Claims:
I claim
1. A mattress comprising: a block of resilient material for supporting a patient and on top of the block aeration means comprising a lower sheet and an upper sheet attached together to define chambers containing pieces of resilient foamed plastics material, the lower sheet being air impermeable and the upper sheet being air permeable, and air supply means for supplying conditioned air to the chambers to issue from the top sheet to impinge on and pass around a patient lying on the mattress.
2. A mattress as claimed in claim 1, wherein the panels are attached to each other by seams dividing the aeration means into a plurality of interconnected ribs, each rib having a spine of resilient plastics material extending therealong, each spine being narrower than the rib in which it is disposed.
3. A mattress as claimed in claim 2, wherein the aeration means has side ribs which are larger than the aforementioned ribs and which contain air supply tubes and serve to locate the aeration means on the block.
4. A mattress as claimed in claim 2, wherein the seams are discontinuous to allow air to flow from rib to rib.
5. A mattress as claimed in claim 1, in combination with a cover in the form of a bag having an air permeable upper surface which may protect the mattress from contamination by a patient but still allow air from the mattress to reach the patient.
Description:
This invention relates to a mattress, particularly but not exclusively, for use in the treatment and resuscitation of patients in hospital, or at home.
In order to resuscitate a patient after extensive surgery it is desirable that the body be enclosed in a microclimate, that is an environment containing conditioned air. This air may be bacteria-free and have its temperature and humidity controlled to prevent excessive metabolisation and remove strain from the patient's heart, or alternatively, accelerate healing of, for instance burns.
It is an object of the present invention to provide a mattress whereon a patient, suffering, for instance, from shock, hypothermia or burns, can be supported and his body, which may be covered by a sheet, exposed to a microclimate of conditioned air to encourage resuscitation, which is relatively cheap to manufacture and which does not require a very large air supply. It is desirable that free flow of this air is not hindered or stopped by compression of the mattress by the weight of the patient supported thereby.
Accordingly the invention provides a mattress comprising a lower panel of air-impermeable material, an upper panel and means for supplying air to the space between the panels, the upper panel having at least part of its area perforate and provided with apertures whence conditioned air from the said space can issue and so impinge on and pass around a patient lying on the mattress.
The upper panel can be of air permeable material, and thus be effectively perforate over its entire surface or can be of an air impermeable material and have a central area thereof provided with apertures to render it air permeable.
By "conditioned air" is meant air which may be bacteria-free and of a predetermined temperature and humidity.
Preferably the panels are generally rectangular and attached to each other along lines parallel to the longitudinal edges of the panels so as to divide up the interior of the mattress into a plurality of inter-connected ribs.
Advantageously, the ribs comprise two pairs of side ribs and one or two end ribs, disposed beneath the imperforate peripheral border of the top panel, and a plurality of longitudinally extending central ribs disposed beneath the central area of the top panel.
Conveniently, and to prevent the weight of a patient from collapsing any of the central ribs completely, each central rib has a spine of resilient material therein. Each such spine can extend centrally of each central rib and so divide the rib into two air supply channels along which air can pass even when the spine is compressed by the weight of a patient.
The supply means can comprise a header manifold, disposed parallel to but outside one end rib, or inside an end rib, and connected to a supply of conditioned air, and two supply tubes, connected to the manifold and one extending inside one of each pair of side ribs of the mattress. When the manifold is disposed outside the mattress a slot is provided at each end of the said one end rib to allow easy entry of the tubes. Each tube has its end remote from the header open, if a second end rib is provided, for supplying air to the other end rib, and an aperture adjacent its manifold end for supplying air to the one end rib.
Each tube is conveniently of foamed plastics material and extends along an outer one of the respective pair of side ribs. Each inner side rib can accommodate a resilient foam plastics cushioning tube.
The side ribs are advantageously deeper than the central ribs so that a recess is defined thereby beneath the central ribs, this recess accommodating a resilient foam plastics material block. The whole mattress can comprise an outer cover of air permeable textile material such as cambric.
The invention will be described further, by way of example, with reference to the accompanying drawings, wherein :
FIG. 1 is a perspective view, from above, of a preferred embodiment of mattress conforming to the invention; and
FIG. 2 is a cross-section, on an enlarged scale, taken on the line II--II of FIG. 1.
A preferred embodiment of mattress 9 conforming to the invention comprises upper and lower generally rectangular panels 10 and 11 of flexible synthetic plastics material. The panels are attached to, around their peripheries, for example by being integral or by being welded or sewn. The panels 10 and 11 are attached together by a plurality of longitudinally extending parallel seams, 12, each of the seams 12 extending from a position near to but spaced apart from one end of the mattress 9 to a position near to but spaced from the other end of the mattress 9. It will thus be appreciated that the seams 12 divide the mattress 10 into two pairs of longitudinally extending side ribs 13, 14 and 15, 16 and a plurality of longitudinally extending central ribs 17. The panel has an end rib 18 and its other end 19 is generally flat. That peripheral portion of the upper panel 10 which is above end rib 18, and part 19 and side ribs 13, 14, 15, 16 is imperforate, as is the entire lower panel 11, but a central area 20 of the upper panel 10 above the central ribs 17 is provided with a plurality of apertures 21 for a purpose which will be described later.
The end portion 19 and the other end portion adjacent are provided with strips 26 of hook and pile material secured thereto to facilitate attachment of the mattress 9 to a support, such as a bed, having complementary strips.
Centrally and longitudinally of each central rib 17 extends a spine 22 of foamed plastics material, each spine 22 being of thickness equal to about that thickness which the central ribs 17 would assume if the mattress 9 was inflated.
Supply means of the mattress comprises a header manifold (not shown) of length equal to about the width of the mattress 10 and disposed inside end rib 18. An end portion 23 of the manifold protrudes from one end of end rib 18. A pair of supply tubes 24, 25 of resilient foam plastics material, extend at right angles from the manifold and are disposed inside side ribs 13 and 16. Resilient foam plastics material cushioning tubes 27, 28 extend along side ribs 14 and 15.
The side ribs 13, 14, 15, 16 are deeper than the ribs 17 and a recess is thus defined beneath ribs 17 which can accommodate a block 33 of resilient foamed plastics material as an extra support for a patient on the mattress.
The tubes 24, 25 have their open free ends disposed adjacent end portion 19 of the mattress, for supplying air thereto, and has an aperture close to but spaced from its manifold end for supplying air to the one end rib. The manifold is, in use, connected to a supply of conditioned air, that is air which has its temperature and humidity controlled and which may be bacteria free.
When a patient is supported by the mattress 9 and the supply of conditioned air switched on, air issues from the apertures 21 in the ribs 17 and ensures a plentiful supply of air to the patient's body. Although the weight of the patient may tend to compress the ribs 17 the spines 22 of foamed plastics material ensure, even when they are fully compressed, that air channels 29 exist on each side of the spines 22 so that air can still reach the patient. The supply of air required is about 50 cubic feet of air per minute.
In order that the mattress 9 is not contaminated by the patient the mattress 9 is surrounded by an air-permeable mattress cover 30. This cover 30 is in the form of a rectangular bag, an upper surface 31 of which is made from fine mesh so as to be readily permeable to air issuing from the apertures 21 in the mattress 10, and the lower surface 32 which is of a less permeable woven textile material. The cover 30 protects the mattress 9 against contamination by the patient but still allows air from the mattress 9 to contact and flow around his body.
The invention is not limited to the precise details of the foregoing description and variations can be made thereto within the scope of the following claims. For example the configuration of the ribs need not be as described and can be varied as desired into any practical arrangement. The mattress need not comprise ribs but could have a plurality of interconnected cells or pockets. The mattress can be made from any air-impervious material such as close-woven textile material or plastic.
As an alternative the upper panel can be made from air-permeable material, for example a textile material and thus be effectively perforate over its entire area.
The supply means need not be as described and the manifold can be disposed outside and parallel to rib 18, a pair of slits in rib 18 allowing tubes 24, 25 to enter the side ribs 13, 16. The supply means can comprise a plurality of air supply tubes connecting with various points on the periphery or underside of the mattress. The seams 12 can have gaps therein to allow air to pass more easily from tubes 24, 25 to ribs 17.
The spines need not be continuous and each can comprise a plurality of discrete portions of material spaced apart along each rib. Many other variations are, of course, possible.