GB2484885A

GB2484885A - Multi layered, absorbent, disposable patient transfer assembly

Info

Publication number: GB2484885A
Application number: GB0914586A
Authority: GB
Inventors: Muhammed Aslam Nasir
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-08-20
Filing date: 2009-08-20
Publication date: 2012-05-02
Also published as: GB0815154D0; WO2010020818A2; GB0914586D0; WO2010020818A3

Abstract

A disposable patient transfer sheet comprising an upper layer 10 adapted to minimise the damage to a patient's skin, a second liquid absorbent layer 11 and a lower layer 12 adapted to be substantially impermeable to the passage of fluids. The assembly includes arm restraint means which may restrain the elbow and be formed by straps with a ring or loop and fastening means. Also disclosed are flexible handles with means to secure them when not in use and a pressure relieving means which may be a foam, gel, water or air cushion. There may also be a passageway 16 in the assembly adapted to circulate temperature conditioned fluid and an air blower and vent means are also disclosed. The layers may be bonded using ultrasonic welding and there may be an insulating hood. Also disclosed is a disposable mat assembly with a tear resistant upper layer.

Description

DISPOSABLE PATIENT TRANSFER ASSEMBLY

Field of the Invention

The present invention relates to devices for use during medico-surgical treatments. It is particularly applicable, but in no way limited, to patient transfer sheets and to absorbent mats, as would be used in a hospital operating theatre, ambulances, wards and nursing care homes.

Background of the Invention

In a hospital, nursing care home or by ambulance crew it is often necessary to transfer a patient or an incapacitated person between different horizontal supporting surfaces such as a hospital bed, a patient trolley and/or an operating table. Patient transfer boards in conjunction with draw sheets and/or a canvas are commonly used for this purpose. A draw sheet and/or canvas is placed under the patient and then the board e.g. Patslide (RTM) is placed partially beneath the patient lying on, say, a bed so that it provides a bridge to another surface, say a trolley. Once the board has been so positioned nursing staff or other hospital personnel can slide the patient across the board from the bed to the trolley using the draw sheet and/or canvas. In use, once the board has been properly positioned, the nurse or nurses leans over the trolley, grabs hold of the side of the draw sheet and pulls the draw sheet and thus the patient towards her thus transferring the patient from one surface onto the other. The draw sheet and/or canvas thus facilitate sliding of the patient across the transfer board.

Nevertheless, injuries to personnel can still occur when a draw sheet is used as the personnel reach across the bed or trolley during the transfer. Furthermore, the present use of draw sheets does not meet the European Community regulation that personnel lean no more than 10° from the vertical during a patient transfer.

Reusable flexible patient transfer sheets have been developed such as those described in GB 2294883 (A C Daniels & Co Ltd) wherein the patient transfer sheet is placed beneath the patient and the operator slides the patient from a first surface to a second surface by pulling on handles provided on the patient transfer sheet.

However, most such reusable patient transfer sheets are generally formed from woven, synthetic textile material and are relatively expensive to make. The patient transfer sheets and/or canvas are used, inter alia, to transfer patients from hospital beds to gurneys and from gurneys to operating tables. During an operation the patient transfer sheet remains under the patient, to enable the patient to be transferred back to a gurney after the operation has been completed. Such operations can last for many hours during which time bodily fluids including blood, mucus, pus, urine and faeces etc come into contact with the patient transfer sheet and/or canvas. Laundering does not always remove the stains caused by body fluids and does not always kill off the organisms which cause infections from the bodily fluids, particularly when laundering at temperatures which the patient transfer sheets will withstand. As a result, patient transfer sheets have been laundered and dried at temperatures greater than they will actually withstand in an attempt to kill off all infectious organisms and this has resulted in the destruction of the patient transfer sheets. If the draw sheet and/or canvas are too badly soiled with the bodily fluids then it/they will often be sent for disposal rather than for laundry. The use of reusable patient transfer sheets can thus increase the chance of patient-to-patient or patient-to-personnel contamination due to the harbouring of infectious organisms.

In addition, during an operation, which can last for many hours, the patient is generally given an anaesthetic, which frequently includes a muscle relaxant, and which results in a lowering of the patient's blood pressure, particularly in patients with fractured pelvis, lower limb bones fractures, paraplegic or quadriplegic patients and elderly patients.

The combination of this and a protracted period of contact with a sling and hard surfaces of a canvas can cause substantial problems with respect to reduced or impaired blood supply and bedsores causing ischaemia of the patient's skin.

Such bedsores or damage to the patient's skin can also lead to hospital acquired infections of a serious nature. Such bedsores or pressure sores also tend to occur more frequently in the elderly, as can be seen, for example, by the article of M. Versluysen, How Elderly Patients with Femoral Fractures Develop Pressure Sores, British Medical Journal, 1986, 292, 1311-13.

A further type of reusable patient transfer sheet is manufactured by Arjo Ltd of Gloucester, United Kingdom and sold under the trademark MAXISLIDE (RTM). This device, whilst having the advantage of low friction to facilitate transfers, has none of the absorbent properties of a canvas device.

A further problem with known patient transfer sheets is that they do not provide any reliable method for securing the patient in position once on the operating table. In particular, there is no assembly for securing the patient's arms and/or legs. If a patient's arm or leg were to accidentally fall off the trolley or operating table, this can lead to fracture, dislocation or neuronal damage.

A further problem faced by operating staff is that during certain operations body fluids from the patient may fall onto the floor around the operating table. These present a safety hazard in a number of ways. They may cause the operating staff to slip, and have to be thoroughly cleaned off between operations to avoid cross-contamination with the next patient. This cleaning regime takes a considerable time which could otherwise be used for operating. A mat in a similar absorbent material is also described which weakly sticks to the floor during an operation in the immediate vicinity of the operating table where blood and body fluids are likely to fall during a particular operative procedure e.g. neurosurgical, cardio-thoracic, abdomino-perineal, urological, obstetric and gynaecological proced ures.

It is an object of the present invention to overcome or at least mitigate some or all of these problems.

Summary of the Invention

According to a first aspect of the present invention there is provided a disposable patient transfer assembly according to claim 1. Such a patient transfer assembly comprising a first or uppermost-in-use layer, a second or intermediate layer and a third or lowermost-in-use layer, wherein said first layer is adapted to minimise the damage to a patient's skin when disposed against the skin of a patient, said second layer is liquid absorbent and said third layer is adapted to be substantially impermeable to the passage of fluids. This disposable combination is particularly advantageous and means that the patient can be left on the patient transfer assembly during operations and the like and the assembly will absorb any bodily fluids from the operation and can be disposed off afterwards with minimal expense.

In one embodiment the upper surface of the intermediate absorbent layer will incorporate anti-siphon valve properties which lets the body fluids in but does not let fluids leak back thus keeping the skin surface of the patient dry.

In a preferred embodiment the patient transfer assembly further comprises a plurality of passageways adapted to circulate temperature-conditioned fluid within the patient transfer assembly. Preferably the fluid is air that enables the patient lying on the patient transfer sheet to be warmed or cooled as necessary. During an operation, the patient is covered by multiple layers of sterile sheets so when the warm or cold air escapes from a porous arrangement in the upper surface of the third layer or from the sides parallel to the patient of the sheet and/or canvas, air thus escaping gets somewhat trapped underneath these sterile sheets for a longer periods of times to provide a maintained manner of warmth or cool to the patient. This is particularly advantageous and means that a single transfer sheet can be used for not only transferring the patient and absorbing fluids but also warming or cooling the patient during operations as necessary.

In another preferred embodiment the patient transfer assembly further comprises a plurality of pads or insulated electric coils adapted to temperature-condition the patient transfer assembly to keep the assembly to acceptable temperatures for keeping patient's temperature within normal limits.

Preferably the third layer is formed from a laminate comprising at least two sheets of material wherein two of the sheets are bonded together so as to form a plurality of passageways adapted to circulate temperature conditioned fluid within and out of the patient transfer assembly. The uppermost of these two sheets may contain perforations or micro-perforations to allow the conditioned air to escape into the vicinity of the patient. Such a construction has the advantage that the patient transfer assembly can be easily and cost effectively produced in a disposable format.

In an alternative arrangement the passageways are provided by pre-formed tubing.

The tubing can be disposed between any of the layers of the patient transfer assembly and may even be disposed within the second layer such that the tubing is close to the patient to warm or cool the patient effectively, preferably the tubing is disposed within the third layer or between the second and third layers.

In a particularly preferred arrangement the passageways are provided with a mechanism to prevent total collapse of the passageways in use, under the body weight of a patient. This is advantageous because the passageways will always be available, and will not entail disturbing the patient or interrupting an operation to pass conditioned fluid through the passageways. The mechanism may comprise a plurality of internal splines extending along the longitudinal axis of the tubing and preferably are located on the internal walls of the tubing. The splines interact with each other when pressure is applied to the external wall of the tubing such that the tube does not completely collapse on itself. Such tubing is well known for use in oxygen supply tubes. In order to enable conditioned fluids such as air to flow through the passageways the passageways are adapted to be connected in use to an air blower. Such air blowers are commonly available in operating theatres and in ambulances, the patient can be placed on the patient transfer assembly when collected in an ambulance and warmed or cooled as needed and transferred as necessary using the patient transfer assembly.

In a preferred arrangement the patient transfer assembly has arm restraint means.

Preferably the arm restraint means are adapted to restrain the arms of a patient leaving the arms exposed for insertion of medical equipment. This again is particularly applicable for the continued use of the patient transfer assembly in operating theatres where it is difficult to locate patient's arms in a manner wherein the hands and forearms are accessible for the insertion of intravenous drips or an arterial line by anaesthetist or anaesthetic nurse and the like whilst not getting in the way of surgeons, whilst in a comfortable manner for the patient. Preferably the arm restraint means comprises elbow restraints and even more preferably the arm restraint means comprises a first strap with a ring adapted to fit around the elbow of a patient, most preferably the arm restraint means comprises a second strap with a ring adapted to fit around the elbow of a patient, wherein the ring is formed of a material adapted to minimise damage to the patient. Such an arrangement maximises the amount of arm available for medical insertions whilst retaining the arm in a comfortable position with minimal stress to the patient's arm out of the way of the surgeons during an operation for example. It is particularly preferred when the first and second straps are provided with a fastening means for holding the arm in the desired position such as a hook and loop fastener. In such an example a hook fastener is provided on a first strap and a loop fastener is provided on the second strap. In addition a hook/loop fastener is provided on the underside of the lower layer, or at some other convenient location, to fasten the first and/or second straps away when not in use. This is particularly advantageous as it means that nurses can put the arm restraint means away when not in use such that it/they does/do not interfere when transferring the patient for example.

The patient transfer assembly may in addition or in the alternative be provided with leg straps. A hook and loop fastener arrangement of a single but wider strap to contain and retain the legs of a patient, either together or individually, can be provided, thus avoiding the legs falling off an ambulance trolley or an operating table.

In a preferred arrangement the patient transfer assembly has handle means preferably disposed along the longest edges of the patient transfer assembly. This enables the nurses to hold onto the handle means when moving the patient using the patient transfer assembly. In one arrangement the handle means comprise a plurality of openings provided along at least one edge of the patient transfer assembly and preferably the handle means are provided in the third layer. In an alternative the handle means comprise a plurality of straps provided along at least one edge of the patient transfer assembly, preferably the straps are formed of a flexible material. The straps are preferably provided with a fastening means for securing the straps out of the way when not in use, and preferably the fastening means is a hook and loop fastener arrangement. In this way the handle means do not cause obstruction when the patient is being operated on for example.

Alternatively the handle means comprises substantially rigid handles provided along at least one edge of the patient transfer assembly preferably the handles are provided with a cushioning means to placate damage to the patient.

The patient transfer sheet is designed and adapted to bear up to 300kgs of patient body weight.

In an alternative arrangement especially suitable for a paediatric patient, the patient transfer sheet and/or canvas for transfers is provided with an insulating hood. This is particularly advantageous because it enables the patient's head to be insulated during an operation, as most of the heat escapes through the head in children.

The patient transfer assembly may also include a head support, preferably in the form of an inflatable/deflatable or a preformed pillow. This may be inflated with the temperature-conditioned air used to heat or cool the patient as described above.

In the context of the present invention the term plurality is defined as one or more and a fluid may comprise a gas which specifically includes but is not limited to air, or a liquid which specifically includes but is not limited to water and bodily fluids such as blood and urine.

A skin temperature sensor may be incorporated into the assembly in the upper layer, being in contact with the skin of the patient, to monitor the patient's body/skin temperature signifying the skin perfusion of the patient.

Blood flow impedance sensors may also be incorporated to monitor the adequacy of the skin perfusion pressures.

In a further embodiment, intermittent calf compression cuffs are built into the assembly in order to avoid or minimize DVT (Deep Vein Thrombosis) and designed for use with a machine such as a FLOWTRON (RTM) device manufactured by Huntleigh Technology plc of Luton, Bedfordsh ire, UK.

There may also be provided a cautery plate built into the transfer assembly ready to be attached to a cautery machine used during surgical procedures.

An important feature is that disposable patient transfer assemblies according to the present invention are radio-translucent (X-Ray, MRI and CT translucent) and are therefore compatible with such investigative procedures.

In summary, the present invention provides for a disposable patient transfer assembly comprising a first or uppermost-in-use layer, a second or intermediate layer and a third or lowermost-in-use layer, wherein said first layer is adapted to minimise the damage to a patient's skin when disposed against the skin of a patient, said second layer is liquid absorbent and said third layer is adapted to be substantially impermeable to the passage of fluids, further comprising an arm restraint means.

Preferably the arm restraint means comprises elbow restraints.

Preferably the arm restraint means comprises a first strap incorporating a ring or loop adapted to fit around the elbow of a patient.

Preferably the arm restraint means further comprises a second strap incorporating a ring or loop adapted to fit around the elbow of a patient.

Preferably the first and second straps are provided with a fastening means for holding the arm in the desired position.

Preferably the ring or loop is formed of a material adapted to minimise damage to the patient.

Preferably the first strap is integral with the second strap Preferably the assembly further comprises handle means.

Preferably the handle means comprise a plurality of straps provided along at least one edge of the patient transfer assembly.

Preferably the straps are formed of a flexible material.

Preferably the straps are provided with a fastening means for securing the straps away when not in use.

Preferably the assembly further comprises at least one area of pressure relieving material The present invention also provides for a disposable patient transfer assembly comprising a first or uppermost-in-use layer, a second or intermediate layer and a third or lowermost-in-use layer, wherein said first layer is adapted to minimise the damage to a patient's skin when disposed against the skin of a patient, said second layer is liquid absorbent and said third layer is adapted to be substantially impermeable to the passage of fluids, further comprising at least one area of pressure relieving material.

Preferably the pressure relieving material is formed from an air alternating cushion.

Preferably the pressure relieving material is formed from a static air cushion.

Preferably the pressure relieving material is formed from a foam.

Preferably the foam is a memory foam.

Preferably the pressure relieving material is formed from a gel cushion.

Preferably the pressure relieving material is formed from a water cushion.

Preferably the areas of pressure relieving material are located at the head area and/or shoulder areas and/or back area and/or foot area.

Preferably the pressure relieving material located at the head area has a neck recess and/or a head recess.

Preferably the assembly further comprises a passageway adapted to circulate temperature conditioned fluid within the patient transfer assembly.

The present invention also provides for a disposable patient transfer assembly comprising a first or uppermost-in-use layer, a second or intermediate layer and a third or lowermost-in-use layer, wherein said first layer is adapted to minimise the damage to a patient's skin when disposed against the skin of a patient, said second layer is liquid absorbent and said third layer is adapted to be substantially impermeable to the passage of fluids, further comprising areas of pressure relieving material, further comprising a passageway adapted to circulate temperature conditioned fluid within the patient transfer assembly Preferably the third layer is formed from a laminate comprising two sheets of material and wherein the two sheets of material are bonded together so as to form a passageway adapted to circulate temperature conditioned fluid within the patient transfer assembly.

Preferably the passageway is provided by a pre-formed tube.

Preferably the passageway is provided by a built-in tube.

Preferably the passageway is provided with a mechanism to prevent total collapse of the passageways in use, under the body weight of a patient.

Preferably the passageway is provided with an internal spline extending along the longitudinal axis of the passageway.

Preferably the passageway is adapted to be connected in use to an air blower.

Preferably the passageway incorporates a vent to allow air to exit the passageway in a controlled manner.

Preferably the assembly further comprises an insulating hood.

Preferably the assembly further comprises a fastening means for securing the legs of the patient.

Preferably the first, second and third layers are bonded together around the edges of the patient transfer assembly.

Preferably the layers are bonded together using ultrasonic welding.

Preferably the first layer is formed from a non-woven material The present invention also provides for method of manufacturing a disposable patient transfer assembly comprising the steps of: a) providing a layer of liquid impermeable material; b) providing a layer of liquid absorbent material; c) providing a layer of liquid permeable material; d) arranging the layer of liquid absorbent material onto the layer of liquid impermeable material; e) arranging the layer of permeable material onto the layer of liquid absorbent material; and f) bonding the layers together Preferably the method of bonding is ultrasonic welding.

Preferably the layer of liquid impermeable material is folded over at least one of the edges of the layer of liquid permeable material and bonding takes place in the overlapping region.

Preferably there is provided a layer of adhesive between each of the layers.

Preferably the method further comprises bonding handles to the layer of liquid impermeable material.

Preferably the bonding is ultrasonic welding.

The present invention also provides for a disposable mat assembly comprising a first or uppermost-in-use layer, a second or intermediate layer and a third or lowermost-in-use layer, wherein said first layer is adapted to be resistant to tearing when walked on and is substantially fluid permeable, said second layer is liquid absorbent and said third layer is adapted to be substantially impermeable to the passage of fluids. wherein said assembly comprises a fourth layer comprising an adhesive layer, preferably a low-tack adhesive layer.

Brief Descriition of the Drawings The invention will now be described by way of example only with reference to the accompanying drawings, wherein: Figure 1 illustrates the layered construction of a patient transfer sheet according to the present invention; Figures 2 to 5 inclusive illustrate different handle types for a patient transfer sheet according to the present invention; Figures 6, 7 and 8 illustrate different arm support means to support the patient's arms suitable for incorporation into a patient transfer sheet according to the present invention; Figures 9 and 10 show various arrangements of air channels incorporated into a patient transfer sheet according to the present invention, designed to circulate warm or cooled air under the patient; Figure II shows the cross-section of a proprietary make of crush-resistant tubing, suitable for incorporating into a patient transfer sheet according to the present invention and designed to circulate warm air under the patient; Figure 1 IA shows the cross-section of an alternative form of crush-resistant tubing; Figure 12 illustrates a patient transfer sheet according to the present invention incorporating a hood adapted to be pulled up around the patient's head leaving the face open; Figure 13 illustrates the layered construction of a patient transfer sheet according to a further embodiment with a single plastic bottom sheet; Figure 14 illustrates the layered construction of an absorbent mat incorporating an adhesive layer according to a further aspect of the present invention; Figure 15 illustrates an absorbent mat according to the present invention for use in pelvic, urological, lower limb, gynaecological and obstetric operations and procedures; Figure 16 illustrates an absorbent mat for use in thoraco-abdominal operations and procedures including cardiac surgery; Figure 17 illustrates a mat for head, neck, ophthalmic and neurological operations and procedures; Figures 18, 19 and 20 illustrate mat arrangements for use in multiple trauma operations and procedures; Figure 21 illustrates an absorbent mat according to a further embodiment of the present invention incorporating areas of pressure relieving material; Figures 22 to 25 illustrate a patient transfer sheet according to a further embodiment of the present invention comprising pressure relieving material, alternative "lower arm" arm restraints, foot restraints and handles; Figures 26 and 27 illustrate a patient in position on a patient transfer sheet of Figures 22 to 25; Figures 28 to 32 illustrate a patient transfer sheet according to a further embodiment of the present invention comprising pressure relieving material, alternative "elbow" arm restraints, foot restraints and handles; Figure 33 illustrates an "elbow" arm restraint of Figures 28 to 32; Figures 34 to 38 illustrate views of a back area pressure relieving material; Figures 39 to 41 illustrate views of a shoulder area pressure relieving material; Figures 42 to 46 illustrate views of a foot area pressure relieving material; Figures 47 to 51 illustrate views of a head and neck area pressure relieving material; Figures 52 to 54 illustrate an example of a procedure for manufacturing a patient transfer sheet according to a further embodiment of the present invention

Detailed Description of the Preferred Embodiments

Referring now to the drawings, Figure 1 shows a cross-section of a patient transfer assembly comprising a first or uppermost-in-use layer 10 of substantially fluid permeable material being adapted to minimise the damage to a patient's skin when disposed against the skin of a patient. There is then provided a second or intermediate layer 11 of a liquid absorbent material and finally a third or lowermost-in-use layer 12 of substantially fluid impermeable material being sufficiently strong to support the weight of a patient.

The terms "uppermost-in-use layer" and "lowermost-in-use layer" refer to the position of the layers when use to transport the patient or in use underneath the patient in an operating theatre.

Preferably the first 10 and second 11 layers form an absorbent pad and preferably the absorbent pad is of sufficient length and width to underlie the entire body of a patient placed on the patient transfer assembly. The size of the third layer 12 is preferably chosen so as to underlie all of the absorbent pad. The patient transfer assembly preferably has handle means along its longest edges for ease of operation. In use the operator slides a patient placed on a disposable patient transfer assembly according to the present invention across surfaces by using the handle means. The handle means may for example be cut into or bonded or sewn to one or more of the layers and spaced conveniently along the longest edges of the patient transfer assembly. The underside of the third layer 12 may have, in addition or instead of these handles, channels incorporated therein for receiving stretcher poles in certain embodiments.

The first layer 10 may be formed from an acrylic, cellulosic or polyester polymeric material or mixtures thereof in the form of a non-woven or woven fabric with an optionally raised surface, which is non-linting and is soft and non-damaging to the patient's skin. The first layer 10 should have little, if any, liquid absorptive properties and should allow liquid such as blood etc. emanating from the patient to pass through the first layer 10 to the second layer 11. More specifically, the first layer 10, which has the function of permitting the passage of liquids and of being comfortable against the patient's skin. This first layer preferably comprises a non-woven, compressed spun polypropylene or polyester material. Alternatively the first layer may comprise a loop-raised warp-knit polyester of 50 dtex with 20 filament yarns, having 51 courses per inch (cpi) per 25 mm and 40 wales per inch (wpi) per 25 mm. Alternative materials with the desired characteristics are well known in the art and the materials specialist will select the optimum material for this application.

The technology associated with the manufacture of fabric and fabric composites having improved fluid absorbent properties, improved wickability and fluid retention properties is an ever advancing field of technology. It is intended that this disclosure, and this invention, should include the use of the optimum materials know today for the first, second and third layers as well as materials yet to be discovered.

Preferably the first layer 10 is resistant to tearing, liquid-permeable and may feel relatively dry to the touch even after liquid has passed through it. Preferably the first layer 10 is formed from a web of non-woven fibres such as acrylic, polypropylene or nylon/rayon and is substantially non-adherent to human skin when wet or dry, i.e. fluids rapidly pass through the first layer whilst retaining substantially no fluid on the surface.

Also preferably the side of first layer 10 that is intended to be in contact with the patient may comprise a pimpled surface thus increasing the sheet's surface area which will reduce the body surface area of the patient in contact with the sheet, thus reducing incidence of bed sores.

Preferably the first layer 10 contains few chemicals and more preferably is non-allergenic and capable of being sterilized by methods known in the art.

It is important to note that all of the layers, especially layer 10, are deemed to be non-allergenic, latex-free and odourless, and preferably biodegradable.

The second layer 11 is substantially absorbent and preferably comprises absorbent fibres such as non-woven polypropylene, tissue grade paper, cellulose wadding in the form of cotton or wood pulp fibres, rayon, polyester, cellulose fluff, absorbent cotton or similar material offering suitable liquid absorbent characteristics as would be determined by the materials specialist and includes materials yet to be developed. An absorbent gelling compound may be incorporated into the second layer 11. Such absorbent gelling compounds are known as water-insoluble hydrogels, they can be organic or inorganic, and swell on contact with liquids including water. Such hydrogels are found in diapers and feminine napkins and are used in conjunction with cellulosic type fibres to increase absorbency. Such hydrogels include silica gel and polymers such as polysaccharides. Certain hydrogels are termed super-absorbents that are capable of absorbing around 10 times their own weight, such superabsorbents are typically formed from an acrylic acid grafted onto a suitable carrier or cross-linked polymer. In an alternative the second layer 11 may be chemically treated to increase its absorptive properties, such treatments being well known in the art.

It will be understood that the choice of material or materials for the second, absorbent layer will be made by the appropriate materials specialist.

The second layer 11 may itself have a substantially liquid-resistant coating on the underside thereof so as to prevent transfer of liquids through to the third layer 12.

The third layer 12 is a preferably formed from a substantially fluid impermeable material. Preferably the co-efficient of friction of the third layer is low, and as such can easily move across a surface when a force is applied to the surface of the material. In a preferred embodiment the third layer comprises an non-woven, compressed polypropylene sheet. Alternatively in third layer may consist of a coated, warp-knit fabric, preferably polyester. The coating is preferably polyurethane to seal the warp-knit fabric to produce a membrane largely impermeable to body fluids to avoid soiling of the operating table surface.

In an alternative embodiment, the third layer 12 comprises a woven nylon fabric which has in particular high strength for coping with the mechanical loads applied to patients weighing up to 300kgs when being manoeuvred by nursing staff on the patient transfer assembly.

In a preferred embodiment the surface of the third layer 12 which is in contact with a surface in use is coated with a silicone elastomer to reduce friction between the third layer and the surfaces of the operating table or transferring board such as a Patslide.

This enables easier movement of a patient across a surface by nursing staff as the friction is reduced. Preferably the third layer 12 has a very low coefficient (0.05 to 0.6 and more preferably 0.1 to 0.5) of friction to facilitate easy sliding of the patient transfer assembly.

Friction is the force that opposes the relative motion or tendency of such motion of two surfaces in contact. In situations where the surfaces in contact are moving relative to each other, the friction between the two objects converts kinetic energy into sensitive energy, or heat.

The classical approximation of the force of friction known as Coulomb friction is expressed as: F1 = pR where p is the coefficient of friction, R is the reaction force normal to the contact surface, Ff is the maximum possible force exerted by friction.

This force is exerted in the direction opposite to the object's motion.

This law mathematically follows from the fact that contacting surfaces have close contacts only over extremely small fraction of their overall surface area, and this contact area is proportional to load.

The coefficient of friction (also known as the frictional coefficient) is a dimensionless scalar value which describes the ratio of the force of friction between two bodies and the force pressing them together.

Sliding (kinetic) friction and static friction are distinct concepts. For sliding friction, the force of friction does not vary with the area of contact between the two objects. This means that sliding friction does not depend on the size of the contact area.

Thus, to facilitate movement of a patient from one surface to another by means of a disposable patient transfers assembly a relatively low coefficient of friction in the underside of the third layer is desirable. As explained above, coefficients of between 0.05 and 0.6 are desirable, more preferably 0.1 to 0.5.

To reduce the coefficient of friction of the third layer 12, in one embodiment the underside of the third layer 12, that is to say the side intended to be in contact with the operating table, may comprise a pimpled surface which reduces the contact area of the third layer 12 with a surface as well as enhancing the cushioning effect of the softness of the sheet.

Alternatively, it may be desirable for the third layer 12 to have a high coefficient of friction to prevent the patient transfer assembly from moving around when used underneath a patient on, e.g. an operating table.

The third layer 12 may comprise a laminate of two or more laminate layers of fluid impermeable plastics material. In between the laminate layers there may be provided a mineral reinforced plastics material or other material as determined by the materials specialist, wherein when the laminate layers are sandwiched together with the mineral reinforced plastics material in-between the laminate layers moulded around the mineral reinforced plastics material to create the pimpled surface of the third layer 12.

Preferably the layers 10, 11, 12 are bonded together at their edges so that the fluid resistant properties of the third layer 12 are not compromised by stitching or other means of joining the layers. Most preferably the layers 10, 11, 12 are bonded together by adhesive or welding, including heat, laser or ultrasonically welding, or other such means which obviate the requirement for sewing/stitching.

In one embodiment the third layer 12 further includes a plurality handle means. The handle means may be in the form of holes or openings located along the longest edges of the patient transfer assembly as shown in Figure 2. The openings 30a-30f illustrated in Figure 3 are preferably longitudinal slots that are formed by portions of the third layer 12 which have been removed. A person may insert their hands or fingers through the openings 30a-30f to grasp the patient transfer assembly in use. Specifically, the slots essentially create a handle in the patient transfer assembly which provide a means to grasp or hold a patient transfer assembly and may have any desired shape or size and are not limited to the longitudinal slots 30a-30f shown in Figure 3. Additionally, the number of holes or openings may be chosen based on the size of the patent transfer assembly and the end user's needs.

In an alternative embodiment the patient transfer assembly may include a plurality of handles 40a-40f as gripping means as shown in Figure 4. The handles 40a-40f are strap handles made from a flexible and/or manipulable material. The straps may be formed from any flexible material that is sufficiently strong enough such that the strap will not break during lifting. Non-limiting examples of suitable materials for such straps include nylon or nylon products (e.g. woven nylon materials), a webbing of, for example, stitch white pre-shrunk terylene which are stitched or bonded onto the lower layer of the patent transfer assembly. Other suitable materials will be determined by the materials specialist. In the case of a strap handle 40a-40f, the handle is formed by attaching the ends of the material to the patient transfer assembly, such that a portion of the strap between the ends of the straps is not attached to the patient transfer assembly forming a loop. The unattached portion of the strap, when manipulated, provides a space between the surface of the patient transfer assembly and the underside of the strap through which a person may insert their fingers to take hold of the strap. Retention straps may also be used as the handle. In addition, each strap 51a-51f may be modified to include a crosspiece as shown in Figure 5 positioned approximately at 50mm from the corresponding edge of the sheet area. These crosspieces provide short straps for the patient transfer assembly which further enables the assembly to be used during say a fire evacuation.

Alternatively, the handles 20 may be made from more rigid materials, including but not limited to plastics, metals or the like as determined by the materials specialist as shown in Figure 2. The handles 20, 40a-40f, 51a-51f may be permanently attached to or detachable from the patient transfer assembly. Where a handle 20 is made from a rigid material it may be desirable to place some type of soft padding material around the handle. The use of such material would provide comfort to personnel handling the patient transfer assembly and also protect persons lying on the patient transfer assembly from the hard rigid handles. There is no limit, within reason, with respect to the size, shape or quantity of handles used on the patient transfer assembly.

Further, the location of the plurality of handle means to grasp the patient transfer assembly is not limited in any manner; e.g. a patient transfer assembly may provide both openings in the patient transfer assembly as gripping means for hands and nylon straps through which poles may be run to turn the patient transfer assembly into a stretcher. Preferably, the gripping means are located to provide for sufficient, uniform support of the person when the patient transfer assembly is lifted or moved.

The handles, whether attached or provided as openings, are such that ridges are avoided underneath the absorbent pad which could give rise to sites of local pressure and abrasion and also avoids compromising the liquid resistant properties of the absorbent pad.

In an alternative embodiment, each handle or strap has stitched to the end most distant from the edge of the assembly from which is extends a strip of hook and loop fastener material 41a-f, 52a-f, such as VelcroTM, and a corresponding strip of hook and loop fastener material is secured to an edge portion of the underside of the lower layer, as shown in Figures 4 and 5. The provision of a hook and loop fastener for each handle enables the handles to be tidied away by attaching the hook and loop material at the free ends of the handles to the underside of the lower layer once the patient has been transferred. This removes the danger of objects becoming snagged in the handles when the handles are not in use, which is of particular concern in an operating theatre

for example.

In a further embodiment shown in Figure 52 to 54 the handles are loops 170 which run the full width of the patient transfer assembly and are welded onto the underside of the third layer. In an alternative the loops 170 may be welded in between layers or on top of the first layer, although these options are not currently preferred.

In a particularly preferred embodiment of the present invention as shown in Figures 9 and 10 the third layer comprises two or more layers 13, 14 of the plastics material previously described. The two or more layers 13, 14 are bonded together by, for example, adhesive or welding such as heat, laser or ultrasonic welding to form a plurality of passageways 15, 16 or air channels under the patient continuously linked across the area of the third layer 12. Preferably there are wide passageways 90a, 90b, lOOa, lOOb created along the longest edges with smaller passageways 91, 101 created therefrom connecting the two larger channels. One of the larger air passageways 91 b, lOIb is adapted to be connected to an air blower 92, 102. When air is blown into the first larger passageway, the passageways are so linked that the air can fill all of the passageways created. Preferably hot or warm air is blown into the passageways which creates warmth beneath the patient lying on the patient transfer assembly. A porous region or regions may be incorporated towards but not limited to the lateral aspects of the transfer sheet, which allows the hot air out intermittently to ease off the pressure built up in the passageways. In an alternative embodiment cold air can be blown through the passageways to cool the patient.

Where the third or lowermost-in-use layer is formed from two or more sheets of material, as shown in Figures 1, 9 or 10, the upper of these sheets may contain perforations or micro-perforations in order to allow the conditioned air to escape around the patient. The perforations may be located in strategic positions or distributed uniformly across the surface area of the patient transfer assembly.

In one preferred embodiment these perforations or vents through which conditioned air can escape are located along each long side of the transfer assembly. That is to say, the perforations are to the side of the region containing the absorbent layer. During an operation the patient is generally covered with sheets which hang down on either side of the patient. Under the arrangement described above, conditioned air escapes within the confines of these sheets and keeps the patient warm or cool as required.

Patient comfort systems in the form of pneumatic warming blankets are known per se.

One such system is the so-called BAIR HUGGER (RTM) produced by Arizant Healthcare Inc of Praire, MN 55344, USA. W003/086500 (Arizant Healthcare Inc) is one patent application which describes this technology in the form of a garment, the entire text of which is incorporated herein by reference and is intended to form an

integral part of this disclosure.

Thus, in the present assembly there may be provided a pneumatic convective device which receives a stream of pressurized, thermally conditioned air, distributes the pressurized air within a pneumatic structure, and emits the air through one or more surfaces for convective transfer of heat between the thermally conditioned air and the body. This enables a human or animal body to be warmed by focusing or concentrating convective warming on the body core.

Further, use of the term "convective" to denote the transfer of heat to a body refers to the principal mode of heat transfer, it being understood that heat may at the same time be transferred between an assembly according to this invention and a body by conduction and radiation, although not to the degree of convection. In essence, conditioned air is forced into a series of passageways under pneumatic pressure, the passageways being adapted to receive and distribute that air. The conditioned air is then emitted from the passageways through an air permeable sheet.

In an alternative embodiment the lower layer comprises two layers 13, 14 of the plastics material previously described. In between the two layers 13, 14 is located preformed tubing 111, preferably formed of a plastics material and even more preferably having located within the tubing a mechanism 112a, b, c which prevents total collapse of the tube when pressure is applied to the outside of the tube, as shown in Figure 11. Such tubes are known per se and can be found for example in oxygen supply tubes such as those supplied by Intersurgical Ltd and Salter Science Ltd. Such a mechanism comprises splines 112a, b, c located longitudinally along the internal walls of the tubing. When an external force is applied to the outer wall of the tubing the splines come into contact with each other and support each other from further collapse.

Thus the tube may be partially collapsed but there are still passageways for the fluid to pass through and the supply is not totally blocked. In this way the passageways are always available and there is no need to disturb the patient or to interrupt an operation to begin passing fluid through the passageways. The fluid is preferably conditioned and may be water or air for example.

In a further embodiment the preformed tube may take the form shown in Figure 1 1A.

In this embodiment the tubing 115 contains a series of discrete channels running the length of the tubing. The varying wall thicknesses, and in particular the varying thicknesses of walls I 16a, b and c means that, even under the weight of a patient, some passageway for distributed air is always present.

The patient transfer assembly may be modified to include a foot pocket (not shown) at one end thereof to enable the assembly to be used in the transfer of patients down stairs or ladders during say a fire evacuation.

In a further embodiment the patient transfer assembly may further comprise an insulating hood 112 as shown in Figure 12. The insulating hood 112 is attached to the patient transfer assembly at the patient's head end of the patient transfer assembly.

The insulating hood 112 is then drawn up around the patient's head leaving the face area open. This is particularly useful during use in an operating theatre so that heat is not lost out of the patient's head. The insulating hood 112 may further comprise a fastening means to enclose the insulating hood to be kept in place around the patient's head.

In a still further preferred embodiment the patient transfer assembly further includes arm restraint means, such that when the patient transfer assembly is used under the patient as, for example, an operating table, the arms can be conveniently restrained in a desired position.

Figure 6 shows one type of arm restraint means where rigid or semi-rigid support bars 60a, 60b fold up from the patient transfer assembly to a desired angle which support the patient's arms. Preferably the rigid or semi-rigid support bars are covered with a soft material to cushion the patient's elbow and/or arm.

Figure 7 shows an alternative arm restraint means where straps 70a, 70b are located on opposite edges of the patient transfer assembly, preferably the straps are adjustable 71a, 71b for the patient. The straps have a ring 72a, 72b made of a soft material which fits around the elbow of a patient when the patient's arms and/or forearms are placed for example over the patient's chest. The free ends of the straps are provided with a fastening means 73a, 73b such that the straps can be fastened together restraining the patient's arms in a comfortable position while leaving the arms and/or forearms exposed for, e.g. intravenous insertion of lines. Preferably the ends of the restraint means are provided with corresponding hook and loop fastening material, such as VelcroTM, and a corresponding strip of burr fastener material is secured to an edge portion of the underside of the lower layer. The provision of a burr fastener on each restraint means has the added advantage of fastening the restraint means together in use and allows the restraint means to be tidied away by fastening to the burrs located underside when not in use. Alternatively each free end may be provided with a single hook, the hooks connecting with each other to restrain the patient' arm and/or forearms onto the chest or side of the patient.

Figure 8 shows a further alternative arm restraint means where foam padded blocks 80a, 80b are provided on opposite edges of the patient transfer assembly. The foam-padded blocks retain the patient's elbows without significant nerve pressure.

Figures 22 to 26 show a further alternative arm restraint means 150, 151 which is a lower arm restraint for restraining the patient's arms in a position beside the body of the patient. The arm restrain means 150, 151 are simply formed from a soft padded flexible optionally foam material with a hook and loop fastener arrangement to secure the arm restraint means, and thus the patient's arms in position. In this further embodiment leg restraint means 152, 153 are also provided which are similar to the arm restraint means, being formed from a soft padded flexible optionally foam material with a hook and loop fastener arrangement to secure the leg restraint means, and thus the patient's legs in position.

Figures 28 to 33 show a further alternative arm restraint means 154. This arm restraint means 154 follows the same principles as the arm restraint shown in Figure 7, wherein the patient's arms are crossed across the chest and held in position by locating the patient's elbows in loops 155, 156 provided in the arm restraint. In this embodiment the arm restraint means is formed from a soft padded foam material with a hook and loop fastener arrangement to secure the arm restraint means 154 to the patient transfer assembly, the arm restraint means 154 being completely removable from the patient transfer assembly if desired. The loops 155,156 may be formed by a substantially continuous piece of material formed into a loop and held together at or near its mid-point to form two loops, one for each elbow.

In a further alternative there may be provided a plurality of arm restraint means on each side of the patient transfer assembly in order to restrain arms of different lengths or to restrain each arm more than once in different positions along the arm, In a further embodiment the patient transfer assembly includes areas of pressure relieving material 140, 141, 142, 143, 144, 145, 146 as shown in Figure 21. Pressure ulcers are areas of damage to the skin and underlying tissue, usually occurring over bony prominences.

They are caused by: * pressure: occurs when skin and tissue are directly compressed between bone and a support surface such as a bed or wheelchair. Blood is unable to circulate causing a decrease of oxygen and nutrients to the underlying cells; * shear: occurs when skin and tissue are pulled in different directions, for example when a person slips down a bed or is repositioned using a dragging motion; * friction: occurs when the skin rubs against a surface, for example the heels rubbing against a sheet..

The greatest areas at risk are those where there are weight bearing bones near the surface of the skin, for example under the bones in the buttocks -the ischial tuberosities. The shoulders, hips and heels are also at increased risk.

An area of pressure relieving material is provided for the head 140, shoulders, 141, 142, buttocks and hips 143, 144 and heels 145, 146.

In one embodiment the pressure relieving material is formed from air alternating cushions. These are made of rows of air cells which inflate and deflate alternately or sequentially for a pre-set time period. This ensures that the pressure on any given point is changing continually, so that the pressure is completely removed from that point for a short period of time.

In an alternative embodiment the pressure relieving material is formed from a static air cushion. The pressure relieving properties of these cushions and overlays relies on the fact that they are air filled. Air is channelled within these cushions via air-filled balloons or pathways. The balloon type increases the surface area over which the pressure is distributed. The pathways help the air to circulate and to disperse the heat and moisture.

In a further alternative embodiment the pressure relieving material is formed from a foam. The foam may be in one alternative a single or varied density foam. In an alternative the foam may be cross cut, contoured or convoluted. Cross cut, contoured and convoluted foam allows greater conformity and can reduce friction and shear by allowing the surface to move with the user. They also provide greater ventilation for the skin than other foams, as flat surfaced foam can act as an insulator and increase skin temperature. In a further alternative the foam may be a memory foam. Heat sensitive or conforming foam with slow memory release models the shape of the body better than standard foam. The slower conforming properties of this material may enhance stability.

In a further alternative embodiment the pressure relieving material is formed from a gel.

Gel cushions work on the principle that the weight of the user is distributed over the liquid or solid gel. The gel is able to conform to the body shape, so that the pressure is distributed over the whole area. Gel is able to conduct heat away from the user so that the cushion is cool.

In a further alternative embodiment the pressure relieving material is formed from a water cushion. However, water cushions can be less stable than gel (although more stable than air) and so do not provide much postural support. They are heavy to move and, if punctured, the rapid loss of contents may cause a problem. They are not stable, especially when the user is transferring, unless the flow of water can be reduced by enclosing it in multiple compartments.

In the embodiments of the patient transfer assembly shown in Figures 22 to 33 there are provided a number of areas of pressure relieving material. There is a moulded head and neck support 157 which is shown in more detail in Figures 47 to 51. There are two shoulder supports 158, 159 one of which is shown in more detail in Figures 39 to 41. There is a back support 160 which is shown in more detail in Figures 34 to 38.

Finally there is a foot support 161 which is shown in more detail in Figures 42 to 46.

The head and neck support 157 shown in Figures 47 to 51 is designed to support the neck in the neck support recess 162 and the back of the head in the head support recess 163, keeping the head in such a position that the airway remains open and unobstructed by parts of the patient's own body. To the sides of the neck support recess 162 are raised portions 164, 165 which support the sides of the neck and prevent side to side movement of the patient's head.

The pressure relieving material is preferably a closed cell polymeric material such as polyester foam, but other materials may be used as determined by the materials specialist.

In one embodiment the pressure relieving material is mounted onto the surface of the first layer of the patient transfer assembly. In an alternative embodiment the pressure relieving material is mounted under the first layer of the patient transfer assembly and the first layer mounted to cover the full surface of the patient transfer assembly as shown in more detail in the cutaway section in Figure 32, where the first layer 166 covers the pressure relieving material which are mounted on an under layer 167. A similar arrangement is also shown in Figures 24 and 25.

It will be appreciated that the pressure relieving material pads or portions can be located at any desired location on top of, within, or even under, the disposable patient transfer assembly. Locating them on the outer face of the first or uppermost-in-use layer has the advantage that it is relatively easy to make versions of the product both with and without pressure relieving material.

In a preferred embodiment the layers are bonded together using an adhesive across the full area of the patient transfer assembly and as well as or in the alternative bonded around the edges of the patient transfer assembly using adhesive or heat, laser or ultrasonic welding. In a particular preferred embodiment the third layer is folded over the first layer such that the third layer overlaps the first layer and the layers are sealed along the overlapping edges so formed, an example of which can be found in Figure 53. Thus, a welded edge can be formed along substantially the whole length of all four edges where the assembly is rectangle.

In one embodiment the patient transfer assembly is of integral construction for example the layers, fluid passageways, handle means, arm restraint means, hood, pressure relieving material etc may be formed integrally rather than as separate units.

It will readily be appreciated that the individual aspects of the embodiments described may be used alone or in any combination with each other, for example the layers may be used in conjunction with the handles alone or in addition with the fluid passageways.

Alternatively for example the layers may be used with the arm restraint means alone or in addition with a hood. Further alternatively for example the layers may be used with the pressure relieving material alone or in addition with the handles etc. In effect, the various optional features are just that, optional, and can be used and incorporated independently of each other.

The invention may comprise all the embodiments described and have layers, handles, fluid passageways, pressure relieving material, arm restraint means, and a hood and a foot pocket.

An example of a method of manufacturing the patient transfer assembly can be seen in part in Figures 52 to 54 wherein the handles 170 are welded onto the underside of the third layer 173, wherein the first and second layers 172 are placed onto the third layer and wherein the third layer is larger than the first and second layers, and the edges of the third layer are folded over the top of the first and second layers and welded to secure the construction. In this example the first and second layers are formed as an integral padded sheet.

According to a further aspect of the present invention, there is provided a disposable mat for placing on the floor around an operating table. Referring now to Figures 13 and 14, which show cross-sections of such a mat comprising a first or uppermost-in-use layer 131 of substantially fluid permeable material. There is then provided a second or intermediate layer 132 of a liquid absorbent material and finally a third or lowermost-in-use layer 133 of substantially fluid impermeable material. In the particularly preferred embodiment of Figure 4 a fourth layer 134 is provided comprising an adhesive material.

The terms "uppermost-in-use layer" and "lowermost-in-use layer" refer to the position of the layers when used as a mat on the floor around an operating table for example.

Preferably the first 131 and second 132 layers form an absorbent pad and preferably the absorbent pad is of sufficient length and width to underlie the floor surrounding an operating table. The size of the third layer 133 is preferably chosen so as to underlie the entire absorbent pad.

The layers in this aspect of the invention may be the same or similar to the respective layers described above. For example, the first layer 131 may be a synthetic polyester knitted fabric with a raised surface which is non-linting. The first layer should have little, if any, liquid absorptive properties and should allow liquid such as blood and body fluids etc. emanating from the patient on the operating table and dripping onto the floor to pass through the first layer 131 to the second layer 132. More specifically, the first layer 131, which has the function of permitting the passage of liquids, preferably comprises a loop-raised warp-knit polyester of 50 dtex with 20 filament yarns, having 51 courses per inch (cpi) per 25 mm and 40 wales per inch (wpi) per 25 mm.

Alternative materials with the desired characteristics are well known in the art and the optimum material for this application will be selected by the materials specialist.

Preferably the first layer 131 is resistant to tearing, liquid-permeable and may feel relatively dry to the touch even after liquid has passed through. Preferably the first layer 131 is formed from a nylon/rayon web of non-woven fibres and is substantially non-adherent to human skin when wet or dry, i.e. fluids rapidly pass through the first layer 131 whilst retaining substantially no fluid on the surface.

Preferably the first layer 131 has few chemicals and more preferably is hypoallergenic and capable of being sterilized by methods known in the art.

The second layer 132 is substantially absorbent and preferably comprises absorbent fibres such as tissue grade paper, cellulose wadding in the form of cotton or wood pulp fibres, rayon, polyester, cellulose fluff, absorbent cotton or similar material offering suitable fluid absorbent characteristics as would be determined by the materials specialist and includes materials yet to be developed. An absorbent gelling compound may be incorporated into the second layer. Such absorbent gelling compounds are know as water-insoluble hydro-gels, they can be organic or inorganic, and swell on contact with liquids including water. Such hydro-gels are found in diapers and feminine napkins and are used in conjunction with cellulose type fibres to increase absorbency.

Such hydro-gels include silica gel and polymers such as polysaccharides. Certain hydro-gels are termed super absorbents which are capable of absorbing around 10 times their own weight, such super absorbents are typically formed from an acrylic acid grafted onto a suitable carrier or cross-linked polymer. In an alternative the intermediate layer may be chemically treated to increase its absorptive properties, such treatments are well known in the art.

The second layer 132 may itself have a substantially liquid-resistant coating on the underside thereof so as to prevent transfer of liquids through to the third layer 133.

The third layer 133 is a preferably formed from a substantially fluid impermeable material. In a preferred embodiment the third layer 133 comprises a coated, warp-knit fabric, preferably polyester. The coating is preferably polyurethane to seal the warp-knit fabric to produce membrane largely impermeable to body fluids.

In an alternative embodiment, the third layer 133 comprises a woven nylon fabric which has in particular high strength for coping with the mechanical loads applied to the mat when being walked on by the staff in the operating theatre.

Preferably the third layer 133 has a high coefficient of friction to prevent the mat from moving around when being walked on by the staff in the operating theatre.

In addition, the mat is preferably provided with a fourth layer 134 as shown in Figure 14 of an adhesive. Preferably the adhesive is pre-applied to the mat which may have a protective backing sheet placed there over which is removed prior to use. The adhesive should be capable of adhering the mat to the floor during use, whilst allowing the mat to be readily removed from the floor after an operation for disposal. Suitable adhesives are to be determined by the materials specialist. Alternatively the adhesive may be applied to the mat prior to use for example a low tack spray adhesive used for mounting carpet tiles and spray mounting pictures and the like.

In an alternative embodiment the fourth layer 134 may be a "sticky" polymer capable of adhering to surfaces such as the polymer used in mats used in cars for "holding" mobile phones and the like.

Examples of how such a mat or mats may be used in practice are shown in Figures 15 to 20 inclusive. In Figure 15 a U-shaped mat is shown positioned around one end of an operating table for pelvic, urological, lower limb, gynaecological and obstetric operations and procedures. In Figure 16 a U-shaped mat is shown positioned around the opposite end of an operating table for thoraco-abdominal operations and procedures including cardiac surgery. Figure 17 shows a different shape of U-shaped mat designed for head, neck, ophthalmic and neurosurgical operations and procedures. Figures 18, 19 and 20 show how a series of rectangular mats can be placed around the base of an operating table to cover a wide variety of operative procedures.

Once an operation has been completed the mat or mats are rolled or folded up, soiled side inwards, and are sent for disposal.

!ieflo Fiures Figure 1 -layer 1, one way permeable sheet 11 -layer 2, moisture retaining layer 12 -layer 3 & 4. Plastic sheets welded/bonded to form air channels Figure 2 Handles 20 welded, glued or stitched onto laminate layers or onto supporting straps Figure 6 Rigid supoprt bars 60a, 60b fold up to 45 degrees to support the patient's arm. Soft material is fitted around support bars 60a, 60b to cushion the patient.

Figure 7 Hook 73a, 73b connects to ring 71a, 71b to retain arm. Long straps 70a, 70b allow adjustment up and down. Soft ring 72a, 72b fits around patients elbow.

Figure 8 Foam padded blocks 80a, SOb to retain the patients elbows without nerve pressure.

Figure 9 2 waterproof plastic layers bonded/welded to form air channels under the patient.

Large tubes 90a, 90b formed between layers. Small tubes 91 formed between layers.

Hose 92 to air blower. 0***

. Figure 10 2 waterproof plastic layers bonded/welded to form air channels under the patient.

C': Large tubes bOa, lOOb formed between layers. Small tubes 101 formed between layers. Hose 102 to air blower.

Figure 12 *: Insulating hood 122 attached to sheet is pulled up around patient's head leaving face :::. open.

Figure 13 131 -layer 1, one way permeable sheet 132 -layer 2, moisture retaining layer 133 -layer 3, plastic sheet Figure 14 131 -layer 1, one way permeable sheet 132-layer 2, moisture retaining layer 133 -layer 3, plastic sheet 134 -layer 4, adhesive Figure 15 U-Mat, for pelvic, uorological, lower limb, gynaecological and obsetric operations and procedures.

Figure 16 U-Mat, for thoraco-abdominal operations and procedures including cardiac surgery.

Figure 17 U-Mat, for head, neck, opthalmic and neurosurgical operations and procedures.

Figure 52 172 -double layer padded sheet 173 -heavy duty support sheet/barrier layer 170-handles welded on underside.

Figure 53 Bottom support layer wraps over top layer on all 4 edges, weld along full length on 4 edges. 200-top sheet, 201 -bottom sheet, 202 -weld.

Figure 54 View from underside, 203 -welds, 170 -strap handles, 201 -heavy duty support sheet. *0' * S S S. S * .55 * S * S55 5... * S * * S 55.

S S... S. * S * I I *I

Claims

CLAIMS: 1. A disposable patient transfer assembly comprising a first or uppermost-in-use layer, a second or intermediate layer and a third or lowermost-in-use layer, wherein said first layer is adapted to minimise the damage to a patient's skin when disposed against the skin of a patient, said second layer is liquid absorbent and said third layer is adapted to be substantially impermeable to the passage of fluids, further comprising an arm restraint means.
2. A disposable patient transfer assembly as claimed in Claims I wherein the arm restraint means comprises elbow restraints.
3. A disposable patient transfer assembly as claimed in Claim 2 wherein the arm restraint means comprises a first strap incorporating a ring or loop adapted to fit around the elbow of a patient.
4. A disposable patient transfer assembly as claimed in Claim 3 wherein the arm restraint means further comprises a second strap incorporating a ring or loop adapted to fit around the elbow of a patient.
5. A disposable patient transfer assembly as claimed in Claim 4 wherein the first and second straps are provided with a fastening means for holding the arm in the desired position.
6. A disposable patient transfer assembly as claimed in any of Claims 3 to 5 wherein the ring or loop is formed of a material adapted to minimise damage to the patient.
7. A disposable patient transfer assembly as claimed in any of Claims 4 to 6 wherein the first strap is integral with the second strap
8. A disposable patient transfer assembly as claimed in any of the preceding claims further comprising handle means.
9. A disposable patient transfer assembly as claimed in Claim 8 wherein the handle means comprise a plurality of straps provided along at least one edge of the patient transfer assembly.
10. A disposable patient transfer assembly as claimed in Claim 9 wherein the straps are formed of a flexible material.
11. A disposable patient transfer assembly as claimed in Claim 9 or Claim 10 wherein the straps are provided with a fastening means for securing the straps away when not in use.
12. A disposable patient transfer assembly as claimed in any preceding claim further comprising at least one area of pressure relieving material
13. A disposable patient transfer assembly comprising a first or uppermost-in-use layer, a second or intermediate layer and a third or lowermost-in-use layer, wherein said first layer is adapted to minimise the damage to a patient's skin when disposed against the skin of a patient, said second layer is liquid absorbent and said third layer is adapted to be substantially impermeable to the passage of fluids, further comprising at least one area of pressure relieving material.
14. A disposable patient transfer assembly as claimed in Claim 12 or Claim 13 wherein the pressure relieving material is formed from an air alternating cushion.
15. A disposable patient transfer assembly as claimed in Claim 12 or Claim 13 wherein the pressure relieving material is formed from a static air cushion.
16. A disposable patient transfer assembly as claimed in Claim 12 or Claim 13 wherein the pressure relieving material is formed from a foam.
17. A disposable patient transfer assembly as claimed in Claim 16 wherein the foam is a memory foam.
18. A disposable patient transfer assembly as claimed in Claim 12 or Claim 13 wherein the pressure relieving material is formed from a gel cushion.
19. A disposable patient transfer assembly as claimed in Claim 12 or Claim 13 wherein the pressure relieving material is formed from a water cushion.
20. A disposable patient transfer assembly as claimed in any of Claims 12 to 19 wherein the areas of pressure relieving material are located at the head area and/or shoulder areas and/or back area and/or foot area.
21. A disposable patient transfer assembly as claimed in any of claims 12 to 19 wherein the pressure relieving material located at the head area has a neck recess and/or a head recess.
22. A disposable patient transfer assembly as claimed in any preceding claim further comprising a passageway adapted to circulate temperature conditioned fluid within the patient transfer assembly.
23. A disposable patient transfer assembly comprising a first or uppermost-in-use layer, a second or intermediate layer and a third or lowermost-in-use layer, wherein said first layer is adapted to minimise the damage to a patient's skin when disposed against the skin of a patient, said second layer is liquid absorbent and said third layer is adapted to be substantially impermeable to the passage of fluids, further comprising areas of pressure relieving material, further comprising a passageway adapted to circulate temperature conditioned fluid within the patient transfer assembly
24. A disposable patient transfer assembly as claimed in Claim 22 or Claim 23 wherein the third layer is formed from a laminate comprising two sheets of material and wherein the two sheets of material are bonded together so as to form a passageway adapted to circulate temperature conditioned fluid within the patient transfer assembly.
25. A disposable patient transfer assembly as claimed in Claim 22 or Claim 23 wherein the passageway is provided by a pre-formed tube.
26. A disposable patient transfer assembly a as claimed in Claim 22 or Claim 23 wherein the passageway is provided by a built-in tube.
27. A disposable patient transfer assembly as claimed in any of Claims 22 to 26 wherein the passageway is provided with a mechanism to prevent total collapse of the passageways in use, under the body weight of a patient.
28. A disposable patient transfer assembly as claimed in Claim 27 wherein the passageway is provided with an internal spline extending along the longitudinal axis of the passageway.
29. A disposable patient transfer assembly as claimed in any of Claims 22 to 28 wherein the passageway is adapted to be connected in use to an air blower.
30. A disposable patient transfer assembly as claimed in any of Claims 22 to 29 wherein the passageway incorporates a vent to allow air to exit the passageway in a controlled manner.
31. A disposable patient transfer assembly as claimed in any of the preceding claims further comprising an insulating hood.
32. A disposable patient transfer assembly as claimed in any preceding claim wherein the assembly further comprises a fastening means for securing the legs of the patient.
33. A disposable patient transfer assembly as claimed in any preceding claim wherein the first, second and third layers are bonded together around the edges of the patient transfer assembly.
34. A disposable patient transfer assembly as claimed in Claim 33 wherein the layers are bonded together using ultrasonic welding.
35. A disposable patient transfer assembly as claimed in any preceding claim wherein the first layer is formed from a non-woven material
36. A disposable patient transfer assembly substantially as herein before described with reference to Figures Ito 12 and 21 to 54 inclusive.
37. A method of manufacturing a disposable patient transfer assembly comprising the steps of: g) providing a layer of liquid impermeable material; h) providing a layer of liquid absorbent material; i) providing a layer of liquid permeable material; j) arranging the layer of liquid absorbent material onto the layer of liquid impermeable material; k) arranging the layer of permeable material onto the layer of liquid absorbent material; and I) bonding the layers together
38. A method of manufacturing a disposable patient transfer assembly as claimed in Claim 37 wherein the method of bonding is ultrasonic welding.
39. A method of manufacturing a disposable patient transfer assembly as claimed in Claim 37 or Claim 38 wherein the layer of liquid impermeable material is folded over at least one of the edges of the layer of liquid permeable material and bonding takes place in the overlapping region.
40. A method of manufacturing a disposable patient transfer assembly as claimed in any of claims 37 to 39 wherein there is provided a layer of adhesive between each of the layers.
41. A method of manufacturing a disposable patient transfer assembly as claimed in any of claims 37 to 40 further comprising bonding handles to the layer of liquid impermeable material.
42. A method of manufacturing a disposable patient transfer assembly as claimed in Claim 41 wherein the bonding is ultrasonic welding.
43. A disposable mat assembly comprising a first or uppermost-in-use layer, a second or intermediate layer and a third or lowermost-in-use layer, wherein said first layer is adapted to be resistant to tearing when walked on and is substantially fluid permeable, said second layer is liquid absorbent and said third layer is adapted to be substantially impermeable to the passage of fluids. wherein said assembly comprises a fourth layer comprising an adhesive layer, preferably a low-tack adhesive layer.
44. A disposable mat assembly substantially as herein described with reference to and as illustrated in any combination of Figures 13 to 20 inclusive.
45. A method of manufacturing a disposable patient transfer assembly or disposable mat assembly substantially as herein described with reference to and as illustrated in any combination of Figures.