The present invention is directed to a support device, and more particularly to a support device that can apply a positive pressure to a user.
Pressure wounds (also known as pressure ulcer or bedsores) are a common affliction for bedridden patients, or persons that otherwise spend extended periods of time in a supine or prone position, or even in a sitting position. The pathophysiology of pressure wounds can vary from patient to patient, but the primary cause of pressure ulcers is tissue hypoxia. In particular, when the patient's skin is pressed between relatively hard surfaces, such as bone and a mattress, the skin vasculature is compressed, which reduces the delivery of oxygen to the compressed area. This hypoxia causes tissue injury, which in turn induces an inflammatory response, and can subsequently induce further hypoxia by increasing the extracellular fluid content of the tissue. The injured area can protrude further outwardly, causing more point pressure, which in turn causes more hypoxia.
The current primary approach to preventing pressure wounds is the implementation of pressure offloading. This entails minimizing pressure points with a specialized mattress or surface, and frequent turning/moving of the patient. However these approaches do not satisfactorily address the formation and/or treatment of pressure wounds.
The current disclosure is directed to an improved positive pressure system which can reduce the occurrence of pressure wounds. More particularly, in one embodiment the invention is a support device including a plurality of cells, each cell being at least partially defined by a cell wall, a chamber, and a plurality of valves. Each valve is movable between an open position where the valve provides fluid communication between an associated cell and the chamber, and a closed position wherein the valve generally blocks fluid communication between the associated cell and the chamber. Each valve is configured to be biased to a closed position during use of the device. The device is configured such that when a predetermined force is applied to each cell during use the associated valve moves to the open position.
With reference to
Each cell 14 can be open ended and have mouth 20 at its upper/distal end, and in the illustrated embodiment has a base wall 22 that divides the cell 14 into an upper or distal cell portion 24 and a lower or base cell portion 26. The mouth 20 of each cell 14 can have a variety of sizes/surface areas, but in one case has a surface area of between about 0.25 square inches and about 9 square inches (or greater than about 0.25 square inches and/less than about 9 square inches), and in another case of between about 1 square inch and about 4 square inches (or greater than about 1 square inch and/or less than about 4 square inches) to provide the desired performance as will be described in greater detail below. Each cell 14 can open at an upper/distal end thereof defining the mouths 20, and mouths 20/distal ends of the cell walls 18 can generally aligned to provide the surface 16 against which a user's body 30 can be positioned, as will be described in greater detail below. The device 10 can be configured such that the upper surface 16 of the mat 12 is at least about 50% voids/open spaces (e.g. not defined by the cell walls 18) in one case, or at least about 70% voids/open spaces in another case, or at least about 90% voids/open spaces in another case, to provide desired fluid flow as will be described in greater detail below.
With reference to
In one case each cell wall 18 is shared with any adjacent cell 14 such that there are no gaps positioned therebetween. The cell wall 18 of each cell 14 can be formed as a unitary, seamless, one-piece structure with each adjacent cell 14 and/or with the associated base wall 22. Each cell wall 18 can be formed as a vertically extending/aligned structure, where “vertical” is defined in one case with respect to a gravitational frame of reference and when the device 10/mat 12 is arranged with the mouths 20 of the cells 14 facing upwardly, as shown in
In the illustrated embodiment of
The system 10 can further include a chamber 34 positioned adjacent to or below the cells 14, where the chamber 34 is in selective fluid communication with the cells 14. In particular the chamber 34 can include a first (upper) 36 and second (lower) 38 wall that (along with other walls, not shown) define the sealed or generally sealed chamber 34 therebetween. The chamber 34 can be fluidly coupled to a fluid source 40 (see
The fluid provided by the fluid source and utilized by the device 10 can take any of a variety of forms, such as air, oxygen enriched air, oxygen (e.g. 90% or more oxygen by volume and/or mass), or other gases or fluids, including in some cases liquids such as water. The fluid may also be heated above or below ambient temperature and set at specific temperatures, and/or be modulated in various ways, such as temperature, air flow, or acoustics. In one case, the fluid in the chamber 34 and/or the cells 14 can be vibrated, in one case at about 47 Hz at about 4-6 dB to provide further therapeutic effects.
A valve 44 can be coupled to or included in each cell 14, where each valve 44 is configured to provide selective fluid communication between the chamber 34 and the associated cell 14/upper cell portion 24. In the embodiment shown in
Each stem 46 can include an opening 54 formed therein. The valves 44/stems 46 can be biased to their closed position, as shown in
The cells 14, including the cell walls 18, and optionally the base walls 22 and/or stems 46, can each be made of a relatively soft/pliable material. For example, the cell walls 18, and optionally the base walls 22 and/or stems 46 can be made of a variety of materials including foams and/or rubbers of silicone, neoprene, nitrile, gum, and latex, polymers or plastics such as polycarbonate, polyurethane, polyphenylene oxide, polyethylene terephthalate glycol, poly lactic acid, acrylonitrile butadiene styrene, and polyester, composite materials, and adhesives. The materials can have a variety of stiffness, in one case having a Young's modulus ranging from about 0.001 GPa to about 4 GPa. In some cases the cells 14 and cell walls 18 are made of an airtight material, but in other cases may have some limited air permeability, such as a permeability of less than about 0.001 cm3*cm/(s*cm2*cmHg), or less than about 60 cm3*cm/(s*cm2*cmHg), or between about 0.001 cm3*cm/(s*cm2*cmHg) and about 60 cm3*cm/(s*cm2*cmHg). Each cell wall 18 can be sufficiently stiff and have sufficient structural integrity to be maintained in the configuration shown in
By making the cells 14, cell walls 18, and optionally the base wall 22 and/or stem 46 of such a relatively soft/pliable material, the cells 14 can elastically deform when a user 30 lies or places sufficient body weight on the device 10/mat 12/cells 14. In particular, as shown in
This movement of the stems 46 can cause the lower/inner end of the stem 46 to protrude into the chamber 34, to a sufficient extent that the opening 54 of the stem 46 is exposed to the pressurized fluid in the chamber 34. Each valve 44 can thus be opened to allow fluid to enter the cell 14 at an opposite end of the cell 14 relative to the mouth 20/distal end. In this manner the system 10 can be configured such that each valve 44 is movable to an open position when sufficient force is applied to as associated cell 14/cell wall 18, and the force is only indirectly, and not directly, applied to the valve 44. The pressurized fluid then flows upwardly/outwardly through the exposed stem openings 54, reaching the upper cell portion 24 and then impinging upon or flowing over the user's body 30, as shown in
In this manner, when sufficient force or pressure is applied to a cell 14/cell wall 18, the associated valve 44 is opened and allows fluid to flow through the cell 14 and toward/over the user's body 30. The flow of fluid, such as oxygenated air, can thereby provide oxygen or other desired fluids, gases, compounds, elements, medicinal components or the like to the user's body 30 and help to reduce the occurrence of and/or healing of pressure wounds. The size, shape, and deformation of the cells 14 is configured to provide desired therapeutic benefits. In particular, it is noted that when a user 30 lies upon or applies sufficient force/pressure to a cell 14/cell wall 18 to allow fluid to flow therethrough, the user's body 30 can form at least a partial seal with the mouth 20/cell 14 since the user's body 30 can span or cover the mouth 20/cell 14. This can create a plurality of discrete pockets of positive pressure to aid in healing and/or prevention of pressure wounds. In this manner, rather than relying on one large seal to provide an area of increased pressure as in some previous systems, the current device 10 can create multiple small pockets of increased pressure.
However, it is not expected that a user's body 30 will typically form a complete seal with the mouth 20/cell 14. In particular, as shown in
The ideal leak flow rate is dependent on various factors, including the content and nature of the fluid, but in one case can at least about 0.00045 cm3/cm2/s (for 100% oxygen in one case) or in another case at least about 0.002 cm3/cm2/min. The upper limit of the flow rate can be primarily determined based upon pump capacity, noise and comfort, and in one example could be about 0.3 cm3/cm2/min. as tolerated by the user 30, or about 0.8 cm3/cm2/min if there is significant air leak and/or as desired for increased dryness (a flow rate of about 5 liters per minute may be required to maintain fullness in the system 10/mat 12 for a user 30 lying on their back). In this manner a user's body 30 may form a sufficient seal to create a pocket of increased pressure (relative to ambient/environmental pressure) in the activated cells 14, but not form a complete seal to still allow fluid to flow through such cells 14.
When a user gets off of the mat 12/system 10 or otherwise reduces the weight/force applied to the mat 12/system 10, the valves 44/cells 14 return to their original, undeformed shape and position as shown in
Thus, pressurized fluid can flow through the valves 44, with each valve 44 being movable between an open position where the valve 44 provides fluid communication between an associated cell 14 and the chamber 34, and a closed position wherein the valve 44 generally blocks fluid communication between the associated cell 14 and the chamber 34. Each cell 14 will only produce a positive pressure when it is sufficiently depressed/activated and sufficiently covered. As shown in
Some case, such as cell 14′ of
Thus, if desired, in one case each cell 14/valve 44 can include a flow limiting device/shutoff mechanism 62, in the form of a stem flapper 64 in the illustrated embodiment, to limit the amount of flow through the cell 14/valve 44, and cause the valve 44 to close when too much fluid flows through the cell 14/valve 44. Each stem flapper 64 is positioned in the associated stem 46 is biased to a downwardly-angled, open position as shown in
When pressurized fluid is introduced into the chamber 34, each flapper component 66 can move to its closed position, as shown in
When a user 30 lies upon or applies sufficient force/pressure to a cell 14, those cells 14 are compressed and the cell walls 18 deform, as shown in
In this manner, again, pockets of positive pressure are applied against the user 30 to reduce the development of pressure wounds. If there is an excessive flow of fluid though cell 14 (e.g. in one case due to a user's body lifting off the mat 12 at gap 60 of
The embodiment of
In the embodiment of
The device 10/mat 12 can also be configured to be wrapped or pressed against other portions of the user's body 30, such as legs, torso, neck, head, or other appendages. Thus, the device 10 can be configured such that when the device 10 is sufficiently pressed against the user's body 30, such as via gravitational forces applied by the user's body, or by compression or other forces, certain cells 14/valves 44 are activated to provide the pockets of positive pressure and the associated therapeutic benefits.
Having described the invention in detail and by reference to the various embodiments, it should be understood that modifications and variations thereof are possible without departing from the scope of the claims of the present application.
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Number | Date | Country | |
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20230372171 A1 | Nov 2023 | US |