# Patent

## Title
Patient/invalid handling support

## Abstract

A patient support for supporting a patient includes an inflatable mattress having at least one bladder forming at least part of a patient support surface, a pneumatic system for inflating the inflatable mattress, and a control system. The control system including at least one sensor, which includes an emitter and a receiver, with the emitter directing light into the bladder. The receiver receives a reflection from the light directed into the bladder, and the control system detects the immersion of a patient into the mattress based on the reflection received by the receiver.

## Background
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority from U.S. Pat. application Ser. 61/301,901, filed Feb. 5, 2010, entitled PATIENT/INVALID HANDLING SURFACE, by Applicants Patrick Lafleche and Jean-Francois Girard, which is incorporated by reference herein in its entirety.


TECHNICAL FIELD AND BACKGROUND OF THE INVENTION
The present invention generally relates to a patient support, and more particularly to a patient mattress for a hospital bed.
SUMMARY OF THE INVENTION
The present invention provides a mattress for supporting a patient with a layer that provides both support to the patient and also optionally provides vibration and/or percussion treatment to the patient. For example, both these functions may be provided by the same layer. Further, as will be described below, the layer can provide proper patient envelopment to better distribute the pressure across the patient's body. Additionally, the layer may be flexible or adaptable so that it can be reconfigured to provide the desired treatment for a patient. The present invention also provides a patient mattress for supporting a patient with a layer that will provide vapor transmission away from the patient.
In one form of the invention, a patient mattress for supporting a patient includes a plurality of inflatable bladders and a control system for controlling the inflation of the inflatable bladders. Each of the bladders provides a patient facing side, which sides form a support surface configured for supporting the patient on the patient mattress. The control system is configured to control the flow of fluid to at least one of the inflatable bladders and provide the fluid at a sufficient pressure to generate a transient force at the support surface, which transient force can be applied to the patient supported on the mattress.
In one aspect, the control system is adapted to select the bladder from a group of bladders and to generate the transient force at the patient facing side of the selected bladder. For example, the control system may include a user input device wherein the control system selects the at least one bladder based on a signal from the user input device.
In another aspect, the control system is adapted to change the selection of the bladder to thereby vary the location of the transient force on the support surface. In yet another aspect, the control system is adapted to control the magnitude and/or duration of the transient force.
According to yet other aspects, the plurality of bladders may be arranged in groups, with the control system being adapted to control the pressure to a group of the bladders to thereby generate a transient force at the patient facing side of each of the bladders in the group.
In another aspect, each of the bladders has an inflated height, a transverse width, and a longitudinal width, with the inflated height being greater than at least one of the transverse width and the longitudinal width.
In yet another aspect, the mattress further includes a fluid movement device, such as pump, which is in selective fluid communication with the bladders and is controlled by the control system. Optionally, the pump is located in the mattress.
In another form of the invention, a patient mattress for supporting a patient includes a plurality of bladders, two or more delivery devices for delivering fluid to the bladders, and a control system for controlling the operation of the fluid delivery devices and selecting between the fluid delivery devices based on the desired inflation rate for the bladders. Suitable fluid delivery device include pumps or blowers.
In one aspect, the second fluid delivery device comprises two fluid delivery devices connected in series.
In yet another form of the invention, a patient mattress for supporting a patient includes a plurality of inflatable bladders, each bladder providing a patient facing side, the patient facing sides of the bladders forming a support surface configured for supporting the patient on the patient mattress, and a control system. The control system controls the inflation of the inflatable bladders and is configured to select at least one bladder from the plurality of bladders and to control the flow of fluid to the at least one bladder at a pressure to generate a transient force with the least one bladder to apply the transient force to a patient supported on the mattress. The control system is further configured to change the selection of the at least one bladder in response to a change in treatment protocol.
For example, the mattress may further include a user interface associated therewith, which is in communication with the control system, with the control system selecting the at least on bladder in response to input at the user interface. For example, the control system may be configured to change the selection of the at least on bladder in response a change in treatment protocol input at the user interface.
In other aspects, the bladders are arranged in manner to form a plurality of groups of bladders, and the control system is configured to select a group of the bladders and to control the flow of fluid to the selected group of bladders.
According to yet another form of the invention, a patient mattress includes a layer of bladders, each having an upwardly facing surface for facing and supporting the patient and being arranged in an array or matrix, and with the bladders being configured such that if one or more bladders are compressed by a part of the patient's body, the bladders surrounding the compressed bladder or bladders may remain partially uncompressed by that part of the patient's body and instead envelope that part of the patient's body to thereby distribute the weight of that part of the patient's body over a greater contact area than the bladder or bladders directly under that part of the patient's body. The mattress also includes a layer forming a protective layer between a patient supported on the bladders and the bladders, which is flexible and further leaves the bladders unrestrained by the layer when the bladders are compressed by the weight of a patient such that the layer does not interfere with the immersion of a patient into the mattress.
For example, the flexible layer may be formed by a plurality of flexible patches or panels located at the upwardly facing surfaces of at least a group of the bladders. Further, a suitable fabric for the flexible panels includes a spacer fabric or GORE-TEX®.
According to yet another form of the invention, a patient support includes a frame and a mattress having at least one inflatable bladder. The frame supports the mattress and includes at least one frame member forming a conduit for directing air through the frame member and the frame to the bladder.
In one aspect, the frame member forms a hinge for the frame. For example, the frame member may comprise a polymeric frame member. Further, the frame may comprise a plurality of the polymeric frame members and a plurality of side frame members, with the polymeric frame members interconnecting the side frame member to thereby hinge the side frame members together to allow articulation of the mattress about at least one axis. Optionally, each polymeric frame member may form two hinges.
According to yet another form of the invention, a patient support includes a mattress having an inflatable bladder and a frame having a pair of spaced apart frame sides, which supports the mattress. One of the frame sides forms a first housing and has a side frame member, which comprises a hollow member forming a conduit therethrough. A valve is located in the first housing, which is in fluid communication with the bladder, and a pump is in fluid communication with the valve through the conduit formed by the side frame member.
In one aspect, the pump may be located in the frame. For example, the frame may have a pair of spaced apart frame ends connected by the frame sides, with one of the frame ends forming a second housing, and the pump located in the second housing.
In another aspect, the pump and the valve are spaced a first distance, and the valve is spaced a second distance to the bladder, with the first distance being greater than the second distance so that valve is more closely spaced to the bladder than to the pump.
In yet other aspects, the patient support further includes a plurality of bladders and a second valve in communication with another bladder of the bladders. One of the frame sides forms a second housing, and the second valve is located in the second housing. Optionally, the frame includes a second side frame member forming a second conduit, with the pump in fluid communication with the second valve through the second conduit.
In any of these cases, each of the side frame members may comprise a polymeric side frame member with a plurality of corrugations in its respective sidewalls to thereby form hinges for the frame.
According to yet another form of the invention, a patient mattress includes a layer of inflatable bladders, each providing a patient facing side, with the patient facing sides of the bladders forming a support surface configured for supporting a patient on the patient mattress. The bladders are arranged in an array wherein the edges of the patient facing sides of longitudinally adjacent bladders are spaced from each other and the edges of the patient facing sides of laterally adjacent bladders are offset so as not generally align along a common axis. In this manner, the edges of the patient facing sides do not form linear gaps extending transversely or longitudinally across the mattress, which provides great continuity to the support surface formed by the bladders and increased comfort to the patient.
For example, the patient facing sides of the bladders may have multisided perimeters with either 3 sides or more than 4 sides. For example, the shape of the patient facing sides of the bladders may be hexagonal.
According to another form of the invention, a patient support for supporting a patient includes an inflatable mattress and a pneumatic system for inflating the inflatable mattress. The pneumatic system includes a reservoir for holding air, which air is then used to inflate the mattress.
In one aspect, the reservoir may be pressurized, with the flow air from the reservoir controlled by an outlet valve.
In a further aspect, the reservoir and outlet valve are configured to deliver air to the mattress with a pressure sufficient to generate a transient force at the support surface of the mattress to apply percussion or vibration treatment to a patient supported on the mattress. Optionally, the outlet valve is a fast response valve to let bursts of air into the mattress. For example, the pressure in the reservoir may be in a range of 0 psig to 15 psig, 2 psig to 15 psig, 2 psig to 12 psig, or 4 psig to 9 psig, including around 4.5 psig. As a result, the mattress can be filled quickly and further inflated and able to deliver percussion or vibration with the same air supply and the bladder inflation supply.
To reduce the turbulence in the pneumatic system, inserts may be provided, for example, in the outlet valve or the reservoir's, inlet. For example, the insert may be formed from a porous material, such as filter material, which can be used anywhere in pneumatic system to reduce turbulence and hence noise.
In another form of the invention, a patient support for supporting a patient includes an inflatable mattress and rails, which support the mattress and form a frame for the support. The rails incorporate channels for distributing air to the mattress. For example, the rails may be formed from plastic, metal, or a composite material. Additionally, the rails or at least a portion of the rails may be flexible to allow one or more sections of the patient support to pivot relative to the other sections of the patient support. The air channels may be formed by the rail itself or may be formed by tubes or tubing that extends through the rails.
In one aspect, the rails may be formed from hollow linkages that are pivotally joined together with passageways extending through the linkages.
In one form of the invention, a patient support for supporting a patient includes an inflatable mattress and a pneumatic system for inflating the inflatable mattress. The pneumatic system includes 2N pumps (where N is an integer) in 180° phase to cancel vibration. For example, one of the pumps has its electrical connection reversed from the other pump. Alternately, N number of pumps may be used in combination with N number of actuators having the same or substantially the same inertia, stroke, etc as the pump or pumps but in 180 degree phase from the pump to counter balance vibration of pump.
In any of the above mattresses, the inflatable mattress may be formed from a plurality of bladders. Further, one or more selected bladders may provide the percussion or vibration treatment.
In another form of the invention, a patient support for supporting a patient includes an inflatable mattress and a pneumatic system for inflating the inflatable mattress. The inflatable mattress includes a plurality of bladders. When inflated, the bladders are inflated to a volume that is less than their full volume so that the bladders are in an un-stretched state when inflated. Further, when the bladders are operated and the pressure in the bladders falls below a preselected threshold value, the pressure in the bladders is increased but the volume is still maintained below the full volume of the bladders.
In one aspect, when air is directed to the bladders to apply percussion or vibration, the volume of the bladders is still maintained below their full volume to thereby reduce fatigue in the material forming the bladders.
In any of the above mattresses, the inflatable mattress may be formed from a plurality of pod-like bladders that are arranged in an array.
In yet another form of the invention, a patient support for supporting a patient includes an inflatable mattress and a pneumatic system for inflating the inflatable mattress. The pneumatic system includes a CPR valve that is manually actuatable between a closed configuration where the flow of air from the mattress is blocked at the CPR valve, and an open position where the air can flow from the mattress through the CPR valve, and further configured to auto reset to its closed position after a CPR event.
In one aspect, the patient support further includes a control system in communication with the CPR valve. The control system is configured to trigger the CPR valve to auto reset to its closed position. In a further aspect, the control system includes a user input device, such as a touch actuatable device, such as a button, including a touch screen button, which is configured to trigger the CPR valve to auto reset to its closed position upon an input at the user input device.
For example, the CPR valve may include housing with two chambers, one in fluid communication with the mattress and the other in selective fluid communication with the atmosphere. The housing includes an outlet, and a check valve and an electrically controlled valve fluid communication with the second chamber. Positioned in the housing are a piston and a spring, which biases the piston to a closed position wherein the outlet is isolated from the first chamber. The piston is coupled to an actuator, which when actuated moves the piston against the force of the spring and past the outlet so that the first chamber is in communication with the atmosphere, and the air from the mattress can discharge through the outlet. When the piston is moved to its open position air from the second chamber is discharge though the check valve, which generates a vacuum in the second chamber, which holds the piston its open position. Once the CPR event is over, the user input device may be actuated to trigger the electrically operate valve to open to release the vacuum pressure to allow the spring to return the piston to its closed position.
In a further aspect, the actuator comprises a strap. Further, straps may be provided at both sides of the mattress. Optionally, the mattress may include two CPR valves or may a have a single valve that is actuated by actuators on either side of the mattress. For example, the actuator may include a cable system to which both actuators are coupled, with the cable system then coupled to the piston.
In another form of the invention, a patient support for supporting a patient includes an inflatable mattress and a pneumatic system for inflating the inflatable mattress. The inflatable mattress includes a plurality of bladders arranged in an array, which form the support surface for the patient. The patient support also includes a low air loss system for directing air between the bladders and toward the support surface.
For example, the low air loss system may include either separate tubing or tubing formed by the sheets or membrane forming the bladders. Furthermore, the bladders may extend under the bladders with the bladders being supported on or formed on a base sheet or membrane with openings to allow the air to flow upward between the bladders. Alternately, the tubing may run between the bladders. Additionally, the tubing may be supplied air by the pneumatic system or a separate pneumatic system. Further, the low air loss system may have tubing or tube extensions or perforated bladders that extend upwardly between the support bladders to direct air closer to the interface between the patient and the support surface provided by the bladders.
In yet another embodiment, the low air loss system may be formed by a diffusing element or layer between the bladders and a cover that may envelope the bladders.
In any of the above embodiments, the pneumatic system may incorporate one or more pumps, with at least one of the pumps taking air in from and/or discharging air into a canister, which is sized to reduce the noise of the respective pump. When both the intake and discharge canister are used, they may be incorporated into a single assembly to facility assembly of the mattress. The size of each chamber is selected so that it has sufficient volume to achieve desired noise reduction.
In another form of the invention, a patient support for supporting a patient includes an inflatable mattress and a pneumatic system for inflating the inflatable mattress. The inflatable mattress includes a plurality of support bladders arranged in an array, which form the support surface for the patient. The bladders may be each rounded or multisided and arranged so that each of their upper outer perimeter edges do not align with the edges of their adjacent bladders to form a continuous straight gap there between that spans the width or length of the support surface. For example each bladder has a vertical axis, a lateral axis, and a cross-section about their vertical axis. Their cross-sections may be circular or oval or generally peanut-shaped or may have three or more than four sides, such as a hexagon. In addition, additional bladders, such as bolster bladders, may be provided that flank or at least partially surround the support bladders and may extend, for example, under the arms and head of the patient. The bolster bladders may have rectangular cross-sections.
The height (H) of at least the central group of the support bladders is greater than their respective widths (W) and further preferably such that H>2W, and for example, with a height that falls in a range of 4-10 inches, 5-9 inches, or 6-8 inches, and may be 6′′. For example, the height of the support bladders under the body may be 6 inches, and the height of the bolster bladders may be in a range of 3-4 inches.
Further the height of each bladder may be selected so that the bladders collapse or fold under the weight of a patient to reduce the interface pressure with the patient's skin. Further, at least some of the bladders may adapt to human morphology.
In one aspect the bladders are arrange in two or more zones. For example, the bladders may be arranged M a head and sides zone, back zone, seat zone, leg zone and foot zone. The foot and leg zones may be combined into a single zone. Similarly the back and heads and sides may be combined. The bladders may be formed by: dipping; forming one or more bladders, by any of these methods and then RF welding or heat sealing, for example, them together or to a substrate; thermal forming them from thermoelastic sheets or membranes; RF welding or heat sealing multiple panels together; or blow molding.
In one aspect, the bladders are individually injection molded and formed with a flange. The flanges are then joined together and then mounted to a base sheet, for example, by RF welding or heat sealing. The welds or heat seals may be spaced to form intermittent gaps which form passageways between each of the bladders to allow air flow between selected bladders. Tubing may also be inserted between the flanges and the base sheet to form the passageways. In this manner, the tubing management can be inside the bladders. Further, each bladder may have a thin top side, a thicker side wall or side walls, and an even thicker flange.
The bladders may be made from a variety of materials, for example, plastic resins, thermoelastic or rubberized materials, and also may be formed from two or more materials. For example, one material may form the top side and the other may form the sides and the base. In this manner, the top may have different properties than the sides. Similarly, the base may have different properties than the sides.
In one aspect, the material forming the top side is breathable, e.g. allows moisture to transfer though the material, but blocks liquid and air, such as materials that are available under the brand GORE-TEX® or GORE®.
In other aspects, one or more the bladders may have sensors at their top side. For example, the sensor or sensors may be overmolded on or in top side. For example, the sensors may include temperature sensors, humidity sensors, and also pressure sensors.
As noted above the bladders may be formed in zones. The bladders may be centralized with a group of separate side bladders or foam rails at the left and right side of the mattress, or the bladders may extend across the full width of the mattress.
In a further aspect, the support includes turning bladders under the mattress for turning one side of the mattress while the other remains generally stationary. Though it should be understood that the bladders on the stationary side may have their pressure reduced to reduce their inflation to allow the person to immerse deeper into the surface while being turned to reduce the chances of a patient fall during turning. The turning bladders may be full length bladders that may extend substantially the full length of the mattress or may be segmented. In this manner, the segment turning bladders may be independently inflated or deflated to allow access to a portion of a patient's body while being turned or to effect a rolling turning effect or just to turn a portion of the patient's body.
In another form of the invention, a patient support for supporting a patient includes an inflatable mattress, a pneumatic system for inflating the inflatable mattress, and a control system. The control system includes at least one bladder height sensor inside one of the bladders.
In one aspect, the height sensor includes an emitter and a receiver, for example, mounted on a printed circuit board provided outside the bladder, for example, on the base sheet supporting the bladders. The base sheet may be transparent or have transparent regions to allow light to pass into the bladder. Light emitted from the emitter is directed into the inside of the bladder, and optionally directed to the top side of the bladder. The reflection back is received by the receiver, which reflection is then used to determine the change in the volume of the bladder.
Alternately, the sensor may be used to measure distance or special difference. The light may be infrared and also may be supplied by another light source, such as a fiber optic cable or another light pipe. Other sensors that may be used include sensors that measure inductance. For example, an inductive sensor may include an inductive coil, which collapse under pressure and whose inductance changes as it collapses. Other sensors may measure electromagnetic coupling between one or more emitters and a receiver antenna.
To provide greater accuracy, the inside or the whole bladder with the height sensor is formed from a light material, such as white or another light color, to minimize light absorption into the bladder itself. Optionally, the inside of the bladder may have a reflective coating or layer. For example, the bladder may be formed from two layers, an inside layer with a light color (or reflective) and an outer layer that is formed from a darker color material. The two layers may be co-molded or co-formed when forming the bladder, or the outer layer may be applied post forming, such as by coating, including by spraying, dipping or the like. In this manner, the receiver will less likely to be impacted by the ambient light outside the bladder.
Where the bladder is formed from a light material (not just with a light interior) or is not totally opaque, the processor or electronics on the PCB may be configured to compensate for the ambient light outside the bladder. Therefore, the filter may be a physical layer or an electronic or signal processing filter.
In one aspect, at least each of the seat and back section zones of the mattress have at least one sensor, which are linked together. Further, the control system may use the sensors to drive the pressure to the bladders to adjust or control the pressure distribution, which can allow the pressure in the bladders to be tailored to each patient.
In another form of the invention, a patient support includes a mattress with a head end, a foot end, and two opposed sides. The mattress including at least one air operated component and a cushioning layer forming a patient support surface, and further has a recessed portion beneath the patient support surface at the foot end of the mattress. An enclosure housed in the recess and housing therein at least one pump for directing air to the air operated component and a controller for operating the pump. The enclosure having a central portion and two side portions, with each of the portions having an upper side. The side portions are located on opposed sides of the central portion and at opposed sides of the mattress at the foot end. The upper side of the central portion is recessed below the upper sides of the side portions wherein the depth of the cushioning layer at the foot end between the side portions is maintained generally constant at least along the central portion of the mattress extending from the head end to the foot end.
In one aspect, the air operated component comprises an inflatable bladder that forms at least part of the cushioning layer.
In another form of the invention, a mattress for supporting a patient includes a plurality of inflatable bladders and a control system for inflating the inflatable bladders. The control system includes one or more pumps, which are located in an enclosure or housing located in a recessed region formed in the mattress at the foot end of the mattress. The housing has a central section and two opposed side sections. The central section has a lower profile than the two side sections and further is recessed below the upper sides of the two side sections so that the central foot end of the mattress can be provided with increased thickness of compressible support and hence greater cushioning than at the sides of the foot end of the mattress, while still being able to accommodate a pump in the housing. For example, the thickness of the housing at its central section is in a range of 11⁄2 to 3 inches, 2 to 23⁄4 inches, and may be about 21⁄4 to 21⁄2 inches. The central section supports for example, the PCB for the control system of the mattress or for a control system of the bed on which the mattress is supported.
In one aspect, the pump is located in one of the side sections of the housing, while the other side section of the housing forms an enclosure for an accessory, such as a DVT cuff, a proning kit, or the like. Optionally, the housing incorporates one or more connections (power, pneumatic, and/or data) for the accessory. The connections are preferably plug-in type connections which correspond to connections on the accessory so that when the accessory is inserted into the enclosure the accessory will simply plug into the enclosure connections. In this manner when the accessory is inserted in the housing, the accessory can be connected to the power supply of the control system and optionally to the controller of the control system and further optionally to the pneumatic system of the control system. Additionally, the housing includes an access opening at the side of the housing so that the accessory can be inserted and/or removed from the housing from the side even when the housing is mounted in the mattress. Further, the housing may incorporate an access door that is also accessible so that an attendant can simply open the door and insert the accessory into the housing at the side of the mattress, which then becomes integrated with the mattress as well the control system of the mattress.
According to yet another form of the invention, a patient support for supporting a patient includes an inflatable mattress and a control system for inflating the inflatable mattress. The control system includes one or more pumps and is adapted to drive the pump or pumps at variable power.
In one aspect, the control system uses a closed-loop regulator and an integrated pump inverter, which automatically adjusts to provide constant performance whatever the AC configuration of the main power supply. The result is a universal power supply, which can accommodate 90-240v, and 50-60 Hz, which eliminates the need for a heavy transformer, and which can be used anywhere in world.
These and other objects, advantages, purposes, and features of the invention will become more apparent from the study of the following description taken in conjunction with the drawings.



DESCRIPTION OF THE FIGURES
FIG. 1 is a perspective view of one embodiment of a patient support of the present invention;
FIG. 1A is an enlarged partial fragmentary perspective view of one of the bladders on the side of the patient support of FIG. 1;
FIG. 1B is an enlarged partial fragmentary perspective view of another bladder located in the central region of the patient support of FIG. 1;
FIG. 1C is a plan view of one of the bladders of the central region with a patch of breathable material;
FIG. 1D is a perspective view of another embodiment of the bladders of a patient support of the present invention;
FIG. 2 is an exploded perspective view the patient support of FIG. 1 showing a modified bladder arrangement and base;
FIG. 3 is an exploded perspective view of the base and foam cradle of the surface of FIG. 2;
FIG. 3A is an enlarged exploded perspective view of the base and foam cradle with some details removed for clarity;
FIG. 3B is a perspective view of the control housing of the patient support of the present invention;
FIG. 3C is another perspective view of the control housing;
FIG. 3D is a top plan view of the control housing of FIG. 3B;
FIG. 3E is bottom perspective view of the control housing;
FIG. 3F is a bottom plan view of the control housing;
FIG. 3G is an elevation view of the control housing of FIG. 3B;
FIG. 3H is a right side elevation view of the control housing of FIG. 3B;
FIG. 3I is another elevation view of the control housing of FIG. 3B;
FIG. 3J is a left side elevation view of the control housing of FIG. 3B;
FIG. 4 is an enlarged partial fragmentary view of the base frame;
FIG. 5 is a schematic plan view of the layout of the control system in the patient support;
FIG. 6 is a graph of the transient force that may be applied by one or more of the bladders of the patient support;
FIG. 7 is a schematic drawing of the pneumatic control system of the control system of the patient support;
FIG. 8 is an enlarged view of the inflation portion of the pneumatic control system of FIG. 7;
FIG. 9 is an enlarged view of the percussion/vibration and turning portions of the pneumatic control system of FIG. 7;
FIG. 10A is a schematic drawing of a sensor that may be incorporated into the patient support for detecting patient immersion with the bladder shown without a patient on the surface;
FIG. 10B is similar schematic drawing to FIG. 10A but with the bladder supporting a patient who is immersed in the mattress;
FIG. 11 is a block diagram of the control system of the present invention;
FIG. 11A is a schematic drawing of the power regulator electronics for the pump;
FIG. 12 is a flowchart of the percussion therapy functions optionally provided by the control system of the present invention;
FIG. 13A-13H are screen shots of a display showing the various optional treatment protocols and may be provided by the control system of the present invention;
FIG. 14 is a perspective view of another embodiment of the bladder layer of the present invention;
FIG. 15 is a perspective view of another embodiment of the bladder layer incorporating a foam cushion at the head end of the layer;
FIG. 15A is a schematic drawing of another embodiment of the pneumatic control system of the patient support;
FIG. 16 is another embodiment of the bladder layer and foam crib layer of the patient support of the present invention incorporating foam along the sides of the bladder layer as well as at the head end and foot end sides;
FIG. 17 is another embodiment of the bladder and foam crib layer of the patient support of the present invention incorporating a foam cushion at the head end of the layer and modified side and foot end side bladders;
FIG. 18 is another embodiment of the bladder and foam crib layer of the patient support of the present invention incorporating a foam cushion at the head end of the layer and foam cushions at the foot end sides;
FIG. 19 is another embodiment of the bladder and foam crib layer similar to FIG. 16 but with the side foam section having cut outs;
FIG. 20 is a perspective view of a frame for supporting the bladder layer and foam crib of the present invention;
FIG. 21 is an enlarged view of the head end of the frame of FIG. 20;
FIG. 22 is another perspective view of the head end of the frame of FIG. 20;
FIG. 23 is a plan view of the head end of the frame of FIG. 20;
FIG. 24 is a side elevation view of the head end of the frame of FIG. 20;
FIG. 24A is a front elevation view of the head end of the frame of FIG. 20;
FIG. 25 is an enlarged view of the head end of the frame illustrating the illustrating the CPR valve and actuator cable system;
FIG. 25A is a schematic drawing of the CPR valve showing its open and closed states; and
FIG. 26 is another perspective view of the control housing illustrating the mounting brackets for the frame of FIG. 20.



DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, the numeral 10 generally designates a patient support of the present invention. While described as a “patient” support, it should be understood that “patient” is to be construed broadly to include not only people undergoing medical treatment but also invalids and other persons, such as long term care persons, who may or may not be undergoing medical treatment. As will be more fully described below, patient support 10 provides support to a patient's body and, further, may be adapted to provide therapy or treatment to the patient, for example, rotation therapy, percussion therapy, or vibration therapy or the like. Additionally, the support surface of the patient support may be adjusted to vary the immersion of a patient in the support surface, as well as provide a low air loss surface.
As best seen in FIGS. 1 and 2, support surface 10 includes a base 12, a foam cradle or crib 14, and a bladder layer 16 formed from a plurality of bladders 18, all optionally enclosed in a cover 19. A suitable cover may be formed from a moisture vapor permeable, but liquid impermeable material, such as GORE® Medical Fabric, available from W. L. Gore & Associates, Inc., of Elkton, Md. to facilitate moisture management of the patient. Cover 19 may also include indicia to indicate proper positioning for the patient on the mattress. For example, cover 19 may have printed thereon or woven therein a design or image, such as a representation of a patient's lung, which is positioned to align over the treatment bladders (e.g. percussion/vibration bladders described below) so that if mattress 10 is used to apply percussion or vibration treatment to a patient, a caregiver can position the patient on the mattress so that the patient's lungs are properly aligned with the indicia and thereby properly align the patient's lungs with the percussion/vibration bladders described below. Cover 19 may also have other indicia, such as prints on the side, to position other portions of the body, including the neck and/or shoulder position. The cover may also have a side accessible pocket formed under its top sheet, which is formed by stronger material, such as Kevlar, which allows an X-ray cassette to be inserted under patient below the cover.
As will be more fully described below, bladders 18 provide support to a patient's body and also optionally provide one or more of the therapies noted above. In this manner, the same layer 16 may provide both support to a patient and also, optionally, provide therapy to a patient. Further, bladders 18 can apply the treatment just below the patient's tissue with the therapy forces effectively only separated from the patient's skin by the cover and the sheets.
Referring again to FIG. 1, layer 16 includes a plurality of bladders 18 that may be arranged in several groups. In the illustrated embodiment, layer includes three groups of bladders. A first group 20 of bladders is arranged to extend along the opposed sides 22, 24 of surface 10 and across the head end 26 of surface 10 to form a generally inverted U-shaped arrangement, with two or more rows of bladders at each of the sides and at the head end. Though as will be described below in reference to FIGS. 14-19, the bladders on the sides and at the head end may be eliminated and replaced with foam or other bladder arrangements. Further, the number of bladders may be increased or decreased. For example, additional rows may be provided at the head end, such as shown in FIG. 2.
A second group 28 of bladders is located between the sides of the bladders of the first group, which extend from the first group at the head end 26 to the foot end 30 of surface 10 and provide the primary support bladders for the patient. The bladders 18a of the first group 20 of bladders have a generally rectangular box-shaped configuration, while bladders 18b of second group 28 may be rounded or have more than four sides. For example, bladders 18 may have a hexagonal box-shape, so that the bladders can be nested to reduce the creation of continuous edges that span the width or length of layer 16, which could be felt by a patient, as will be more fully described below. In addition, a third group 32 of bladders within the second group 28 of bladders may be arranged in a central portion of the second group of bladders at the chest area of a patient, which third group 32 of bladders may be used to apply one or more therapies to the patient, Third group 32 may be arranged in two groups, for example, two groups of 3 bladders, which form a top zone, middle zone, and bottom zone for each lung, with one group for apply treatment to patient's left lung and the other group for applying treatment to the patient's right lung. Each of these bladders may be individually controlled.
Bladders 18 are formed from upper and lower polymer sheets or, elastomeric sheets, with the upper sheet being molded into the configuration as shown in FIG. 1. For example, a suitable polymer sheet includes sheets formed from thermal polyurethane (TPU). The upper sheet is optionally molded into the box-shaped bodies using injection molding, though vacuum molding may also be used. Bladders 18 may be formed in groups or each of the bladders may be individually molded and welded together (heat sealing or RF) to form the upper sheet. As best seen in FIG. 1, bladders 18 are molded into their respective box-shapes in the upper sheet, which is heat welded to the lower base sheet in a manner more fully described below. Optionally, bladders 18b, 18c each have a height to width ratio of greater than 1:1 so that they are taller than they are wide. Further, the height to width ratio may be in a range of 1:1.5 to 1:4 or in a range of 1:2 to 1:3, which height will allow bladders 18 to provide a great range of immersion when supporting a patient. Bladders 18a may be shorter and have a 1:1 height to width ratio.
As best seen in FIGS. 1A and 1B, each of the bladders 18 (18a, 18b, and 18c) has an upper wall 34, which forms a patient facing surface or side 36 and a perimeter wall 38, which may be formed from one or more sidewalls 38a. In the illustrated embodiment, as noted, side bladders 18a have a rectangular box shape with four sidewalls 38a, and four edges 36a at patient facing surface 36 while bladders 18b, 18c have a hexagonal box shape with six sidewalls 38a and six edges 36a at the patient facing surface 36. By providing more than four sides, such as the illustrated hexagonal-shaped cross-sections, bladders 18b and 18c may be nested in a manner so that the edges of the respective bladders do not align to form a continuous straight edge and instead are offset from each other, which reduces the patient's detection of the edges of the bladders and, therefore provides increased comfort to a patient. In addition, a patient may not feel a gap between the bladders because the gaps span only short distance under the patient's body.
In another embodiment shown in FIG. 1D, 118b, 118c bladders have a hexagonal box shape, but with six concave sidewalls 138a and six curved edges 136a at the patient facing surface 136. The degree of curve may be varied and further may be infinite so that the side edges 136a are generally straight. Further, in this embodiment, the top side of the bladder is formed by a patch or panel 136b of breathable material, such as moisture permeable but gas impermeable or moisture permeable gas impermeable and liquid impermeable material, such as GORE-TEX® or GORE®Medical Fabric. In this manner, the top side of the bladders retains the gas in the bladder but allows moisture to flow into and out of the pods, but does not allow liquid, such as bodily fluids to flow into the bladders. In this manner, moisture may be drawn into some of the bladders, while the other bladders help carry the moisture away and further under the influence of the air flow through the surface pushes moisture out from other bladders away from where the patient is lying.
The patches may be adhered to the sides of the bladder during the molding process and may be flush with the top of the sides or may even extend over the sides. In the illustrated embodiment, the patches are recessed below the tops of the bladder's side walls to minimize the detection of the patch. For further details about the forming of the bladders reference is made to the following descriptions. Further, while illustrated in reference to a bladder with hexagon shaped top side, the fabric panels may be incorporated into other shaped bladders, including rounded bladders.
The mold apparatus forming the bladders may include two or more mold plates, which include a plurality of gates for each mold cavity (for each bladder) and, further, include a plurality of channels that extend radially outward from the central region of each cavity to facilitate the flow of the material forming the bladders across the width of the mold cavity for each bladder, which therefore facilitates the control over the wall thickness of the respective bladders. Additionally, to facilitate the release of the sheet from the mold cavities after molding, the mold plates may be sandblasted before use so that the respective mold faces of the mold plates have a “roughened” surface or may be coated with a release material, such as TEFLON, which allows better inflow of air between the sheet and the mold faces when the sheet is being removed from the mold cavity.
The bladders may be formed by: dipping; forming one or more bladders, by any of these methods and then RF welding or heat sealing, for example, them together or to a substrate; thermal forming them from themmoelastic sheets or membranes; RF welding or heat sealing multiple panels together; or blow molding.
In another method, the bladders are individually injection molded and formed with a flange. The flanges are then joined together to form a layer of the bladder layer and then mounted to a base sheet, for example, by RF welding or heat sealing. The welds or heat seals may be spaced to form intermittent gaps which form passageways between each of the bladders to allow air flow between selected bladders. Tubing may also be inserted between the flanges and the base sheet to form the passageways. In this manner, the tubing management can be inside the bladders. Further, each bladder may have a thin top side, a thicker side wall or side walls, and an even thicker flange.
The bladders may be made from a variety of materials, for example, plastic resins, thermoelastic or rubberized materials, and also may be formed from two or more materials. For example, one material may form the top side and the other may form the sides and the base. In this manner, the top may have different properties than the sides. Similarly, the base may have different properties than the sides.
While reference hereafter is made to bladders 18b and 18c of the first embodiment, it should be understood that many of the details described herein may apply to any of the bladders. The height of each support bladder 18b, 18c may be in a range of approximately 4-10 inches, 5-9 inches, or 6-8 inches, and may be about 6 inches, while the maximum width of each bladder may be in the range of 3 to 4 inches. Thought it should be understood that some of the side bladders may be shorter and further may not have the same ratio as the central bladders that form the bulk of the patient support surface. For example, the height of the bladders under the body may be 6 inches, and 3 inches under the arms and head. But generally, the height (H) of at least the central group of the bladders is greater than their respective widths (W) and further as noted optionally such that H>2W.
Further, the thickness of the perimeter walls and regions surrounding the central portion of each bladder may be in a range of 0.01′′ to 1.175′′, while the thickness of the central region may be in a range of 0.01′′ to 0.035′′. Thus when air flows into the bladders 18c under high pressure, for example, in a range of 3 to 9 psig, over a short period of time transient forces can be generated at the patient facing surface of bladders 18c that are of sufficient magnitude to generate either vibration or percussion treatment. For example, referring to FIG. 1C, when airflow into bladders 18c is provided in this range, a transient force profile P1 can be generated at a patient facing surface 36 of bladder 18c, which achieves a greater level of force over a shorter period of time than a conventional percussion or vibration bladder, which typically generate a force profile P2. With an increased force over a shorter period of time, a more effective vibration or percussion therapy may be achieved than heretofore known using bladders 18. Additionally, with the support layer of the present invention also providing the therapy layer, these transient forces are generated at the surface of the support layer unlike the prior art mattresses. Further, as noted, these forces then are only effectively separated from the patient's skin by the cover.
As noted above, bladders 18 may be formed between two sheets—by an upper sheet that is molded into the desired shape and the lower sheet, which forms a base into which the upper sheet is then heat welded or RF welded to thereby form the chambers of each bladder between the upper sheet and the lower sheet. The welds are extended between each of the box-shaped bodies but are terminated over discrete regions adjacent each of the bladder sides such as described in U.S. provisional application Ser. No. 61/138,354, filed Dec. 17, 2008, entitled PATIENT SUPPORT SURFACE, which is commonly owned by Stryker Corporation, and which is incorporated in its entirety by reference herein. In this manner, passageways between the adjacent bladders are formed so that air can be delivered through a network of passageways formed in the bladder layer 16, which are in fluid communication with one or more inlets provided at the perimeter of the bladder layer 16. Furthermore, with this construction, some bladders may be isolated from other bladders so that they remain inflated even when other bladders have their pressure adjusted, for example to accommodate pressure redistribution. For example, the side bladders may remain inflated at generally constant pressure while the interior bladders may have their pressure adjusted independently of the side bladders.
To that end, each group of bladders, such as groups 18a and 18b, may have its own network of passageways with its own respective inlet or inlets so that each group may be independently inflated and controlled. Further, bladders 18c in the third group 32 of bladders may each have their own inlet, such as provided at the underside of bladder layer 16 so that each of the bladders (18c) may be individually controlled and, as noted be filled with air with a high pressure line so that they have a different pressure of air delivered to the respective bladder so that bladders 18c can be independently controlled and more over generate a transient force its facing surface. Thus, each bladder 18c may generate a transient force at its patient facing surface, which transient force may be used, as noted, to apply vibration or percussion therapy to a patient supported on surface 10. In addition, since each of the bladders 18c may be individually controlled, the pressure in the respective bladders may be applied sequentially to bladders 18c to create a rolling effect up (from foot to head) one side or both sides of the group of bladders or only a selected region or regions of the lungs may have a treatment applied. For percussion therapy, the frequency of the transient force may be in a range of 4 to 8 Hertz. In addition, the pressure in bladders 18a and 18b (and 18c) may be controlled so that bladders 18a are more pressurized for example than bladders 18b (and 18c) to provide firmer support of the perimeter of the mattress.
Crib 14 has side walls 14a that extend along sides 22 and 24 of mattress 10 and across head end 26, and which extends upwardly from base wall 14b to thereby form an upwardly facing recess 14d. Extending from side walls 14a are perimeter walls 14c, which extend across the head end 26 and extend from the head end 26 to the foot end 30. The perimeter wall is therefore raised above the bottom wall. Additionally, the perimeter wall may have regions 14e of increased thickness to provide increased firmness at the egress/ingress locations at the sides of the mattress. The foot end of base wall 14b, however, may terminate before the side walls 14a so as to form a recess for a foot end enclosure described more fully below.
As best understood from FIG. 1, bladders 18b and 18c extend into recess 14d, and bladders 18a are positioned over the perimeter walls 14c so that the bladders 18a have reduced overall height than bladders 18b, 18c but, as noted, are more pressurized so that the sides of the mattress have increased firmness at the opposed edges of the mattress. This increased firmness may be advantageous and provide greater stability when a patient is entering or leaving the bed, and also may minimize the detection of the base. With the patient on, the bed, the pressure in bladders 18a is less that the pressure in bladders 18b and 18c and, therefore, bladders 18b, 18c will tend to be compressed below bladders 18a. Therefore, as will be more fully described below, the bladders may have the same height and still achieve the cradling effect of the taller side bladders due to the immersion of the patient into bladders 18b, 18c. 
Additionally, bladders 18b may be segregated into a plurality of sub-groups or zones, such as a head end zone, a chest zone, an abdominal zone, a leg zone, and a foot zone, with each zone having its own network of passageways so that pressure in each zone may be adjusted to suit a particular patient's need. Because each bladder in each sub-group of bladders is in fluid communication with each of its adjacent bladders, and each of the adjacent bladders are in fluid communication with their adjacent bladders, the pressure induced by a person laying on the bladders does not significant raise the pressure in the adjacent bladders surrounding the compressed bladders. Instead, the pressure is redistributed so that the pressure applied to the patient is not only applied by the bladders under the patient but also by the surrounding bladders. This reduces, if not eliminates, high pressure points on the patient's body and moreover allows better immersion of the patient into the surface. With the redistribution of pressure to the bladders beyond the bladders immediately surrounding the patient's footprint (bodyprint), the bladders immediately surrounding the patient's footprint effectively cradle the patients' body thus increasing the contact surface area between the patient's body and the mattress. Thus, reduced pressure points and better immersion are both achieved. In addition, as will be more fully described in reference to the control system, the pressure in a selected sub-group or sub-groups of bladders 18b may be adjusted to adjust the degree of immersion of the patient into the surface, which is more fully described below in reference to the control system. For example, for a patient who is more active, it may be preferable to provide less immersion than for a patient who is less active or inactive.
To facilitate moisture management and/or improve breathability of mattress 10, patient facing surfaces 36 of at least some of the bladders 18 may include a patch of gas permeable material or liquid impermeable and gas permeable material, such as GORE-TEX® or GORE® Medical Fabric on the top side of the bladder. For example, referring to FIG. 1C, one or more bladders 18 (and optionally each bladder) may include a patch 36b of gas permeable or gas permeable and liquid impermeable material, as noted such as GORE-TEX® or GORE®Medical Fabric adhered to its patient facing side surface 36, for example by an adhesive. Alternately, the patches may be adhered during the molding process. Patches 36b may be mounted onto the patient facing side or alternately recessed into a recess formed in the patient facing side of the bladders to minimize the detection of the edge of the patch. With use of the patches, the protective layer formed by the patches is flexible and, moreover, will not restrict the bladder's movement—in other words, the patches leave the bladders unrestrained and do not interfere with the immersion of the patient into the mattress.
Additionally, referring again to FIG. 1A, any of the bladders 18 may incorporate therein a foam insert 42, which may only partially fill chambers 44 of the bladders to provide additional support and padding in the event that pressure in the bladders is lost or just low or the patient weight is above average so that the patient will not detect the presence of the mattress frame, more fully described below. Further, turn bladders 18d (FIG. 9) may be provided either beneath bladders 18b or in between bladders 18b and are located along the sides of the mattress, which may be independently inflated to provide turn therapy to the patient. For example, when the pressure in the turning bladders is increased, the pressure in the surrounding or overlaying bladders may be reduced to lower the rotational axis of the patient and thereby provide greater stability to the patient when being turned. Additionally, because the bladders that provide treatment may be individually controlled, vibration and/or percussion may be applied at the same time as rotation treatment. Further, the treatment protocol may be varied to suite particular needs of a patient.
To direct the air to the various bladders, mattress 10 includes a pneumatic control system 45 (FIGS. 7-9), which delivers air to and optional releases air from the respective bladders as more fully described below. Optionally, to reduce the tubing associated with prior art bladder-based mattresses, mattress 10 incorporates fluid passageways into its support structure, which, therefore, allow the mattress support structure to provide dual functions—namely, to support a patient and to direct air to the various bladders and optionally to a low air loss system.
Referring to FIGS. 3 and 3A, base 12 includes a base frame 46 and a perimeter frame 48, which has incorporated therein conduits for directing the flow of air through the base from various valve assemblies and pumps described more fully below. Frame 48 is formed from a pair of side frame members 50, and transverse members in the form of side enclosures 54 and a head end enclosure or housing 56 and a foot end enclosure assembly or housing 58. Enclosures 54, 56, side frame members 50, and enclosure assembly 58 are connected so that they form frame 48, with side frame members 50 incorporating one or more flexible joints or hinges 62 so that frame 48 can be articulated about one or more axes. For example, one of the joints may be located between the head end and the medial, torso portion of the frame and another joint may be provided between the foot end and the medial torso portion. It should be understood that the number and location of flexible joints may be varied.
Referring again to FIGS. 3 and 4, frame 48 is supported on frame 46, which is formed from foam and is reinforced by metal or plastic plates. Frame 46 includes a head end cover 56a and a foot end cover 58a for receiving head end enclosure 54 and foot end enclosure assembly 58, respectively. Covers 56a and 58a are interconnected by transverse side covers 57a, which extend over side frame member 50. Covers 56a, 58a, and 57a provide a cushioning layer over frame 48 and further provide a protective barrier to the various valves and electronics housed in enclosure 54, 56, and in enclosure assembly 58. Cable managers 57 are supported by part 57a, which allow the cables/wires, to be grouped and directed through the mattress.
As will be more fully described below, enclosure assembly 58 includes one or more compartments for housing components (e.g. the pumps/compressors/blowers/controls/modules, valves, etc). For example, in the illustrated embodiment, enclosure assembly 58 includes one or more compartments for housing components of pneumatic system 45 and further optionally has one or more bays with connectors, both communication and power connectors, which are in communication with the mattress controller 70 and its power supply, to allow additional components (e.g. modules or accessories) to be mounted in enclosure assembly 58 and pneumatically and electrically coupled to and in communication with controller 70. Enclosure assembly 58 is optionally made from a rigid material, such as metal, including aluminum, or made be made from a polymeric material, such as plastic.
For example, as best seen in FIG. 3, enclosure assembly 58 may include two ore more bay modules 59a and 59b for receiving additional components. For example, additional components may include a control board for controlling and supplying air to a DVT cuff or to a hyperbaric device or supplying a suction line to a negative pressure wound treatment device, or to a low air loss system. To allow easy access to bay modules, cover 58a may include one or more openings 58b so that the component can be simply plugged into the mattress so that these devices can be controlled and operated by the mattress controller and also the bed based main control board noted below. In this manner, an attendant may remove or add accessories through the side of the mattress by simply plugging in or unplugging an accessory, such as an accessory module.
Referring to FIGS. 3B-3J, foot end enclosure assembly or housing 58 has a central section 58c and two opposed side sections 58d, 58e, which house the pump and the bay modules 59a and 59b. The central section has a lower profile than the two side sections and further has its upper side recessed below the upper sides of the two side sections so that the central foot end of the mattress can provide increased thickness of compressible support and hence greater cushioning than at the sides of the foot end of the mattress while still being able to accommodate a pump in the housing. For example, the thickness of the housing at its central section may be in a range of 11⁄2 to 3 inches, 2 to 23⁄4 inches, and may be about 21⁄4 to 21⁄2 inches. The central section supports, for example, the PCB for the control system of the mattress, while the side sections as described above house the pump and bay modules. In this manner, when the enclosure assembly 58 is located at the foot end of the mattress and in the recess formed by the foam crib, the cushioning layer formed by bladders 18b may maintain its full height or depth through to the foot end of the mattress.
Side frame members 50 and side enclosures 54 include one or more conduits for directing the flow of air through the base from the respective valve assemblies 60, which are located at enclosures 54 and 56 around the perimeter of base 12, and for exhausting air from the bladders through a CPR pressure regulator valve 78. Each side frame member 50 may have a plurality of conduits 50a and 50b formed therein, for example, forming a pressurizing line for inflating bladders 18a and 18b through valves 60, for delivering pressurized air to bladders 18c and for exhausting air from bladders 18b and 18c to administer CPR, more fully described below. Further, the flow of air to and conduits 50a and 50b may be controlled by valves, such as check inlet valves and electrically operated outlet valves so that one or both conduits 50a and 50b may form a reservoir, optionally, a pressurized reservoir, that can be used to store pressurized air in the surface for selective use, for example, to apply percussion or vibration treatment, as well as to inflate the bladders as needed to maintain the proper pressure in the bladders. For example, the pressure in the reservoir may be in a range of 0 psig to 15 psig, 2 psig to 15 psig, 2 psig to 12 psig, or 4 psig to 9 psig, including around 4.5 psig. To control the release of the pressurized air, the electrically controlled outlet valves are in communication with the mattress controller (70, described below), which controls actuation of the valves. Optionally, the outlet valve is a fast response valve to let bursts of air into the mattress. As a result, the mattress can be filled quickly and further selectively inflated with a pressure to deliver percussion or vibration with the same air supply. To reduce the turbulence in the pneumatic system, inserts may be provided, for example, in the outlet valve or the reservoir's inlet. For example, the insert may be formed from a porous material, such as filter material, which can be used anywhere in pneumatic system to reduce turbulence and hence noise.
For example, side frame members 50 may be formed, such as by molding, for example from a plastic material, such as a polymer, with the conduits optimally formed therein during molding. In the illustrated embodiment, members 50 are hollow members with internal webs that form closed passageways 64 (see FIG. 4) that form the conduits (50a and 50b) for directing air through members 50. Alternatively, the conduits may be formed from tubular members, including metal, such as aluminum tubular members, that are molded, such as by insert molding, into members 50. These too can be configured to form reservoirs.
Enclosures 54 and 56 are, for example, formed from a rigid material, such as plastic or a metal, including aluminum. Both may include extrusions and further also include conduits 54a, 54b, and 56a, 56b, 56c (FIG. 4), such as rigid conduits, either formed therein in the extrusions or mounted thereto so that the conduits may also form part of the frame, with conduits 54a and 56a forming pressurizing lines for inflation, and conduits 54b, 56b forming exhaust conduits.
As best seen in FIG. 4, the respective conduits 50a, 50b, 54a, 54b, 56a, and 56b are in fluid communication with each other through couplers 66 and 68 that provide sealed connections between the respective conduits. Coupler 68 may be inset molded with member 50 when forming member 50 or may be post attached. The flow of air through conduits 50b, 54b, and 56b (pressurizing lines) to the respective percussion/vibration bladders (18c) is controlled by electrically operated valves 60, such as solenoid valves, and further two position check valves, and may comprise large orifice valves, which as noted above are located at and mounted to enclosures 54 and 56.
Referring to FIG. 3A, each enclosure 54 houses one or more valves 60 for controlling the inflation and deflation of various sub-groups or zones of bladders, e.g. the head zone, the torso zone, the leg zone, and the foot zone, through conduits 50b, 54b, or 56b with one valve for each, zone or sub-group. Further, as noted, conduits 50a, 54a and 56a are used to exhaust air from the respective bladders. Air is typically delivered to bladders 18a and 18b in a pressure range of about 0.05 to 2 psig, with the exception of a maximum inflate condition, which occurs typically after a CPR event and at a higher pressure to quickly return the bladders to their normal inflated state. Referring again to FIG. 4, enclosure 54 at the head end (which is at the head end of the frame) houses a bladder inflation valve 60a, which controls the inflation of bladders 18a and 18b and, more specifically, the head end group of bladders 18a and 18b. In the illustrated embodiment, enclosure 54 at the head end left side of the frame may also include a valve 60b for controlling the inflation and deflation left side turn bladder 18d (FIG. 9), with an enclosure 54 on the right side of the mattress housing a valve 60b for controlling the inflation and deflation right side turn bladder 18d. Similarly, the foot end enclosures 54 enclose the valves 60a for controlling the foot end bladders. In addition to housing valves 60a, 60b, the enclosures 54 may also enclose and provide mounting locations for local control boards 65d, 65e, 65f, 65g, and 65h (FIG. 5) (I/O cards), which are in communication with and powered by a main controller 70 and the main controller power supply (FIG. 11), Controller 70 is a micro-processor based controller, with one or more processors, a power supply, and one or more memory devices.
Mattress 10 may also include back-up battery power for when mattress 10 is unplugged from a bed based control and power supply (described below), which allows controller 70 to monitor pressure in bladders 18 to see if there is a leak and generates warning when pressure is too low, which provides a means to assure that control system is plugged in or to detect when surface is leaking. Controller 70 along with the pumps/compressors of the pneumatic system are also optionally located in enclosure assembly 58 located at the foot end of the mattress 10.
Referring to FIG. 11A, controller 70 uses a closed-loop regulator and an integrated pump inverter 71, which includes a rectifier 71a and an inverter 71b to automatically adjust to provide constant performance whatever the AC configuration of the main power supply (off the bed). The result is a universal power supply, which can accommodate 90-240v, and 50-60 Hz, which eliminate the need for a heavy transformer, and which can be used anywhere in world.
To deliver air to the various bladders, the valves may be coupled to the respective inlets of layer 16 via conventional tubing. As it would be understood, the valves to control the bladders may therefore be advantageously located so that the distance between the respective valves and bladders they control is minimized. In this manner, the amount of tubing to inflate the various bladders may be significantly reduced over prior art inflatable mattress surfaces and, moreover, may all be contained and enclosed in the surface.
Referring again to FIG. 4, enclosure 56 optionally supports a plurality of valves 60c for controlling the flow of air to bladders 18c used for vibration or percussion therapy, which deliver air at a higher pressure, for example, at 3 to 9 psig though it could be as high as 15 psig. For example, the pressure in the reservoir may be in a range of 0 psig to 15 psig, 2 psig to 15 psig, 2 psig to 12 psig, or 4 psig to 9 psig, including around 4.5 psig.
Similar to valves 60a, valves 60c comprise electrically operated valves, such as solenoid valves, and also may comprise large orifice valves. Optionally, valves 60e are fast response valve to let bursts of air into the mattress. Valves 60c are in fluid communication with conduits 56b and 56c and are controlled by control boards 65a, 65b, and 65c mounted in enclosure 56, which are in two-way communication with controller 70 and are powered by the controller power supply.
To supply air to conduits 50b, 54b, and 56b, as noted pneumatic system 45 includes one or more air delivery devices, namely compressors or pumps 72 (FIG. 3A), such as 120 volt pumps. Optionally, two (such as shown in FIGS. 7 and 8) or three (such as shown in FIGS. 5 and 11) or more pumps 72a, 72b, and 72c may be provided, with pump 72a providing airflow to conduit 50b for bladder inflation or turn therapy, and pumps 72b and 72c, which are connected in series with each but in parallel with pump 72a, providing airflow to conduits 50b, 54b, and 56b for percussion/vibration, which require a greater flow of air than bladder inflation and adjustment. In this manner, one, two, or three of the pumps may be used, which allows for smaller pumps to be employed and thereby reduce the noise and vibration and also heat generated by the respective pumps. Additionally, the output of each pump may be directed into the air delivery system through canisters 73a, 73b, and 73c to further reduce noise, such as described in U.S. patent application Ser. No. 11/939,829, filed Nov. 14, 2007, and commonly owned by Stryker, which is incorporated in its entirety by reference herein.
Further, as illustrated in FIG. 15A in reference to the embodiments described below, where noise reduction is desired, an even number (2N, where N is an integer) of pumps may be used in 180° phase to cancel vibration. For example, one of the pumps may have its electrical connection reversed from the other pump. Alternately, N number of pumps may be used in combination with N number of actuators having the same or substantially the same inertia, stroke, etc as the pump or pumps to counter balance vibration of pump or pumps.
In addition to inflating bladders 18a, 18b, 18c, and 18d, one or more of the pumps may be used to direct air to a low air loss system 75 (FIG. 11). For example, the low air loss system may include perforated tubing positioned between some of the bladders so as to direct air flow across or between the bladders, which air flow would facilitate the removal of moisture from the patient's skin. Further, tubing or tube extensions or perforated bladders may be provided to extend up between the support bladders to direct air close to the support surface. Alternately, air-loss conduits may be formed in the bladder layer, for example, the base sheet between the support bladders.
To control the flow of airflow from pumps 72a, 72b, and 72c to the low air loss system (LAL), pneumatic system 45 includes valves 74a, such as solenoid valves, which are controlled by main controller 70. Additionally, the control system includes valves 74b, which direct air to check valves 76a, 76b, which in turn direct the flow of air to quickly inflate bladders 18a, 18b, 18c to do a max inflate CPR. Alternatively, CPR plugs 78a and 78b, which allow manual opening of the pressure line so that all the bladders can be quickly deflated so at least the chest area of the patient can rest on the flat hard surface of the deck of the bed and allow a caretaker to administer CPR to the patient. In addition, as noted above, air from the CPR supply line may be exhausted through a CPR pressure regulator valve 78 (FIG. 11), which is powered and in communication with controller 70 so that the reset of the valve after a manual activation may also be controller by controller 70. After CPR is administered the bladders 18 can then be inflated quickly through valves 74b or a CPR max inflate valve 77, which provides a maximum inflate function after the bladders have been deflated to restore quickly the support surface to its inflated state. As will be more fully described below, a single CPR valve may be used instead, also with an optional auto reset feature.
As noted above, valves 60c deliver airflow to bladders 18c at a pressure sufficient to generate transient forces at the respective patient facing surfaces. For example the pressure, as noted typically would fall in a range of 3 to 9 psi, but be as high as 15 psg. Each valve 60c may be independently controlled so that the vibration or percussion therapy may be applied using one or more of the bladders alone or in combination with the other bladders and, further, in any desired sequence. In addition, pneumatic system 45 may include a diverter valve 60d, which can divert the exhaust air from the bladders 18c to bladders 18b and 18a (FIG. 7) to avoid over pressurization of bladders 18c. 
Optionally, when inflated, bladders 18b and 18c are inflated to a volume that is less than their full volume so that the bladders are in an un-stretched state when inflated. Further, when the bladders are operated and the pressure in the bladders falls below a preselected threshold value, the pressure in the bladders is increased but the volume is still maintained below the full volume of the bladders. When air is directed to bladders 18c to apply percussion or vibration, the volume of the bladders may still maintained below their full volume to thereby reduce fatigue in the material forming the bladders.
As previously described, one or more bladders on each side of the surface 10 may be inflated to provide turn therapy. Turn bladders 18d, as noted, may be located under bladders 18b and 18c and are inflated by valve assemblies 60b, which as noted may be located in enclosures 54 and controlled by local control boards 65a and 65b (FIG. 5). Valves 60b may also be located at head end enclosure 56. In use, the turning bladders are used for turning one side of the mattress while the other remains generally stationary. Though it should be understood that the bladders on the stationary side may have their pressure reduced to reduce their inflation to allow the person to immerse deeper into the surface while being turned to reduce the chances of a patient fall during turning. The turning bladders may be full length bladders that may extend substantially the full length of the mattress or may be segmented. Further, the segment turning bladders may be independently inflated or deflated to allow access to a portion of a patient's body while being turned or to effect a rolling turning effect or just to turn a portion of the patient's body. For examples of optional controls for and examples of suitable turning bladders, reference is made to U.S. application Ser. No. 12/234,818, filed Sep. 22, 2008, entitled RESILIENT MATERIAL/AIR BLADDER SYSTEM; and U.S. application Ser. No. 11/891,451, filed Aug. 10, 2007, entitled TURN-ASSIST WITH ACCESS AREAS, which are incorporated herein by reference in their entireties.
Each of the valves noted herein are in fluid communication with the respective bladders via flexible tubing sections 80 (FIG. 7). As described previously, the bladders 18 are formed between two sheets of material with a network of passageways formed between the two sheets so that the inlets to bladders 18a and 18b may be located around the periphery of the bladder layer 16. As noted previously, the inlets to bladders 18c may be located at the underside of layer 16 so that the tubing to inflate the percussion vibration therapy bladders (bladders 18c) extends under layer 16 to connect to bladders 18c. Turning bladders 18d may also similarly include inlets at their underside or at their periphery so that the tubing for inflating bladders 18d also extends under layer 16. In this manner, at least valve assemblies 60a can be located in close proximity to the inlets of their respective bladders, which as noted can minimize the amount of tubing needed in the surface.
In addition to controlling the pressure in the bladders, controller 70 is also adapted to regulate the pressure in the respective bladders 18 via valve assemblies 60a, 60b, and valves 60c, and 60d, which are in fluid communication with the air supply side of the pneumatic system but exhaust air when the pressure in the respective bladders exceeds a predetermined maximum pressure value. As noted above, it may be desirable to control the inflation of the bladders so that they are not stretched and instead are inflated between two volumes that are less that the maximum volume of each bladder (unstretched maximum). As a result, the mattress can be filled quickly and managed (pressure and immersion (see below)) and also able to deliver percussion or vibration with the same air supply.
Additionally, controller 70 may also include an immersion control system 84 (FIG. 5). Immersion control system 84 includes one or more sensors 86, which sense the immersion of a patient into the bladders 18 and generates a signal to the main controller 70. Based on the signals from sensor(s) 86, the main controller will adjust the pressure in the respective bladders 18 so that the immersion is adjusted to a pre-determined magnitude or to a selected magnitude, as will be more fully described below in reference to the operation of the controller and display.
Referring to FIG. 10, each sensor 86 may comprise an optical sensor assembly 88. In the illustrated embodiment, each optical sensor assembly 88 may be located in or below a bladder 18. For example, when the sensor assembly is located below the bladders, the base sheet may have a transparent portion to allow light to pass through. Assembly 88 includes a light transmitter or transmitting device 90, such as an LED, and a light receiver or receiving device 92, such as a light sensor, which are powered by and in communication to main controller 70 via circuit board 87, which may be located in enclosure 54. To determine the immersion of a patient, main controller 70 powers light transmitter 90 and receives signals from device 92 from the reflection back, which signals are converted and then compared to stored values in the memory device of the controller. When light is transmitted from light transmitter 90, the light is projected upwardly (90a) toward the underside of the patient facing surface of the bladder. Receiver 92 then detects the reflection of the light and generates a signal, which is a function of the intensity of the reflected light. The light intensity of the reflected light increases as the bladder is compressed, which increase in intensity is detected by receiver 92. Using the signals from receiver 92, main controller 70 is then able to determine the degree of immersion of a patient into the surface. As noted, controller 70 determines the degree of immersion from the signals it receives from device 92 and then compares it to a stored value, such as a stored maximum and/or minimum immersion value, which is stored in the memory device of the main controller (for that region or group of bladders) to determine whether the pressure in the respective bladder or bladders needs to be adjusted. The memory device of the controller may have different values for different region of the mattress, and further these values may be adjusted, as noted below. If the pressure is too low, controller 70 adjusts the respective valve to direct air flow to the respective bladder or bladders in the region where the immersion is found to exceed the maximum immersion for that region. Similarly, if the immersion is less than the minimum immersion for that region, controller 70 will actuate the respective valves to vent air in the respective bladders. In this manner, the degree of immersion may be used to manage pressure on the patient's skin. Further, an immersion map may be generated and displayed (for example at display 98 discussed below) using software stored in controller 70 in mattress 10 or in a main control (for example control 96 discussed below) in a bed on which mattress 10 is supported, which could be used as a pressure map. Additionally, as noted below, the degree of immersion can be adjusted. For example, the pressure behind the legs of a patient may be increased while decreasing the pressure on the heels of a patient, to reduce the likelihood of sores.
Optionally, optical sensor assembly 88 may include a channel 94 to allow light to be transmitted directly to a second receiver 93 so that the intensity of the light emitted by light emitter 80 remains constant whatever the operating conditions, which allows the system 88 to adjust itself to compensate for any decay in light emitted from light transmitter 90.
As noted above, optical sensor assembly 88 may be located inside the bladder or outside the bladder, when the bladder is formed from a translucent or transparent material. In this manner, for example, the optical sensor assemblies may be arranged in an array on a common substrate beneath the bladder layer 16. As noted, light is emitted into the inside of the bladder, and optionally directed to the top side of the bladder. The reflection back is received by the receiver, which reflection may then used to determine the change in the volume of the bladder, though the sensor could alternately be used to measure distance or special difference. The light may be infrared (such as by way of an infrared LED) and also may be supplied by another light source, such as a fiber optic cable or another light pipe. Other sensors that may be used measure inductance. For example, an inductive sensor may include an inductive coil, which collapse under pressure and whose inductance changes as it collapses. Other sensors may measure electromagnetic coupling between one or more emitters and a receiver antenna.
To provide greater accuracy, the inside or the whole bladder (with the sensor assembly) is formed from a light material, such as white or another light color, to minimize light absorption into the bladder itself. Optionally, the inside of the bladder may have a reflective coating or layer. For example, the bladder may be formed from two layers, an inside layer with a light color (or reflective) and an outer layer that is formed from a darker color material. The two layers may be co-molded or co-formed when forming the bladder, or the outer layer may be applied post forming, such as by coating, including by spraying, dipping or the like. In this manner, the receiver will less likely to be impacted by the ambient light outside the bladder.
Where the bladder is formed from a light material (not just with a light interior) or is not totally opaque, the processor or electronics on the PCB may be configured to compensate for the ambient light outside the bladder. Therefore, the filter may be a physical layer or an electronic or signal processing filter.
Each of the seat and back section zones of the mattress may have at least one sensor, which are linked together. Further, as noted, the control system may use the sensors to drive the pressure to the bladders to adjust or control the pressure distribution, which can allow the pressure in the bladders to be tailored to each patient.
Alternately, as noted, a pressure sensitive sensor may be used to detect the immersion of a patient into mattress 10. For example, a suitable pressure sensor may include a thin membrane that changes capacitance or resistance in response to pressure, which again is in communication with the controller 70, which then determines the immersion based on the capacitance or resistance and compares the immersion to stored maximums and/or minimum values for the desired immersion. In addition, one or more the bladders may have other sensors at their top side. For example, the sensor or sensors may be overmolded on or in top side. For example, the sensors may include temperature sensors, humidity sensors, and also the pressure sensors noted above.
Furthermore, controller 70 is adapted to provide two-way communication between controller 70 and bed base control board 96 via a communication data bus 70a to transmit information or receive control signals or information relative to the surface. In addition, bed base main controller 96 may be configured to display information relative to mattress at a display 98, such as a display mounted at, in or to the footboard of the bed. Further, display 98 may be configured, such as by the processor or processors on the bed base main control board, to provide user interface devices to control the functions or therapies at mattress 10.
Referring to FIG. 11, controller 70 may also be in communication with a tilt sensor 95 mounted in, for example enclosure 54, which generates signals to controller 70 to indicate the angular position of the head section of mattress 10. Controller 70 may also control CPR reset valves 78C and 78D, which allows reinflation of the mattress 10 after a CPR has been initiated.
Further, to notify an attendant of an undesirable condition in mattress 10, for example when there is a loss of air or if there is an over pressurization condition, control system 82 includes an alarm such as a buzzer 70b, which the controller actuates when detecting an undesirable condition at mattress 10, such as a low pressure condition, as noted above. Additionally, control system 82 may include a speed control to limit the rate of inflation of the bladders and also a deflate assist valve 60e, which is in communication with controller 70 to provide a faster deflation of the bladders by making use of the fluid pumps 72a and 72b to suck the fluid from the bladders.
Referring again to FIG. 11, as noted control system 82 is in two way communication with bed based main control board 96 and display 96, which may comprise a touch screen display, such as described in U.S. applications entitled HOSPITAL BED, Ser. Nos. 11/612,428, filed Dec. 18, 2006; 11/612,405, filed Dec. 18, 2006; 11/642,047, filed Dec. 19, 2006; and 11/612,361, filed Dec. 18, 2006 (respectively) and U.S. application entitled PATIENT SUPPORT WITH IMPROVED CONTROL, Ser. No. 11/941,338, filed Nov. 16, 2007 , which are herein incorporated by reference in their entireties, and further may be configured to control the various function/therapies at mattress 10 and, as described in more detail below, display information relative to mattress 10 at display 98.
Referring to FIGS. 13A-13H, display 98 includes a display screen 100, which in the illustrated embodiment comprises a touch screen that is configured to display the different functions/therapies that can be administered at mattress and their various parameters associated with each function/therapy. Display screen 100 is configured by bed base main controller 96 to generate a plurality of touch screen areas 100a (with their respective icons, touch screen areas, and other images) that allow a user to select between various functions of the bed and at the bed, including the functions/therapies provided by mattress 10. For further details of the other bed base functions other than the mattress base functions, reference is made to the above referenced copending applications.
When a user selects a touch screen area associated with the mattress (which is labeled “support surfaces” in the illustrated embodiment), the bed base controller 96 will generate additional touch screen areas 100b, with each touch screen area forming a user actuatable device so that a user can select between the various functions/therapies provided at mattress 10. In addition, when selected, control board 96 generates two display areas or regions 102 and 104. Display area 102 includes an icon 102a representative of the mattress and, further, a second icon 102b, which illustrates the turning bladders and includes regions adjacent the icons that indicate the degree of inflation of the turning bladders. Display area 102 further includes two touch screen areas 102c that also form user actuatable devices that allow a user to initiate a maximum inflate condition and a stop function, for example, to stop all therapies. For a detailed description of the inputs and operational steps of the percussion therapy, reference is made to the flow chart in FIG. 12.
Display area 104 may include a window 106, which lists the activated therapies and touch screen areas 108, which allow a user to scroll between the activated therapies. An additional window 110 provides details relative to the selected activated treatment and, further, may include another touch screen area 112 to allow a user to go to a menu to select the specific parameters for display in window 110.
Referring to FIG. 13B, when a user selects the touch screen area 100b associated with the percussion treatment, main control board 96 generate displays 120 at screen 100 with a tabbed region 120a, which indicates the treatment selected. Display area 120 includes a pictorial display area 122 with a graphical representation of a patient's lungs and, further, with a plurality of touch screen areas 122a, which are visually linked to regions of the representative lungs via lines and allow a user to designate the region or regions of the patient's lung for treatment. Additionally, display area 120 includes a plurality of display windows 124a, 124b, and 124c, which each indicate a parameter relative to the selected treatment protocol. In addition, display area 120 further included a plurality of touch screen areas 126a associated with each of the windows to allow a user to increase or decrease the parameter, which is displayed in the window.
In addition, main control board 96 generates a third plurality of touch screen areas 100c, which appear with each of the treatment therapy windows described herein, and which allow a user to start, stop, or pause the treatment and, further, reset the treatment or return to the home screen or page for the mattress functions shown in FIG. 13A.
Referring to FIG. 13C, if a user actuates the touch screen area 100b associated with the vibration treatment, the main control board will generate a display area 130 at display screen 100, which similarly includes a tab portion 130a and, further, a display area 132 with a graphical representation of a patient's lung. In addition, display 130 includes a pair of touch screen areas 132a for a user to select where the treatment is to be applied, i.e. to the left or right lung. In addition, display area 130 includes two windows 134a and associated touch screen areas 136a which allow a user to increase or decrease the parameter associated with the windows, similar to the previous display area.
Referring to FIG. 13D, if a user selects the touch screen area associated with the rotation treatment, the main control board will generate a display 140 at display screen 100, which includes a tabbed portion 140, which similarly designates the selected treatment and a plurality of display areas 142a, 142b, 142c, and 142d. Further, display area 140 includes an icon 142, which is a graphical representation of the bed illustrating the turning bladders. The respective display areas 142a, 142b, 142c, and 142d are positioned around the icon 142 with the left most display area 142a including a graphical representation of the mattress illustrating the left turning bladder inflated and, further, a visual indicator 144b, which indicates the degree of inflation of the left turning bladder to provide a visual representation of the angle provided by the inflated bladder. Furthermore, display area 142a include a plurality of touch screen areas 144c that allow a user to increase or decrease the degree of inflation of the left bladder. In addition, display area 142a includes a window 146a and associated touch screen areas 146b, which display a parameter associated with the turning bladder, for example, the hold time, which can be adjusted by the touch screen areas 146b. Display area 142b is similar to touch screen area 142a but has an icon 144a illustrating the mattress with the right side turning bladder inflated and similarly includes touch screen areas 144c to allow a user to increase or decrease the inflation of the right side turning bladder.
Display area 142c includes a window 146a and touch screen areas 146b with window 146a also displaying a parameter relative to the rotational treatment, for example the hold time for the overall treatment, which can be adjusted using touch screen areas 146b. Display area 142d also includes a window 146a, which displays a parameter relative to the treatment, namely the duration of the treatment, which again can be increased or decreased using touch screen areas 146b. 
As best seen in FIG. 13E, when a touch screen area 100b associated with the turning function of mattress 10 is selected, the main control board will generate a display 150 at display screen 100, which also includes a tabbed portion 150a that identifies the selected treatment or function and a plurality of touch screen areas 150b and a display area 150c. Touch screen areas 150b allow a user to select between the right or left turning bladder. Once selected, the user can control the flow of air to and from the bladders 18d via control board 96 and controller 70 to thereby control the degree of inflation and the time of the inflation for the selected bladder using display area 150c. Display area 150c similarly includes a graphical representation of the mattress illustrating both turning bladders and touch screen areas 154a to control the inflation of the selected turning bladder. In addition, display area 150c includes indicators 152b to indicate the level of inflation and, therefore, provide a visual indication of the angle of the inflated turning bladders. Display area 150c also includes a window 156a, which displays a parameter relative to the turning function, for example the hold time, which can be similarly adjusted by the touch screen areas 154a. 
Referring to FIG. 13F, when a user selects the touch screen area associated with the immersion control function of mattress 10, the main control board 96 will generate display area 160 at display screen 100, which similarly includes a tabbed portion 160a and, further, an icon 160b, which is graphic representative of the immersion control function. Display area 160 additionally includes icons 160c, which indicate a no immersion condition and a full immersion condition, with a touch screen area in between icons 160c, which allow a user to increase or decrease the pressure in the bladders 18b via control board 96 and controller 70 to change level of immersion of the patient into mattress 10 between the no immersion condition and full immersion condition and anywhere in between. With immersion as the selected function, the main control board need not display the start, stop, and pause or reset touch screen areas associated with the treatment protocols.
Referring to FIG. 13G, if a user selects the touch screen area 100b associated with the low air loss system of mattress 10, the main control board generates a display area 170 at display screen 100. Display area 170 similarly includes a tabbed portion 170a, which indicates that the low air loss system function has been selected and, further, includes an icon 170b, which is a graphical representation of the mattress and the low air loss system. In addition, display area 170 includes touch screen portions 170d, which allow a user to increase or decrease the flow of air in the low air loss system, which increase or decrease is illustrated in the window 170c positioned between touch screen areas 170d and further, which include indicia to indicate whether the low air loss system is operating at a high level, low level, or whether it is off.
Referring to FIG. 13H, when a user selects the touch screen area 100b associated with the settings for the mattress, the main control board generates a display area 180 similarly with a tabbed portion 180a indicating that the setting selection has been made and, further, a plurality of overlapping tabbed windows 180b, which provide the user a menu of parameters associated with the selected treatment functions. Further, each window includes touch screen areas 180c associated with each parameter, which allow a user to adjust (e.g. increase or decrease) the parameter via control board 96 and controller 70, are positioned on either side of a window 180d that displays the status (e.g. the value) of the parameter selected. As will be understood from FIG. 13H, when a user selects one of the tabs 180e, the menu will change accordingly and list in a similar fashion as shown the various parameters associated with the selected treatment that can be adjusted along with the touch screen areas and windows to allow a user to change the various parameters and display the changed parameters.
Referring to FIGS. 14-18, various configurations of the surface or bladder layers are illustrated. Referring to FIG. 14, the numeral 16′ designates another embodiment of the bladder layer of the present invention. Bladder layer 16′ similar to layer 16 and includes a plurality of bladders 18′ that are arranged in a plurality of groups. A first group 20′ extends along the two sides, the head end and foot end of the layer and consist of generally box-shaped bladders, some with varying lengths or widths to accommodate the second or central group 28′ of bladders 18b′, 18c′ and 18d′, which each have a hexagon-shape. Some of the central bladders 18b′′ may have the fabric top sides described above, which assist in the moisture management of the surface. Further, like bladders 18c, bladders 18c′ may be configured to apply percussion or vibration therapy, while bladders 18d′ incorporate the immersion sensors described above.
Referring to FIG. 15, the numeral 210 designates another embodiment of the support surface of the present invention. Support surface 210 includes a base (not shown), a foam cradle 214, and a layer 216 of bladders 218, all optionally enclosed in a cover (not shown, see the previous description for suitable covers). In a similar manner to the surfaces described above, bladders may provide support to a patient's body and also provide one or more therapies. For example, one or more of the bladders may be adapted to provide vibration or percussion treatment to a patient and, further, to apply the treatment just below the patient's tissue with the therapy force is effectively only separated from the patient's skin by the cover and any possible sheet positioned between the patient and the surface. In the illustrated embodiment, layer 216 includes a plurality of bladders 218 that are arranged in several groups and several zones similar to bladders 18. For details of the bladders and how the can be made reference is made to the descriptions provided above in reference to bladders 18.
In the illustrated embodiment, the head end of the surface is formed by the foam crib 214, which includes a transfer section of foam 214a that extends across the width of the surface at the head end and may provide support to the head end of a patient. Similar to layer 16, layer 216 includes a first group 220 of bladders 218a that are arranged to extend along the sides 222 and 224. In the illustrated embodiment, first group 220 of bladders consist of a single row of bladders at the back seat and leg section of the surface 210 but may include a second row of bladders at the sides of the foot end of the surface.
Also similar to the previous embodiment, bladders 218 include a second group 228 of bladders 218b, which extend between the first group of bladders from the foot end of the surface to adjacent the foam head section 214a of foam crib 214. In this manner, the number of zones may be reduced and as shown in FIG. 15A may be arranged into three zones, a back section, seat section, and leg section (with the foot and leg sections combined). In the illustrated embodiment, the top surface of foam head section 214a is flush with the top surface of bladders 218b before they support a patient.
Bladders 218b of the second group of bladders are similarly configured so that their edges do not form a continuous linear edge across the surface to reduce the creation of continuous edges that span the width or length of the layer. In the illustrated embodiment, bladders 218b are multi-sided, such as hexagonal box-shaped bladders, but may comprise rounded bladders, including circular bladders, in other word can-shaped bladders, or double rounded such as a peanut-shaped bladder.
In addition, a third group 232 of bladders 218c may be arranged in a central portion of the chest area of a patient, which may be used to apply one or more therapies to the patient and, further, arranged in two groups of three zones (top, middle, bottom of each lung) similar to the previous embodiment, with one group for applying treatment to the patient's left lung with the other group applying treatment to the patient's right lung. Each bladder in the third group of bladders may be individually actuated, further may be actuated in a manner to create a rolling effect of the percussion or vibration treatment.
A fourth group 234 of bladders 218b may incorporate sensors, such as the immersion sensors described above, which are located for example in the seat section of the surface where the greatest immersion typically can occur. For further details of the immersion sensors, reference is made to FIGS. 10A and 10B.
In FIG. 16, surface 310 includes a foam crib 314 with both head end sections 314a and foot end side sections 314b and 314c and with side sections 314d, which may generally replace the first group of bladders 220 described in reference to the previous embodiment. For additional details of the bladders of bladder layer 316 and the various groups of bladders that may be provided in central portion of the surface, reference is made to the previous embodiment. For details of the bladders and how the can be made reference is made to the descriptions provided above in reference to bladders 18.
Referring to FIG. 17, surface 410 also includes a foam crib 414, similar to foam crib 214, and a bladder layer 416. Bladder layer 416 includes a first group 420 of bladders 418a, which extend along opposed sides of the surface and which each have a smaller lateral extent than the bladders 218a of group 220 of surface 210 but retain the wider set of bladders at the sides of the foot end of the surface. The central bladders of layer 416 are similar to the bladders in surface 310 and have two additional columns of bladders than bladders 218b at the central cross-section to extend further across the surface.
Referring to FIG. 18, surface 510 includes a foam crib 514 and bladder layer 416. Foam crib 514 includes a head foam section 514a and foot sections 514b and 514c. Bladder layer 516 is similar to the bladder layers previously described in reference to FIG. 15 but instead extend across the full width of the surface.
Referring to FIG. 19, the numeral 610 designates yet another embodiment of the surface of the present invention, which incorporates a foam crib 614 and a bladder layer 616, which is similar to bladder layer 316. In the illustrated embodiment, foam crib 614 also includes a head section 614a and foot sections 614b and 614c and, further, forms side bolsters 614d and 614e, which extend along the opposed sides of bladder layer 616.
It should be understood that various combinations of the bladders and foam crib sections may be used to accommodate the specific needs of patients. While several variations have been shown and described it should be understood that features from one surface can be combined the features of another surface described here.
Referring to FIG. 20, the numeral 248 designates another embodiment of the frame of the patient support of the present invention. Similar to frame 48, frame 248 has incorporated therein conduits for directing the flow of air through mattress from various valve assemblies and pumps, described more fully below. Frame 248 is formed from a pair of side frame members 250 and two transverse members in the form of a head end enclosure 256 and a foot end enclosure assembly 258, which forms a housing for the control system for the surface. For details of enclosure assembly reference is made to the enclosure assembly 58.
Enclosure 256, side frame members 250, and enclosure assembly 258 are connected so they form frame 248, with side frame members 250 having at least a flexible portion so that frame 248 can be articulated about one or more axes. Referring again to FIG. 20, side frame members 250 mount on one end to enclosure 256 and on their opposed ends to enclosure 258.
To allow frame 248 to flex and accommodate the surface movement (e.g. folding), side frame members 250 incorporate flexible portions 250a, which are formed by interconnected linkages 250b, with each linkage being pivotally mounted to the adjacent linkage to form flexible sections that can pivot about horizontal axes along at least a portion of the length of the surface. Flexible portions 250a optionally couple to rigid channel-shaped member 250c on one end and to rigid channel-shaped members 250d at their opposed ends, which respectively mount the side frame members 250 to the respective enclosures. The channel-shaped members 250c and 250d are mounted to their respective enclosures by brackets 250e and 250f (see FIG. 26 for brackets 250f).
In the illustrated embodiment, each linkage member 250b includes a transverse passage, which when joined with their adjacent linkages form a passageway through the flexible portions 250a of side frame members 250 to allow conduits, such as tubes/tubing, to extend through the side frame members. When the tubes or tubing exits the linkages they are then supported by the lower webs of the respective inverted channel-shaped members 250e and 250d. Flexible portions 250a of members 250 are formed from a rigid material, such as plastic or a metal, including aluminum. Similarly, channel-shaped members 250b and 250c may also be formed from a rigid material, such as plastic or a metal, including aluminum.
Similar to the previous embodiment, the conduits are provided that extend through side frame members 250 to deliver air to the bladders and for exhausting air from the bladders, for example, to administer CPR. As best understood from FIGS. 20 and 21, the respective conduits are in fluid communication with the various valves 260 provided at the head end enclosure. Referring to FIGS. 21 and 22, enclosure 256, which is formed from an extrusion 256a and cover 256b, houses a plurality of inflation valves 260a and, further, turn valves 260b, which are controlled by PC boards 265a and 265b also housed in enclosure 256, which are in communication with controller 70. In the illustrated embodiment, bladder layer 216 may include four zones, with each zone being controlled by a respective valve 260a. Further, each side of the surface may incorporate a turning bladder (218d, see FIG. 25A) as noted, with each turning bladder being inflated by its respective valve 260b. 
Enclosure 256a also supports a plurality of percussion and vibration valves 260c, which deliver the pressurized air to the respective percussion/vibration bladders with sufficient pressure to generate the forces needed to provide the percussion and vibration therapy. The percussion/vibration valves 260c are powered by a printed circuit board 265c, also mounted in enclosure 256 and in communication with controller 70, which are best seen in FIGS. 21-23. In addition, the control system may include a diverter valve 260d, which it can use to divert exhaust air from the bladders 218c to bladders 218b and 218a (FIG. 15A) to avoid over-pressurization of bladders 218c. 
As noted in reference to the previous embodiment, any one of the surfaces 210, 310, 410, 510, or 610 may incorporate a low air loss system similar to that described above. The low air loss system is supplied air via a low air loss valve 274a (see FIGS. 21-23). As noted above, the bladders may also be evacuated of air through the tubing or tubes that run through side frame members 250, which are in fluid communication with deflate valve 260e (see FIGS. 21 and 23), for a CPR event and also to control inflation of the bladders. In this manner, deflation of the respective bladders may be achieved by way of valve 260e, in addition to the CPR valve 278 described more fully below.
Referring to FIG. 25, any of the surfaces (10, 110, 210, 310, 410, or 510) may incorporate a single CPR valve 278, which is manually actuatable between a closed configuration where the flow of air from the mattress is blocked at the CPR valve, and an open position where the air can flow from the mattress through the CPR valve, and further configured to auto reset to its closed position after a CPR event. In one embodiment, the control system is in communication with the CPR valve and is configured to trigger the CPR valve to auto reset to its closed position after a CPR event. For example, the control system niay includes a user input device, such as a touch actuatable device, such as a button, including a touch screen button, which is configured to trigger the CPR valve to auto reset to its closed position upon an input at said user input device.
For example as shown in FIG. 25A, CPR valve 278 may include a housing with two chambers, one in fluid communication with the mattress and the other in selective fluid communication with the atmosphere. The housing includes an outlet, and a check valve and an electrically controlled valve both in fluid communication with the second chamber. Positioned in the housing are a piston and a spring, which biases the piston to a closed position wherein the outlet is isolated from the first chamber. The piston is coupled to an actuator, which when actuated moves the piston against the force of the spring and past the outlet so that the first chamber is in communication with the atmosphere and the air from the mattress can discharge through the outlet. When the piston is moved to its open position, air from the second chamber is discharged though the check valve, which generates a vacuum in the second chamber, which holds the piston its open position. The vacuum is then released by an electrically operated valve, such as a solenoid valve 278a, which is in communication with the control system to provide an automatic reset for the CPR valve. Once the valve 278a is opened, the pressure in the spring chamber is allowed to increase and the vacuum is released allowing the spring to return the piston to its closed position until the CPR tether is once again pulled. Once the CPR event is over, the user input device may be actuated to trigger the electrically operated valve to release the vacuum pressure.
To actuate the CPR valve, the surface may include a cable system 279. Referring to FIGS. 23, 24A, and 25, cable system 279 includes a first cable section 279a that extends from the CPR valve to the right side of the surface (as viewed in FIG. 25), with its sheath anchored to bracket 279c, to couple to a spring biased pin or plunger 279b on its other end, which is supported in a bracket 279d. (see e.g. FIG. 24). A tether, such as a strap 280, is coupled to the plunger, which is accessible exteriorly of the surface so that an attendant can simply pull on the strap to open the CPR valve. Cable system 279 includes a second cable portion 279e, which extends from the CPR valve to the left side of the surface, with its sheath anchored on bracket 279c, and similarly couples to a plunger 279f (see FIG. 23) for coupling to a second tether (not shown), which is accessible exteriorly of the surface on the other side of the surface for actuation by a caregiver. When one of the tethers is actuated, the cable system opens the CPR valve (278), which moves the CPR valve's piston between a closed position and an open position in which the air in the bladders is allowed to dump through the CPR valve to the atmosphere.
Accordingly, the present invention provides a patient support that provides a support that can apply treatment protocols to the patient using a single layer of the surface so that treatment can be applied without deflating any support bladders. Instead, some of the support bladders are also the treatment bladders. In this manner, the treatment bladders can be just below the surface of patient's tissue—and only separated by a cover. Further, because the percussion/vibration bladders are individually controlled, the treatment can be customized both as to timing and intensity of impact. The arrangement of the percussion/vibration bladders in the general shape of lungs, with indicia on the cover to allow caregiver to align patient's body properly on surface with percussion/vibration bladders, assures more precise treatment. Additionally, with this construction, the patient treatment protocols may be applied while the patient is being turned. Furthermore, the mattress of the present invention provides greater control over the immersion of the patient into the surface and, further, in a manner to reduce high pressure points at the support surface.
The modular nature of the mattress with a plurality of enclosures or housings at a plurality of positions around perimeter of mattress allow for multiple possible locations of the controls, which provides for local control and optionally direct or near direct coupling of control valve to bladders. Tubing can be eliminated to some degree. This also achieved in part by the formation of the mattress frame from members that form conduits for directing air to the various bladders.
While several forms of the invention have been shown and described, other changes and modifications will be appreciated by those skilled in the relevant art. Therefore, it will be understood that the embodiments shown in the drawings and described above are merely for illustrative purposes, and are not intended to limit the scope of the invention which is defined by the claims which follow as interpreted under the principles of patent law including the doctrine of equivalents.

## Claims

1. A patient support for supporting a patient, said patient support comprising:
an inflatable mattress having a plurality of rows of bladders forming at least part of a patient support surface and extending laterally across the mattress, each row having a plurality of bladders wherein each row is formed by a plurality of adjacent bladders, said bladders forming at least two zones, and each bladder in each respective zone being in fluid communication with each other bladder in said respective zone;
a pneumatic system for inflating said bladders; and
a control system, said control system including a first sensor associated with a first respective bladder of a first respective zone and a second sensor associated with a second respective bladder of a second respective zone, each of said first and second sensors including an emitter and a receiver, each emitter directing light into its respective bladder, and each receiver being adjacent its associated emitter and receiving a reflection from the light of its associated emitter directed into its respective bladder, said control system further including a reference receiver associated with one of said first and second sensors to account for decay in said emitter of said one of said first and second sensors, and said control system determining the immersion of a patient into said mattress in each of said zones based on the reflections received by said receivers, and said control system comparing the immersions at each respective zone with a defined minimum immersion for each respective zone, and when said control system determines that the immersion of one of said respective bladders deviates from its defined minimum immersion said control system adjusts the pressure in the one of said respective bladders.

2. The patient support according to claim 1, wherein at least one of said emitters and said receivers is located outside said respective bladders.

3. The patient support according to claim 2, wherein said emitters are located outside said respective bladders, and each of said respective bladders includes a transparent region to allow light to pass from said emitters into said respective bladders.

4. The patient support according to claim 2, wherein both said emitters and said receivers are located outside said bladders.

5. The patient support according to claim 4, wherein each of said first and second sensors is supported on a printed circuit board, said circuit boards being mounted at the undersides of said bladders.

6. The patient support according to claim 1, wherein the reflections received by said receivers are used by said control system to determine the change in the volumes of the respective bladders.

7. The patient support according to claim 1, wherein the insides of said respective bladders are each formed from a light material to minimize absorption of the light into the bladder.

8. The patient support according to claim 7, wherein the insides of said respective bladders are white.

9. The patient support according to claim 7, wherein the outsides of said respective bladders are opaque to filter outside ambient light.

10. The patient support according to claim 7, wherein each of said respective bladders has an outer layer that blocks light transmission into said respective bladders from the outside ambient light.

11. The patient support according to claim 7, wherein said bladders are adapted to block at least some of the outside ambient light.

12. The patient support according to claim 1, wherein each of said bladders has a height (H) and a width (W) wherein H>2W.

13. The patient support according to claim 1, wherein said top sides comprise fabric.

14. The patient support according to claim 13, wherein said fabric is moisture permeable.

15. The patient support according to claim 1, wherein said emitters comprises infrared emitters or optical cables emitting light.

16. The patient support according to claim 1, wherein said control system is operable to display an immersion map of said mattress based on the detected immersions.

17. A patient support for supporting a patient, said patient support comprising:
an inflatable mattress having a plurality of rows of bladders forming at least part of a patient support surface and forming at least two zones, each row extending laterally across the mattress and having a plurality of adjacent bladders;
a pneumatic system for inflating said bladders; and
a control system, said control system including a first height sensor associated with a first respective bladder of a first respective zone, a second height sensor associated with a second respective bladder of a second respective zone, each height sensor generating a signal based on the height of its respective bladder, said control system further including a reference sensor for at least one of said height sensors to account for decay in said at least one of said height sensors, and said control system determining the immersion of a patient into said mattress in each of said zones based on the signals from said sensors, and said control system comparing the immersions at each respective zone with a defined minimum immersion for each respective zone, and when said control system determines that the immersion of one of said respective bladders deviates from its defined minimum immersion said control system adjusts the pressure in the one of said respective bladders.

18. The patient support according to claim 17, wherein said height sensors measure reflected light or inductance.

19. The patient support according to claim 17, wherein said control system compares the immersions to a defined maximum immersion, and said control system configured to adjust the pressure in said bladders to maintain the immersion of the patient between said predefined minimum immersion and said predefined maximum immersion.