, A pump assembly comprising, A connector for connecting a suction source to the pump assembly in order to establish negative air pressure within the wound chamber, Equipped with, An NPWT bandage is provided, wherein when the negative air pressure in the wound chamber is below a predetermined threshold, the pump body is in a substantially fully deployed configuration, and when the negative air pressure in the wound chamber is above a predetermined threshold, the pump body is in a substantially fully folded configuration.

[0026] In another preferred embodiment of the present invention, the negative pressure wound therapy (NPWT) bandage is provided with a pump assembly that is offset laterally from the wound while maintaining fluid communication with the wound.

[0027] In one embodiment of the present invention, a negative pressure wound therapy (NPWT) bandage for applying negative pressure to a wound, wherein the NPWT bandage is A membrane comprising a first portion configured to be positioned over a wound to form a wound chamber between the membrane and the wound, and a second portion configured to extend laterally away from the wound, wherein the membrane includes a wound-side surface, an atmospheric-side surface, and an opening extending from the wound-side surface to the atmospheric-side surface, the opening being in fluid communication with the wound chamber, and the membrane A pump assembly supported by a second portion of a membrane, the pump assembly is A pump body comprising a wall structure arranged around a pump chamber, wherein at least a portion of the wall structure is elastic, A wound-side passage extends through the wall structure and communicates with the wound chamber through an opening in the membrane, An atmospheric passage extends through the wall structure and connects the pump chamber to the atmosphere, A pump assembly comprising, Equipped with, An NPWT bandage is provided, in which the pump assembly is configured to generate negative air pressure within the wound chamber.

[0028] In another embodiment of the present invention, a method for applying negative pressure to a wound, The step of preparing a negative pressure wound therapy (NPWT) bandage, the NPWT bandage is A membrane comprising a first portion configured to be positioned over a wound to form a wound chamber between the membrane and the wound, and a second portion configured to extend laterally away from the wound, wherein the membrane includes a wound-side surface, an atmospheric-side surface, and an opening extending from the wound-side surface to the atmospheric-side surface, the opening being in fluid communication with the wound chamber, and the membrane A pump assembly supported by a second portion of a membrane, the pump assembly is A pump body comprising a wall structure arranged around a pump chamber, wherein at least a portion of the wall structure is elastic, A wound-side passage extends through the wall structure and communicates with the wound chamber through an opening formed within the membrane, An atmospheric passage extends through the wall structure and connects the pump chamber to the atmosphere, A pump assembly comprising, Equipped with, The pump assembly is configured to generate negative air pressure within the wound chamber, step by step. The steps include positioning the first portion of the NPWT bandage over the wound to form a wound chamber between the membrane and the wound, and positioning the second portion of the membrane on a biological structure offset laterally from the wound, A step of generating negative air pressure inside the wound chamber, A method is provided that includes this.

[0029] In another preferred embodiment of the present invention, a negative pressure wound therapy bandage for covering a wound is provided, the bandage comprising a permeable top layer that captures a layer of foam against the wound, the foam layer having a series of windows that (i) allow direct visualization of the wound and (ii) provide a metric along the length of the bandage for indicating whether the bandage needs to be replaced. The foam layer also comprises periphery serrations that allow the bandage to conform to a curved wound. This novel negative pressure wound therapy bandage can be used with an implemented pump or a pump located remotely from the bandage (or another suction source, e.g., wall suction). This novel bandage can also be used without applying negative pressure to the wound.

[0030] In one embodiment of the present invention, a negative pressure wound therapy (NPWT) bandage for applying negative pressure to a wound, wherein the NPWT bandage is A membrane configured to be placed over a wound so as to form a wound chamber between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending from the wound-side surface to the atmospheric-side surface, the opening being in fluid communication with the wound chamber, The membrane comprises a permeable layer and an absorbent layer, the absorbent layer being positioned on the wound side of the membrane. The absorbent layer includes multiple windows extending through the absorbent layer. Furthermore, multiple windows in the permeable layer and the absorbent layer of the membrane allow for the visualization of the wound through the membrane, A pump assembly supported by a membrane, the pump assembly is A pump body having a wall structure defining a pump chamber, wherein at least a portion of the wall structure is elastic, A wound-side passage extends through the wall structure and communicates with the wound chamber through an opening in the membrane, An atmospheric passage extends through the wall structure and connects the pump chamber to the atmosphere, Equipped with, The pump assembly is configured to generate negative air pressure within the wound chamber, An NPWT bandage is provided that includes the following features.

[0031] In another embodiment of the present invention, a bandage for covering a wound that discharges exudate, the bandage is A membrane configured to be placed over a wound so as to form a wound chamber between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending from the wound-side surface to the atmospheric-side surface, the opening being in fluid communication with the wound chamber, the membrane comprises The membrane comprises a permeable layer and an absorbent layer, the absorbent layer being positioned on the wound side of the membrane. The absorbent layer includes multiple windows extending through the absorbent layer. Furthermore, multiple windows in the permeable layer and the absorbent layer of the membrane provide a bandage that allows for the visualization of the wound through the membrane.

[0032] In another embodiment of the present invention, a method for applying negative pressure to a wound, The step of preparing a negative pressure wound therapy (NPWT) bandage, the NPWT bandage is A membrane configured to be placed over a wound so as to form a wound chamber between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending from the wound-side surface to the atmospheric-side surface, the opening being in fluid communication with the wound chamber, The membrane comprises a permeable layer and an absorbent layer, the absorbent layer being positioned on the wound side of the membrane. The absorbent layer includes multiple windows extending through the absorbent layer. Furthermore, multiple windows in the permeable layer and the absorbent layer of the membrane allow for the visualization of the wound through the membrane, A pump assembly supported by a membrane, the pump assembly is A pump body having a wall structure defining a pump chamber, wherein at least a portion of the wall structure is elastic, A wound-side passage extends through the wall structure and communicates with the wound chamber through an opening formed within the membrane, An atmospheric passage extends through the wall structure and connects the pump chamber to the atmosphere, A pump assembly comprising, Equipped with, The pump assembly is configured to generate negative air pressure within the wound chamber, step by step. The steps include positioning the NPWT bandage over the wound to form a wound chamber between the membrane and the wound, A step of generating negative air pressure inside the wound chamber, The steps include visualizing the absorbent layer of the membrane and determining whether the NPWT bandage needs to be removed from the wound and replaced with a new NPWT bandage, A method is provided that includes this.

[0033] In another embodiment of the present invention, a method for covering a wound that releases exudate, The step is to prepare the bandage, and the bandage is, A membrane configured to be placed over a wound so as to form a wound chamber between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending from the wound-side surface to the atmospheric-side surface, the opening being in fluid communication with the wound chamber, the membrane comprises The membrane comprises a permeable layer and an absorbent layer, the absorbent layer being positioned on the wound side of the membrane. The absorbent layer includes multiple windows extending through the absorbent layer. Furthermore, multiple windows in the permeable layer and the absorbent layer of the membrane allow for the visualization of the wound through the membrane, and The steps include positioning the bandage over the wound to form a wound chamber between the membrane and the wound, The steps include visualizing the absorbent layer of the membrane and determining whether the bandage needs to be removed from the wound and replaced with a new one, A method is provided that includes this.

[0034] These and other objects and features of the present invention are more fully disclosed or revealed by the following detailed description of preferred embodiments of the invention, which should be considered together with the accompanying drawings, where similar numbers refer to similar parts. [Brief explanation of the drawing]

[0035] [Figure 1] This is a schematic diagram showing a novel, improved NPWT bandage formed according to the present invention. [Figure 2] This is a schematic diagram showing a novel, improved NPWT bandage formed according to the present invention. [Figure 3] This is a schematic diagram showing a novel, improved NPWT bandage formed according to the present invention. [Figure 4] This is a schematic diagram showing a novel, improved NPWT bandage formed according to the present invention. [Figure 4A] This schematic diagram shows the maximum negative pressure that can be established for two different sizes of wound chambers (i.e., a 7.5 mL wound chamber and a 15 mL wound chamber) using (i) a deformable pump body having two one-way valves (one one-way valve located on each side of the deformable pump body) and (ii) a deformable pump body having a single one-way valve (Note: In the comparison shown in Figure 4A, the volume of the pump chamber of the deformable pump body with one one-way valve is the same as the volume of the pump chamber of the deformable pump body with two one-way valves). [Figure 5] Figures 1 to 4 are schematic diagrams showing the pump body of the NPWT bandage pump assembly in a substantially fully unfolded configuration. [Figure 6] Figures 1 to 4 are schematic diagrams showing the pump body of the NPWT bandage pump assembly in a substantially completely folded configuration. [Figure 7] Figures 1 to 4 are schematic diagrams illustrating how the pump body of the NPWT bandage pump assembly abruptly changes state between its substantially fully unfolded configuration and its substantially fully folded configuration. [Figure 8] This is a schematic diagram illustrating how the pump body of a conventional NPWT bandage pump assembly gradually changes state between its substantially fully unfolded configuration and its substantially fully folded configuration. [Figure 9] Figures 1 to 4 are schematic diagrams illustrating exemplary use of the novel, improved NPWT bandage. [Figure 10] Figures 1 to 4 are schematic diagrams illustrating exemplary use of the novel, improved NPWT bandage. [Figure 11] Figures 1 to 4 are schematic diagrams illustrating exemplary use of the new, improved NPWT bandage (note that in Figure 11, the removable cap 100 (see below) has been removed from the drawing for clarity). [Figure 12] Figures 1 to 4 are schematic diagrams illustrating exemplary use of the novel, improved NPWT bandage. [Figure 13] Figures 1 to 4 are schematic diagrams illustrating exemplary use of the novel, improved NPWT bandage. [Figure 14] Figures 1 to 4 are schematic diagrams illustrating exemplary use of the new, improved NPWT bandage (note that in Figure 14, the removable cap 100 (see below) has been removed from the drawing for clarity). [Figure 15] Figures 1 to 4 are schematic diagrams illustrating exemplary use of the new, improved NPWT bandage (note that in Figure 15, the removable cap 100 (see below) has been removed from the drawing for clarity). [Figure 16] Figures 1 to 4 are schematic diagrams illustrating exemplary use of the new, improved NPWT bandage (note that in Figure 16, the removable cap 100 (see below) has been removed from the drawing for clarity). [Figure 17] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention. [Figure 18] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention. [Figure 19] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention. [Figure 20] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention. [Figure 20A]This is a schematic diagram showing how the configuration of the pump body changes during use (note that, for clarity, only the outer boundary of the pump's side wall 65 is shown in Figure 20A, and the pump's flange 75 and neck 77 are omitted). [Figure 21] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention. [Figure 22] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention. [Figure 23] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention. [Figure 24] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention. [Figure 25] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention. [Figure 26] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention, in which the pump body is constructed to also provide a negative pressure decay "warning state" indicator. [Figure 27] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention, in which the pump body is constructed to also provide a negative pressure decay "warning state" indicator. [Figure 28] This is a schematic diagram showing how the configuration of the pump body equipped with a negative pressure decay "warning state" indicator changes during use (note that in Figure 28, only the outer boundary of the pump's side wall is shown for clarity). [Figure 29] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention. [Figure 30] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention. [Figure 31] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention. [Figure 32]This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention. [Figure 33] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention. [Figure 34] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention. [Figure 35] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention, wherein the wound chamber includes a lateral extension, the pump assembly is in fluid communication with the lateral extension, and the pump assembly is offset laterally from the wound while maintaining fluid communication with the wound. [Figure 36] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention, wherein the wound chamber includes a lateral extension, the pump assembly is in fluid communication with the lateral extension, and the pump assembly is offset laterally from the wound while maintaining fluid communication with the wound. [Figure 37] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention, wherein the wound chamber includes a lateral extension, the pump assembly is in fluid communication with the lateral extension, and the pump assembly is offset laterally from the wound while maintaining fluid communication with the wound. [Figure 38] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention, wherein the wound chamber includes a lateral extension, the pump assembly is in fluid communication with the lateral extension, and the pump assembly is offset laterally from the wound while maintaining fluid communication with the wound. [Figure 39] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention, wherein the wound chamber includes a lateral extension, the pump assembly is in fluid communication with the lateral extension, and the pump assembly is offset laterally from the wound while maintaining fluid communication with the wound. [Figure 40]This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention, wherein the wound chamber includes a lateral extension, the pump assembly is in fluid communication with the lateral extension, and the pump assembly is offset laterally from the wound while maintaining fluid communication with the wound. [Figure 41] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention, wherein the wound chamber includes a lateral extension, the pump assembly is in fluid communication with the lateral extension, and the pump assembly is offset laterally from the wound while maintaining fluid communication with the wound. [Figure 42] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention, wherein the wound chamber includes a lateral extension, the pump assembly is in fluid communication with the lateral extension, and the pump assembly is offset laterally from the wound while maintaining fluid communication with the wound. [Figure 43] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention, wherein the wound chamber includes a lateral extension, the pump assembly is in fluid communication with the lateral extension, and the pump assembly is offset laterally from the wound while maintaining fluid communication with the wound. [Figure 44] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention, wherein the wound chamber includes a lateral extension, the pump assembly is in fluid communication with the lateral extension, and the pump assembly is offset laterally from the wound while maintaining fluid communication with the wound. [Figure 45] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention, wherein the wound chamber includes a lateral extension, the pump assembly is in fluid communication with the lateral extension, and the pump assembly is offset laterally from the wound while maintaining fluid communication with the wound. [Figure 46]This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention, wherein the wound chamber includes a lateral extension, the pump assembly is in fluid communication with the lateral extension, and the pump assembly is offset laterally from the wound while maintaining fluid communication with the wound. [Figure 46A] This is a schematic diagram showing another novel, improved NPWT bandage formed according to the present invention, wherein the wound chamber includes a lateral extension, the pump assembly is in fluid communication with the lateral extension, and the pump assembly is offset laterally from the wound while maintaining fluid communication with the wound. [Figure 47] This is a schematic diagram showing another novel improved NPWT bandage formed according to the present invention, which includes a permeable top layer that captures a layer of foam against the wound, the foam layer having a series of windows that (i) allow direct visualization of the wound and (ii) provide a metric along the length of the bandage for indicating whether the bandage needs to be replaced, and further the foam layer also includes periphery serrations that allow the bandage to conform to a curved wound, and in this embodiment of the present invention, the NPWT bandage includes an implemented pump that is offset laterally from the wound. [Figure 48] This is a schematic diagram showing another novel improved NPWT bandage formed according to the present invention, which includes a permeable top layer that captures a layer of foam against the wound, the foam layer having a series of windows that (i) allow direct visualization of the wound and (ii) provide a metric along the length of the bandage for indicating whether the bandage needs to be replaced, and further the foam layer also includes periphery serrations that allow the bandage to conform to a curved wound, and in this embodiment of the present invention, the NPWT bandage includes an implemented pump that is offset laterally from the wound. [Figure 49]This is a schematic diagram showing another novel improved NPWT bandage formed according to the present invention, which includes a permeable top layer that captures a layer of foam against the wound, the foam layer having a series of windows that (i) allow direct visualization of the wound and (ii) provide a metric along the length of the bandage for indicating whether the bandage needs to be replaced, and further the foam layer also includes periphery serrations that allow the bandage to conform to a curved wound, and in this embodiment of the present invention, the NPWT bandage includes an implemented pump that is offset laterally from the wound. [Figure 50] Figures 47, 48, and 49 are schematic diagrams showing further details of the foam layers. [Figure 51] Figure 47 is a schematic diagram showing various levels of exudate in the foam layer of the bandage. [Figure 52] Figure 47 is a schematic diagram showing various levels of exudate in the foam layer of the bandage. [Figure 53] This schematic diagram illustrates how the window in the foam layer allows healthcare professionals to position the bandage along the wound line. [Figure 54] This schematic diagram illustrates how the window in the foam layer allows healthcare professionals to position the bandage along the wound line. [Figure 55] This is a schematic diagram showing the periphery serrations formed on the foam layer, which allow the bandage to curve to follow the curved path of the wound. [Figure 56] These are schematic diagrams showing how the NPWT bandages in Figures 47, 48, and 49 can be modified to position the pump mounted on a portion of the foam. [Figure 57] These are schematic diagrams showing how the NPWT bandages in Figures 47, 48, and 49 can be modified to position the pump mounted on a portion of the foam. [Figure 58]Figures 56 and 57 are schematic diagrams showing how the NPWT bandage can be modified to remove the attached pump, thereby providing a general-purpose bandage, which includes a permeable top layer that captures a layer of foam against the wound, the foam layer having a series of windows that (i) allow direct visualization of the wound and (ii) provide a metric along the length of the bandage to indicate whether the bandage needs to be changed, and further the foam layer also includes periphery serrations that allow the bandage to conform to curved wounds. [Figure 59] Figures 56 and 57 are schematic diagrams showing how the NPWT bandage can be modified to remove the attached pump, thereby providing a general-purpose bandage, which includes a permeable top layer that captures a layer of foam against the wound, the foam layer having a series of windows that (i) allow direct visualization of the wound and (ii) provide a metric along the length of the bandage to indicate whether the bandage needs to be changed, and further the foam layer also includes periphery serrations that allow the bandage to conform to curved wounds. [Figure 60] Figures 56 and 57 are schematic diagrams showing how the NPWT bandage can be modified to remove the attached pump, thereby providing a general-purpose bandage, which includes a permeable top layer that captures a layer of foam against the wound, the foam layer having a series of windows that (i) allow direct visualization of the wound and (ii) provide a metric along the length of the bandage to indicate whether the bandage needs to be changed, and further the foam layer also includes periphery serrations that allow the bandage to conform to curved wounds. [Modes for carrying out the invention]

[0036] The present invention includes providing and using a novel and improved NPWT bandage that is simple, inexpensive, easy to use, small in size (including having a low profile), does not injure wounds during use, has improved pumping efficiency, incorporates an automatic pressure indicator to show the generated negative pressure level, and provides an automatic pressure limiter to limit the generated negative pressure level.

[0037] General manual negative pressure wound therapy (NPWT) bandages More specifically, referring first to Figures 1 to 4, a manually operated negative pressure wound therapy (NPWT) bandage 5 is shown, which has improved pump efficiency and includes an automatic pressure indicator to show the generated negative pressure level and an automatic pressure limiter to limit the generated negative pressure level.

[0038] An NPWT bandage 5 generally comprises a membrane (or sheet) 10 and a pump assembly 15.

[0039] As will be discussed later, the membrane 10 is configured to create a completely sealed chamber around the periphery of the wound, thereby defining the wound chamber.

[0040] As will be discussed later, the pump assembly 15 applies negative pressure to a fully sealed wound chamber, thereby drawing away any contaminants and microorganisms present at the wound site, drawing out exudate, and promoting beneficial biological responses at the wound site. Importantly, as will be discussed later, the pump assembly 15 is designed to provide improved pumping efficiency, an automatic pressure indicator to show the generated negative pressure level, and an automatic pressure limiter to limit the generated negative pressure level.

[0041] film More specifically, the membrane 10 comprises a flat, planar sheet 20 formed from a flexible, substantially air-impermeable material, such as Tegaderm from 3M Company (also known as Minnesota Mining and Manufacturing Company), thereby allowing the membrane 10 to conform to the contours of the body and form a substantially airtight chamber (i.e., wound chamber) around the periphery of the wound. The membrane 10 is characterized by a wound-side surface 25 and an atmospheric-side surface 30. The membrane 10 is also characterized by an outer edge 35 and an inner opening 40.

[0042] The adhesive 45 is preferably placed on the wound-side surface 25 of the film 10. The release liner 50 is preferably placed on the wound-side surface 25 over the adhesive 45 to keep the adhesive 45 covered until use.

[0043] The removable reinforcement 55 is preferably positioned on the atmospheric surface 30 of the membrane 10. The removable reinforcement 55 facilitates the handling of the NPWT bandage 5 (and particularly the membrane 10) while removing the NPWT bandage from its sterile packaging and while positioning the NPWT bandage around the wound. The removable reinforcement 55 is intended to be removed from the membrane 10 once the NPWT bandage 5 is secured around the wound site. The removable reinforcement 55 may be provided as a single element, and more preferably as a pair of elements to facilitate removal from the membrane 10 after the NPWT bandage 5 has been secured around the wound site.

[0044] Pump Assembly The pump assembly 15 comprises a pump body 60 having a generally cylindrical shape and comprising side walls 65 and an inner chamber 70. The pump body 60 is formed from an elastic material, such as silicone, so that the side walls 65 can be compressed inward by the application of an external force (e.g., squeezing by the user's thumb and index finger), and then, when the external force is removed, attempt to return to their original uncompressed state. The pump flange 75 is preferably formed on one side of the pump body 60. As will be discussed in more detail below, the pump body 60 extends through an inner opening 40 of the membrane 10, and the upper surface of the pump flange 75 is fixed to the wound-side surface 25 of the membrane 10, so that the pump assembly 15 is fixed to and supported by the membrane 10. The pump flange 75 is preferably formed from a flexible material so that it can conform to the contour of the body (at least to a limited extent). In one embodiment of the present invention, the pump body 60 and the pump flange 75 are integrally formed from the same material, such as silicone. In one preferred embodiment of the present invention, the side wall 65 of the pump body 60 and the pump flange 75 meet at the neck portion 77 (Figure 5). In one preferred embodiment of the present invention, the neck portion 77 has a relatively small width relative to the entire diameter of the pump body 60, and a recess 78 extends inward between the membrane 10 and the pump body 60, thereby mounting the pump body 60 to the pump flange 75, but still allowing it to freely compress / expand radially with minimal interference from the pump flange 75. A wound-side passage 80 is formed within the pump body 60 and communicates with the inner chamber 70. The wound-side passage 80 opens to the outside of the pump body 60 at the wound-side port 82. An atmospheric-side passage 85 is formed within the pump body 60 and similarly communicates with the inner chamber 70. The atmospheric-side passage 85 opens to the outside of the pump body 60 at the atmospheric-side port 87.

[0045] The wound-side one-way valve 90 is located within the wound-side passage 80 and is configured to allow fluid to enter the inner chamber 70 through the wound-side passage 80, but to prevent fluid from leaving the inner chamber 70 through the wound-side passage 80.

[0046] The atmospheric-side one-way valve 95 is located in the atmospheric-side passage 85 and is configured to allow fluid to exit the inner chamber 70 through the atmospheric-side passage 85, but to prevent fluid from entering the inner chamber 70 through the atmospheric-side passage 85.

[0047] As a result of this construction, when the pump body 60 of the pump assembly 15 is squeezed manually (for example, by applying compressive force to the side walls 65 of the pump body 60 using the user's thumb and index finger), the fluid (e.g., air, liquid, etc.) in the inner chamber 70 is pushed out of the inner chamber 70 through the atmospheric passage 85. Subsequently, when the pump body 60 of the pump assembly 15 is released (for example, by relieving the compressive force applied to the side walls 65 of the pump body 60 by the user's thumb and index finger), the fluid (e.g., air, liquid, etc.) (e.g., air, liquid, etc. in the wound chamber) beneath the wound-side surface 25 of the membrane 10 is drawn into the inner chamber 70 through the wound-side passage 80 as the elastic side walls of the pump body return to their uncompressed state.

[0048] It should be noted that when the pump body 60 of the pump assembly 15 is manually squeezed, the fluid (e.g., air, liquid, etc.) in the inner chamber 70 is prevented from leaving the inner chamber 70 through the wound-side passage 80 due to the one-way operation of the wound-side one-way valve 90, and when the pump body 60 of the pump assembly 15 is subsequently released, air from the atmosphere is prevented from being drawn into the inner chamber 70 through the atmospheric-side passage 85 due to the one-way operation of the atmospheric-side one-way valve 95.

[0049] Therefore, it can be understood that by repeatedly manually squeezing and releasing the pump body 60 of the pump assembly 15, a suction force is applied to the wound chamber located beneath the wound-side surface 25 of the membrane 10, thereby generating negative pressure at the wound site.

[0050] It should be understood that the present invention's method of preparing a pump assembly using two one-way valves arranged in-line on both sides of a deformable pump body (i.e., a wound-side one-way valve 90 and an atmospheric-side one-way valve 95, both located on either side of the deformable pump body 60) offers several significant advantages that are not achievable with the prior art method of preparing a deformable pump body using a single one-way valve.

[0051] More specifically, as discussed below, the present invention, which prepares the pump assembly using two one-way valves arranged in-line on both sides of a deformable pump body (i.e., a wound-side one-way valve 90 and an atmospheric-side one-way valve 95, both located on either side of the deformable pump body 60), makes it possible to establish substantially the same maximum negative pressure at the wound site regardless of the size of the wound chamber. This is not achievable with the conventional method of preparing a deformable pump body using a single one-way valve.

[0052] In addition, the present invention's method of preparing the pump assembly using two one-way valves arranged in-line on both sides of a deformable pump body (i.e., a wound-side one-way valve 90 and an atmospheric-side one-way valve 95, both located on either side of the deformable pump body 60) allows a certain selected maximum negative pressure to be achieved at the wound site that is greater than what can be achieved at the wound site using a deformable pump body having a single one-way valve (reflecting the prior art method).

[0053] More specifically, Figure 4A shows the maximum negative pressure that can be established for two different sizes of wound chambers (i.e., a 7.5 mL wound chamber and a 15 mL wound chamber) using (i) a deformable pump body having two one-way valves (one one-way valve located on each side of the deformable pump body) and (ii) a deformable pump body having a single one-way valve (Note: In the comparison shown in Figure 4A, the volume of the pump chamber of the deformable pump body with one one-way valve is the same as the volume of the pump chamber of the deformable pump body with two one-way valves).

[0054] Figure 4A illustrates several important aspects of the present invention.

[0055] Firstly, Figure 4A shows that by using a deformable pump body with two one-way valves (one one-way valve on each side of the deformable pump body) to evacuate the wound chamber, substantially the same maximum negative pressure is established within the wound chamber regardless of the size of the wound chamber (i.e., approximately -20.00 kPa (-150.0 mmHg) for a 7.5 mL wound chamber and approximately -20.00 kPa (-150.0 mmHg) for a 15 mL wound chamber), whereas this is not the case when using a deformable pump body with a single one-way valve (i.e., approximately -10.67 kPa (-80.0 mmHg) for a 7.5 mL wound chamber and approximately -6.67 kPa (-50.0 mmHg) for a 15 mL wound chamber). Therefore, the NPWT bandage of the present invention makes it possible to establish substantially the same maximum negative pressure at the wound site regardless of the size of the wound chamber, whereas conventional NPWT bandages do not.

[0056] This unique feature of the present invention is clinically important because (i) it is usually desirable to establish a selected maximum negative pressure at the wound site (e.g., about 8.00 kPa (60 mmHg) to about 24.00 kPa (180 mmHg)), and (ii) it is usually difficult to know the volume of the wound chamber in advance (due to variations in medical applications and patient anatomical structures, etc.). For this reason, the NPWT bandage of the present invention allows substantially the same maximum negative pressure to be established at the wound site regardless of the size of the wound chamber, thus enabling the NPWT bandage to be designed in advance (e.g., at the time of manufacture) to establish a selected maximum negative pressure at the wound site, whereas conventional NPWT bandages do not.

[0057] Secondly, Figure 4A shows that by evacuating the wound chamber using a deformable pump body having two one-way valves (one one-way valve located on each side of the deformable pump body), a substantially higher maximum negative pressure (i.e., approximately -20.00 kPa (-150 mmHg) for a 7.5 mL wound chamber and approximately -20.00 kPa (-150 mmHg) for a 15 mL wound chamber) is established within the wound chamber than the maximum negative pressure that can be established using a deformable pump body with a single one-way valve (i.e., approximately -10.67 kPa (-80.0 mmHg) for a 7.5 mL wound chamber and approximately -6.67 kPa (-50.0 mmHg) for a 15 mL wound chamber). Thus, the NPWT bandage of the present invention enables the establishment of a substantially higher maximum negative pressure at the wound site.

[0058] It should also be noted that the pressure inside the inner chamber 70 of the pump body 60 is usually equal to the pressure below the wound-side surface 25 of the membrane 10 (i.e., the pressure inside the inner chamber 70 of the pump body 60 is usually equal to the pressure inside the wound chamber).

[0059] In one preferred embodiment of the present invention, the pump assembly 15 also includes a removable cap 100. The removable cap 100 is configured to selectively close the atmospheric passage 85 to the fluid flow when the removable cap 100 is inserted into the atmospheric passage 85 so as to close the atmospheric port 87.

[0060] The pump assembly 15 is mounted on the membrane 10 such that the pump assembly 15 is supported by the membrane 10. More specifically, the pump assembly 15 is mounted on the membrane 10 by (i) passing the pump body 60 of the pump assembly 15 through the inner opening 40 of the membrane 10, (ii) bringing the pump flange 75 facing the wound-side surface 25 of the membrane 10, and then (iii) attaching the pump flange 75 to the wound-side surface 25 of the membrane 10 (e.g., by adhesive, gluing, etc.). Note that the pump assembly 15 and the membrane 10 form a substantially airtight connection.

[0061] Importantly, the pump body 60 of the pump assembly 15 is as discussed below. (i) Improved pump efficiency, (ii) an automatic pressure indicator that shows the generated negative pressure level, (iii) Carefully configured to provide an automatic pressure limiter for limiting the level of negative pressure generated.

[0062] More specifically, the pump body 60 of the pump assembly 15 is, (i) A substantially fully unfolded configuration in which the side walls 65 of the pump body 60 and the inner chamber 70 of the pump body 60 have a substantially circular cross-section (see Figure 5) when the pressure difference between the fluid pressure in the inner chamber 70 and atmospheric pressure is less than a given threshold, (ii) The pump body abruptly changes state between a substantially fully deployed configuration and a configuration in which the side wall 65 of the pump body 60 is bent inward (see Figure 6) when the pressure difference between the fluid pressure in the inner chamber 70 and atmospheric pressure exceeds a given threshold.

[0063] In detail, when the pressure difference between the fluid pressure in the inner chamber 70 and atmospheric pressure is less than a given threshold, the pump body 60 of the pump assembly 15 is in a substantially fully deployed configuration. As shown in Figure 5, when the pressure difference between the fluid pressure in the inner chamber 70 and atmospheric pressure exceeds a predetermined threshold, the pump body 60 of the pump assembly 15 takes on a substantially completely folded configuration (Figure 6).

[0064] Importantly, the pump body 60 of the pump assembly 15 is configured to abruptly change state between a substantially fully deployed configuration (Figure 5) and a substantially fully folded configuration (Figure 6) when the pressure difference between the fluid pressure in the inner chamber 70 and atmospheric pressure crosses the given threshold described above. See Figure 7, a graph showing the relationship between the diameter of the side wall 65 of the pump body 60 and the pressure difference between the fluid pressure in the inner chamber 70 and atmospheric pressure. Thus, the pump assembly 15 is configured, in detail, to behave essentially as a substantially "binary" device, i.e., substantially fully deployed (Figure 5) or substantially fully folded (Figure 6). In this regard, as used herein, the term "substantially "binary" device" is intended to refer to a device that tends to take either a substantially fully deployed state or a substantially fully folded state, and as used herein, the term "substantially "binary" behavior" is intended to refer to a device that tends to take either a substantially fully deployed state or a substantially fully folded state.

[0065] It should be noted that the substantially "binary state" behavior of the pump body 60 is a result of forming the pump body using side walls 65 having a substantially circular cross-section, which gives the pump body an "overcenter" deformation characteristic. That is, the side walls of the pump body 60 have a "collapse" mode in which it abruptly transitions from a substantially fully unfolded configuration to a substantially fully folded configuration, and a "restoration" mode in which it abruptly transitions from a substantially fully folded configuration to a substantially fully unfolded configuration. See Figure 7. The side wall 65 of the pump body 60 and the pump flange 75 meet at the neck portion 77 (Figure 5), the neck portion 77 has a relatively small width relative to the entire diameter of the pump body 60, and the recess 78 forms the pump assembly 15 such that it extends inward between the membrane 10 and the pump body 60, so that the pump body 60 has a substantially circular cross-section substantially over its entire circumference, and the pump body 60 can be compressed / expanded radially with minimal interference from the pump flange 75, thereby allowing the pump body 60 to exhibit substantially "binary" behavior.

[0066] Furthermore, conventional methods of forming the pump body using a dome-shaped or square pump configuration do not bring about abrupt changes in the state of the pump body. Rather, these conventional dome-shaped or square pump configurations bring about a more gradual change in the state of the pump body between an expanded configuration and a folded configuration when the pressure difference between the fluid pressure in the inner chamber and atmospheric pressure changes. See Figure 8, a graph showing the relationship between the diameter of the side wall of a pump body having a dome-shaped or square configuration and the pressure difference between the fluid pressure in the inner chamber of the pump body and atmospheric pressure.

[0067] As a result of carefully configuring the side walls 65 of the pump body 60 of the pump assembly 15 to exhibit this abrupt change of state, the pump assembly 15 is able to provide improved pump efficiency, an automatic pressure indicator to show the generated negative pressure level, and an automatic pressure limiter to limit the generated negative pressure level.

[0068] More specifically, by configuring the pump body 60 of the pump assembly 15 to abruptly change state between a substantially fully deployed configuration and a substantially fully folded configuration when the pressure difference between the fluid pressure in the inner chamber 70 and atmospheric pressure crosses a given threshold, the pump assembly 15 effectively returns to the substantially fully deployed configuration as long as the pressure difference between the fluid pressure in the inner chamber 70 and atmospheric pressure is below a given threshold. As a result, as long as the pressure difference between the fluid in the inner chamber 70 and atmospheric pressure is below a given threshold, the pump assembly 15 returns to the substantially fully deployed configuration during compression (i.e., squeezing), thus maintaining a fully effective state when applying negative pressure to the wound chamber. This is in contrast to the performance of conventional devices in which, as the pressure difference between the fluid pressure in the inner chamber of the pump assembly changes, the pump body exhibits a gradual change of state between the deployed and folded configurations, thereby progressively reducing the efficiency of the pump assembly as the pressure in the wound chamber decreases. The reason for this is that as negative pressure is generated within the wound chamber, the pump body gradually returns slightly to its fully deployed configuration, thereby reducing the amount of fluid that the pump assembly can discharge each time the pump body is squeezed. In other words, in conventional devices, the efficiency of the pump assembly decreases as negative pressure is generated within the wound chamber.

[0069] In a related system, the pump assembly 15 can function as an automatic pressure indicator for the generated negative pressure level by configuring the pump body 60 to abruptly change state between a substantially fully deployed configuration and a substantially fully folded configuration when the pressure difference between the fluid pressure in the inner chamber 70 and atmospheric pressure crosses a given threshold; that is, as long as the pump body 60 of the pump assembly 15 returns to the substantially fully deployed configuration during squeezing, it is readily apparent to the observer that the pressure in the inner chamber 70 (and therefore the pressure in the wound chamber) falls below a given level. This is in stark contrast to the performance of prior art devices, in which the pump body 60 undergoes a gradual change of state between the deployed and folded configurations when the pressure difference between the fluid pressures in the inner chamber of the pump assembly changes, in which case the pump assembly cannot function as an automatic pressure indicator for the generated negative pressure level.

[0070] In a related system, the pump assembly 15 can function as an automatic pressure limiter to limit the generated negative pressure level by configuring the pump body 60 to abruptly change state between a substantially fully deployed configuration and a substantially fully folded configuration when the pressure difference between the fluid pressure in the inner chamber 70 and atmospheric pressure crosses a given threshold. This is because, as soon as the pump body 60 takes the substantially fully folded configuration, the pump assembly 15 can no longer pump fluid from the wound chamber, effectively deactivating the pump assembly. This is in stark contrast to the performance of the prior art, where the pump body results in a gradual change of state between the deployed and folded configurations when the pressure difference between the fluid pressures in the inner chamber changes, because the pump assembly is not effectively deactivated at a given pressure difference.

[0071] It should be understood that the pressure difference required to transition the pump body 60 between a substantially fully deployed configuration and a substantially fully folded configuration (i.e., the “given threshold” mentioned above) can be “tuned” to a specific level by varying one or more properties of the pump body 60, for example, by forming the side walls 65 of the pump body 60 from a material having a specific durometer, adjusting the thickness of the side walls 65 of the pump body 60, or adjusting the diameter of the inner chamber 70 of the pump body 60.

[0072] In general, it has been found that excellent therapeutic results can be achieved when the pressure difference required to transition the pump body between a substantially fully deployed configuration and a substantially fully folded configuration (i.e., the "given threshold" mentioned above) is approximately 8.00 kPa (60 mmHg) to approximately 24.00 kPa (180 mmHg). In other words, it has been found that excellent therapeutic results can be achieved when the pump body 60 transitions between a substantially fully deployed configuration (Figure 5) and a substantially fully folded configuration (Figure 6) at a negative pressure of approximately 8.00 kPa (60 mmHg) to approximately 24.00 kPa (180 mmHg). If the pump body 60 transitions between the two states at a lower pressure (i.e., if the pump body 60 transitions at a negative pressure lower than approximately 8.00 kPa (60 mmHg)), it is thought that insufficient suction force is provided at the wound site to effectively draw contaminants and microorganisms from the wound site and / or effectively draw exudate from the wound site and / or promote beneficial biological responses at the wound site. Furthermore, if the pump body 60 transitions between the two states at a higher pressure (i.e., if the pump body 60 transitions at a negative pressure higher than approximately 24.00 kPa (180 mmHg)), it is thought that the suction force provided at the wound site may cause tissue trauma (e.g., blister formation, capillary leakage, etc.).

[0073] In one preferred embodiment of the present invention, the pump body 60 of the pump assembly 15 is configured to abruptly transition between a substantially fully deployed configuration and a substantially fully folded configuration when the pressure difference between the fluid pressure in the inner chamber 70 and atmospheric pressure exceeds 10.67 kPa (80 mmHg). Therefore, in this embodiment of the present invention, as long as the negative pressure in the wound chamber is less than 90.66 kPa (680 mmHg) (assuming atmospheric pressure is 101.33 kPa (760 mmHg)), the pump assembly 15 returns to a substantially fully unfolded configuration between squeezing of the pump body, maintaining pump efficiency when applying suction force to the wound chamber. As soon as the negative pressure in the wound chamber exceeds 90.66 kPa (680 mmHg) (assuming atmospheric pressure is 101.33 kPa (760 mmHg)), the pump assembly 15 assumes a substantially fully folded configuration and acts as an automatic pressure indicator to show that the negative pressure level generated at the wound site has exceeded 10.67 kPa (80 mmHg), and automatically deactivates the pump assembly 15 so that the negative pressure level generated at the wound site cannot exceed 10.67 kPa (80 mmHg).

[0074] It should be noted that the NPWT bandage 5 has a low profile as long as the pump body 60 of the pump assembly 15 has a substantially cylindrical configuration.

[0075] It should also be noted that, as long as the pump body 60 of the pump assembly 15 is configured to be squeezed between the user's thumb and index finger, the compressive force applied to the pump body 60 is applied parallel to the surface of the skin, so as not to inflict trauma on the wound during use (i.e., while pumping the pump assembly 15). This is in stark contrast to conventional NPWT bandages that use a dome-shaped configuration and require the compressive force to be applied toward the wound.

[0076] Exemplary use In one preferred embodiment of the present invention, referring here to Figures 9 to 16, the NPWT bandage 5 is intended to be used as follows:

[0077] Firstly, the NPWT bandages 5 are removed from the box. In one embodiment of the present invention, each individual NPWT bandage 5 is housed in a separate sterile package, and multiple sterile packages are housed in the box. See Figure 9.

[0078] Next, the NPWT bandage 5 is removed from its sterile packaging so that it is ready for use (Figure 11) (Figure 10).

[0079] To apply the NPWT bandage 5 to the wound site, the release liner 50 is removed from the wound-side surface 25 of the membrane 10. See Figure 12. Next, the NPWT bandage 5 is positioned against the patient's skin, thereby positioning the wound-side surface 25 of the membrane 10 against the wound, and the adhesive 45 secures the NPWT bandage 5 to the patient's skin, thereby forming a substantially airtight seal with the patient's skin around the periphery of the wound chamber. See Figure 13.

[0080] Note that when the NPWT bandage 5 is applied to the patient's skin, the wound-side port 82 of the wound-side passage 80 of the pump assembly 15 is open to the wound chamber.

[0081] It should also be noted that before placing the NPWT bandage 5 on the patient's skin, a layer 102 of gauze (or other absorbent wound dressing) may be placed on the wound site so that the layer of gauze (or other absorbent wound dressing) is interposed between the wound and the wound-side passage 80 of the pump assembly 15. As a result, exudate from the wound is absorbed by the gauze (or other absorbent wound dressing). If desired, the layer 102 of gauze (or other absorbent wound dressing) may be attached (i.e., fixed) to the wound-side surface of the membrane 10, for example, during manufacturing, so that the layer of gauze (or other absorbent wound dressing) 102 is carried on the wound site by the NPWT bandage 5 and applied to the wound simultaneously with the NPWT bandage 5.

[0082] Next, with the NPWT bandage 5 secured to the patient's skin, the removable reinforcement 55 is removed from the atmospheric surface 30 of the membrane 10. See Figure 14.

[0083] At this point, negative pressure can be applied to the wound chamber using the NPWT bandage 5. This is achieved by squeezing the side wall 65 of the pump body 60 between the user's thumb and index finger, compressing the pump body 60 into a substantially fully folded configuration, thereby allowing fluid (e.g., air, liquid, etc.) to exit the inner chamber 70 of the pump body 60 through the atmospheric passage 85 and the atmospheric one-way valve 95. See Figure 15. The fluid in the inner chamber 70 of the pump body 60 is prevented from exiting the inner chamber 70 through the wound passage 80 due to the presence of the wound-side one-way valve 90. Next, the side wall 65 of the pump body 60 is released, and the elastic pump body 60 returns to a substantially fully unfolded configuration, thereby allowing negative pressure to be generated in the inner chamber 70 and the wound-side passage 80, so that the fluid under the wound-side surface 25 of the membrane 10 (e.g., fluid in the wound chamber) is drawn into the inner chamber 70 through the wound passage 80 and the wound-side one-way valve 90. It should be noted that, due to the presence of the one-way valve 95 on the atmospheric side, air in the atmosphere is prevented from entering the inner chamber 70 through the atmospheric passage 85.

[0084] This process of squeezing and releasing the side walls 65 of the pump body 60 is repeated until the pump body 60 of the pump assembly 15 remains in a substantially fully folded configuration (i.e., the side walls 65 of the pump body 60 are bent inward), even when the side walls 65 of the pump body 60 are not being manually compressed. See Figure 16. When the pump body 60 of the pump assembly 15 remains in a substantially fully folded configuration, even when the side walls 65 of the pump body 60 are not being manually compressed, the observer knows that the pressure difference between the fluid pressure in the inner chamber 70 (and wound chamber) and atmospheric pressure exceeds the desired threshold, indicating that the desired negative pressure level has been achieved at the wound site. Note that when the pump body 60 of the pump assembly 15 remains in a substantially fully folded configuration, even when the side walls 65 of the pump body 60 are not being manually compressed, the pump assembly 15 is effectively deactivated, because it is impossible to continue using the pump assembly with the side walls 65 in a substantially fully folded configuration.

[0085] At this point, the atmospheric port 87 of the atmospheric passage 85 can be sealed using the removable cap 100.

[0086] The NPWT bandage 5 is left in place over the wound for an appropriate period (e.g., several days) to protect the wound from contaminants and microorganisms during healing, draw out exudate from the wound, and promote beneficial biological responses at the wound site. When the negative pressure generated in the wound chamber due to leakage drops below a given threshold (which is evident to the observer by the side wall 65 of the pump body 60 returning to a substantially fully deployed configuration), the atmospheric port 87 of the atmospheric passage 85 is unsealed (i.e., by removing the removable cap 100), and the desired negative pressure in the wound chamber can then be re-established using the pump assembly 15 as discussed above (i.e., by repeatedly squeezing and releasing the side wall 65 of the pump body 60).

[0087] The NPWT bandage 5 may be removed from the patient's skin by simply peeling the membrane 10 off the patient's skin, as appropriate.

[0088] Pump body with notches to improve the essentially "binary state" behavior of the pump body As described above, the pump body 60 of the pump assembly 15 is preferably, more specifically, the pump body is (i) A substantially fully unfolded configuration in which the side walls 65 of the pump body 60 and the inner chamber 70 of the pump body 60 have a substantially circular cross-section (see Figure 5) when the pressure difference between the fluid pressure in the inner chamber 70 and atmospheric pressure is less than a given threshold, (ii) The pump body is configured to abruptly change between a substantially fully deployed configuration and a configuration in which the side wall 65 of the pump body 60 is deflected inward (see Figure 6) when the pressure difference between the fluid pressure in the inner chamber 70 and atmospheric pressure exceeds a given threshold.

[0089] Furthermore, as described above, it should be noted that this substantially "binary state" behavior of the pump body 60 is achieved by forming a pump body having a substantially circular cross-section that gives the body "overcenter" deformation characteristics. That is, the side walls of the pump body 60 have a "break" mode in which it abruptly transitions from a substantially fully unfolded configuration to a substantially fully folded configuration, and a "restoration" mode in which it abruptly transitions from a substantially fully folded configuration to a substantially fully unfolded configuration. See Figure 7. As described above, the side walls 65 of the pump body 60 and the pump flange 75 meet at the neck portion 77. (Figure 5) The neck portion 77 has a relatively small width relative to the entire diameter of the pump body 60, and the recess 78 forms the pump assembly 15 such that it extends inward between the membrane 10 and the pump body 60, so that the pump body 60 has a substantially circular cross-section substantially over its entire circumference, and the pump body 60 can freely compress / expand radially with minimal interference from the pump flange 75, allowing the pump body 60 to exhibit substantially "binary" behavior.

[0090] If desired, the pump body 60 can be modified to improve the substantially "binary state" behavior of the pump body.

[0091] As an example, and not an limitation, referring here to Figures 17-20, notches 105 can be formed within the pump body 60 (for example, at the "9 o'clock," "12 o'clock," and "3 o'clock" positions) to further guide the pump body 60 to take only a substantially fully unfolded configuration or a substantially fully folded configuration, thereby improving the substantially "binary state" behavior of the pump body. Note that the more the pump body 60 exhibits true "binary state" behavior, the better the pump efficiency will be, and the better the pump assembly 15 will function as an automatic pressure indicator and automatic pressure limiter.

[0092] Therefore, looking at Figure 20A, the pump body 60 is generally, The configuration is virtually fully deployed before pumping, The folding and unfolding configuration during pumping, A substantially folded configuration "oriented vertically" after a given level of negative pressure is achieved by pumping, A substantially fully deployed configuration after the negative pressure has decayed to below a given level, It can be seen that it possesses.

[0093] Furthermore, the restarted pumping allows for a transition to a substantially fully deployed configuration, after which the desired negative pressure can be re-established.

[0094] NPWT bandages that incorporate gauze (or other absorbent wound dressings) and utilize an improved pump assembly. Next, referring to Figures 21 to 25, another negative pressure wound therapy (NPWT) bandage 5 formed according to the present invention is shown. The NPWT bandage 5 shown in Figures 21 to 25 is substantially the same as the NPWT bandage 5 shown in Figures 1 to 16 and the NPWT bandage 5 shown in Figures 17 to 20, except that (i) in the structure shown in Figures 21 to 25, the membrane 10 comprises multiple layers incorporating gauze (or other absorbent wound dressing), and (ii) in the structure shown in Figures 21 to 25, the pump assembly 15 has a modified structure and is fixed to the membrane 10 using a different method.

[0095] More specifically, in this embodiment of the present invention, the membrane 10 comprises a lower skin-contact polyurethane layer 110 having a central opening 115, an intermediate foam (or gauze or other absorbent wound dressing) layer 120 for placement on the central opening 115 of the lower skin-contact polyurethane layer 110, and a top polyurethane layer 125 for placement on the intermediate foam layer 120 and the lower skin-contact polyurethane layer 110. In a preferred embodiment of the present invention, the top polyurethane layer 125 is formed from a substantially air-impermeable material. And in a preferred embodiment of the present invention, the top polyurethane layer 125 and the lower skin-contact polyurethane layer 110 have the same outer circumference, thereby preventing the top polyurethane layer 125 from contacting the patient's skin. The outer circumferences of the top polyurethane layer 125 and the lower skin-contact polyurethane layer 110 are fixed to each other, with the intermediate foam layer 120 trapped between them. The intermediate foam layer 120 is (i) larger than the periphery of the central opening 115 of the lower skin-contact polyurethane layer 110, and (ii) smaller than the outer periphery of the lower skin-contact polyurethane layer 110 and the upper polyurethane layer 125. In this way, when the NPWT bandage 5 positions the central opening 115 of the lower skin-contact polyurethane layer 110 over the wound, fluid from the wound can pass through the central opening 115 of the lower skin-contact polyurethane layer 110 and reach the intermediate foam layer 120. It will be understood that the adhesive 45 is positioned on the wound-side surface of the lower skin-contact polyurethane layer 110 so that the NPWT bandage 5 can establish a substantially airtight seal around the periphery of the wound (i.e., form the wound chamber described above). An opening 130 is formed in the upper polyurethane layer 125 and overlaps with the central opening 115 of the lower skin-contact polyurethane layer 110, allowing the wound-side passage 80 of the pump assembly 15 to access the fluid (e.g., air, liquid, etc.) in the wound chamber for discharge during pumping of the pump assembly 15 (i.e., via the opening 130 in the upper polyurethane layer 125, the opening in the intermediate foam layer 120, and the central opening 115 in the lower skin-contact polyurethane layer 110).

[0096] The pump assembly 15 used in the NPWT bandage 5 shown in Figures 21 to 25 is generally similar to the pump assembly 15 described above, but differs in that it includes a pair of bases 135A and 135B for attaching the pump assembly 15 to the membrane 10. More specifically, base 135A includes one end of the pump body 60 and is attached to the upper surface of the membrane 10 (i.e., the upper surface of the upper polyurethane layer 125) (for example, by adhesive 137), so that the wound-side passage 80 and the wound-side one-way valve 90 are aligned with the opening 130 in the upper polyurethane layer 125 (thus enabling fluid communication with the wound chamber). Base 135B includes the other end of the pump body 60 and is attached to the upper surface of the membrane 10 (i.e., the upper surface of the upper polyurethane layer 125) (for example, by adhesive 138). The intervening portion 140 of the pump body 60 is lifted onto the upper polyurethane layer 125 of the membrane 10 and suspended and seated between the bases 135A and 135B, thereby forming a space 145 between the intervening portion 140 of the pump body 60 and the upper polyurethane layer 135 of the membrane 10. Since the intervening portion 140 of the pump body 60 is not directly attached to the membrane 10 but is suspended on the membrane 10 by the bases 135A and 135B, the intervening portion 140 of the pump body 60 can be formed with a true circular cross-section, thereby improving the substantially "binary" behavior of the NPWT bandage. It will be understood that the pump body 60 may incorporate one or more of the notches 105 described above to further improve the substantially "binary" behavior of the NPWT bandage.

[0097] NPWT bandage with negative pressure attenuation "warning state" indicator It is also known that, if desired, the pump body 60 can be configured to provide a negative pressure decay "warning state" indicator.

[0098] More specifically, by controlling the number, configuration, and arrangement of the notches 105, the pump body 60 can provide a “warning state” indicator that a negative pressure decay has occurred, but the decay is not sufficient to cause a binary state transition of the pump body (i.e., from a substantially folded configuration to a substantially fully unfolded configuration). By providing a pump body having a number, configuration, and arrangement of notches appropriate to the number, configuration, and arrangement, the pump body can provide a “warning state” indicator (indicating that there is a negative pressure decay below a given level, but it is not sufficient to cause a binary state transition of the pump body from a substantially fully folded state to a substantially fully unfolded state) by causing the pump body to transition from its “vertically oriented” substantially folded configuration (which occurs after a given level of negative pressure has been achieved) to a “horizontally oriented” substantially folded configuration (which occurs after some decay of negative pressure, but not sufficient to cause a binary state transition of the pump body back to a substantially fully unfolded configuration).

[0099] Figures 26 and 27 show exemplary configurations in which a pump body having appropriate notches 105 in number, configuration and arrangement can provide a “warning state” indicator (indicating that there is a negative pressure decay below a given level, but not enough to cause a binary state transition of the pump body to a fully extended state) by transitioning the pump body from a “vertically oriented” substantially folded configuration (which occurs after a given level of negative pressure is achieved) to a “horizontally oriented” substantially folded configuration (which occurs after some decay of negative pressure, but not enough to cause a binary state transition of the pump body to a fully extended state).

[0100] Therefore, in this embodiment of the present invention, looking at Figure 28, the pump body 60 is generally, The configuration is virtually fully deployed before pumping, The folding and unfolding configuration during pumping, A substantially folded configuration "oriented vertically" after a given level of negative pressure is achieved by pumping, A "horizontally oriented" substantially folded configuration when a given level of negative pressure has been achieved, but there is some decay of the negative pressure, but not enough to cause a binary state transition of the pump body to a fully unfolded state, A substantially fully deployed configuration after the negative pressure has decayed to below a given level, It can be seen that it possesses.

[0101] Furthermore, the restarted pumping allows for a transition to a substantially fully deployed configuration, after which the desired negative pressure can be re-established.

[0102] NPWT bandage with canister for collecting exudate In some situations, wounds may produce a large amount of exudate. In these situations, it may be desirable to use a negative pressure wound therapy (NPWT) dressing that includes a canister to collect the exudate.

[0103] For example, Figure 29 shows a negative pressure wound therapy (NPWT) bandage 5 including a canister 200 for collecting exudate. In this embodiment of the present invention, a one-way valve 95 on the atmospheric side of a pump assembly 15 outputs to the interior 205 of the canister 200 so that exudate 210 collects inside the canister 200. In one embodiment of the present invention, the canister 200 includes an opening covered by a membrane 215, the membrane 215 being gas-permeable but fluid-impermeable so that gas can escape from the canister 200 but liquid is trapped inside.

[0104] In another embodiment of the present invention, as shown here in Figure 30, the canister 200 can be positioned between the wound chamber and the wound-side one-way valve 90 of the pump assembly 15. More specifically, in this embodiment of the present invention, the interior 205 of the canister 200 is in fluid communication with the wound chamber and the wound-side one-way valve 90 of the pump assembly 15, so that pumping of the pump assembly 15 generates negative pressure within the canister 200, and thus within the wound chamber. Preferably, the canister 200 includes the aforementioned membrane 215 (gas-permeable but liquid-impermeable) adjacent to the wound-side one-way valve 90 of the pump assembly 15, so that gas can escape from the canister 200, but liquid is trapped inside the canister 200 and not pass into the pump assembly 15.

[0105] In yet another embodiment of the present invention, as seen in Figure 31, the canister 200 is positioned between the wound chamber and the wound-side one-way valve 90 of the pump assembly 15 in a manner similar to the structure in Figure 30, but differs in that the pump assembly 15 is mounted on top of the canister 200.

[0106] The canister 200 may be integrally formed with the pump body 60, or it may be formed separately from the pump body 60 and simply fluid-connected to the pump body 60. In either case, it should be understood that the canister 200 is preferably attached to a portion of the negative pressure wound therapy (NPWT) bandage 5 so that the canister 200 moves in conjunction with the rest of the bandage.

[0107] Furthermore, if desired, the canister 200 may contain an absorbent or superabsorbent material (or have one or more of its inner surfaces coated therewith) for absorbing fluid exudate discharged from the wound chamber. For example, but not limited to, the canister 200 may contain an absorbent or superabsorbent crystal or hydrophilic colloid or gel-forming material (or have one or more of its inner surfaces coated therewith).

[0108] The canister 200 can be used with any of the pump assemblies disclosed herein. For example, but not limited to, the canister 200 can be used with the pump assemblies 15 shown in Figures 1 to 4, 17 to 20A, 21 to 25, 26 to 28, and the like.

[0109] NPWT bandage with Luer lock for suction attachment In some situations, it may be desirable to fabricate a larger negative pressure wound therapy (NPWT) bandage 5 to cover a larger wound chamber. This can be achieved by increasing the size of the membrane (or sheet) 10. However, increasing the size of the pump assembly 15 may not be desirable because it is usually desirable for the pump assembly to maintain a non-invasive low profile. Increasing the size of the membrane (or sheet) 10 while maintaining the size of the pump assembly 15 may be clinically undesirable because it may require even greater pump compression to evacuate a large wound chamber to the correct negative pressure level. In other words, increasing the size of the membrane (or sheet) 10 while maintaining the size of the pump assembly 15 has the effect of increasing the number of pump compressions required to establish the correct negative pressure level in the wound chamber. For this reason, clinical considerations of the size of the pump assembly and the number of pump compressions used to establish the correct negative pressure level in the wound chamber may, in a practical sense, limit the size of the membrane (or sheet) 10.

[0110] To address this, the negative pressure wound therapy (NPWT) bandage 5 can be configured to connect to a suction source, thereby allowing the suction source to be applied to the NPWT bandage 5 to establish the correct negative pressure level within the wound chamber without requiring compression of the pump body 60. As an example rather than an limitation, looking here at Figure 32, the NPWT bandage 5 may include half of the Luer lock 300, and the suction line 305 may include the second half of the Luer lock 310, thereby allowing the suction line 305 to be fluidly connected to the atmospheric port 87 of the pump body 60. When the other end 315 of the suction line 305 is connected to a functioning suction source 320, the suction source 320 can apply suction to the pump body 60. This suction is then automatically applied to the wound chamber, thereby allowing the suction source 320 to establish negative pressure within the wound chamber.

[0111] Importantly, when the correct level of negative pressure is established within the wound chamber, the walls of the pump body 60 fold in the manner described above. Therefore, even when the suction source 320 is used to generate negative pressure within the wound chamber, the NPWT bandage 5 still serves as a visual indicator when the appropriate level of negative pressure is established within the wound chamber. This is because the pump assembly 15 transitions from its substantially fully unfolded configuration to its substantially fully folded configuration when the appropriate level of negative pressure is established within the wound chamber.

[0112] After an appropriate level of negative pressure is established within the wound chamber using the suction source 320, the suction line 305 can then be removed from the NPWT bandage 5.

[0113] Subsequently, if the negative pressure level in the wound chamber decreases, the correct negative pressure level in the wound chamber can be re-established by compressing the pump body 60 using the pump assembly 15, or by reconnecting the NPWT bandage 5 to the suction source 320.

[0114] In the preferred embodiment of the present invention discussed above, the NPWT bandage 5 includes half of the Luer lock, and the suction line 305 includes a second half of the Luer lock. However, the present invention is not limited to the use of Luer lock connections, and the suction line 305 can be connected to the pump assembly 15 using other types of fluid connectors.

[0115] As discussed above, the NPWT bandage 5 serves as a visual indicator when an appropriate level is established within the wound chamber, i.e., by transitioning from its substantially fully unfolded configuration to its substantially fully folded configuration.

[0116] Importantly, according to another feature of the present invention, by modifying the configuration of the notches 105 of the pump body 60, the NPWT bandage 5 can also function as a pressure limiter, preventing the suction source 320 from establishing an excessively high level of negative pressure in the wound chamber. This is done by forming each of the notches as two interlocked notches 105A, 105B, with a full-thickness sidewall portion 65C positioned between the two interlocked notches 105A, 105B. See Figure 33. As a result of this construction, the correct level of negative pressure is established in the wound chamber, thereby when the pump body 60 transitions from its substantially fully unfolded configuration to its substantially fully folded configuration, the directly opposite full-thickness sidewall portions 65C of the pump body 60 move radially inward and engage with each other, thereby sealing the inner chamber 70 of the pump body 60. See Figure 34. This prevents the suction source 320 from igniting any further suction into the wound chamber. In this way, the NPWT bandage 5 also functions as a pressure limiter, preventing the suction source 320 from establishing an excessively high level of negative pressure in the wound chamber.

[0117] The Luer lock 300 can be used with any of the pump assemblies disclosed herein. For example, but not limited to, the Luer lock 300 can be used with the pump assemblies 15 shown in Figures 1 to 4, 17 to 20A, 21 to 25, 26 to 28, 29 to 31, and the like.

[0118] NPWT bandage, in which the wound chamber includes a lateral extension, the pump assembly is in fluid communication with the lateral extension, and the pump assembly is offset laterally from the wound while maintaining fluid communication with the wound. In some situations, it may be desirable to offset the pump assembly laterally from the wound while maintaining fluid communication with the wound. More specifically, difficult anatomical areas with more complex shapes present challenges for negative pressure wound therapy (NPWT) bandages with a pump assembly placed directly over the wound being treated. By preparing an NPWT bandage in which the wound chamber includes a lateral extension and the pump assembly is in fluid communication with the lateral extension, the pump assembly can be offset laterally from the wound while maintaining fluid communication with the wound.

[0119] As an example, and not an limitation, in a structure where an NPWT bandage is used to treat a wound in the groin area, the NPWT bandage can be positioned on the patient's biostructure so that the main portion of the wound chamber overlaps the wound and the lateral extension of the wound chamber extends along the curve of the thigh, thereby positioning the pump assembly at the top of the upper thigh, which is an anatomical region for supporting the pump assembly that is more stable and less complex in terms of tissue distribution.

[0120] As a further example, and not an exhaustive one, in a configuration where an NPWT bandage is used to treat a wound on a patient's back, the NPWT bandage can be positioned on the patient's biological structure so that the main portion of the wound chamber overlaps the wound on the patient's back, and the lateral extension of the wound chamber extends along the curve of the patient's torso, thereby allowing the pump assembly to be positioned on the front of the patient, where the patient can easily access the pump assembly.

[0121] NPWT bandages can be provided with a wide variety of wound chamber configurations and pump arrangements as appropriate for different applications.

[0122] Figures 35 to 38 show a negative pressure wound therapy (NPWT) bandage 5 in which the wound chamber includes a lateral extension, and the pump assembly is in fluid communication with the lateral extension, thereby allowing the pump assembly to be offset laterally from the wound while maintaining fluid communication with the wound.

[0123] More specifically, the NPWT bandage 5 shown in Figures 35-38 includes a membrane 10 and a pump assembly 15. The membrane 10 includes a first portion 405 for placement over the wound and a second portion 410 for extending laterally away from the wound and supporting the pump assembly 15 at an anatomical position spaced apart from the wound.

[0124] In this embodiment of the present invention, the membrane 10 is generally similar to the membrane 10 with the structure shown in Figures 21 to 34, comprising a lower skin-contact polyurethane layer 110, an intermediate foam layer 120 for placement on the lower skin-contact polyurethane layer 110, and a top polyurethane layer 125 for placement on the intermediate foam layer 120 and the lower skin-contact polyurethane layer 110. In a preferred embodiment of the present invention, the top polyurethane layer 125 is formed from a substantially air-impermeable material. The outer peripheries of the top polyurethane layer 125 and the lower skin-contact polyurethane layer 110 are fixed to each other, with the intermediate foam layer 120 trapped between them.

[0125] However, in this structure (i.e., the structure shown in Figures 35 to 38), a central opening 115 is formed in the first portion 405 of the lower skin-contact polyurethane layer 110 of the membrane 10, and an opening 130 is formed in the second portion 410 of the upper polyurethane layer 125 of the membrane 10. The intermediate foam layer 120 is in fluid communication with the central opening 115 of the first portion 405 and the opening 130 of the second portion 410. In this way, when the NPWT bandage 5 is adhered to a biological structure with its central opening 115 positioned over the wound, the membrane 10 forms a wound chamber largely defined by the configuration of the intermediate foam layer 120. This wound chamber generally comprises (i) a main portion that overlaps the central opening 115 of the first portion 405, and (ii) a lateral extension that extends from the main portion of the wound chamber to the pump assembly 15.

[0126] The pump assembly 15 is mounted on the upper polyurethane layer 125, and the wound-side passage 80 of the pump assembly 15 accesses the fluid (e.g., air, liquid, etc.) in the lateral extension of the wound chamber, thereby accessing the fluid in the main part of the wound chamber (i.e., through the porous cells of the intermediate foam layer 120), and thereby allowing the fluid to be drawn away from the wound site.

[0127] In the exemplary use of the NPWT bandage 5 shown in Figures 35-38, the NPWT bandage is positioned over the patient's biostructure so that the main portion of the wound chamber overlaps the wound, and the lateral extension of the wound chamber extends along the patient's biostructure so that the pump assembly can be positioned in another location that is laterally offset from the wound, for example, more stable and / or less tissue-distributively complex and / or more easily accessible to the patient. Next, negative pressure can be applied to the wound chamber using the NPWT bandage 5 so that a fluid (e.g., air, liquid, etc.) can pass from the wound through the central opening 115 into the main portion of the wound chamber, through the lateral extension of the wound chamber (e.g., through the porous cells of the intermediate foam layer 120), and into the pump assembly 15 through the opening 130 in the second portion 410 of the upper polyurethane layer 125 of the membrane 10.

[0128] The NPWT bandage 5 shown in Figures 35-38 can also be used in other complex or mobile wound locations, including, but not limited to, the feet (e.g., diabetic foot ulcers), joints such as the ankles, knees, shoulders, or hips (e.g., after joint surgery, ligament repair, arthroscopic procedures, or joint replacement), arms (forearms or upper arms), neck, head, spine, or back (the pump assembly 15 may be positioned on the front of the body while the main portion of the wound chamber is positioned over the wound). In each of these wound locations and others, the anatomical location of the wound may present challenges to wound dressings with integrated pinch-pump assemblies due to the composition of the biostructure, the mobility of the anatomical location, the radius of curvature in the anatomical location, or the location of the wound (which may not be easily visible or manually accessible to the patient). Importantly, the NPWT bandage formed according to the present invention includes a wound chamber with a lateral extension, and the pump assembly is in fluid communication with this lateral extension, thereby offsetting the pump assembly laterally from the wound while maintaining fluid communication with the wound. This provides the ability to position the pinch pump assembly in an easily accessible and physically stable anatomical location while still maintaining air / fluid communication with the wound.

[0129] This new NPWT bandage is not limited, 1. A wound chamber having lateral extensions of various lengths (e.g., short, long, etc.), wherein the lateral extensions coincide with the center of the dressing, and the pinch pump assembly is oriented at any angle with respect to the center line of the dressing, and the wound chamber and 2. A wound chamber having lateral extensions of various lengths (e.g., short, long, etc.), wherein the lateral extensions are positioned away from the centerline of the dressing, It can include any number of shapes, including those mentioned above.

[0130] As an example, rather than an limitation, Figures 39–42 show alternative structures for negative pressure wound therapy (NPWT) bandages 5, where the lateral extension of the wound chamber has a different length than that shown in Figures 35–38.

[0131] As a further example, rather than an exhaustive one, Figures 43–46 show an alternative structure for negative pressure wound therapy (NPWT) bandage 5, where the pinch pump assembly extends across the axis of the lateral extension of the wound chamber.

[0132] As a further example, and not an limitation, as we see in Figure 46A, the second portion 410 of the wound chamber can extend parallel to, but offset from, the first portion 405 of the wound chamber (as opposed to being positioned adjacent to one end of the first portion 405 of the wound chamber, as shown in the structures of Figures 35-38, 39-42, and 43-46). The pump assembly 15 is mounted on the second portion 410 to fluidize the wound chamber (as described for the structures of Figures 35-38, 39-42, and 43-46), but in the structure shown in Figure 46A, the pump assembly 15 extends substantially parallel to the first portion 405 of the wound chamber. Note that in the structure of Figure 46A, the footprint of the negative pressure wound therapy (NPWT) bandage 5 can be a "square" (meaning the length and width of the bandage are more equal) rather than a "long rectangle" (meaning the length of the bandage is substantially greater than the width of the bandage), as shown in the structures of Figures 35-38, 39-42, and 43-46.

[0133] If desired, the notches 105 formed in the pump body 60 of the pump assemblies shown in Figures 17 to 20, and / or the notches 105 formed in the pump body 60 of the pump assemblies shown in Figures 26 to 28, can also be formed within the respective pump bodies of the NPWT bandages 5 shown in Figures 35 to 38, 39 to 42, and 43 to 46. Furthermore, if desired, the canister 200 can be used with the pump assemblies of the NPWT bandages 5 shown in Figures 35 to 38, 39 to 42, and 43 to 46. And, if desired, the Luer lock 300 can be used with the pump assemblies of the NPWT bandages 5 shown in Figures 35 to 38, 39 to 42, and 43 to 46.

[0134] Negative pressure wound therapy (NPWT) bandage for covering wounds, comprising a permeable top layer that traps a layer of foam over the wound, the foam layer having a series of windows that (i) allow direct visualization of the wound and (ii) provide a metric along the length of the bandage to indicate whether the bandage needs to be changed, and further comprising a foam layer that also includes periphery serrations to allow the bandage to conform to curved wounds. The above description discloses a wide range of negative pressure wound therapy (NPWT) bandages that cover a wound and apply negative pressure to the wound to help prevent infection at the wound. The NPWT bandages disclosed in the above description generally comprise (i) a membrane 10 for placement over a wound, and (ii) an implemented pump assembly 15 for applying and maintaining negative pressure at the wound site.

[0135] As shown in the structure in Figures 21 to 46, the membrane 10 generally comprises (i) a lower skin-contact polyurethane layer 110 having an opening 115 for placement over a wound, (ii) an intermediate foam layer 120 for placement over the opening 115 in the lower skin-contact polyurethane layer 110 and for contact with the wound, and (iii) an upper polyurethane layer 125 for placement over the intermediate foam layer 120 and the lower skin-contact polyurethane layer 110, the outer periphery of the upper polyurethane layer 125 and the lower skin-contact polyurethane layer 110 being fixed to each other, with the intermediate foam layer 120 trapped between them, and furthermore, the lower skin-contact polyurethane layer 110 is provided with an adhesive for adhering the membrane 10 to the patient's skin.

[0136] The pump assembly 15 can be centered over the wound (see the pump assembly 15 shown in the embodiments of Figures 1 to 25) or it can be offset laterally from the wound (see the pump assembly 15 shown in the embodiments of Figures 35 to 46).

[0137] In particular, considering the negative pressure applied to the wound, exudate is released from the wound site at a high frequency. In many cases, it may be desirable to obtain indication of the amount of exudate produced by the wound, because a large amount of exudate may necessitate more frequent bandaging changes (for example, the bandage may become saturated with exudate, or the exudate may reach the pump, which reduces the pump's function and / or may cause the exudate to be expelled from the pump).

[0138] For this purpose, a novel bandage is provided here for use with wounds of a type likely to release exudate. More specifically, Figures 47, 48, and 49 show a bandage 500 for placement over wounds likely to release exudate. Bandage 500 is similar to the NPWT bandage disclosed in the above description, except that the upper polyurethane layer 125 of the membrane 10 is replaced by the upper layer 505, and the intermediate foam layer 120 of the membrane 10 is replaced by the foam layer 510.

[0139] More specifically, the top layer 505 of the bandage 500 is formed from a permeable material (e.g., a film). The permeable top layer 505 of the bandage allows an observer to see through the top layer of the bandage and observe the foam layer 510 (which absorbs exudate) covering the wound.

[0140] The foam layer 510 (see Figures 47-55) is provided with a series of windows 515 extending through the foam layer. The windows 515 allow for direct visualization of the wound, provide a metric along the length of the bandage, and indicate whether the bandage needs to be changed. Note that in Figures 50 and 53-55, only the foam layer 510 of the bandage 500 is shown for simplicity of explanation.

[0141] More specifically, as can be seen in Figures 51 and 52, the visualization of the foam layer 510 through the permeable upper layer 505 allows the observer to visualize whether a large amount of exudate has moved from the wound into the foam layer (exudate is generally yellowish, easily distinguishable from the base color of the foam, which is preferably white, light gray, etc.), and the windows 515 provide a metric that extends along the length of the bandage (for example, each window is a "marker line" along the "ruler" of the bandage). The amount of exudate released by the wound is reflected by the amount of foam indicating the presence of the exudate (this can be quantified by looking at the portion of the foam layer 510 showing the exudate and counting the number of windows adjacent to the area of ​​the foam layer 510 showing the exudate). When the number of windows adjacent to the area of ​​the foam layer 510 showing the exudate reaches a certain number along the length of the foam layer 510, the observer can sense the amount of exudate coming out of the wound and decide whether or not to change the bandage. As an example, and not an limitation, when the saturation level of the foam layer 510 is less than 50% (as shown in Figure 51, this means that three out of seven windows are adjacent to the area of ​​the foam layer 510 showing exudate 518), the bandage can remain on the wound. However, if the saturation level of the foam layer 510 exceeds 50% (as shown in Figure 52, this means that four or more windows are adjacent to the area of ​​the foam layer 510 showing exudate 518), the bandage can be changed. As a further example, and not an limitation, when the area of ​​the foam layer 510 surrounding the window closest to the pump shows the presence of exudate, a decision can be made to change the bandage to prevent the exudate from reaching the pump.

[0142] In a preferred embodiment, the bandage 500 may be provided with markings 520 along the length of the bandage. The markings 520 may be formed on a permeable upper layer 505 and / or foam layer 510 (see Figures 50 to 55). As shown in Figures 53 and 54, the markings 520 can be used in combination with a window 515 in the foam layer 510 to allow a healthcare professional to align the bandage 500 along the wound line 525 when applying the bandage to a wound.

[0143] If desired, the outer periphery of the foam layer 510 may be formed with a wavy edge or periphery serrations 530 (see Figures 47-55). As shown in Figure 55, the wavy edge or periphery serrations 530 allow the bandage 500 to curve somewhat when applied to the skin surface, enabling the bandage 500 to be positioned over a non-linear cut. For this reason, it is important to note that the portion of the bandage 500 positioned over the wound should not be excessively curved, because excessive curvature of the bandage can cause wrinkles, which may result in a failure of sealing around the wound chamber. The range of curvature of the bandage that can be accepted without interfering with the function of the bandage is not limited but depends on several factors, including the size and shape (width and depth) of the periphery serrations 530 in the foam layer 510, the ability of the upper layer 505 to deform, and the ability of the lower skin-contact polyurethane layer 110 to deform. If desired, serrations on the outer periphery can be formed within the upper layer 505 and / or the lower skin-contact polyurethane layer 110 to increase the degree of curvature that the bandage can accept (for example, to reduce “wrinkling” of the upper layer 505 and the lower skin-contact polyurethane layer 110 when the bandage is positioned over a non-linear cut, and to increase the degree of curvature that the bandage can accept without compromising the airtight seal made between the bandage and the skin).

[0144] In one embodiment of the present invention, as shown in Figures 47, 48, and 49, the bandage 500 is preferably a negative pressure wound therapy (NPWT) bandage having an implemented pump assembly 15, the pump assembly 15 being laterally offset from the bandage 500 in this configuration, and this configuration is substantially the same as the NPWT bandages shown in Figures 35 to 37. However, if desired, the permeable upper layer 505, window 515, marking 520, and outer periphery serrations 530 described above may be provided with other NPWT bandages having a laterally offset pump assembly, such as the NPWT bandages shown in Figures 39 to 42, and / or the NPWT bandages shown in Figures 43 to 46.

[0145] In another embodiment of the present invention, as shown in Figures 56 and 57, the bandage 500 is a negative pressure wound therapy (NPWT) bandage having an implemented pump assembly 15, the pump assembly 15 being positioned on a portion of the upper layer 505 and on the foam layer 510.

[0146] In yet another embodiment of the present invention, the bandage 500 is configured to be connected to a pump located away from the bandage, or to another suction source (e.g., wall suction).

[0147] The novel bandage can also be used without applying negative pressure to the wound. For example, and not limited to, as shown in Figures 58 and 59, the bandage 500 can omit an implemented pump and eliminate the need for a remotely located pump or connection to another suction source (e.g., wall suction). In this embodiment of the invention, the bandage 500 can essentially be used as a general-purpose bandage.

[0148] In other embodiments of the present invention, the lower skin-contact polyurethane layer 110 of the bandage 500 may be omitted, and the upper layer 505 may be provided with (i) an adhesive for attaching the foam layer 510 to the upper layer 505, and (ii) an adhesive for adhering the upper layer 505 to the patient's skin. Not limited to, but as examples, the structures in Figures 47 to 55 may omit the lower skin-contact polyurethane layer 110 of the bandage 500, or the structures in Figures 56 and 57 may omit the lower skin-contact polyurethane layer 110 of the bandage 500, or Figures 58, 59 and 60 may omit the lower skin-contact polyurethane layer 110 of the bandage 500.

[0149] Furthermore, the lower skin-contact polyurethane layer 110 can be omitted from any of the NPWT bandages shown in Figures 21 to 46, and it should be noted that the upper polyurethane layer 125 is provided with (i) an adhesive for attaching the intermediate foam layer 120 to the upper polyurethane layer 125, and (ii) an adhesive for adhering the upper polyurethane layer 125 to the patient's skin.

[0150] If desired, the notches 105 formed in the pump body 60 of the pump assemblies shown in Figures 17 to 20, and / or the notches 105 formed in the pump body 60 of the pump assemblies shown in Figures 26 to 28, may also be formed within the respective pump bodies of the bandages 500 shown in Figures 47 to 49, and Figures 56 and 57. Furthermore, if desired, the canister 200 can be used with the pump assemblies of the bandages 500 shown in Figures 47 to 49, and Figures 56 and 57. And, if desired, the Luer lock 300 can be used with the pump assemblies of the bandages 500 shown in Figures 47 to 49, and Figures 56 and 57.

[0151] Modification of a Preferred Embodiment It should be understood that many additional modifications in details, materials, steps, and component arrangements, as described and illustrated herein for the purpose of illustrating the essence of the present invention, can be made by those skilled in the art, and still remain within the principles and scope of the present invention. (1) A first aspect of the present invention is a negative pressure wound therapy (NPWT) bandage for applying negative pressure to a wound, the NPWT bandage being a membrane configured to be placed over a wound, such that a wound chamber is formed between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending through the membrane from the wound-side surface to the atmospheric-side surface, and a pump assembly supported by the membrane, the pump assembly comprising a pump body having a wall structure arranged around the pump chamber, at least a portion of the wall structure being elastic, and further comprising a pump body communicating with the wound chamber through the opening formed in the membrane, and an atmospheric-side passage extending through the wall structure and fluidizing the pump chamber to the atmosphere, wherein when a compressive force is applied to the wall structure of the pump body, the fluid in the pump chamber is pushed out of the pump chamber through the atmospheric-side passage, and the pump body The pump assembly comprises a pump assembly such that when the compressive force applied to the wall structure is subsequently reduced, the fluid in the wound chamber is drawn into the pump chamber through the opening formed in the membrane, wherein when the pressure difference between the pressure of the fluid in the pump chamber and atmospheric pressure is below a predetermined threshold, the pump body takes a substantially fully deployed configuration to indicate that the negative pressure in the wound chamber is below the predetermined threshold; when the pressure difference between the pressure of the fluid in the pump chamber and atmospheric pressure is above the predetermined threshold, the pump body takes a substantially fully folded configuration to indicate that the negative pressure in the wound chamber is above the predetermined threshold; and further, the pump body is configured to provide a visual indicator that the negative pressure in the wound chamber is decreasing but has not decreased enough to fall below the predetermined threshold and cause the pump body to convert to its substantially fully deployed configuration. (2) According to a second aspect of the present invention, in the first aspect, the predetermined threshold is approximately 60 mmHg to approximately 180 mmHg. (3) According to a third aspect of the present invention, in the first embodiment, the pump body includes a substantially cylindrical configuration. (4) According to a fourth aspect of the present invention, in the third aspect, when the pump body is in a substantially fully deployed configuration, the pump body and the pump chamber include a substantially circular cross-section. (5) According to a fifth aspect of the present invention, in the third aspect, when the pump body is in its substantially completely folded configuration, the side walls of the wall structure of the pump body are deflected inward. (6) According to a sixth aspect of the present invention, in the fifth aspect, when the pump body is in a substantially completely folded state, the side walls of the wall structure of the pump body are in contact with each other. (7) According to a seventh aspect of the present invention, in the fifth aspect, at least two notches are formed in the wall structure of the pump body. (8) According to the eighth aspect of the present invention, in the seventh aspect, when the negative pressure in the wound chamber is decreasing but not decreasing enough to fall below a predetermined threshold to convert the pump body into its substantially fully deployed configuration, the upper and bottom walls of the wall structure of the pump body flex inward. (9) According to a ninth aspect of the present invention, in the first embodiment, the pump assembly is mounted on the membrane by a pair of bases. (10) According to a tenth aspect of the present invention, in the ninth aspect, the pump body is suspended between the pair of bases and spaced apart from the membrane. (11) According to an eleventh aspect of the present invention, in a first aspect, the pump body has a substantially circular cross-section, the pump body is mounted on the membrane by a pair of bases joined to the pump body at the "6 o'clock position", the pump body is suspended between the pair of bases and separated from the membrane, and notches are formed in the wall structure of the pump body at the "9 o'clock position" and the "3 o'clock position", and when the pump body is in its substantially fully folded configuration, the side walls of the wall structure of the pump body bend inward at the "9 o'clock position" and the "3 o'clock position", and when the negative pressure in the wound chamber is decreasing but has not decreased enough to fall below a predetermined threshold to convert the pump body to its substantially fully unfolded configuration, the top and bottom walls of the wall structure of the pump body bend inward at the "12 o'clock position" and the "6 o'clock position". (12) A twelfth aspect of the present invention is a method for applying negative pressure to a wound, the step of preparing a negative pressure wound therapy (NPWT) bandage, the NPWT bandage being a membrane configured to be placed over a wound, such that a wound chamber is formed between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending through the membrane from the wound-side surface to the atmospheric-side surface, and a pump assembly supported by the membrane, the pump assembly comprising a pump body having a wall structure arranged around the pump chamber. The wall structure is elastic, and the pump chamber comprises a pump body communicating with the wound chamber through the opening formed in the membrane, and an atmospheric passage extending through the wall structure and providing a fluid connection between the pump chamber and the atmosphere, wherein when a compressive force is applied to the wall structure of the pump body, the fluid in the pump chamber is pushed out of the pump chamber through the atmospheric passage, and when the compressive force applied to the wall structure of the pump body is subsequently reduced, the fluid in the wound chamber is formed in the membrane A pump assembly comprising: a step of drawing the NPWT bandage into the pump chamber through the opening, and when the pressure difference between the fluid pressure in the pump chamber and atmospheric pressure is below a predetermined threshold, the pump body takes a substantially fully deployed configuration, thereby indicating that the negative pressure in the wound chamber is below the predetermined threshold; when the pressure difference between the fluid pressure in the pump chamber and atmospheric pressure is above the predetermined threshold, the pump body takes a substantially fully folded configuration, thereby indicating that the negative pressure in the wound chamber is above the predetermined threshold; and further, the pump body is configured to provide a visual indicator that the negative pressure in the wound chamber is decreasing but has not decreased enough to fall below the predetermined threshold and cause the pump body to convert to its substantially fully deployed configuration; a step of positioning the NPWT bandage over the wound and forming the wound chamber between the membrane and the wound; and a step of applying a compressive force to the wall structure of the pump body, and then reducing the compressive force applied to the wall structure of the pump body.The procedure includes the step of applying negative pressure to the wound. (13) According to a thirteenth aspect of the present invention, in a twelfth aspect, the compressive force applied to the wall structure of the pump body and then the compressive force applied to the wall structure of the pump body is repeated until the pressure difference between the fluid pressure in the pump chamber and atmospheric pressure exceeds a predetermined threshold, and the pump body is thus in a substantially completely folded configuration. (14) According to a fourteenth aspect of the present invention, in a twelfth aspect, when the pressure difference between the pressure of the fluid in the pump chamber and atmospheric pressure is less than a predetermined threshold, and the pump body is thus in a substantially fully unfolded configuration, a compressive force is applied to the wall structure of the pump body, and then the compressive force applied to the wall structure of the pump body is reduced, and this is repeated until the pressure difference between the pressure of the fluid in the pump chamber and atmospheric pressure exceeds the predetermined threshold, and the pump body is thus in a substantially fully folded configuration. (15) According to a 15th aspect of the present invention, in a 12th aspect, the pump body provides a visual indicator that the negative pressure in the wound chamber is decreasing but has not decreased enough to fall below a predetermined threshold and convert the pump body to its substantially fully unfolded configuration, and then the compressive force applied to the wall structure of the pump body is reduced, and this is repeated until the pressure difference between the fluid pressure in the pump chamber and atmospheric pressure exceeds the predetermined threshold and the pump body is thus substantially fully folded. (16) According to the sixteenth aspect of the present invention, in the twelfth aspect, the predetermined threshold is about 60 mmHg to about 180 mmHg. (17) According to the seventeenth aspect of the present invention, in the twelfth aspect, the pump body includes a substantially cylindrical configuration. (18) According to the eighteenth aspect of the present invention, in the seventeenth aspect, when the pump body is in a substantially fully deployed configuration, the pump body and the pump chamber include a substantially circular cross-section. (19) According to a 19th aspect of the present invention, in the 17th aspect, when the pump body is in its substantially completely folded configuration, the side walls of the wall structure of the pump body are deflected inward. (20) According to a 20th aspect of the present invention, in the 19th aspect, when the pump body is in a substantially completely folded configuration, the side walls of the wall structure of the pump body are in contact with each other. (21) According to the 21st aspect of the present invention, in the 19th aspect, at least two notches are formed in the wall structure of the pump body. (22) According to the 22nd aspect of the present invention, in the 21st aspect, when the negative pressure in the wound chamber is decreasing but not decreasing enough to fall below a predetermined threshold to convert the pump body into its substantially fully deployed configuration, the upper and bottom walls of the wall structure of the pump body flex inward. (23) According to the 23rd aspect of the present invention, in the 12th aspect, the pump assembly is mounted on the membrane by a pair of bases. (24) According to a 24th aspect of the present invention, in a 23rd aspect, the pump body is suspended between the pair of bases and spaced apart from the membrane. (25) According to a 25th aspect of the present invention, in a 12th aspect, the pump body has a substantially circular cross-section, the pump body is mounted on the membrane by a pair of bases joined to the pump body at the "6 o'clock position", the pump body is suspended between the pair of bases and separated from the membrane, and notches are formed in the wall structure of the pump body at the "9 o'clock position" and the "3 o'clock position", and when the pump body is in its substantially fully folded configuration, the side walls of the wall structure of the pump body flex inward at the "9 o'clock position" and the "3 o'clock position", and when the negative pressure in the wound chamber is decreasing but has not decreased enough to fall below a predetermined threshold to convert the pump body to its substantially fully unfolded configuration, the top and bottom walls of the wall structure of the pump body flex inward at the "12 o'clock position" and the "6 o'clock position". (26) A 26th aspect of the present invention is a negative pressure wound therapy (NPWT) bandage for applying negative pressure to a wound, the NPWT bandage comprising a membrane configured to be placed over a wound, such that a wound chamber is formed between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending through the membrane from the wound-side surface to the atmospheric-side surface, and a pump assembly supported by the membrane, the pump assembly comprising a pump body comprising a wall structure arranged around the pump chamber, the wall structure comprising at least a portion of which is elastic, and the wall structure A pump assembly comprising a wound-side passage extending through and communicating with the wound chamber, and an atmospheric-side passage extending through the wall structure and connecting the pump chamber to the atmosphere; and a canister configured to fluidly communicate with the wound chamber and the pump assembly, the canister comprising an internal chamber for collecting exudate exiting the wound chamber, wherein the pump assembly is configured to generate negative air pressure within the wound chamber so that exudate from the wound chamber flows out of the wound chamber into the internal chamber of the canister. (27) According to a 27th aspect of the present invention, in a 26th aspect, the pump assembly and the canister are mounted on the membrane such that exudate exits the wound chamber, passes through the wound-side passage of the pump assembly, enters the pump chamber, passes through the air-side passage of the pump assembly, and flows into the internal chamber of the canister. (28) According to a 28th aspect of the present invention, in a 27th aspect, the pump assembly further comprises an atmospheric one-way valve located in the atmospheric passage of the pump assembly, the atmospheric one-way valve being configured to allow seepage to flow from the pump chamber through the atmospheric passage into the internal chamber of the canister, but to prevent seepage from flowing from the internal chamber of the canister through the atmospheric passage into the pump chamber. (29) According to a 29th aspect of the present invention, in a 26th aspect, the pump assembly and the canister are mounted on the membrane such that the exudate flows out of the wound chamber and directly into the internal chamber of the canister. (30) According to a 30th aspect of the present invention, in a 29th aspect, the pump assembly further comprises a wound-side one-way valve located in the wound-side passage of the pump assembly, the wound-side one-way valve being configured to allow fluid to flow from the internal chamber of the canister through the wound-side passage to the pump chamber, but to prevent fluid from flowing from the pump chamber through the wound-side passage to the internal chamber of the canister. (31) According to the 31st aspect of the present invention, in the 26th aspect, the canister and the pump assembly are mounted on the atmospheric surface of the membrane. (32) According to a 32nd aspect of the present invention, in a 26th aspect, the canister is mounted on the atmospheric surface of the membrane, and the pump assembly is mounted on the canister such that the canister is positioned between the atmospheric surface of the membrane and the pump assembly. (33) According to the 33rd aspect of the present invention, in the 26th aspect, the canister further includes an atmospheric opening. (34) According to a 34th aspect of the present invention, in a 33rd aspect, the atmospheric opening includes a gas permeable membrane, the gas permeable membrane allowing a gas to pass through the membrane. (35) According to the 35th aspect of the present invention, in the 34th aspect, the gas permeable membrane prevents the liquid from passing through the gas permeable membrane. (36) According to the 36th aspect of the present invention, in the 26th aspect, the canister is integrally formed with the pump body. (37) According to the 37th aspect of the present invention, in the 26th aspect, the canister is formed separately from the pump body. (38) According to the 38th aspect of the present invention, in the 26th aspect, the internal chamber of the canister further comprises an absorbent material for absorbing the liquid present in the internal chamber of the canister. (39) According to the 39th aspect of the present invention, in the 38th aspect, the absorbent substance comprises at least one from the group consisting of highly absorbent crystals, hydrophilic colloids, and gel-forming materials. (40) A forty-third aspect of the present invention is a method for applying negative pressure to a wound, the step of preparing a negative pressure wound therapy (NPWT) bandage, the NPWT bandage being a membrane configured to be placed over a wound, such that a wound chamber is formed between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending through the membrane from the wound-side surface to the atmospheric-side surface, and a pump assembly supported by the membrane, the pump assembly comprising a pump body having a wall structure arranged around the pump chamber, the wall structure being at least a portion of which is elastic, a wound-side passage extending through the wall structure and communicating with the wound chamber, and a passage extending through the wall structure and connecting the pump chamber to the atmosphere. The present invention comprises: a pump assembly having an atmospheric passage; a canister configured to be in fluid communication with the wound chamber and the pump assembly, the canister including an internal chamber for collecting exudate exiting the wound chamber, wherein the pump assembly is configured to generate negative air pressure within the wound chamber so that exudate from the wound chamber flows out of the wound chamber into the internal chamber of the canister; positioning the NPWT bandage over the wound to form a wound chamber between the membrane and the wound; and generating negative air pressure within the wound chamber so that exudate flows from the wound chamber into the internal chamber of the canister. (41) According to a forty-first aspect of the present invention, in a forty-first aspect, the pump assembly and the canister are mounted on the membrane such that exudate exits the wound chamber, passes through the wound-side passage of the pump assembly, enters the pump chamber, passes through the air-side passage of the pump assembly, and flows into the internal chamber of the canister. (42) According to a forty-second aspect of the present invention, in a forty-first aspect, the pump assembly further comprises an atmospheric one-way valve located in the atmospheric passage of the pump assembly, the atmospheric one-way valve being configured to allow seepage to flow from the pump chamber through the atmospheric passage into the internal chamber of the canister, but to prevent seepage from flowing from the internal chamber of the canister through the atmospheric passage into the pump chamber. (43) According to a forty-third aspect of the present invention, in a forty-third aspect, the pump assembly and the canister are mounted on the membrane such that the exudate flows out of the wound chamber and directly into the internal chamber of the canister. (44) According to a forty-fourth aspect of the present invention, in a forty-third aspect, the pump assembly further comprises a wound-side one-way valve disposed within the wound-side passage of the pump assembly, the wound-side one-way valve being configured to allow fluid to flow from the internal chamber of the canister through the wound-side passage to the pump chamber, but to prevent fluid from flowing from the pump chamber through the wound-side passage to the internal chamber of the canister. (45) According to a forty-fifth aspect of the present invention, in a forty-fifth aspect, the canister and the pump assembly are mounted on the atmospheric surface of the membrane. (46) According to a forty-sixth aspect of the present invention, in a forty-sixth aspect, the canister is mounted on the atmospheric surface of the membrane, and the pump assembly is mounted on the canister such that the canister is positioned between the atmospheric surface of the membrane and the pump assembly. (47) According to the 47th aspect of the present invention, in the 40th aspect, the canister further includes an atmospheric opening. (48) According to the 48th aspect of the present invention, in the 47th aspect, the atmospheric opening includes a gas permeable membrane, the gas permeable membrane allowing a gas to pass through the membrane. (49) According to the 49th aspect of the present invention, in the 48th aspect, the gas permeable membrane prevents the liquid from passing through the gas permeable membrane. (50) According to a 50th aspect of the present invention, in a 40th aspect, the canister is integrally formed with the pump body. (51) According to the 51st aspect of the present invention, in the 40th aspect, the canister is formed separately from the pump body. (52) According to a 52nd aspect of the present invention, in a 40th aspect, the internal chamber of the canister further comprises an absorbent material for absorbing the liquid present in the internal chamber of the canister. (53) According to a 53rd aspect of the present invention, in a 52nd aspect, the absorbent substance comprises at least one from the group consisting of highly absorbent crystals, hydrophilic colloids, and gel-forming materials. (54) A 54th aspect of the present invention is a negative pressure wound therapy (NPWT) bandage for applying negative pressure to a wound, the NPWT bandage comprising a membrane configured to be placed over a wound, such that a wound chamber is formed between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending through the membrane from the wound-side surface to the atmospheric-side surface, and a pump assembly supported by the membrane, the pump assembly comprising a pump body comprising a wall structure arranged around the pump chamber, the wall structure comprising at least a portion of which is elastic, and the wall structure A pump assembly comprising: a wound-side passage extending through a structure and communicating with the wound chamber through an opening in the membrane; and an atmospheric-side passage extending through the wall structure and connecting the pump chamber to the atmosphere; and a suction source configured to be connected to the pump assembly to establish negative air pressure in the wound chamber, wherein the pump body is substantially fully deployed when the negative air pressure in the wound chamber is below a predetermined threshold, and the pump body is substantially fully folded when the negative air pressure in the wound chamber is above the predetermined threshold. (55) According to the 55th aspect of the present invention, in the 54th aspect, the predetermined threshold is approximately 60 mmHg to approximately 180 mmHg. (56) According to a 56th aspect of the present invention, in a 54th aspect, the suction source is fluidly connected to the atmospheric passage of the pump assembly. (57) According to a 57th aspect of the present invention, in a 56th aspect, the suction source is fluidly connected to the atmospheric passage of the pump assembly using a Luer lock. (58) According to a 58th aspect of the present invention, in a 54th aspect, the suction source is configured to be removed from the pump assembly when the negative air pressure in the wound chamber exceeds a predetermined threshold. (59) According to a 59th aspect of the present invention, in a 58th aspect, the pump assembly further comprises a removable cap for fluid sealing the atmospheric passage of the pump assembly when the suction source is removed from the pump assembly. (60) According to the 60th aspect of the present invention, in the 54th aspect, the pump body includes a substantially cylindrical configuration. (61) According to the 61st aspect of the present invention, in the 60th aspect, when the pump body is in a substantially fully unfolded configuration, the pump body includes a substantially circular cross-section. (62) According to the 62nd aspect of the present invention, in the 60th aspect, when the pump body is in its substantially completely folded configuration, the wall structure of the pump body bends inward. (63) According to the 63rd aspect of the present invention, in the 54th aspect, when the pump body is in its substantially completely folded configuration, the wall structure of the pump body flexes inward to seal the pump chamber. (64) According to the 64th aspect of the present invention, in the 62nd aspect, a notch is formed in the wall structure of the pump body. (65) According to the 65th aspect of the present invention, in the 64th aspect, there are no notches in at least two oppositely facing portions of the wall structure of the pump body, and the wall structure of the pump body can seal the pump chamber when the pump body is in its substantially fully folded configuration. (66) A 66th aspect of the present invention is a method for applying negative pressure to a wound, the step of preparing a negative pressure wound therapy (NPWT) bandage, the NPWT bandage being a membrane configured to be placed over a wound, such that a wound chamber is formed between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending through the membrane from the wound-side surface to the atmospheric-side surface, and a pump assembly supported by the membrane, the pump assembly comprising a pump body having a wall structure arranged around the pump chamber, the wall structure being at least a portion of which is elastic, and a wound-side passage extending through the wall structure and communicating with the wound chamber through the opening in the membrane, and through the wall structure The invention comprises a pump assembly having an atmospheric passage extending and connecting the pump chamber and the atmosphere, and a suction source configured to be connected to the pump assembly to establish negative air pressure in the wound chamber, wherein when the negative air pressure in the wound chamber is below a predetermined threshold, the pump body takes a substantially fully unfolded configuration, and when the negative air pressure in the wound chamber is above the predetermined threshold, the pump body takes a substantially fully folded configuration; positioning the NPWT bandage over the wound to form the wound chamber between the membrane and the wound; and connecting the suction source to the pump assembly to generate negative air pressure in the wound chamber. (67) According to the 67th aspect of the present invention, in the 66th aspect, the predetermined threshold is approximately 60 mmHg to approximately 180 mmHg. (68) According to the 68th aspect of the present invention, in the 66th aspect, the suction source is fluidly connected to the atmospheric passage of the pump assembly. (69) According to the 69th aspect of the present invention, in the 68th aspect, the suction source is fluidly connected to the atmospheric passage of the pump assembly using a Luer lock. (70) According to a 70th aspect of the present invention, in a 66th aspect, the step of removing the suction source from the pump assembly when the negative air pressure in the wound chamber exceeds a predetermined threshold is further included. (71) According to a 71st aspect of the present invention, a 70th aspect further includes the step of attaching a removable cap to the atmospheric passage of the pump assembly while the suction source is removed from the pump assembly, thereby fluid-sealing the atmospheric passage of the pump assembly. (72) According to the 72nd aspect of the present invention, in the 66th aspect, the pump body includes a substantially cylindrical configuration. (73) According to the 73rd aspect of the present invention, in the 72nd aspect, when the pump body is in a substantially fully unfolded configuration, the pump body includes a substantially circular cross-section. (74) According to a 74th aspect of the present invention, in a 72nd aspect, when the pump body is in its substantially completely folded configuration, the wall structure of the pump body bends inward. (75) According to the 75th aspect of the present invention, in the 66th aspect, when the pump body is in its substantially completely folded configuration, the wall structure of the pump body flexes inward to seal the pump chamber. (76) According to the 76th aspect of the present invention, in the 74th aspect, a notch is formed in the wall structure of the pump body. (77) According to the 77th aspect of the present invention, in the 76th aspect, there are no notches in at least two oppositely facing portions of the wall structure of the pump body, and the wall structure of the pump body can seal the pump chamber when the pump body is in its substantially fully folded configuration. (78) A 78th aspect of the present invention is a negative pressure wound therapy (NPWT) bandage for applying negative pressure to a wound, the NPWT bandage comprising a membrane configured to be placed over a wound, such that a wound chamber is formed between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending through the membrane from the wound-side surface to the atmospheric-side surface, and a pump assembly supported by the membrane, the pump assembly comprising a pump body comprising a wall structure arranged around the pump chamber, the wall structure comprising at least a portion of which is elastic, and the wall A pump assembly comprising a wound-side passage extending through a structure and communicating with the wound chamber through an opening in the membrane, and an atmospheric-side passage extending through a wall structure and connecting the pump chamber to the atmosphere, and a connector for connecting a suction source to the pump assembly to establish negative air pressure in the wound chamber, wherein the pump body is substantially fully deployed when the negative air pressure in the wound chamber is below a predetermined threshold, and the pump body is substantially fully folded when the negative air pressure in the wound chamber is above the predetermined threshold. (79) A 79th aspect of the present invention is a negative pressure wound therapy (NPWT) bandage for applying negative pressure to a wound, the NPWT bandage comprising a membrane comprising a first portion configured to be positioned over the wound and a second portion configured to extend laterally away from the wound, the first portion configured to be positioned over the wound so as to form a wound chamber between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface and an opening extending from the wound-side surface to the atmospheric-side surface, the opening being in fluid communication with the wound chamber, A pump assembly supported by the second portion of the membrane, the pump assembly comprising: a pump body having a wall structure arranged around a pump chamber, the wall structure being at least a portion of which is elastic; a wound-side passage extending through the wall structure and communicating with the wound chamber through the opening in the membrane; and an atmospheric-side passage extending through the wall structure and connecting the pump chamber to the atmosphere, wherein the pump assembly is configured to generate negative air pressure within the wound chamber. (80) According to the 80th aspect of the present invention, in the 79th aspect, the film comprises a plurality of layers. (81) According to an 81st aspect of the present invention, in an 80th aspect, the membrane comprises a substantially air-impermeable layer and an absorbent layer, wherein the absorbent layer is located on the wound side of the membrane. (82) According to an 82nd aspect of the present invention, the 81st aspect further includes an additional layer, the absorbent layer being positioned between the substantially air-impermeable layer and the additional layer. (83) According to the 83rd aspect of the present invention, in the 79th aspect, the opening includes a first opening segment formed in the first portion of the membrane and a second opening segment formed in the second portion of the membrane, wherein the absorbent layer fluidly connects the first opening segment to the second opening segment. (84) According to the 84th aspect of the present invention, in the 79th aspect, the second portion of the membrane extends along the centerline of the first portion of the membrane, and the pump assembly is positioned along the centerline of the first portion of the membrane. (85) According to the 85th aspect of the present invention, in the 79th aspect, the second portion of the membrane extends at an angle with respect to the center line of the first portion of the membrane, and the pump assembly is positioned at an angle with respect to the center line of the first portion of the membrane. (86) According to the 86th aspect of the present invention, in the 85th aspect, the second portion of the film extends perpendicular to the center line of the first portion of the film. (87) According to the 87th aspect of the present invention, in the 79th aspect, the second portion of the membrane extends at an angle with respect to the center line of the first portion of the membrane, so as to position the pump assembly parallel to the center line of the first portion of the membrane. (88) According to the 88th aspect of the present invention, in the 79th aspect, the pump assembly is mounted on the second portion of the membrane by a pair of bases, and one of the bases further includes the wound-side passage of the pump assembly. (89) According to the 89th aspect of the present invention, in the 88th aspect, the pump body is suspended between the pair of bases and spaced apart from the membrane. (90) According to the 90th aspect of the present invention, in the 79th aspect, a notch is formed in the wall structure of the pump body. (91) A 91st aspect of the present invention is a method for applying negative pressure to a wound, comprising the steps of preparing a negative pressure wound therapy (NPWT) bandage, the NPWT bandage being a membrane comprising a first portion configured to be positioned over the wound and a second portion configured to extend laterally away from the wound, the first portion being positioned over the wound to form a wound chamber between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface and an opening extending from the wound-side surface to the atmospheric-side surface, the opening being in fluid communication with the wound chamber, and a pump assembly supported by the second portion of the membrane, the pump assembly comprising a wall structure positioned around the pump chamber A pump assembly comprising: a pump body having at least a portion of the wall structure being elastic; a wound-side passage extending through the wall structure and communicating with the wound chamber through an opening formed in the membrane; and an atmospheric-side passage extending through the wall structure and connecting the pump chamber to the atmosphere, wherein the pump assembly is configured to generate negative air pressure in the wound chamber; a step of positioning the first portion of the NPWT bandage over the wound to form a wound chamber between the membrane and the wound; a step of positioning the second portion of the membrane on a biological structure laterally offset from the wound; and a step of generating negative air pressure in the wound chamber. (92) According to the 92nd aspect of the present invention, in the 91st aspect, the film comprises a plurality of layers. (93) According to a 93rd aspect of the present invention, in a 92nd aspect, the membrane comprises a substantially air-impermeable layer and an absorbent layer, wherein the absorbent layer is located on the wound side of the membrane. (94) According to a 94th aspect of the present invention, in a 93rd aspect, an additional layer is further included, wherein the absorbent layer is positioned between the substantially air-impermeable layer and the additional layer. (95) According to a 95th aspect of the present invention, in a 91st aspect, the opening includes a first opening segment formed in the first portion of the membrane and a second opening segment formed in the second portion of the membrane, wherein the absorbent layer fluidly connects the first opening segment to the second opening segment. (96) According to the 96th aspect of the present invention, in the 91st aspect, the second portion of the membrane extends along the centerline of the first portion of the membrane, and the pump assembly is positioned along the centerline of the first portion of the membrane. (97) According to the 97th aspect of the present invention, in the 91st aspect, the second portion of the membrane extends at an angle with respect to the center line of the first portion of the membrane, and the pump assembly is positioned at an angle with respect to the center line of the first portion of the membrane. (98) According to the 98th aspect of the present invention, in the 97th aspect, the second portion of the film extends perpendicular to the center line of the first portion of the film. (99) According to a 99th aspect of the present invention, in a 91st aspect, the second portion of the membrane extends at an angle with respect to the center line of the first portion of the membrane, so as to position the pump assembly parallel to the center line of the first portion of the membrane. (100) According to a 100th aspect of the present invention, in a 91st aspect, the pump assembly is mounted on the second portion of the membrane by a pair of bases, and one of the bases further includes the wound-side passage of the pump assembly. (101) According to the 101st aspect of the present invention, in the 100th aspect, the pump body is suspended between the pair of bases and spaced apart from the membrane. (102) According to the 102nd aspect of the present invention, in the 91st aspect, a notch is formed in the wall structure of the pump body. (103) A 103rd aspect of the present invention is a negative pressure wound therapy (NPWT) bandage for applying negative pressure to a wound, the NPWT bandage being a membrane configured to be placed over a wound, so as to form a wound chamber between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending from the wound-side surface to the atmospheric-side surface, the opening being in fluid communication with the wound chamber, the membrane comprising a permeable layer and an absorbent layer, the absorbent layer being located on the wound side of the membrane, the absorbent layer comprising a plurality of windows extending through the absorbent layer, and further comprising the permeable layer and the membrane The plurality of windows in the absorbent layer enable visualization of the wound through the membrane; a membrane; and a pump assembly supported by the membrane, the pump assembly comprising a pump body having a wall structure defining a pump chamber, with at least a portion of the wall structure being elastic; a wound-side passage extending through the wall structure and communicating with the wound chamber through the opening in the membrane; and an atmospheric-side passage extending through the wall structure and connecting the pump chamber to the atmosphere, the pump assembly configured to generate negative air pressure within the wound chamber. (104) According to the 104th aspect of the present invention, in the 103rd aspect, the film further comprises an additional layer, the absorbent layer being positioned between the permeable layer and the additional layer. (105) According to a 105th aspect of the present invention, in a 103rd aspect, the plurality of windows are configured to be used as visual indicators for determining whether the NPWT bandage needs to be removed from the wound. (106) According to the 106th aspect of the present invention, in the 103rd aspect, the membrane further includes a plurality of markings for aligning the NPWT bandage over the wound. (107) According to the 107th aspect of the present invention, in the 106th aspect, the plurality of markings are formed on at least one of the permeable layer and the absorbent layer. (108) According to the 108th aspect of the present invention, in the 103rd aspect, the film further includes serrations on the outer circumference. (109) According to the 109th aspect of the present invention, in the 108th aspect, the outer periphery serrations are formed on at least one of the permeable layer and the absorbent layer. (110) According to the 110th aspect of the present invention, in the 103rd aspect, the membrane includes a first portion configured to be positioned over the wound to form the wound chamber, and a second portion configured to extend laterally away from the wound. (111) According to a 111th aspect of the present invention, in a 110th aspect, the pump assembly is mounted on the second portion of the membrane so that the pump assembly is offset laterally from the wound. (112) According to a 112th aspect of the present invention, in a 110th aspect, the pump assembly is attached to the first portion of the membrane so that the pump assembly is centered over the wound. (113) According to the 113th aspect of the present invention, in the 103rd aspect, the wall structure of the pump body includes a notch. (114) A 114th aspect of the present invention is a bandage for covering a wound that discharges exudate, the bandage comprising a membrane configured to be placed over the wound, such that a wound chamber is formed between the membrane and the wound, the membrane comprising a wound-side surface, an air-side surface, and an opening extending from the wound-side surface to the air-side surface, the opening being in fluid communication with the wound chamber, the membrane comprising a permeable layer and an absorbent layer, the absorbent layer being located on the wound side of the membrane, the absorbent layer comprising a plurality of windows extending through the absorbent layer, and further comprising the permeable layer of the membrane and the plurality of windows in the absorbent layer of the membrane, thereby enabling visualization of the wound through the membrane. (115) According to the 115th aspect of the present invention, in the 114th aspect, the film further includes serrations on its outer circumference. (116) According to the 116th aspect of the present invention, in the 115th aspect, the outer periphery serrations are formed on at least one of the permeable layer and the absorbent layer. (117) According to the 117th aspect of the present invention, in the 114th aspect, the membrane further includes a plurality of markings for aligning the bandage over the wound. (118) A 118th aspect of the present invention is a method for applying negative pressure to a wound, comprising the steps of preparing a negative pressure wound therapy (NPWT) bandage, the NPWT bandage being a membrane configured to be placed over a wound, such that a wound chamber is formed between the membrane and the wound, the membrane comprising a wound-side surface, an atmospheric-side surface, and an opening extending from the wound-side surface to the atmospheric-side surface, the opening being in fluid communication with the wound chamber, the membrane comprising a permeable layer and an absorbent layer, the absorbent layer being located on the wound side of the membrane, the absorbent layer comprising a plurality of windows extending through the absorbent layer, and further comprising the permeable layer of the membrane and the plurality of windows of the absorbent layer of the membrane, which enable visualization of the wound through the membrane, and a pump assembly supported by the membrane, the pump assembly The pump assembly comprises a pump body having a wall structure defining a pump chamber, the wall structure being elastic in at least a portion thereof; a wound-side passage extending through the wall structure and communicating with the wound chamber through an opening formed in the membrane; and an atmospheric-side passage extending through the wall structure and connecting the pump chamber to the atmosphere, wherein the pump assembly is configured to generate negative air pressure in the wound chamber; positioning the NPWT bandage over the wound to form the wound chamber between the membrane and the wound; generating negative air pressure in the wound chamber; and visualizing the absorbent layer of the membrane and determining whether the NPWT bandage needs to be removed from the wound and replaced with a new NPWT bandage. (119) According to the 119th aspect of the present invention, in the 118th aspect, the plurality of windows are configured to be used as visual indicators for determining whether the NPWT bandage needs to be removed from the wound. (120) According to the 120th aspect of the present invention, the 119th aspect further includes the step of removing the NPWT bandage from the wound when the number of windows adjacent to the area of ​​the absorbent layer showing exudate exceeds a predetermined threshold. (121) According to the 121st aspect of the present invention, in the 118th aspect, the film further comprises an additional layer, the absorbent layer being positioned between the permeable layer and the additional layer. (122) According to the 122nd aspect of the present invention, in the 118th aspect, the membrane further includes a plurality of markings for aligning the NPWT bandage over the wound. (123) According to the 123rd aspect of the present invention, in the 122nd aspect, the plurality of markings are formed on at least one of the permeable layer and the absorbent layer. (124) According to the 124th aspect of the present invention, in the 118th aspect, the film further includes serrations on its outer circumference. (125) According to the 125th aspect of the present invention, in the 124th aspect, the outer periphery serrations are formed on at least one of the permeable layer and the absorbent layer. (126) According to the 126th aspect of the present invention, in the 118th aspect, the membrane includes a first portion configured to be positioned over the wound to form the wound chamber, and a second portion configured to extend laterally away from the wound. (127) According to the 127th aspect of the present invention, in the 126th aspect, the pump assembly is mounted on the second portion of the membrane so that the pump assembly is offset laterally from the wound. (128) According to the 128th aspect of the present invention, in the 126th aspect, the pump assembly is attached to the first portion of the membrane so that the pump assembly is centered over the wound. (129) According to the 129th aspect of the present invention, in the 118th aspect, the wall structure of the pump body includes a notch. (130) A 130th aspect of the present invention is a method for covering a wound that discharges exudate, the method comprising the step of preparing a bandage, the bandage being a membrane configured to be placed over a wound, such that a wound chamber is formed between the membrane and the wound, the membrane comprising a wound-side surface, an air-side surface, and an opening extending from the wound-side surface to the air-side surface, the opening being in fluid communication with the wound chamber, the membrane comprising a permeable layer and an absorbent layer, the absorbent layer being the The method includes the steps of: positioning the bandage on the wound side of the membrane, wherein the absorbent layer includes a plurality of windows extending through the absorbent layer, and further, the permeable layer of the membrane and the plurality of windows in the absorbent layer of the membrane allow visualization of the wound through the membrane; positioning the bandage over the wound to form the wound chamber between the membrane and the wound; and visualizing the absorbent layer of the membrane to determine whether the bandage needs to be removed from the wound and replaced with a new bandage. (131) According to the 131st aspect of the present invention, in the 130th aspect, the film further includes serrations on its outer circumference. (132) According to the 132nd aspect of the present invention, in the 131st aspect, the outer periphery serrations are formed on at least one of the permeable layer and the absorbent layer. (133) According to the 133rd aspect of the present invention, in the 130th aspect, the membrane further includes a plurality of markings for aligning the bandage over the wound. (134) According to the 134th aspect of the present invention, in the 130th aspect, the plurality of windows are configured to be used as visual indicators for determining whether the bandage needs to be removed from the wound. (135) According to a 135th aspect of the present invention, the 134th aspect further includes the step of removing the bandage from the wound when the number of windows adjacent to the area of ​​the absorbent layer showing exudate exceeds a predetermined threshold.

Claims

1. A negative pressure wound therapy (NPWT) bandage for applying negative pressure to a wound, wherein the NPWT bandage is A membrane configured to be placed over a wound, wherein a wound chamber is formed between the membrane and the wound, the membrane comprising a wound-side surface, an air-side surface, and an opening extending through the membrane from the wound-side surface to the air-side surface, An assembly supported by the aforementioned membrane, wherein the assembly is A body comprising a wall structure arranged around an inner chamber, wherein at least a portion of the wall structure is elastic, A wound-side passage extends through the wall structure and communicates with the wound chamber through the opening in the membrane, It comprises an atmospheric passage extending through the wall structure and for connecting the inner chamber to the atmosphere, When a compressive force is applied to the wall structure of the main body, the fluid in the inner chamber is pushed out of the inner chamber through the passage on the atmospheric side, and thereafter, when the compressive force applied to the wall structure of the main body is reduced, the elasticity of the wall structure causes the main body to assume a substantially fully unfolded configuration, and the fluid in the wound chamber is drawn back into the inner chamber through the passage on the wound side, the assembly and A connector for connecting a suction source to the inner chamber of the assembly in order to establish negative air pressure within the wound chamber, Equipped with, The suction source is configured to increase the negative pressure inside the wound chamber. The main body is configured to provide an automatic pressure limiter for limiting the level of negative pressure in the wound chamber, When the negative air pressure in the wound chamber is below a predetermined threshold, the main body assumes the substantially fully unfolded configuration, and when the negative air pressure in the wound chamber exceeds the predetermined threshold, the main body assumes the substantially fully folded configuration. The body is configured such that, when the body is in the substantially fully folded configuration, at least two oppositely opposing side wall portions of the wall structure of the body engage with each other to automatically seal the inner chamber, and the suction source prevents the negative air pressure in the wound chamber from increasing beyond a predetermined threshold. NPWT bandage.

2. The NPWT bandage according to claim 1, further comprising a suction source configured to be connected to the inner chamber of the assembly in order to establish negative air pressure within the wound chamber.

3. The NPWT bandage according to claim 2, wherein the predetermined threshold is approximately 60 mmHg to approximately 180 mmHg.

4. The NPWT bandage according to claim 2, wherein the suction source is fluidly connected to the atmospheric passage of the assembly.

5. The connector is equipped with a Luer lock, The NPWT bandage according to claim 4, wherein the suction source is fluidly connected to the atmospheric passage of the assembly using the Luer lock.

6. The assembly comprises a one-way valve located in the atmospheric passage, the one-way valve being configured to allow fluid to exit the inner chamber through the atmospheric passage but to prevent fluid from entering the inner chamber through the atmospheric passage. The NPWT bandage according to claim 4, wherein the suction source is configured to be removable from the assembly after the negative air pressure in the wound chamber has been established.

7. The NPWT bandage according to claim 6, further comprising a removable cap for fluid sealing the atmospheric passage of the assembly when the suction source is removed from the assembly.

8. The NPWT bandage according to claim 2, wherein the body comprises a substantially cylindrical configuration, and when the body is in the substantially fully unfolded configuration, the body comprises a substantially circular cross-section.

9. The NPWT bandage according to claim 2, wherein when the main body is in the substantially completely folded configuration, the wall structure of the main body flexes inward.

10. The NPWT bandage according to claim 9, wherein a plurality of notches are formed in the wall structure of the main body, and there are no notches in at least two oppositely opposing portions of the wall structure of the main body, and the wall structure of the main body seals the inner chamber when the main body is in the substantially completely folded configuration.

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