US3394415A - Pressure pad with independent cells - Google Patents

Description

yJuly 30, 1968 B.A. PARKER l PRESSURE PAD WITH INDEPENDENT CELLS Filed April 6.

2 Sheets-Sheet l Buster A. Parker INVENTOR W 5 Anm-.nefs

July 30, 1968 x a. A. PARKER 3,394,415

PRESSURE PAD WITH INDEPENDENT CELLS Filed April 6, 1966 2 Sheets-Sheet 2 Buster A. Par/rer I N VEN TO R United States Patent O 3,394,415 PRESSURE PAD Vl/HTH NDEPENDENT CELLS Buster A. Parker, 8612 Sierra Uval,

Parma, Ohio 44130 Filed' Apr. 6, 1966, Ser. No. 540,669 7 Claims. (Cl. 5-34S) ABSTRACT F THE DlSCLOSURE An alternating pressure pad for bedfast patients defined by a plurality of independent side-by-side cells or tubes which are alternately inflated and deflated and arranged in interdigitated sets. A strap assembly retains the cells in side-by-side relation without forming a bridging support across the top of the cells and a heel supporting tube is provided across the upper surface of the pad. The dimensional characteristics of the cells and the mechanical associational relationship thereof is such that they will prevent a patient from bottoming against an underlying mattress in the area between the inflated cells with the cell surface conforming to the patients body contour thus given even support by enabling a lower pressure to be employed.

The present invention generally relates to an air mattress or pad for use under bedfast patients by which the pressure points where the patients body engages a mattress are eliminated thereby eliminating bedsores due to such pressure points, and materially increasing the comfort and well being of the patient.

It is well known that pressure sores or bedsores occur on bedfast patients. These sores occur ybecause weight of the patient collapses the blood vessels between the patients lbony protuberances or prominences and the mattress thus preventing adequate blood flow thus starving the tissue. Many efforts have been made to alleviate this problem. For example, a common practice is to turn the patient but from a practical standpoint, this is substantially physically and economically impossible insofar as providing satisfactory relief is concerned. Various topical applications such as ointments, solutions and the like have been provided for the treatment of pressure sores but while they Vassist in healing, they in no way correct the cause, that is, the pressure which prevents blood circulation.

The present invention relates to an improved device which has been found most satisfactory to correct the cause of the problem and includes an alternating pressure pad. Such pads presently are composed of two sets of air cells together with an air compressor or pump with suitable pressure controls and operating mechanism for alternating inflating and deilating the sets of coils so that pressure is removed from the body in the area between the inflated cells. While such pads are very helpful, certain limitations and deficiencies exist in presently available alternating pressure pads.

Accordingly, it is an object of the present invention to provide an alternating pressure pad which includes alternately inflated and deflated cells in which the individual cells are completely independent and separate from each other with the independent cells being mechanically retained generally in side-by-side relation to provide a pad covering substantially the complete area of a bed.

From an inspection of the previously known products such as 4illustrated in Rand Patent No. 2,719,986, issued Oct. 11, 1955 and Grant No. 3,199,124, issued Aug. 1965, it will be noted that currently available pads basically include two sheets of polyvinyl chloride plastic film sealed together to form the proper channels or cells into which the air is pumped. In these devices, the cells are approximately 2" wide when collapsed and approximately 3,394,1ll5 Patented July 30, 1968 1% in diameter when inflated. In the Grant Patent 3,199,124, the heel cells at the foot end of the pad are reduced to approximately one half the standard diameter since it is well known that the heels are unusually susceptible to pressure sores and special care must be given to them.

One manufacturer in this field asserts that a heel of a patient will bridge between two cells that are about .637 in diameter when the intervening cell is deflated. Noting that the seal between the cells is .125 wide and that this seal holds the heel cells apart as well as in a flattened rather than true cylindrical shape, it will be recognized that the heels of most patients receive very little benefit from the heel cells. It is also noted that the standard diameter of 11A of the cells are also spaced apart .125. It has been found that in order to support or float a patient on the alternately inflated cells, an air pressure of 8O to 100 mm. of mercury must be employed. If less pressure is employed, the bony protuberances or prominences such as the shoulder blades or the coccyx will bottom on the mattress between the inflated cells or because the cell is only 11A in diameter, these protrusions may push an inflated cell flat as well as the adjoining uninflated area. Higher pressures in this diameter cell are sometimes used for correcting this problem but the cells then become unbearably hard.

Another essential arrangement is the orientation of the air cells longitudinally of the patient since transverse cells have been found to dam the venous return. Also, as the cells inflate, they reduce the measurement of the pad perpendicular to the cell extension while the integral manifold feeding the cells resists this reduction thus causing pad distortion. This distortion or humping of the pad is often disturbing and uncomfortable to the patients.

Also, inasmuch as these pads are constructed of a vinyl material containing volatile plasticizers, they will become brittle and otherwise deteriorate thus causing failure due to a leakage. While pinholes can be patched, the commonly occurring seam splits cannot be and it is impractical but necessary to return the mattress to the manufacturer to have repairs made.

In view of the limitations and deficiencies in presently available equipment as outlined above, it is a primary object of the present invention to provide an alternating pressure relieving pad which involves the use of completely independent cells which are disposed in side-byside relation and communicated with a pair of manifolds at one end thereof which are communicated with a source of alternating inflating pressure and deflation of one set of cells in which the independent cells are free of each other substantially throughout their length and which are constructed with a diameter sufllcient to enable less pressure to be employed for cradling and receiving the prominences of the patients body for supportingly engaging more of the surface area thereof and preventing bottoming of the bony prominence against the underlying hospital bed mattress.

A further object of the present invention is to provide an alternating pressure pad constructed of separate air tubes held together by strap arrangements so that in the event one of the tubes or cells is punctured, it only requires that this one cell or tube be easily replaced without necessitating the return of the pad to the manufacturer thus eliminating any possibility of workmen being contaminated by diseases or the like which could be conveyed to the manufacturing plant on the returned mattress. lt is a simple matter to disconnect a damaged cell and replace it with a new cell since this may be done without removing the pad from the bed and causing minimal disturbance to the patient and with a very small cost in time and material used.

Still another object of the present invention is to provide an alternating pressure pad having independent cells interconnected by a strap structure which also serves to retain the pad in place on a hospital bed mattress or the like and which is extremely simple in construction, long pasting and durable, easy to repair by replacing independent cells, effective for the purposes of relieving pressure points and preventing bedsores and still relatively inexpensive to manufacture.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a plan view of the pressure pad of the present invention installed on a mattress such as that employed on a hospital bed;

FIGURE 2 is a longitudinal sectional view of the pressure pad illustrating its relationship to the mattress and taken substantially on a longitudinal section line;

FIGURE 3 is a sectional view taken substantially along section line 3 3 of FIGURE 2 illustrating the association of the end strap with the loops formed in the ends of the independent cells;

FIGURE 4 is a transverse sectional view taken substantially upon a plane passing along section line 4 4 of FIGURE 2 illustrating the intermediate retaining strap and its association with the independent cells or tubes and the mattress;

FIGURE 5 is a sectional view taken along section line 5 5 of FIGURE 2 illustrating the heel supporting structure and its association with the independent cells;

FIGURE 6 is a detailed sectional view taken generally along section line 6 6 of FIGURE l illustrating the specific construction of the connecting assembly employed between the manifold and one of the air tubes;

FIGURE 7 is an enlarged fragmental sectional view illustrating the association of the deflated tubes and the inflated tubes; and

FIGURE 8 is a detailed sectional view of another arrangement for anchoring the head ends of the tubes.

Referring now specifically to the drawings, the alternating pressure pad of the present invention is generally designated by the numeral 10 and is illustrated as being mounted on a conventional mattress structure such as that employed in a hospital bed and supported by a spring assembly 14 supported from a peripheral frame i6 which in turn is supported from a headboard 18 and a footboard 20 of conventional construction. The alternating air pressure pad may be supported on a conventional hospital bed or on any other type of bed.

The pad 10 includes two sets of air tubes or air cells and for purposes of description are designated by numerals 22 and 24 with it being understood that the tubes or cells are identical in construction and adjacent tubes or cells are alternately inflated and deflated. As illustrated in FIGURE 7, the cells 22 are inflated while the cells 24 are deflated and as illustrated in that figure and in other figures of the drawings, the cells or tubes 22 and 24 are independent of each other throughout their longitudinal length.

For retaining the tubes or cells 22 and 24 in an assembled pad, one 0r more retaining strap assemblies 26 are employed. Each retaining strap assembly includes an elongated strap member 28 of flexible material which extends across the mattress 12 and includes downwardly extending portions 30 which extend under the mattress 12 and are secured together by buckles 32. Attached to the strap 28 is a plurality of retaining straps 34 which are of inverted U-shaped configuration for extending over and around the periphery of the cells 22 and 24 as illustrated in FIGURE 4. The straps 34 may be of the same material as the tubes and will collapse with the tubes when the tubes such as tubes 24 are collapsed. The straps 34 snugly embrace the inflated tubes 22 and 24 and are relatively thin and actually press into the cell surface s0 that no projections are formed on the top surface of the pad. When one of the tubes 22 and 24 is to be removed, it will be deflated and may be removed longitudinally through the loops formed by the straps 34 attached to the strap 23. The strap 2S may terminate at the top corners of the mattress 12 except when unusual bed positions must be employed. While there have been two rctaining strap assemblies 26 illustrated, more or less of the retaining strap assemblies may be employed if desired.

The head ends of the tubes 22 and 24 are closed by doubling the end of the tube into a loop 36 and tying it to itself by the use of a knot 38 so that each tube has a loop 36 formed on the head end thereof. A retaining strap 4l) extends through the loops 36 and has the ends thereof extending downwardly alongside of the mattress as at 42 and then extending under the mattress as at 44 with the ends thereof being suitably interconnected by a suitable buckle or the like. At a plurality of points on the strap 40, end straps 46 are attached which extend around the end of the mattress 12 as illustrated at 48 with the ends of the end straps 46 being attached to the underlying portion of the strap 40 by suitable stitching 50 or the like. As illustrated in FIGURE 3, a suitable buckle or hook device 52 may be provided for connecting the ends of the underlying portion 44 of the strap 4t) together thus preventing longitudinal movement of the pad 10 when the mattress 12 is folded or elevated when the device is used on a hospital bed or the like.

Extending transversely of the pad 10 adjacent the foot end thereof, there is provided a transversely extending heel raising tube 54 which has a loop S6 formed on one end thereof for looping around the outermost tube 22 at one edge of the pad. The loop S6 is formed by securing a portion of the terminal end portion of the tube 54 to itself as at 58 by heat sealing or by employing a knot or the like. The other end of the tube 54 is provided with a tube 60 which extends between adjacent air tubes or cells 22 and 24 and under the outermost air tube or cell 22 remote from the other outermost air cell or tube 22 as illustrated in FIGURE 5. The tube 54 may be moved longitudinally of the pad and is placed under the patients ankles. By alternately inflating and deflating the tube 54 it will lift the heel thus permitting adequate blood flow to the critical heel area. A unique advantage of the separate heel protecting cell is the fact that it can be moved toward the head or foot of the bed as necessary to fit short or tall patients.

Each of the tubes 22 and 24 is connected to a manifold 62 and 64 respectively with one of the manifolds such as the manifold 62 having the tube 60 to the heel raising cell 54 communicated therewith. The manifold 62 is also a plastic tube having smaller tubes or sleeves 66 integral therewith for receiving a tubular connector 68y which has a larger diameter area 70 received in the neck 72 of the tube 22. Both portions of the connector 63 are provided with peripheral serrations 74 which are inclined towards the longitudinal center of the connector 68. The serrations 74 on the larger diameter area 70 receive and retain liquied surface hardenable sealant 76 and a pair of spaced rings 78 in the form of split spring rings encircle the neck 72 in spaced relation to retain at least the central portion of the sealant 76 in a fluid or liquid condition. The sleeve 66 and a single or pair of spring rings is provided for anchoring the connector 68 in the sleeve 66 in a sealed manner. The split spring rings may be easily removed by a suitable tool and in order to prevent any possible entanglement of the bedcloths with the split rings, a sealing tape may be positioned over the split spring rings which are constructed of spring steel or the like. T'he air tubes 22, of course, are of the same diameter throughout their length and are gathered around the enlarged end portion 70 of the connector 68 with the fluid filler or sealant 76 serving to completely fill and seal any crevices which would permit leakage of air thus providing a positive seal and yet one which is easily formed.

The cells or tubes 22 and 24 are alternately inflated and deflated from an air compressor and control assembly generally designated by numeral 80 which is mounted on the footboard 20 in any suitable manner such as by a spring clip assembly `82. The details of the air compressor and control assembly 80 forms no particular part of the invention disclosed in this application but it does include a male plug an-d electrical conductor 84 so that it can be plugged into any suitable electrical outlet. In addition, there is provided a pair of tubes 86 and 88 whic'h are connected to the manifolds 62 and 64 respectively for alternately inflating and deflating the sets of cells or tubes 22 and 24. The air which egresses from the deflating cells is discharged through a third tube 90 which discharges to an underpad disposed bel-ow the alternating pressure pad and which also is not specifically disclosed in this application.

In operation, the a-ir compressor and control assembly 80 will alternately inflate one set of cells 22 while deflating or exhausting air from the other set of cells 24 and then subsequently inflate the set of cells 24 and deflate the cells 22 in a manner where the inflated cells 22 are not deflated until such time as the deflated set of cells 24 have been fully inflated. In the drawings, all of the cells have been shown inflated except for FIGURE 7 where the relationship of t'he cells is illustrated.

One of the unique advantages of the pad of this invention is its capability of inflation and deflation without -pad distortion and the deflated cell is independent of the inflated cell so that the deflated cell will not become taut between adjacent inflated cells and thus continue to form a pressure point against the patients body. Also, as indicated in FIGURE 7, the air tubes or cells may flex downwardly to conform with bony prominences of the patients body thus supportingly engaging a larger area of the patients body while yet spacing the patients body from any pressure engagement with the underlying mattress thereby enabling a lower pressure to be employed in floatingly supporting a patient due to the larger diameter of the tubes which may be approximately two inches. The pad is constructed of a film which may be considered a nonplasticizing lm such as Ultrathene which prevents plastic deterioration due to aging or temperature elevation.

FIGURE 8 illustrates a modified anchoring structure which may be used at the head end -of the tubes or cells 22 and 24 in lieu of the loops and knots and also in lieu of the loop 56 on the end of the heel raising tube 54. This structure includes a tube 92 which is gathered around and sealingly connected to a connector 94 by spring rings 96 and sealant 98 similar to the connector in FIGURE 6. Disposed in the connector 94 is a wire anchor 100 sealed into the connector by surface hardenable sealant 102. The inner end of the wire anchor 100 is provided with a retaining loop 104 which is also covered by the sealant thus preventing leakage around the wire anchor 100. The outer end -of the wire anchor is reversely bent to form a hook or clip 106 closely overlying the serrated reduced end portion of connector 94 for releasably securing a flexible anchor strap or tie strap 108 thereunder for securing the strap to the end of the tube so that the tubes 22 and 24 may be anchored to the mattress and tube 54 secured to the pad.

Pressure pads from their inception approximately l5 years ago have been designed with tubes not in excess of 1%." in diameter when inflated. When such small diameter tubes are used, it is necessary to inflate them to over 80 mm. of mercury pressure to prevent most patients from bottoming on the mattress in the areabetween the inflated tubes. These high pressures still do not prevent some patients from bottoming and they also increase tube hardness to such an extent that all patients find them uncomfortable. In order to prevent bottoming of all patients and to maintain supporting contact between the cell and body throughout their adjacent length, a cell diameter of at least 11/2 is necessary. Small diameter cells can prevent bottoming if sufliciently high pressures are used but the cell becomes so stiff that supporting contact throughout the adjacent length of the cell and body is not possible.

The independent tubes enable assembly thereof from tubular material which may be commercially obtained in whatever length desired or may be obtained in roll form and severed into desired lengths thereby enabling the overall length of the pad to be varied depending upon the individual needs. This construction also enables ease of replacement of the individual tubes. The independence of the tubes from each other provides a breathing action for the patient, that is, there is a capability of air passing between the tubes substantially throughout the entire length thereof which is not possible with the presently available pads. By increasing the diameter of the cells to 1% in diameter when inflated, the depth of the air cushion is increased thereby allowing a lower air pressure to be used which permits supporting contact of the cell with the body over substantially its total length. Due to the increased depth of the air cushion, the bony protuberances may extend further below the means supporting level of the inflated cell before bottoming on the mattress. The combination of lower air pressure and deeper air cushion permits the cell to conform to the body shape resulting in a more evenly distributed and larger area of supporting contact. This also results in a far more comfortable pad for the patients.

When the large diameter and independent tubes are used, the alternate inflation and deflation of adjacent tubes produces an air circulation under the patient. As will be apparent in FIGURE 7, the air above the deflated tubes 24 will be displaced as they are inflated and correspondingly when the inflated tubes 22 are deflated, fresh cooling dry air will then flow into the area previously occupied by the inflated tubes. This not only adds to the patients comfort but more importantly helps to keep the weeping pressure sores dry and materially reduces recovery time.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. An alternating pressure pad comprising a plurality of flexible, imperforate tubes orientated in side-by-side relation throughout their length, said tubes being completely free of each other throughout their length and exposed directly to a patient thereby defining a completely unobstructed top surface to directly supportingly engage a patient, means communicated with one end of said tubes for enabling alternate inflation and deflation of interdigitated sets of tubes, means connected adjacent tubes along a small portion of the length thereof for retaining the tubes in side-by-side relation, said means leaving the major portion of the upper periphery of the tubes free of restriction and enabling lateral deflection of the upper portion of the tube when supportingly conforming with the body Iof a patient.

2. The structure as defined in claim 1 together with a heel raising tube extending transversely of the side-byside tubes and being adjustable longitudinally thereof for alternately elevating the heels of a patient from contact with the pad.

3. The structure as defined in claim 1 wherein each of said tubes is in the form of a flexible tubular member having a loop formed in one end thereof, and retaining means extending through the loops for retaining the tubes in side-by-side relation.

4. The structure as defined in claim 1 wherein said means connected to adjacent tubes includes a relatively narrow strap extending transversely of the tubes in underlying relation thereto, and narrow retaining loops of liexible material connected with the strap and extending over the top of each tube for retaining the tube against the strap and enabling lateral deflection of the tube whereby the loops are commensurate with the tubes as to tieX- ibility and supporting engagement with the body of the patient.

5. The structure as dened in claim 3 wherein said retaining means includes end straps adapted to engage the the end of a mattress to prevent movement of the pad in relation to a mattress.

6. The structure as defined in claim 1 wherein said tubes having a diameter forming an air cushion when inflated of suicient depth to maintain supporting Contact substantially throughout adjacent length of the cell and body of the patient.

7. The structure as defined in claim 6 wherein said tubes have a diameter of not less than 1%." when inated with the air pressure being not in excess of 60 mm. of mercury.

References Cited UNITED STATES PATENTS 640,985 1/1900 Aylmer 5-348 X 1,456,207 5/1923 Adamski 5-348 X 1,772,310 8/1930 Hart 5-348 X 2,998,817 9/1961 Armstrong 5-349 X 3,008,465 11/1961 Gal 5--60 X 3,288,133 11/1966 Little 5-349 X 3,303,518 2/1967 Ingram 5-349 2,819,712 1/1958 Morrison 5-348 X FOREIGN PATENTS 1,023,097 3/ 1966 Great Britain.

20 BOBBY R. GAY, Primary Examiner.

A. M. CALVERT, Assistant Examiner.

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