MX2008007045A - Wound exudate removal and isolation system - Google Patents

Abstract

A wound exudate removal and isolation system includes a porous dressing, a canister in fluid communication with the dressing, and a first valve positioned between the dressing and the canister. The first valve is positionable between an open position and a closed position. A disposal line is fluidly connected to the canister and includes a second valve that is positionable between an open position and a closed position. A pump is fluidly connected to the canister and is configured to draw wound exudate from the dressing into the canister when the first valve is open and the second valve is closed. The pump is configured to force wound exudate from the canister into the disposal line when the first valve is closed and the second valve is open.

Description

RETIREMENT SYSTEM AND INSULATION OF WOUND EXUDED CROSS REFERENCE TO RELATED REQUESTS This application claims the benefit of the Provisional Application of E.U. No. 60 / 742,755, filed on December 6, 2005, which is incorporated herein by reference. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention concerns wound management. More particularly, the present invention concerns a wound management system employing reduced pressure to remove wound exudate and a dressing that will contain and isolate the wound, where the dressing should remain on the wound for a prolonged period of time. 2. Description of Related Art The recent extensive operations in combat of the Armed Forces of the United States. both in Afghanistan and Iraq have been notable at the comparatively low level of fatalities compared to other conflicts involving the US military, such as combat operations in Vietnam. The reason for the comparatively low level of fatalities is due to the dramatic improvements that have been made in body armor protection and medical care. They have been made significant improvements to procedures and techniques to stabilize and remove injured personnel from the battlefield to an installation where medical care can be administered by personnel with the appropriate equipment. Although there has been a dramatic decrease in the loss of life, there has also been a corresponding increase in the number of injured members in service. As in many combat situations, a frequent injury in those who are in combat operations on land is a deep traumatic wound. Many traumatic military injuries are inherently contaminated and can become severely infected due to prolonged contact with the ground on the battlefield or prolonged periods without treatment. Field doctors have been taught how to irrigate and / or clean deep wounds and then cover the wound with some type of wound dressing. The wound dressing performs various functions. A dressing often includes a powder, an ointment, or a balm, which can destroy some of the toxic bacteria that have entered the wound. Second, the dressing covers the wound to help prevent the entry of additional toxic bacteria. Third, the dressing reduces the possibility of cross-contamination with other wounds in a patient's body. Fourth, the dressing absorbs fluids or exudates from the wound.

However, when the wounds are large or deep, various treatment problems arise. Because medical evacuation routes can extend thousands of miles, it is not uncommon for wounded soldiers to experience several days in the medical evacuation process. Although injured personnel are in transportation, it is usually not possible to provide the type of wound care available in a hospital. A gauze dressing may not have a sufficient capacity for fluid retention to adequately absorb all the exudate from some wounds, and, therefore, may be saturated with the exudate. Saturated dressings may not be easily changed by unsaturated dressings during medical evacuation and transport by aircraft or in land / water transport vehicles. A typical installation arrangement in medical transport / evacuation vehicles involves stacking up three or four patient stretchers, often against a support wall or wall. Such a stack of stretchers can limit access to the wounds that exude from those patients on the stretchers, so that medical personnel frequently can not monitor the dressings or any other equipment used to protect the wounds. During all parts of the medical evacuation process, there is a need to provide management of the Exuding wounds and isolating wounds by having the wound contained in a closed protective environment. There is also a need to remove and isolate wound exudate so that wound exudate, a biohazard material, can be collected and disposed of properly. Such removal and isolation of wound exudate will reduce cross-contamination, reduce the risk of infection and facilitate the effective management of wounds during transport of injured soldiers. There is a need to provide a system that is compact, so that it can be easily transported and that does not depend on any external energy source for its operation. Finally, there is a need to provide a system that is certified by the US Military Air Force, a non-expensive, disposable asset. SUMMARY OF THE INVENTION The problems presented by the existing systems and methods for the isolation of wounds are solved by means of the systems and methods of the present invention. A wound exudate removal and isolation system according to one embodiment of the present invention includes a porous dressing, a container in fluid communication with the porous dressing and a first valve positioned between the porous dressing and the container. The first valve is placed in an open position to allow the flow of fluid and in a closed position to prevent fluid flow between the porous pad and the container. A disposal conduit is fluidly connected to the container, and a second valve is operably located within the elimination conduit. The second valve is placed in an open position to allow fluid flow and in a closed position to prevent fluid flow through the elimination conduit. A pump is placed in fluid communication with the container and is operable to draw the exudate from the wound from the porous dressing to the container when the first valve is open and the second valve is closed. The pump is further operable to force exudate from the wound from the container to the elimination conduit when the first valve is closed and the second valve is open. According to another embodiment of the present invention, the wound treatment apparatus includes a means for bandaging a wound, a means for extracting the exudate from the wound into a container, a means for isolating the wound and a means for forcing the exudate. from the container. According to another embodiment of the present invention, the stasis and wound insulation apparatus includes an open cell reticulated foam dressing that it has an average pore size of less than about 200 microns. A cloth is provided to cover the foam dressing and the wound. A pump is placed in fluid communication with the foam pad to extract the wound exudate from the wound at a pressure of less than approximately 125 mmHg to maintain drainage of the wound and moisture control in the wound, but minimizing the development of fabric towards the foam dressing. In accordance with another embodiment of the present invention, there is provided a method for providing stasis and isolation to a wound. The method includes placing an open cell reticulated foam dressing adjacent to the wound, the foam dressing having an average pore size of less than about 200 microns. A cloth is placed over the foam dressing and the wound, and a reduced pressure of less than about 100 mmHg is applied to the foam dressing. Other objects, features and advantages of the present invention will become apparent with reference to the drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a simple illustration of a mode of the automatic, compact, wound exudate removal and isolation system described: Figure 2 is a schematic diagram of the system of removal and isolation of wound exudate according to Figure 1; and Figure 3 is a schematic diagram of an alternative embodiment of the wound exudate removal and isolation system in which a valve is activated by rotating the container. DETAILED DESCRIPTION OF A PREFERRED MODE In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings that are a part thereof, and in which are shown, by way of illustration, the specific preferred embodiments in which practice the invention. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is understood that other embodiments may be used and that logical, structural, mechanical, electrical and chemical changes may be made without departing from the essence or scope of the invention. . To avoid details not necessary to enable those skilled in the art to practice the invention, the description may omit certain information known to those skilled in the art. Accordingly, the following detailed description should not be taken in a limiting sense, and the scope of the present invention is defined solely by the appended claims.

Figure 1 is a simple illustration of the described automatic, compact wound exudate removal and isolation system 100 of the present invention. As shown in Figure 1, the system 100 provides collection and removal of wound exudate through a dressing, which can remain on a wound and be much more effective at typical dressing exchange intervals and throughout the medical evacuation process. Accordingly, the described system 100 protects the person with a wound, those who transport the person with the wound, and others in close proximity. The wound exudate removal and isolation system 100 provides a dressing and cover 110 over the wound, which extracts the exudate from the wound and moves the exudate to an exudate collection system 120 by applying a vacuum, or pressure reduced. With traditional reduced pressure delivery systems, the distribution of reduced pressure at the wound site is used to encourage the growth of new tissue. The wound exudate removal and isolation system 100 is preferably used to isolate, protect and provide stasis to the wound site until the patient arrives at a medical facility where the wound can be properly treated. Accordingly, the system 100 is configured to provide adequate drainage of the wound and moisture control capabilities, while minimizing the internal growth of new tissue within the dressing. Figure 2 is a schematic diagram of the wound exudate removal and isolation system 100 according to one embodiment of the present invention. As illustrated in Figure 2, a 1.0 porous dressing is used to create a protective environment over the wound. The dressing 1.0 is preferably formed of an open cell cross-linked foam. Alternatively, the dressing can be formed by other materials that are suitable for multiplying the pressure across the wound. For example, a solid sheet of material (e.g., a silicone sheet) having projections on one side may allow the distribution of pressure in the wound through the flow channels formed between the projections. Instead of, or in addition to the projections, small holes may be provided in the material sheet to allow pressure multiplication. Whatever type of dressing is used, dressing 1.0 should have the ability to distribute reduced pressure to properly remove the wound exudate away from the wound. Although the system 100 is not designed to encourage the growth of granulation tissue, studies have found that wounds exposed to reduced pressure can be granulated substantially in as little as 48 hours. To assist in the eventual removal and replacement of the dressings, the wound contact surface of dressing 1.0 is designed to minimize tissue growth thus facilitating contact beyond the typical dressing change intervals of 48-72 hours. When a foam dressing is used, dressing 1.0 includes pores of a size that allow wound exudate to pass from a wound into a 1.2 tube, but minimizes tissue development within the pores. The average pore size is typically between about 40 to 200 μm, and preferably about 100 μm. The pore sizes associated with dressing 1.0 are typically smaller than the pore sizes associated with the dressings used to promote wound healing. Porous dressing 1.0 can also have antimicrobial properties. In one embodiment, the dressing may be coated or impregnated with an antimicrobial agent such as silver. A cloth 1.1 is placed over the foam padding 1. 0 to isolate the wound and to allow the application of a reduced pressure to the wound 1.0 through the tube 1.2. In one embodiment, tube 1.2 is a plastic tube. The dressing 1.0, the cloth 1.1 and a tube 1.2 can be contained in a small lightweight equipment, which can Easily deploy with and stack up by military medical units. The reduced pressure applied to the dressing 1.0 is strong enough to continuously extract the exudate from the wound through the tube 1.2. unlike the reduced pressure systems that are used to promote the growth of granulation tissue in the wound, the main purpose of the system 100 is to isolate and contain wounds and remove the exudate. Although the reduced pressure applied to the wound through the dressing 1.0 can be adjusted depending on the size of the wound and the porosity of the dressing 1.0, it is preferred that the pressure applied to the wound be less than about 125 mmHg. This particular pressure is typically considered the minimum pressure at which the growth of new tissue in wounds is accelerated; hence, it is desired to remain below this pressure to minimize the growth of new tissue. More preferably, the pressure applied to the wound through the dressing will be between about 25 and 75 mmHg. Again, with reference to Figure 2 per illustration, a check valve 2 prevents backflow of the exudate into the wound. An in-line push-open valve 3 is in fluid communication with the check valve 2, placed downstream from the wound. Downstream from on-line throttle valve 3 to open, there is a non-removable drainable container 8 in fluid communication with the valve 3. In one embodiment, the container 8 can be drained and constructed of a rigid material. An elimination conduit 14 is fluidly connected to a drainage outlet 15 of the container 8. A valve 4 is located on the elimination conduit 14 in fluid communication with the container 8. Both valves 3, 4 can be selectively positioned already either in an open position or in a closed position to allow or prevent the flow of fluid through the valve 3, 4. Preferably placing the valve 3 in an open position results in the valve 4 being placed in a position closed. Similarly, placing the valve 3 in a closed position results in the valve 4 being placed in an open position. A cam pulley 5 operably connected to both valves 3, 4 can be found to mechanically coordinate the simultaneous positioning of the valves 3, 4. Since the system 100 can be placed in the wound for extended periods of time during transport of the patient, it may be desired to drain the container 8 while leaving the remainder of the system 100 in place. Valves 3, 4 are provided to allow drainage of container 8 when filled or when desired by the person attending the wound. During the application of pressure reduced to the wound, the valve 3 opens to provide a fluid communication between the dressing 1.0 and the container 8. In this configuration, the valve 4 is closed to prevent draining the container 8. To drain the container 8, the valve 3 is closed and valve 4 opens. The closing of the valve 3 prevents the reduced pressure from being applied to the wound, while the opening of the valve 4 allows the exudate of the wound in the container 8 to drain through the elimination conduit 14. Optionally, a container disposable 7 may be connected to the disposal conduit 14 for collecting the drained wound exudate from the container 8. The disposable container 7 may be a flexible, ventilated waste bag. When the disposable container 7 is filled, it can be removed and replaced with an empty container. The reduced pressure is provided to the dressing 1.0 through the container by a pump 11 which is fluidly connected to the container. In one embodiment, the pump 11 is a vacuum / pressure pump operated by batteries. Alternatively, the pump 11 may be operated manually, or may be any pump suitable for inducing the pressures described herein. As the pump 11 applies a reduced pressure to the dressing 1.0 through the container 8, the wound exudate is removed from the the wound and is deposited in the container 8. This operation occurs when the valve 3 is in an open position and the valve 4 is in a closed position. As previously described, the container 8 can be drained by placing the valve 3 in a closed position and the valve 4 in an open position. Although the drainage operation can be facilitated by the gravitational force, the wound exudate can alternatively be forced out of the container 8 into the elimination conduit 14 by means of the pump 11. To facilitate the forced draining of the container 8, a three-way valve tracks 9 is fluidly connected between the container 8 and the inlet of the pump 11. The valve 9 can be selectively positioned between an active position and a ventilation position. In the active position, the valve 9 allows fluid communication between the container and the inlet of the pump 11. In the ventilation position, the inlet of the pump 11 is vented. Another three-way valve 10 is connected fluidly between the container 8 and the outlet of the pump 11. The valve 10 can be selectively positioned between an active position and a ventilation position. In the active position, the valve 10 allows fluid communication between the container and the outlet of the pump 11. In the ventilation position, the outlet of the pump 11 is vented. The positioning of the valves 9, 10 is it is linked in such a way that the positioning of the valve 9 in the active position results in the positioning of the valve 10 in the ventilation position. Similarly, the positioning of the valve 9 in the ventilation position results in the positioning of the valve 10 in the active position. When the valve 9 is placed in the active position and the valve 10 is placed in the ventilation position, the pump 11 is configured to extract the exudate from the wound from the dressing 1.0 to the container 8. In this pressure setting reduced, the valve 3 is placed in the open position and the valve 4 is placed in the closed position. When the valve 9 is placed in the ventilation position and the valve 10 is placed in the active position, the pump 11 is configured to provide a positive pressure to the container to force the exudate from the wound from the container 8 to the duct of elimination 14. In this positive pressure configuration, valve 3 is placed in the closed position and valve 4 is placed in the open position. A hydrophobic filter 8.1 can also be included in fluid communication with the container 8 to prevent fluid from entering the tube attached to the pump 11 and valves 9 and 10.

In one embodiment, a sensor may be operably associated with the container 8 to detect when the container 8 is filled with the wound exudate. The sensor can be operably connected to the valves 3, 4, 9, 10 to automatically adjust the operation of the system 100 from the reduced pressure system to a positive pressure system so that the exudate moves from the container 8 to the disposable container 7 when the container 8 is full. The system may further include a security alarm system that provides either an audio signal or a visual signal if the system does not operate properly. The security alarm system is configured to avoid the production of false alarms in response to typical patient conditions that may arise during the medical evacuation process. However, some events that can be detected by means of the safety alarm system include, but are not limited to, leak detection events, lock events, full container events, low pressure events, high pressure events, and low battery events. The system may also include blood detection sensors to prevent exsanguination or withdrawal of copious or non-healthy amounts of blood from a patient. As shown in Figure 3, the valve that directs the flow of exudate can be activated manually by rotating the container 8. It should be apparent from the above that an invention having significant advantages has been provided. Although the invention is shown only in some of its forms, not only is it not limited, but it is susceptible to various changes and modifications without departing from its essence.

Claims (29)

1. CLAIMS 1. An apparatus for treating wounds, comprising: a porous dressing; a container in fluid communication with the porous dressing; a first valve positioned between the porous pad and the container and which can be placed in an open position to allow fluid flow, and in a closed position to prevent fluid flow between the porous pad and the container; a removal conduit fluidly connected to the container; a second valve operably positioned within the elimination conduit and which can be placed in an open position to allow fluid flow, and in a closed position to prevent fluid flow through the elimination conduit; and a pump in fluid communication with the container and operable to extract the exudate from the wound from the porous dressing to the container when the first valve is open and the second valve is closed, and the pump is operable to force the exudate from the container. the wound from the container to the elimination conduit when the first valve is closed and the second valve is open.
2. 2. The apparatus of claim 1, wherein the porous pad is an open cell cross-linked foam.
3. 3. The apparatus of claim 1, wherein the average pore size of the porous dressing is less than about 200 microns.
4. 4. The apparatus of claim 1, wherein the average pore size of the porous dressing is less than or equal to about 100 microns.
5. The apparatus of claim 1, wherein the porous dressing is comprised of a material that minimizes tissue development in the porous dressing.
6. The apparatus of claim 1, wherein the porous dressing includes an antimicrobial agent.
7. The apparatus of claim 1, further comprising: a third valve positioned between the container and the pump inlet, the third valve being positionable in an active position in which the container is in fluid communication with the inlet of the container. the pump and in a ventilation position in which the pump inlet is vented; and a fourth valve placed between the container and the outlet of the pump, the fourth valve being placeable in an active position in which the container is located in fluid communication with the pump outlet and in a ventilation position in which the pump outlet is ventilated.
8. The apparatus of claim 7, wherein: the pump is configured to draw the exudate from the wound from the porous dressing to the container when the third valve is in the active position and the fourth valve is in the position of ventilation; and the pump is configured to force exudate from the wound from the container to the elimination conduit when the third valve is in the ventilation position and the fourth valve is in the active position.
9. The apparatus of claim 1, further comprising a disposable container connectable to the elimination conduit for collecting the wound exudate from the container when the first valve is closed and the second valve is open.
10. The apparatus of claim 1, further comprising a sensor operably connected to the container and to the first and second valves to close the first valve and open the second valve when the exudate of the wound in the container reaches a predetermined level.
11. 11. The apparatus of claim 1, further comprising a check valve positioned between the porous dressing and the container to prevent backflow of the wound exudate from the container to the porous dressing.
12. The apparatus of claim 1, further comprising a security alarm to alert the operator if an event is detected that includes at least one of a leak detection event, a lock event, a full container event, a low pressure event, a high pressure event, and a low battery event.
13. The apparatus of claim 1, further comprising a blood detection sensor.
14. 14. An apparatus for treating wounds, comprising: means for bandaging a wound; means for extracting the exudate from the wound into a container; means for isolating the wound; and means for forcing the exudate from the container.
15. 15. The apparatus of claim 14, further comprising means for preventing backflow of the exudate to the wound wrapping means.
16. 16. The apparatus of claim 14, further comprising means for detecting the level of exudate extracted from the wound and operate the means to force the exudate into a waste container when the level reaches a predetermined level.
17. 17. The apparatus of claim 14, further comprising means for alerting the operator if an event is detected that includes at least one of a leak detection event, a block event, a full bin event, a bin event, and under pressure, a high pressure event, and a battery event.
18. 18. The apparatus of claim 14, further comprising means for preventing exsangumation.
19. 19. The apparatus of claim 14, further comprising: means for preventing backflow of exudate into the wound wrapping means; means for detecting the level of exudate extracted from the wound and for operating the means for forcing the exudate into a waste container when the level reaches a predetermined level; means to alert the operator if the device does not work; and means to prevent exsangumation.
20. 20. An apparatus for stasis and wound insulation, comprising: an open cell reticulated foam dressing having an average pore size of less than about 200 microns, with the placement of foamable foam adjacent to a wound; a cloth to cover the foam dressing and the wound; and a pump in fluid communication with the foam pad to extract the wound exudate from the wound at a pressure of less than about 125 mmHg to maintain drainage of the wound and moisture control in the wound, but minimize the development of the wound. tissue towards the foam dressing.
21. 21. The apparatus of claim 20, wherein the average pore size of the foam dressing is less than or equal to about 100 microns.
22. 22. The apparatus of claim 20, wherein the pore size of the foam dressing minimizes tissue development, but allows drainage of fluids from the wound.
23. 23. The apparatus of claim 20, wherein the pressure is between about 25 and 75 mmHg.
24. 24. The apparatus of claim 20, further comprising: a container positioned between the foam pad and the pump for collecting the exudate from the wound, the container having a drain outlet; Y wherein the pump is selectively operable to force exudate from the wound from the container through the drain outlet.
25. 25. The apparatus of claim 24, further comprising a disposable container that can be placed in fluid communication with the drain outlet to collect the exudate from the wound from the container.
26. 26. A method for providing stasis and insulation in a wound, comprising: placing an open cell reticulated foam dressing adjacent to the wound, the foam dressing having an average pore size of less than about 200 microns; place a cloth on the foam dressing and the wound; and applying a reduced pressure of less than about 100 mmHg to the foam dressing.
27. 27. The apparatus of claim 26, wherein the average pore size of the foam dressing is less than or equal to about 100 microns.
28. 28. The apparatus of claim 26, wherein the pore size of the foam pad minimizes tissue development, but allows drainage of fluids from the wound.
29. 29. The apparatus of claim 26, wherein the reduced pressure is between approximately 25 and 75 mmHg.