UNIVERSAL MATTRESS FOR SITTING, LAYING, DECUBITUS PREVENTION AND CURING

Abstract: The mattress and the command unit, according to the invention, are enabling the exchange of supporting area while obtaining, maintaining, reproducing and selfadjusting an optimal operating pressure in the chambers, taking into account the body weight and posture as well as the anthropological measures of the patient. The mattress height is twice or more the chamber width, allowing the better utilization of contact surfaces in depth and on mattress surface which results in lower operating pressure. The mattress enables fitting of contact surfaces to the body shape, and selection of patterns and chamber diameters optimal for undisturbed blood circulation. The mattress is very easy maintainable: it is simple to wash, dries quickly, ventilates spontaneously; it can be ventilated and heated artificially. Its purpose is a comfortable sitting, laying, leaning, decubitus prevention, decubitus healing and preventing of new decubitus wounds appearance. The mattress can be used as a supplement to beds, chairs, wheelchairs, vehicle seats, as a support to lean a head, as an aid bedstead to be used directly on floor or ground. The last is an advantage in circumstances of war or catastrophes. MUTI is significantly cheaper than similar antidecubitus mattresses.

Description: Universal mattress for sitting, laying, decubitus prevention and curing Technical Field The invention relates to the universal mattress with command module, designed for comfortable sitting, laying and leaning. It prevents the decubitus and cures it, ceasing the appearance of the new decubitus wounds in the same time. The invention and the name MUTI are devoted to my mother. She was a patient at a respectful clinic after the hip bone fracture, got the decubitus and ceased in infection. In this sad occasion I have realized that the hospitals and their medical stuff, even at clinical centres, are poorly equipped with the appliances to prevent and, even the less, to cure the bedsore. Permissible pressure magnitude, which is not influencing the blood circulation and therefore not causing the decubitus, according to some published papers, is declared as the mean pressure in the arterial capillaries, about 4 kPa (30 mm Hg = 40.8 g/cm 3 ). Some other authors (K.D. Neander) are taking the mean pressure in venal capillaries, 1.6 kPa (12 mm Hg = 16.5 g/cm J ) as the upper allowable pressure for the region where the body is upheld. However, the measuring made by Khan, K. Lee and their associates indicates that the pressure at the supporting region is increased by 3 till 5 times if any of the prominent bones occurs within the region. The importance of this issue is well known in medicine; the parts of the body lacking fat tissues under the skin are critical in forming the decubitus (fig. 2.7). External pressure, according to the fluid mechanics, should be 3 or 5 times less than 1.6 kPa to allow an undisturbed blood circulation in this critical regions. On contrary to this allowed pressures, the pressures when laying on a hard surface can, at the critical points, reach the magnitude of 40 kPa (300 mm Hg = 408 g/cm 3 ) (fig. 2.7), or even 666 kPa (5000 mm Hg = 6.8 kg/cm 3 ) when sitting (E.R. Tichauer) (fig. 2.3 and 2.4). Using well designed mattresses it is possible to reduce such a high pressures, according to my investigations, to the allowed pressure in the venal capillaries (fig. 2.5 and 2.6). The pressure under 1.6 kPa can be obtained only if the body is completely free of upholding. Healthy person reacts to the inconvenient pressure through a spontaneous or controlled motions. The immovable and often the older persons are not able to move. Seldom (every two hours) complete releasing their bodies from the bedstead is necessary. We can do it turning the diseased person around or using an antidecubitus mattress. Turning the diseased one. some problems occur: • it is difficult to organize the operation if the caretaker stuff is lacking or the nursery equipment is deficient, typically at home • the turning around is painful to the diseased and can jeopardize his health • there are a few areas appropriate for supporting with the adequate pressure and it is difficult to find new upholdings when turning the person • it is impossible to escape the decubitus in every case. There are some problems in the use of antidecubitus mattresses too: • the pressure used is higher than necessary • releasing the body from the bedstead is not complete • the maintenance is difficult (washing, drying, poor ventilation) • there is no mattress to be used therapeutically and in prophylaxis at the same time • mostly, the mattresses are not artificially ventilated, heated, and their fluid capacity (for urine or water) is poor. Generally speaking, there is a lack of functional antidecubitus mattresses. High price is the basic reason for it. In high developed, wealthy countries, the expenses to hospitalize and cure the decubitus are ranging from 20 000 to 30 000 DEM per patient, and it is estimated that 3 - 14% patients get the decubitus ulcers (R.D. Neander). The question is, how to heal poor people in poor countries? It is my ambition, therefore, to take a moderate role in solving the decubitus ulcers problem by MUTI&CO, providing: • hospitals and elderly people refuges should be sufficiently equipped with functional and inexpensive antidecubitus mattresses. In every case of expected decubitus the patient could get, immediately after the reception, an antidecubitus mattress with performances enabling the medical stuff to select the relevant individual parameters for the cure. • lonely, poor and helpless diseased people could use a donated, moderately equipped, but still functional mattress, handled simply and easy (with a tip of the finger) • disabled persons, drivers and the others could have an optimally pressurized seat • the mattress can be used as a bedstead on the floor, in the tent, in all catastrophic circumstances. Background Art The state of technics is obvious. The descriptions of medical and technical problems can be summarized: • numerous antidecubitus mattresses do not ensure the optimal pressure and changes of supporting area; usually, their operating pressures are 2 till 4 times higher than necessary • adequate appliances for curing the decubitus are lacking, particularly those that allow simultaneous decubitus cure and protection • the use of optimally pressurized pillows and mattresses when sitting and laying is not often; the optimal comfort is not achieved • it is difficult to maintain the mattress; artificial ventilation and heating is missing • the prices are to high; numerous potential customers can not afford it. Disclosure of the Invention The operating characteristics / performances are sufficient to describe the possibilities and the aim for universal mattresses, pillows and command units. 1. Purpose and name The mattress and the pillow, according to the invention, are independent functional entities, intended to be used as a protection against decubitus and its healing. They can be used for comfortable sitting, laying and leaning. Mattrasses and pillows can be incorporated in beds, chairs, wheelchairs (fig. 16.4), vehicle seats, used to lean the head, as an aid bedstead (fig. 15.3), straightly on the floor or ground (fig. 15.1 and 15.2). In order to make the mattress that functional and widely useful, I have solved and produced a couple of typical mattresses and command units featuring operating characteristics and fulfilling 28 patent requests that are marking it the primordial one in the domain. Therefore, follows the full name: MATTRESS UNIVERSAL TYPICAL I The abbreviation derivcted from the initials is MUTI. This is the general trademark for a whole range of mattresses and pillows based on the invention. Particular trademarks are: command unit - CO MUTI & command unit - MUTICO MUTI for decubitus prevention - P-MUTI for decubitus therap> - T-MUT1 for prophylaxis and therapy - PT-MUT1 head cushion - H-Ml'TI armchair pillow - AC-MUTI wheelchair pillow - IC-MUTI car seat cushion - C-MUT1 Derived names for particular MUTI types are given in the descriptions. . Optimal operating pressure 2.1. MUTICO operates at the optimal pressure, taking into the account the weight, body position and patient's antropological measures. 2.2. To obtain the optimal pressure, MUTI is made as two rows of strictly dimensioned chambers (fig 1.4 and 1.6). The material is very flexible, sometimes combined with sponge rubber layer (fig. 2.2). Such a solution gains the larger contact area with the mattress. This results with a pressure that is as close as possible to the allowed one - an optimal pressure for the given conditions. 2.3. Operating pressures are proofing that MUTICO, according to the invention, is satisfactory solution. The values of the operating pressures are: less than 6 kPa when a patient sits; less than 4.2 kPa when laying on a single row of chambers and less than 3.33 kPa if both rows of chambers are used (fig. 2.5). This means: if only the arterial capillaries pressure is meritorious for the efficient blood circulation, mattress solution would, according to the invention, satisfy the requsts, yet using a single row of chambers to uphold the body. 3. Changing the support area 3.1. MUTICO enables to change the supporting region from one row of chambers to t o rows and vice versa, from any single row to the both rows. The change can be easily done by CO automatically or semiautomatically, or even manually, by the patient himself or somebody of his family. We should keep in mind that it means the substitution of two medical caretakers. 3.2. The change of supporting region from both rows of chambers (A+B) to a single row (either A or B), as investigated, reduces the contact area from F \ to F (F ), and the pressure therefore increases from P \ to P (Pi). The changes are related: , χ / r , = P 2 χ F 2 = P^Fi- = P n χ F n . where P ] and F \ denote the pressure and contact area for two rows of chambers (A+B), P and F 2 for A row of chambers, 3 and 3 for B row of chambers. Empirically resolved pressure P \ is optimal for the contact area F \ . and therefore, the resulting pressure P 2 Pi) is also optimal for area F 2 (F,). When changing the contact area from F 2 (F%) to F } pressure reproduces itself to the starting value OP \ . It is an obvious advantage of the solution. According to the invention: when changing the supporting region occurs, the pressures are selfadjusting from OP] to OP 2 and reproducing themselves form OP 2 to OP \ , meaning that the operating pressures remain equal to the optimal ones. 3.3. MUTICO enables the timing of supporting region change, ranging from a few minutes to one hour or more. Hence, it is possible to change the supporting region more frequently when the pressures are higher, or vice versa, if the pressures are lower, to slow down the exchange. 3.4. The rate of discharge for a certain row of chambers can be altered from a few seconds to a few minutes. According to the rate of discharge of the chambers, the changes of contact area may be unperceptible, or even stroking changes comparable to a very slow engine action. Although the stroking alteration is more likely the healthy person movements, the invention enables the choice proper to a patient. 4. Contact area distribution Depending on the arrangement of chambers in the upper and lower row in MUTI and it's position in bed, it is possible to: 4.1. exchange the contact area along the single chamber rows with MUTI-R and MUTI-PP, 4.2. change the contact area on a whole surface with MUTI-PD (fig. 10), 4.3. adjust the contact region according to the body contour with MUTI-PD (fig. 1 1 and 12), 4.4. use the parallel or diagonal arrangement of chambers with MUTI-PD, 4.5. position MUTI with chambers parallel to longer or shorter bedside, 4.6. combine variously sized MUTI(es) and sponge rubber pillows to accomodate an individual decubitus therapy or prevention. As recapitulated in paragraphs 4.1. - 4.5, and according to the invention, a wide variety in contact area distribution is possible. The science has to determine optimal arrangement and size of chambers, taking into account the blood circulation parameters, anthropological measures, certain population specifics, etc. Technically speaking: MUTI will answer any request. 5. Decubitus therapy The same MUTI mattress, used for decubitus prevention, can be with some additional equipment (fig. 18) simultaneously used to cure the bedsore (fig. 17). During the therapy, patient uses the complete convenience of MUTICO for decubitus prevention; only difference is the absence of vertical force in vicinity (radiuses 10. 12. 15. 20 cm) of the decubitus ulcer. 6. Choice of materials and parts The choice of parts and materials necessary to produce MUTICO was made particularly carefully. Market availability, large production volumes and series, price/performance, reliable technology, durability, were the basic criterion. This is to guarantee a reliable and long lasting final product. 7 Washing and drying 7 1 MUTI is easily washable (water jet), and dries quickly (in a few minutes) 7 2 Dry cloth is all you need to dry a wet surface 8. Collecting and eliminating the fluid (urine) 8.1. MUTI is designed to accept the fluid (urine, burns liquid, washing water) not keeping it on the surface, to avoid the skin irritation 8.2 Collected fluid can be discharged into the appropriate tank (additional equipment, fig. 19). 9 Ventilation and heating 9.1. Both the shape and the chambers arrangement in MUTI mattress enable spontaneous ventilation above the discharged chambers (fig 20 2) and betw een the chambers (fig 20 3) 9 2 Built in heater and thermostat (fig 21 1) enable the artificial ventilation and heating (fig 20 and 21, airflow 1 and 2) 9.3. The air blowing when the chambers are discharged (fig 20. and 21 , air flow 3) can be used to ventilate MUTI. 10 Combining mattresses and pillows 10 1. Esthetically designed seat furnish (fig 16.2) can be obtained combining mattresses and pillows consisting of chambers w ith a layer of sponge rubbei Seat with lest (fig 16 5) and bedstead (fig 15 1 ) ate leahzed in the same way The examples are featuring all performances present in MUTI-PP / MUTI-PD 10.2 Mattress with single row of chambeis (fig. 13 1) can be converted to a double row seat with single row rest (fig 13 2) 10 3 Mattress with single chambers row can be used as a seat and rest (fig 13.3) 11. Head cushion MUTI made of single chambeis row with the sponge (fig 14 3), MUTI-PP and MUTI-PD (fig 14 4) with or without sponge, can be used as a single functional entity to uphold the head If the support with changeable elevation is added below the cushion (fig 14 1 and 14 2), it can be used, m the same time, to change the inclination of the head 12. Command unit 12.1. The command unit enables changing of contact regions, simultaneously keeping, selfadjusting and reproducing the optimal pressure. 12.2. According to the invention, and to fulfill the operating characteristic 12.1 , various command units and air sources are available, all of them featuring similar functionality, but priced in range from 30 till more than 300 US$. The intention was to approach every market potential. The cheapest, manual command unit, involving more attention and care, obtains the results similar to those given by the most expensive programmable automatic command unit. 12.3. The air may not leave a row of chambers before the optimal pressure is obtained in one or both rows of chambers. 12.4. The usage of compressed air to change the supporting region form two rows of chambers to one row and vice versa is 20 till 50% of total air capacity. 12.5. There is no danger in handling the command unit, as the operating media is low pressured air (less than 100 g/cm 2 ). Operating characteristics 1 - 12 result in: solution to supporting area exchange, frequency of changes, chamber discharge rate and optimal pressure in chambers. At will, those operating characteristics enable the movement simulation (for immovable patients). Such benefits may be pleasant and utile even to the healthy persons. As there are the other advantages, like easy washing and drying, ventilation, heating etc., all the requests for successful decubitus prevention and cure are fulfilled, and it is the basic objective of the invention. Operating Characteristics Description Optimal pressure MUTI operates at optimal pressure, avoiding unnecessary and uncontrolled high pressures at upholding zones. Optimal pressures are obtainable on the appropriate area sizes, according to P x F = G, P denoting the pressure (g/cm " ), F the contact area size (cm 2 ) and G the patient's weight (g). (The choice of measuring units is appropriate to the invention description, and will remain in use.) Increasing the contact area is achieved if the body is immersed deeper in the mattress, enabled by the height of mattress, low chamber pressure and flexibility of mattress walls. Enlarging the mattress height is limited and justified to a certain measure, therefore we can speak about the optimal mattress height. The optimal mattress height is the one making possible a high rate of contact area use, without the loss in comfort or upholding stability. According to the invention, 80 mm is taken as the optimal mattress height for it's general use. Lower mattress (less than 50 mm) has to have higher pressures within the chambers, particularly for sitting, to avoid the contact of exposed parts of the body to the hard base (compare fig. 1.1 and 1.3). Mattresses higher than 100 mm incline to be unstable and uncomfortable, and the increase of contact area is not significant. What more, large chamber diameter (50 cm) leads to decrease of contact area use in it's width, that means, at the edges of the body (compare fig. 1.2, W 2 and fig. 1.5, W 5 ; where W 2 is smaller than W 5 ). The contradiction is solved, according to the invention, designing the mattress in two rows of smaller diameter (R, fig. 1.4) chambers. In this way, mattress height is twice the single chamber width; therefore, the uphold width is increased from W 2 to W 4 (fig. 1.4). The optimal mattress height can be realized combining single row of chambers, R in diameter, with a sponge rubber layer of a certain height. At the sponge layer occurs the first distribution of body weight, producing the pressure. Another (re)distribution of pressures (body weight) is indirect, transiting from the sponge layer to the row of chambers (fig. 2.2). Finally, the pressure is distributed over the whole contact area, being higher above the inflated chambers, varying and lower above the deflated ones, depending upon the chamber diameter, the pressure in inflated chambers, sponge thickness, etc. Mattress made of chambers completed with the sponge layer is successfully solved if the contact area pressure, above the deflated chambers, is lower than the pressure in venolas. The optimal pressure, being the basic characteristic of the invention, is achieved, kept, reproduced and selfregulated through the solutions of chambers, choice of materials, and MUTI&CO design. Effect of pressuring duration to the occurrence of decubitus Not only the extent of the pressure, but also it's duration is to be taken into account: • turning the patient around is necessary • published works reveal that the product of the time interval (hours or minutes) of supporting place exchange and the pressure in this place should remain constant. From the viewpoint of the invention, the existence of some correlation between pressure extent, it's duration and the occurrence of decubitus is acceptable, being it constant product (pressure times interval) or some other one. What is necessary for sure: • match the frequency of uphold place exchange with the needs of the user • use the optimal pressure at the uphold place. The requests are realized with MUTI&CO as follows: • the user is laid on mattress. Both rows of chambers are inflated until the mattress detaches the body from the hard base. Measured pressure value, enlarged for approximately 10%. corresponds to the optimal operating pressure (ORP ) for a certain user; it is then adjusted by a reductor valve. • as the time to exchange the uphold region comes, one row of chambers is discharged, while the another remains inflated. Body weight is translocated from two rows of chambers to one row, and the pressure within it increases through the selfadjusting • the next cycle of exchange consists of inflating the deflated row of chambers until the initially defined optimal operating pressure ORP] is not reached in both rows. The body weight is again distributed to the both rows of chambers. During the exchange of supporting area, according to my research, some facts were observed: • the utilization of the compressed air is at least 50%, as the air is partly reused • if the optimal operating pressure when both rows of chambers are used is about 3.3 kPa (34 g/cm 2 ), then the pressure when laying on a single row increases to about 4,2 kPa (43 g/cm 2 ), or approximately 35%, not for 100% as it should be expected theoretically • the optimal operating pressures within MUTI, according to the invention, when laying on a single row of chambers, and particularly on two series, are under the upper pressure level specific for arterial capillaries • upholding pressure on a single row of chambers is lower if the initial pressure, on both rows, was lower. Exchange of contact areas The exchange of contact areas at MUTI-PP happen along the particular rows of chambers: when row A is inflated (fig. 9.1 ). or row B (fig. 9.3), or when both A and B rows are inflated (fig. 9.2) The contact area at MUTI-PD, as conditions in chambers are changed, alters in all the three dimensions (fig. 1 1). The outcome of the changes are variable heights along the mattress as it is loaded. The description illustrate three drawings showing MUTI crosssections (fig. 10, 1 1 and 12). when particular (A or B) or both rows of chambers are inflated. Example 1 If only a single row of chambers is inflated, A (fig. 10.1 ), or B (fig. 10.3), then: • under the area marked PDP there are three inflated chambers, situated parallel - diagonal - parallel • under the area marked PD there are chambers situated parallel and diagonal • under the area marked PP there are two parallel situated chambers • under the area marked D there is a single diagonally positioned chamber • under the area marked P there is a single chamber positioned in parallel • under the area marked 0 there are no inflated chambers. Example 2 The same symbols are used to illustrate relative positions and a number of chambers when both series of chambers are inflated (fig. 10.2). As shown, the central area is filled with parallel and diagonally positioned chambers PD, and the edges of the pillow are two fields filled with PP and PDP chambers (instead of PP and PDP chambers it is possible to fill MUTI edges with PD chambers or a sponge rubber layer). If a rubber cloth is set between the upper and lower rows of chambers, and only one series of chambers is inflated (fig. 1 1.1 ), the gaps between the inflated chambers in lower row are bridged. Than the upper row chambers, carrying the body, can not fill the space between the chambers in lower row, particularly in the middle of the pillow, as it occures when the cloth is missing, and the load from the upper row of chambers is transferred to the cloth, further to the chambers in the lower row (comp. fig. 1 1.1 and 11.2). The resulting height of the mattress in the places where the cloth is tightened approximately equals to the double row mattress height, independently which series of chambers is inflated. The cloth between the chamber rows can be tightened arbitrary. If it is looser, the upper row chambers can drop deeper between the lower row chambers; in this manner the mattress height can be lowered from 2R to R, particularih in its middle. Tightening the cloth the cloth can raise from R to 2R. Changing the height of a mattress w ith PD distributed chambers can be done using a cloth of a certain width that is moved betw een the chambers along the pillow (fig. 12). For instance, moving the cloth from the position I to II. respectively to III, the area of PD chambers if enlarged versus the P and D chambers area. Decubitus therapy apparatus The basic proposition for a successful decubitus therapy is to avoid vertical and horizontal forces (F. g/cm " ) affecting the place where a decubital wound has appeared. It is possible to eliminate the vertical forces completeK if the part of the body where sore occurred is separated form the mattress (fig. 17). The horizontal forces are more difficult to eliminate. However, the effect of these forces can be reduced if the free space around the wound is enlarged and if in the encircling space the pressures affecting the healthy tissue is as low as possible. The height of MUTI (/;) under the decubitus wound is lowered by the contraction of chambers using the two disks of an appropriate diameter (fig. 18.1 and 18.2). The disks fixing elements (fig. 18.3 and 18.4) provide a gap between the disks necessary for undisturbed air flow. The disks can be positioned anywhere on the mattress, making the openings in the rubber cloth. One disk is positioned under the rubber cloth, the another above the mattress chambers, both tightened by the fixing elements. MUTI-PD is optimal for decubitus therapy, and the most appropriate area is the middle of the mattress. Collecting liquids If a patient urinates out of the control, or if a liquid is splashed, MUTI can hold a certain amount of the liquid (fig. 19). MUTI itself is a repository if front sides with chamber collectors are closed, while the bottom and the lateral sides are rubber cloth. If, in addition, the central part of the MUTI bottom (fig. 19.3) is equipped with an porous tampon (fig. 19.1) which drenches and capillary drains the liquid to an urine bag (fig. 19.4), MUTI in the case necessity can be used as an container for liquid. The urine or washing liquid can be drained through the collector openings as well (fig. 19.2). Spontaneous ventilation The pillow enables spontaneous flow of the air: • above the deflated chambers (fig. 20.2), • between the chambers (fig. 20.3). Artificial ventilation When changing the support place from two to one series of chambers, a certain quantity of the air goes out. The quantity can be directed between the MUTI chambers, and further to the certain support region (fig. 20 and 21 , air flow 3). The air can be conducted directly from the air source into the certain MUTI gap (fig. 20 and 21, air flow 2) to ventilate MUTI. If the heater is used (fig. 21.1 ), the hot air can be blown into the chambers (fig. 20, air flow 1 ), and left out into MUTI gaps (air flow 3). Depending on input air temperature and frequency of leaning region interchange, it is possible to affect the air temperature within MUTI. The hot air can be redirected by the valve (fig. 21.2) and directly injected between the chambers (fig. 20.1 , air flow 2), so heating the MUTI space at a convenience. Short description of the figures Fig 11-16 Effect of chambers diameter to contact area size Fig 21-27 Actual pressures in MUTI compared to the pressures on a hard bedrock Fig 31-311 MUTI elements, t pes of collectors, chambers profiles Fig 41-47 Distribution of the compressed air to MUTI, within MUTI and valve intersections Fig 5 MUTI-R - single row of chambers Fig 6 MUTI-PP - parallel/parallel chambers arrangement Fig 7 MUTI-PD- single tube, parallel/diagonal chambers arrangement Fig 8 MUTI-PD - two tubes, parallel/diagonal chambers arrangement Fig 9 Contact surfaces interchange - MUTI-PP Fig 10 Contact surfaces interchange - MUTI-PD Fig 111-113 Arrangement of single inflated series of chambers at a three intersections on MUTI-PD, with and ithout the cloth between the lows of chambeis Fig 12 Contact surfaces interchange - M TI-PD with a moveable cloth between the lows of chambers Fig 131-134 MUTI-R applied to the seat with and without the rest, with and without the sponge rubber Fig 141-144 MUTI head cushion ith a support to lean the head Fig 151-153 MUTI as bed mattress aid bedstead on the floor, with and without the sponge rubber Fig 161-165 MUTI utilization examples wheelchair, head support, seat, rest Fig 17 MUTI for decubitus theιap\ Fig 181-184 Decubitus therap\ apparatus Fig 191 - 194 Collecting and draining of liquids Fig 201 - 203 Spontaneous MUTI \entιlatιon and \entιlatιon b> the an exhausting fiom the chambeis Fig 211-214 Heating device, and the distribution of hot oi cold air within MUTI Fig 221 - 2210 MUTI operation using automatic, semiautomatic and manual command unit, and possible sources of compressed air Fiϋ 231 - 238 Semiautomatic command unit with the air souice The Way to Realize MUTI MUTI is designed according to the directives revealed from the operating characteristics description. MUTI consists of the chambers made from a rubber tube of certain diameter. Rubber was chosen to make the mattress because of the following characteristics: • rubber tubes technology is well known and established, • chamber walls made of the apropriate type of rubber fit a body shape properly, • increased pressures due to crease in fabric of bedcover or underwear are less asserted in the contact place, as the crease partly drives in the elastic rubber enclosure, • the mattress made of rubber tubes is easy washable, drains and dries quickly, rapidly ready for reuse, • the rubber is resistant to a friction and usual mechanical loadings, • a thin rubber wall easily withstands even five times higher pressures, without a permanent deformation, than those anticipated by the invention. If occures an invention of any other synthetic material, featuring better characteristics than the rubber and better price, the production of the cushion can be easily redirected to use it. The chambers can be stacked: • in a single row, MUTI-R (fig. 5), • in two rows, MUTI-2R (fig. 6). Possible arrangements of two ro MUTI chambers are: • parallel distribution in both rows, MUTI-PP (fig. 6) • parallel distribution ir. one row and inclined (diagonal) distribution of chambers in the another row, MUTI-PD (fig. 7 and 8). MUTI-PD is made of: • a single tube of a ceπain length if it is used for leaning without the change of the supporting area (fig. " ). • two tubes of a certain length if it is to enable the change of the supporting area (fig. 8). The alternating chambers of a single chambers mattress (MUTI-R or MUTI-PP). are connected to the air splitter (fig. 3. ' .) into the two series of chambers A and B (fig. 4.1). If MUTI is used as a autonomous entity, its air valves are located at one end, and if more MUTIes are use for a single bedstead, two more valves are added to the another end of the collector (fig. 4.2). The valves are designec to open when the air couple is inserted into the valve hole (fig. 4.5). When the couple is pulled out (fig. 4.7), the valve closes air flow (fig. 4.6). Such a vah e enables MUTI to be used for changing the support place or as an autonomous sitting unit. Additional safety plugs are intended to the mattress MUTI used just for leaning (fig. 4.4). Chamber ends of a mattress are inserted into the chamber collector (fig. 3.2). The chamber collectors are enabling: • fixing the chamber ends, • more compact mattress, • esthetic appearance, • more comfortable leaning at the mattress ends. As a chamber collector can be used: • a rubber tube piece of a appropriate diameter, hermetically closed by a valve, which is bent and affixed to the ends of mattress chambers (fig. 3.7). Such a collectors are easy to make, can be inflated to a desired pressure, they are simpler and cheaper. • pressed or injected rubber collector (fig. 3.5) • polyurethane, rubber sponge or something similar (fig. 3.6) • rubber cloth that is used for MUTI bottom is bent around the chamber ends; between the chamber knee and the cloth a soft pad is inserted for a more comfortable leaning. The collector chamber width, denoted MUTI (S). depends on the number of chambers (n) and chamber diameter (R): S = R x n . Suppose that following palette of collectors and respectfully widths and heights of MUTI can satisfy the market demands: Using the collectors dimensioned as above it is possible to make mattresses of different sizes and for different purposes. Usual mattress lengths are: • bedstead up to 2000 mm, • seat up to 500 mm, • rest up to 650 mm, • head cushion up to 900 mm. The chambers are affixed (in the inflated state) to the rubber cloth (fig. 5.1). In this way MUTI bottom is protected against the mechanical damages, a desired distribution is obtained and the chambers are fixed, defining operation area of certain chambers. For the upper mattress side, exposed in utilization, just bedcover is used. Convenient material is a stretchable one, enabling the enlargement of contact area and good ventilation through the pores within the cloth. MUTI can be inserted into the cushion cover as well. MATTRESS TYPES DESCRJPTION Single row mattress, MUTI-R MUTI-R consists of a series of chambers (n) placed in a single row with diameter R (fig. 5). Based on the single row mattresses (fig. 13.1) the following typical cushions are developed: • the integral single row mattress used as a seat and a rest (fig. 13.3). At a transition line from the seat to the rest an appropriate band is fixed to obtain a desired bending angle. MUTI can have integral covering for both seat and rest. The pillow can be inserted into the separate pillowslip and tied to the seat by the band. • the integral single row mattress used to form single row rest and a double row of chambers seat (fig. 13.2) • MUTI combining chambers and a sponge layer (fig. 13.4), a single row mattress with a sponge layer above it. put together into a pillowcase or used with just a bed linen above the sponge. As the sponge can be formed by appliances, those cushions are adequate where the esthetic is as important as the functionality. Double rows mattresses, parallel arrangement - MUTI-PP MUTI-PP chambers (fig. b) are made of rubber tubes (diameter R. length L) vulcanized to form a closed ring, like a bicycle tire: than it is stretched (fig. 3.4) to obtain a single chamber of the two tubes positioned one above the another. Alternating chambers of MUTI-PP are connected by an appropriate air splitter (fig. 3.1 ). A rubber cloth is used for the bottom of the pillow. Between the rows of chambers a strong cloth can be inserted or the chambers belonging to one row are glued to the appropriate chambei s in the another row. Mattresses with parallel and diagonal arrangement - MUTI-PD The production of mattresses using a single chambers MUTI-R and MUTI-PP takes more hand labor, making the product more expensive. Therefore is planned, according to the invention, the production of mattresses using a single undivided rubber tube (fig. 7) or two undivided tubes in two rows in such a way that resulting mattress has a row of parallel and a row of diagonal chambers. Internal arrangement of the parallel and associated diagonal chambers recalls an orthogonal triangle. If the mattress is made of two tubes, the longer triangle side (a) equals in length to the parallel placed chamber, the shorter triangle side (b) equals the double chamber diameter (b = 2R) and meets the step of winding the tube, while the length of the diagonal chamber (c) equals c 1 = a 2 + (2R) 2 . If the mattress is made of a single tube, the shorter triangle side (b) equals the chamber diameter R and meets the step of winding the tube, and the length of hypotenuse (c) equals the diagonal, c 2 = a 2 + R ~ . As the hypotenuse equals or just slightly differs from the diagonal, this chambers arrangement is called parallel/diagonal (PD). The advantages of mattresses with the parallel/diagonal arrangement compared to the parallel/parallel one are: • it is easier to manufacture them in series • the interchange of contact surfaces is enabled along and across MUTI, and the change of height is possible at various MUTI intersections • by positioning and tightening the cloth of a certain width between the rows of chambers MUTI height can be changed from R to 2R, to trim the mattress to a body shape. Making a MUTI-PD starts with winding of two rubber tubes, or a single rubber tube, from one MUTI corner to the opposite MUTI corner according to a certain arrangement and with a leap equal 2R or R, around two axes spaced mutually for a pillow length. On the lateral sides of the pillow, for technological and functional reasons, along the diagonal positioned chambers, there are two parallel fixed chambers or a sponge layer of an appropriate diameter. This gives more height to the lateral mattress ends, preventing a patient to fall from the bed. Some of the standard chamber collectors are affixed to the frontal sides of the mattress. At one end of the rubber tube, or on both ends if needed, the air valve is installed. The bottom of the mattress is provided with a rubber fabric. The cloth between the rows of chambers can be installed in a different ways: « gluing it across the entire surface • using a movable cloth of a certain width, tightening it as required • inserting a cloth of a certain width between the chamber rows, twisting it around a row of chambers and (detachable) connecting the cloth ends to the bottom of the pillow. • gluing upper and lower chambers, belonging to the same series, at a chamber contact. Command unit A few kinds of command units are designed for MUTI: 1. entirely manual (fig. 22.1) and partly manual (fig. 22, pos. 22.7 and pos. 22.9), 2. semiautomatic (fig. 22.2 and 23), 3. automatic (fig. 22.3). 1 . Manual command unit 1.1. manual CO, consisting of a pump driven by a hand (fig. 22.6) or by a leg (fig. 22.5). a backflow valve and a pressure reducing valve (fig. 22.4). 1.2. partly manual CO. consisting of an electromagnetic (membrane) pump (fig. 22.7), backflow valve (22.1 1), a pressure reducing valve (fig. 22.4) and a manual control device (fig. 22.9). 2. Semiautomatic command unit. PCO PCO consists of: 2.1. compressed air source 2.2. command unit 2.1. Compressed air source The compressed air source for semiautomatic and automatic command unit operation and inflation of MUTI can be: 2.1.1. miniature compressor plant, 2.1.2. central compressor plant with a pneumatic installation. 2.1.1. Miniature compressor plant consists of: • An electromagnetic pump (fig. 23.1) with a rheostat controlled air flow and operating pressure. • A backflow valve (fig. 23.2) installed behind the pump, to prevent the release of the air from the system: this avoids decreasing the pressure of the chambers and therefore frequent switching the pump on and off. The backflow valve has to operate reliably at the low pressures typical for the system (20 kPa or less). • A reservoir (fig. 23.3 • of a certain capacity to secure, together with the backflow vah e. a smooth and reliabK system operation. • A micro switch ( fig. 23.4) to operate the pump automatically. The micro switch operates properly using a big difference in pressures within the reservoir and MUTI: in this way the system maintains reliably inflated to the desired pressure before the pump disengages itself. The micro switch has a knob to adjust the operating pressure within the reservoir. The air compressor plant designed according to the invention is autonomous, and once switched on continues the operation automatically. Miniature compressor plant is a complete product according to the invention. 2.1.2. Central compressor plant Functional, proper and reliable compressed air supplying of numerous MUTIes can be accomplished with a compressor plant featuring higher capacity and higher operating pressure. Installing the compressor plant and a pneumatic installation is justified in hospitals, elderly people lodges, or any place else where a number of users justifies it in terms of technology and economy. The compressor plant has to be placed into the separate, acoustically isolated room. The pneumatic equipment has the reduction valve and air outlet by each bed. To use MUTI, it is enough to plug its control unit into the air outlet. 2.2. Command unit Consists of: • A reduction valve (fig. 23.5) that provides reliable reaching and reproducing of the desired pressure within MUTI. The pressure can be red at the reduction valve scale. • A manometer (fig. 23.6) for observing the pressure within the chambers and the changes in them. It is a sensitive instrument, rather expensive, but as a replacement for eventual pressure controls, an ordinary blood-pressure meter can be used, or the pressure is red from the reduction valve. « A control unit (fig. 23.7 and 22.9) which is a manually operated valve 5/2 adapted for use with MUTI. There are three operating positions: zero (middle) position - the both series of chambers are inflated, and two extreme positions - a single series of chambers is inflated (A or B). • A throttle valve (fig. 23.8) to adjust the rate of deflating. If in the throttle valve hole, where the air exhausts, a small pipe is inserted and immersed into the glass of water, than it is possible to observe the speed of the air exhausting the chambers. The hole can be used to connect a blood-pressure meter to control the pressure within the chambers. 3. Automatic command unit The automatic command unit consists of: 3.1. compressed air source 3.2. appropriate switches 3.3. two electromagnetic valves 3/2 3.4. time relays 3.5. manometer 3.6. reduction valve 3.7. throttle The air source, manometer, reduction valve and throttle are identical to those used in semiautomatic device. The switches and manometer operate based on changes of pressure in the reservoir and a particular series of chambers. The time relays are used to set the time intervals when inflation and/or deflation of particular series of chambers are to occur. Use of the command unit According to the invention, any of the referred command units and compressed air sources can be used to accomplish any task. At the automatic device, recommended for immovable patients, it is advisable to preprogram the desired pressure, time intervals to perform a supporting place interchange and times to inflate and deflate the chambers. At the semiautomatic de\ ice equipped w ith its own air source it is necessary to switch the valve to one of the three available positions in a certain time intervals, depending on the inflation or deflation desired to perform. The chambers pressure value, rates of inflation and deflation and the pump operating pressure are preset. If there is no automatic or semiautomatic CO, the operations like supporting area interchange or pressurizing are accomplished using a manual device or the mini pump and a blood-pressure meter. To inflate MUTI w ith manual CO the air couple is inserted into the valve hole of series of chambers to inflate (A or B. or A+B, fig. 22.10). After the desired pressure is reached, the couple is pulled out (fig. 4.7) and replaced with a safety plug (fig. 4.4). If a series of chambers is to be deflated, the couple (disconnected from the pump) is inserted into the appropriate valve hole. If a partly manual device is used, there is no need to insert and pull out the couples from valves when a change in the chambers takes place. If MUTI is used just for sitting or laying, and there is no need to change the supporting area, the chambers are inflated to the pressure as adjusted on pressure regulator, or till the user himself feels the pressure that suns him at most, or till he is separated from the hard bedrock. As desired pressure is reached, the pump and pressure regulator are taken of MUTI and valve hole is closed with a safety plug. The pressure regulator is sufficient to reach and reproduce the desired pressure at any time.

Claims: CLAIMS 1. Universal mattress and pillow for sitting, laying, decubitus prevention and decubitus therapy, formed of air-filled chambers (in following text referred as mattress or pillow an command unit), characterized by the chambers consisting of two (or more) smaller diameter tubes, made of material that fits the body shape; the tubes are positioned one above the another (isobaric); therefore the mattress has at least the double height compared to the chamber area width; this gains a larger contact surface in the pillow depth and better use of its surface (comp. 1.3. and 1.4), which are the basic propositions to achieve the optimal operating pressure - the lowest operating obtainable pressure in a reliable designed air mattress. 2. The mattress is, according to the Claim 1, characterized by the chambers being connected to two series which are alternatively inflated and deflated; the interchange of contact surfaces happens from two series to a single series and vice versa; an optimal pressure for a certain user establishes itself when the patient is laying on two series of chambers; during the interchange of supporting region from two to a single series the pressure is selfadjusted to a new amplitude being again optimal, under the new circumstances; originally established pressure is selfreproduced as the change of supporting region takes place from one to two series of chambers; this means that the pressure at contact of mattress and body is always optimal, according to the invention. 3. The mattress is, according to the Claim 1 , characterized by two basic types: the first has parallel to parallel distribution of tubes, where a tube in one row is placed parallel to a tubes in the other row (6), and the interchange of contact surfaces happens along the chambers of particular series (9), while the second basic type has one row of tubes parallel to one of mattress side, and one row of tubes placed diagonally to the tubes in the first row (7 and 8), and the interchange of contact surfaces happens simultaneously along the parallel and diagonally positioned mattress chambers. 4. The mattress with parallel / diagonal chambers is, according to Claims 1 and 3, characterized by the number of tubes used for its assembling: a single entire tube if the mattress is used just for supporting (7), or two (or more) entire tubes if it is intended to enable the interchange of supporting region (8); the mattress height can be affected by inserting a cloth between the rows of tubes (1 1.1); the cloth can be moved along the mattress and tensioned in a different ways (12); both sides, one with parallel chambers or the other with diagonal distribution of chambers, can be used for leaning; the mattress can be inserted with chambers oriented along or across the bed - this enables to adapt the mattress contact surface to a body shape and based on blood circulation and anthropological measures use the optimal distribution and diameter of chambers to a certain population of users, according to the invention. 5. The mattress is, according to the Claim 1, characterized by a simple maintenance: it can be easily washed, just with the jet of water: dries quickly - it is ready to reuse in a few minutes; wet surfaces are easy to dry with a cloth; its design enables receiving of liquids as the patient is washed, as he urinates or in other occasions; the collected liquid can be, using the additional equipment ( 19), gravitationally dispatched to a sewer. 6. The mattress is, according to the Claim 1 , characterized by the shape and distribution of chambers which enable a spontaneous ventilation (20) and the additional equipment enables the artificial ventilation and heating ( 1). 7. The mattress with the command unit is, according to Claims 1 and 2, characterized by the ability to change the supporting region in arbitrary' defined time intervals, changeable rate of chamber deflating, changeable rate of inflating, incorporation of vibrator, enabling the choice of the parameters that suit the user at most. 8. The mattress, according to Claims 1 - 7, is characterized by providing an optimal operating pressure, which is sufficient for comfortable support, then the change of the supporting place, the accommodation of mattress contact surfaces to a body shape, easy washing and drying of contact surfaces, ventilation, heating, etc.. fulfilling all the conditions for successful decubitus prevention, and it is the main goal of the invention. 9. The mattress for decubitus prevention, according to Claims 1 - 6, is characterized by its possible utilization in curing an already existing decubitus (17); a device for eliminating vertical forces affecting the decubital wound is installed under it (18). the diameter is adjusted, and the patient can use all the conveniences of the antidecubitus mattress elsewhere, preventing the occurrence of any new decubital wounds, according to the invention. 10. The mattress, according to the Claim 1, is characterized by possible combining of chambers with a sponge rubber layer: the interchange of contact areas is identical, but not smoother compared to the type of mattress that is under the sponge rubber; the another advantages are that in case of uncontrolled deflation of chambers the body is not leaned to a hard bedrock, the sponge can be formed to fit the mattress of chambers into the furniture, and what more, the sponge can be used as an addition to the mattress of chambers in the domains where the pressures are not critical, while a high layer of sponge at the lateral bedsides can protect the patient from falling out of the bed. 1 1. The mattress, according to the Claim 1 , is characterized by the control air valve (4.4) designed to improve its functioning: the valve is opened for air in both directions if the couple (4.7) is inserted into the valve hole (4.5). as it is used to change a supporting place, and it is closed for the air when the couple is pulled out from the valve (4.6), adding the safety plug as the mattress is usec for leaning. 12. The mattress, according to the Claim 1 , is characterized by its possible use as a head cushion with certain optimal inner pressure (14.3, 14.4), and the additional support under it (14.2) to change the inclination. 13. The command unit is semiautomatic, portable, consisting of air source, pressure regulator and controls, according to the Claim 1 , characterized by controlling the interchange of the supporting area from two series of chambers to a single and vice versa, obtaining, keeping and reproducing the optimal pressure, adjusting the rate of chambers inflation and deflation, automatic air pump control, centralized handling, remote action covering all the functions similar to TV remote controller, internal pressure reading in a few ways. 14. The automatic command unit, according to the Claim 1 , is characterized by controlling, automatic and programmable, the interchange of supporting area and reproduction of optimal pressure. 15. The command unit, according to the Claim 1, is characterized by the air source - a mini air pump, powered by hand, foot or by electricity; the regulation valve is used to establish, reproduce and read the pressure, while the control unit is used to change the supporting region. 16. The command unit, according to the Claim 1. is characterized by the air source - a mini air pump, powered by hand, foot or by electricity; the regulation valve is used to establish and reproduce the pressure, while the supporting region is changed my manual inserting and pulling out the air couple into the appropriate valve of the mattress. 17. The command unit, according to the Claim 1 , is characterized by the two basic components to replace any command unit missing: a little pump and a manometer are sufficient to obtain the optimal pressure and perform the supporting area interchange. 18. The command unit, according to the Claim 1. is characterized by the efficient use of central compressor plant if there is a number of patients in a place; the pneumatic installation is settled, with the reduction valves by each bed; control unit is then pluged in a certain bed outlet only when necessary to carry out some operation. 19. The command unit, according to the Claim 1. is characterized by the compressed air consumption: the air from a series of chambers is not let out before the optimal pressure is achieved in the another series of chambers, therefore the air consumption is 20 till 50%) compared to the theoretically expected amount; handling the control unit is not dangerous, as the working media is low pressure air (less than 10 kPa).

Inventors: MARICEVIC ZDRAVKO, MARI&CCARON
Applicants: MARICEVIC ZDRAVKO, MARI&CCARON
Application year: 1999
Main classification: A47C27
IPC codes: A47C27, A61G7