[0001] The bed is the element with which the hospitalized patient is in closest contact
in the hospital environment.
[0002] It frequently occurs, especially in the cases of a prolonged stay in hospital with
continuous confinement to bed, both in the acute phase of illness and in the subsequent
phase, that decubitus ulcers form in areas of the body that are at greater risk of
developing them, in particular, in the sacral part and in areas corresponding to the
patient's heels.
[0003] There currently exist on the market only air mattresses or water mattresses (full-flotation
beds), which, however, function only as a palliative and substantially have the function
of preventing formation of decubitus ulcers, but not that of healing them after they
have developed.
[0004] Consequently, the prevention and treatment of trophic sores resulting from confinement
to bed represent, in the domestic and hospital context, an important problem of health
care, which requires a considerable commitment in terms of human and economic resources,
as well as of materials and technologies.
[0005] By " decubitus ulcer" or "pressure sore" resulting from confinement to bed is meant
a tissue lesion presenting a necrotic evolution that involves the cutis, the derma,
and the subcutaneous layers, until, in more serious cases, the muscle, the cartilage
and even the bone are affected.
[0006] The phenomenon is caused by a prolonged and/or excessive pressure exerted between
the resting surface and the surface of the bone, such as to cause a mechanical stress
on the tissues and an alteration of the local blood circulation. Clinically, the lesions
are noted in sites that are particularly predisposed, such as the bone prominences
(sacrum, heel, olecranon, trochanter) and arise as a result of prolonged confinement
to bed in an obligate position. Consequently, they tend to form prevalently in subjects
affected by pathological conditions that jeopardize their neuromotor functionality
and, in elderly bedridden subjects, above all if they are affected by systemic diseases,
such as diabetes mellitus, renal insufficiency, immunodepression, circulatory disorders,
etc., which constitute a further aggravating circumstance.
[0007] The principal physiopathological mechanisms that determine onset of decubitus ulcers
are pressure and shear. Other conditions that perform a concomitant role are rubbing
and moisture.
[0008] The pressure exerted on the tissues is considered the principal pathogenic factor.
[0009] The normal pressure in the arterial capillary circulation is 32 mmHg.
[0010] The external compression becomes harmful for the tissues when it exceeds the critical
level of 32 mmHg, since it leads to a reduction in the arrival of blood, with consequent
ischaemia and hypoxia.
[0011] The effects of compression vary not only according to the intensity and duration
of the compression but also according to the site, the thickness of the cutis and
of the soft tissue. It has been demonstrated, for example, that a pressure of 60-70
mmHg sustained for two hours may be sufficient to produce an irreversible injury.
[0012] If the cutaneous tissue is able to respond to the insult caused by the compression
with a compensatory hyperaemia, in elderly patients this is generally insufficient
to protect it from the risk of hypoxia.
[0013] In the absence of oxygen, the cells use an anaerobic metabolism, which produces toxic
substances and local acidosis, increase of vasal permeability, formation of transudate
and oedema, as well as further cellular suffering, up to necrosis.
[0014] Shear forces determine a progressive mutual displacement of surfaces constituted
by elements set on top of one another.
[0015] Said forces occur, for example, either when the bed head is raised, with the tendency
of the trunk of the body to slide down and the segments of the body of the patient
to slip from one position to another. In these cases, a pulling action is exerted
on the soft surface tissues anchored by the deep muscular fasciae, with the effect
of stretching, possible angulation, microthromboses, obstruction and recision of the
small vessels, hypoxia, and consequent deep-tissue necrosis.
[0016] Rubbing, albeit not presenting a major pathogenic role, determines removal of the
more superficial layer of the skin, the corneal layer, with consequent reduction of
the fibrinolytic activity of the derma, rendering the latter more susceptible to necrosis
resulting from compression.
[0017] Moisture intensifies the action of the other factors because it renders the skin
more brittle and more subject to assault. A prolonged exposure of the cutis to moisture
causes phenomena of maceration and alteration of the pH, thus reducing the barrier
function performed by the cutis itself.
[0018] A first purpose of the present invention is to provide an innovative mattress that
is able to prevent formation of decubitus ulcers.
[0019] A second purpose of the invention is to heal said ulcers in the case where they have
formed.
[0020] This has been obtained, according to the invention, by providing a medical device
comprising a modular mattress provided with means for forced aeration of the areas
of the body presenting sores or subject to developing sores.
[0021] A better understanding of the invention will be obtained from the ensuing detailed
description with reference to the attached figures, which illustrate, purely by way
of non-limiting example, a preferred embodiment thereof.
[0022] In the drawings:
Figure 1 is a top plan view of the invention, which shows the principal parts of the
mattress;
Figure 2 is a 3D view that shows further details of the invention, in which the ducts
for the oxygen are further highlighted;
Figure 3, which is similar to the previous one, shows the case where a spacing element
is positioned between the sacral area and the legs of the user;
Figure 4, which is similar to the previous one, shows different spacer sizes;
Figures 5 and 6 are 3D views that show the invention with removable cover;
Figure 7 represents activated-carbon filters for elimination of odours;
Figures 8 and 9 show the size of the cavities and of the means for collection of the
colliquation material of the decubitus ulcers;
Figures 10 and 11 are a perspective view and plan view, respectively, of the means
for resting of the patient's feet on the respective anti-ulcer cavities; and
Figures 12-14 show the sequence of installation of said means for resting of the patient's
feet in their own site.
[0023] In the light of the physiopathological mechanisms referred to above that determine
onset of the decubitus ulcers, the invention is substantially constituted by a modular
and adjustable mattress, which is provided with means for forced aeration of the areas
of the body more subject to formation of decubitus ulcers, such as, for instance,
the sacral area and the area of patient's heels, which is made of a particularly soft
spongy material and envisages cavities in areas corresponding to parts of the body
that are subject to risks of developing decubitus ulcers.
[0024] Even though the mattress may be made of a single piece, the preferred embodiment
described herein is made up of at least three parts or modules: a top module A, a
central module B, and a bottom module C.
[0025] The top module A is designed to provide a support for the head and the shoulders
of the bedridden patient.
[0026] According to the invention, the central module B is provided with a hole or cavity
FS in an area corresponding to the sacral area, whilst the bottom module C is provided
with two holes or cavities FT in an area corresponding to the patient's heels.
[0027] The distance between the head and the sacral cavity FS and the distance between this
and the cavities provided for the heels FT can be adjusted, according to the structure
of the patient's body, by interposing between the modules A, B, C so far described,
the purposely designed spacers D. In this way, it is advantageously possible to adapt
the mattress to the body of the patient.
[0028] As has already been mentioned previously, the inventive idea underlying the present
invention substantially consists in guaranteeing a forced aeration to the areas of
the body that are susceptible to developing decubitus ulcers. For this purpose, according
to the invention, the sacral cavity FS and the cavities for the patient's heels FT
are provided with at least one inlet duct from which oxygen arrives and at least one
outlet duct from which the oxygenated air leaving the area presenting sores exits
to guarantee a continuous change therein.
[0029] It should in fact be noted that, with the configuration just described, the cavities
in an area corresponding to the ulcers form, around each of them, a sort of "fluid-tight
chamber", which is defined laterally by the walls of the cavities, at the top by the
surface of the body of the patient, and at the bottom by the surface on which the
mattress rests.
[0030] Basically, within each of the "fluid-tight chambers" that are positioned in an area
corresponding to the sores, there is prevalently an atmosphere with a high concentration
of oxygen, which is higher than 80% and preferably equal to approximately 99.9%, that
is delivered with the following characteristics:
- pressure: 1.03 bar
- temperature: 21±2°C
- humidity: 40-70%
[0031] In the example of embodiment described, the sacral cavity FS has a duct 11 for inlet
of the oxygen and five outlet ducts 1, 2, 11, 12, 13 arranged substantially in radial
fashion.
[0032] Likewise, each of the cavities FT corresponding to the patient's heels has a duct
12 for inlet of the oxygen and four outlet ducts 3, 4, 5, 6 and 7, 8, 9, 10, respectively,
arranged substantially in radial fashion.
[0033] Evidently, both the number and arrangement of the inlet/outlet ducts can be varied.
[0034] Said inlet/outlet ducts, embedded in the thickness of the mattress, are preferably
made of hard plastic material so as not to undergo any deformation with the weight
of the patient, thus guaranteeing proper inflow/outflow of the oxygen into/from the
cavity and hence into/from the area to be treated.
[0035] According to the present invention, in the case where the sores are not present,
the presence of the cavities for the sacral area and for the patient's heels advantageously
prevents their formation, whilst, in the case where the epidermis of the patient is
affected by decubitus ulcers, it is obtained that the transcutaneous increase in the
concentration of oxygen stimulates growth of new cells, with particular reference
to fibroplasts, essential for the synthesis of collagenase, as well as of new blood
vessels, which prove insufficient at the level of the necrotic areas of the lesions,
thus increasing release of endogenous oxygen.
[0036] In this way, tissue repair will proceed faster and above all will be more effective,
in particular ensuring safety of the system since it should be emphasized that, with
low-pressure topical oxygen therapy, there is no systemic absorption and hence no
risk for the cardio-pulmonary and nervous systems.
[0037] Finally, it should be noted that oxygen performs a bactericidal role for anaerobic
germs such as Staphylococcus aureus and E. coli.
[0038] Given that the oxygen that irrigates the necrotic and ulcered areas exits from the
mattress and is dispersed in the patient's room, it is evident that this causes diffusion
of unwholesome odours and the possible propagation of germs into the environment itself.
[0039] For this purpose, it is preferable to provide, in the terminal stretch of each outlet
duct from the sacral cavity or from the cavity corresponding to the patient's heels,
an activated-carbon filter FC of a known type.
[0040] Furthermore, the presence of a slight rise R at the level of the cervical dorsal
stretch in the top module A and the presence of supports for the ankles in the bottom
module C, together with the sacral holes or cavities FS and heel holes or cavities
FT, reduce the shear forces and rubbing of the skin over the entire surface of the
body.
[0041] For hygienic reasons, it is preferable to envisage also a small sac or bag CL for
the collection of the colliquation material of the sores, appropriately provided in
each of the cavities FC and FT. The sac is preferably impermeable to liquids and permeable
to gas to allow the oxygen to pass.
[0042] The walls of the holes or cavities have a certain stiffness to guarantee the presence
of a minimum volume for application of oxygen therapy to the ulcers. From the experiments
conducted, it has been possible to note that the minimum volume of said sacral cavity
FS and heel cavities FT is preferably 2512 cm
3.
[0043] The number and dimensions of the spacers D can be modified according to the requirements.
[0044] Finally, it should be noted that the moisture in the critical areas is substantially
eliminated thanks to the presence of the aforesaid holes or cavities and is reduced
in the remaining areas thanks to the transpirant capacity of the spongy material of
which the mattress is made.
[0045] The oxygen is preferably taken from the hospital supply system and, from what has
been said, is applied directly on the "exposed" ulcer, which has been previously cleaned
with physiological solution.
[0046] The oxygen therapy just referred to presents different therapeutic indications, amongst
which:
- phlebostatic sores and ulcers;
- sores and discontinuities of the skin in arteriopathic patients;
- wounds infected with mixed flora;
- sores or wounds or ulcers in diabetic patients;
- tissue lesions in patients undergoing cortisone therapy, as in the case of rheumatoid
arthritis or the like;
- infected and exposed bone lesions;
- skin transplants subject to risk owing to local or general conditions;
- burns that are infected or susceptible to risk of infection.
[0047] From the experiments conducted, the use of the invention has yielded excellent results
in the cases of patients affected by decubitus ulcers of different degree and deriving
from a wide range of pathological conditions. In all the cases treated, there has
been obtained: cleaning of the lesion, reduction of the diameters, clear evidence
of tissue granulation already starting from the third day of application, and above
all a reduction in the time required for healing corresponding to a saving of 35%-40%.
[0048] Adoption of the mattress according to the present invention envisages use of oxygen,
which must be appropriately humidified and delivered at a controlled temperature using
means of a known type.
[0049] The oxygen can also be supplied from a normal oxygen cylinder provided with means
known for regulating the pressure, temperature, and humidity.
[0050] The treatment of decubitus ulcers according to the invention varies according to
the type of the sore in question, the site, and the metabolic and psychosomatic conditions
of the patient.
[0051] In general, there is in any case recommended daily use thereof for approximately
4-5 hours up to complete healing.
[0052] There are no contraindications to the simultaneous use of hydrocolloids and antibioted
medicaments. Counter-indicated, instead, is manual curettage on account of the high
deobstruent and infective power that it can cause, contrary to the philosophy of the
treatment described herein.
[0053] Finally, it is preferable to provide a covering sheet that covers the three modules
and the possible spacers set between them, which is made of material impermeable to
liquids and transpirant for gases, bacteriostatic, and easy to clean. Said covering
sheet is provided with a bi-elastic cover that is transpirant and liquid-repellent,
which can be readily removed for washing thanks to a purposely provided zip, which
is completely hidden to prevent infiltration of any sort into the mattress itself.
[0054] Evidently, said cover is provided with lateral holes to enable exit of the oxygen
from the ducts extending from the sacral cavity FS and/or the cavities corresponding
to the patient's heels FT.
[0055] The present invention has been described and illustrated in a preferred embodiment
thereof, but it is clear that a person skilled in the branch may make technically
and/or functionally equivalent modifications and/or replacements thereto, without
thereby departing from the sphere of protection of the present industrial patent right.
[0056] For instance, a possible variant may regard the position and/or size and/or shape
of the holes or cavities in positions corresponding to the ulcered areas.
1. A medical device for healing and/or preventing decubitus ulcers, characterized in that it is provided with means for forced aeration of the areas of the body affected by
sores or subject to developing sores and substantially comprises a modular and adjustable
mattress, which is made of a particularly soft spongy material and envisages cavities
in areas of the body that present risks of developing decubitus ulcers.
2. The device according to the preceding claim, characterized in that the mattress is made up of at least three parts or modules: a top module (A), a central
module (B), and a bottom module (C).
3. The device according to the preceding claim, characterized in that the top module (A) is designed to provide a support for the head and the shoulders
of the bedridden patient, the central module (B) is designed to provide a support
for the central area of the body, and the bottom module (C) is designed to provide
a support for the lower limbs.
4. The device according to Claim 2, characterized in that the central module (B) is provided with a hole or cavity (FS) in an area corresponding
to the sacral region, whilst the bottom module (C) is provided with two holes or cavities
(FT) in the area corresponding to the patient's heels.
5. The device according to the preceding claim, characterized in that the distance between the head and the sacral cavity (FS) and the distance between
this and the cavities for the heels (FT) are adjustable, according to the corporeal
structure of the patient, by interposing between the top module (A) and the central
module (B) and/or between the latter and the bottom module (C) one or more purposely
provided transverse spacers (D); there thus being obtained the possibility of adapting
the length of the mattress to the body of the patient.
6. The device according to Claim 4 or Claim 5, characterized in that said means for forced aeration of the areas of the body subject to developing decubitus
ulcers envisage that the hole or sacral cavity (FS) and the holes or cavities for
the patient's heels (FT) are respectively provided with at least one inlet duct (11,
12), from which oxygen arrives, and at least one outlet duct (1-2, 11-13 and 3-10),
from which there exits the oxygenated air that leaves the cavity in the area where
decubitus ulcers are present in order to guarantee a continuous change therein.
7. The device according to the preceding claim,
characterized in that said oxygen supplied to the cavities in areas of the body presenting sores or presenting
risk of developing sores is designed to guarantee within the cavities (FS, FT) an
atmosphere with a concentration of oxygen equal to or higher than 80%, which is delivered
with the following characteristics:
- pressure: 1.03 bar
- temperature: 21±2°C
- humidity: 40-70%
8. The device according to the preceding claim, characterized in that the concentration of oxygen in the cavities (FS, FT) in areas of the body affected
by sores or presenting risk of developing sores is equal to approximately 99.9%.
9. The device according to Claim 6, characterized in that the sacral cavity (FS) has an inlet duct (11) for the oxygen and five outlet ducts
(1, 2, 11, 12, 13) arranged substantially in radial fashion.
10. The device according to Claim 6, characterized in that each of the cavities in an area corresponding to the patient's heels (FT) has an
inlet duct (12) for the oxygen and four outlet ducts (3-6 and 7-10) arranged substantially
in radial fashion.
11. The device according to Claim 6 or Claim 9 or Claim 10, characterized in that said inlet/outlet ducts, embedded in the thickness of the mattress, are made of hard
plastic material so as not to undergo deformation with the weight of the patient's
body, thus guaranteeing proper inflow/outflow of the oxygen into/from the cavity and
hence into/from the area to be treated.
12. The device according to Claim 6, characterized in that, in order to prevent diffusion of unwholesome odours and the possible propagation
of germs in the patient's room, provided in the terminal stretch of each outlet duct
(1-2, 11-13 and 3-10) coming from the sacral cavity (FS) and from the cavities for
the patient's heels (FT) is an activated-carbon filter (FC) of a known type.
13. The device according to Claim 3, characterized in that provided in the top module (A) is a slight rise (R) at the level of the dorsal cervical
stretch, and provided in the bottom module (C) are supports for the ankles in such
a way that, together with the sacral cavity (FS) and the cavities for the patient's
heels (FT), the forces of shear and rubbing of the skin are reduced over the entire
surface of the body.
14. The device according to Claim 4, characterized in that provided in each of the cavities (FC and FT) is a small sac or bag (CL) for collection
of the material of colliquation of the sores; the sac being impermeable to liquids
and permeable to gas to allow the oxygen to pass through.
15. The device according to Claim 4, characterized in that the side walls of the sacral cavity (FS) and heel cavities (FT) have a certain stiffness
to guarantee the presence of a space of minimum volume available for application of
oxygen therapy to the sores.
16. The device according to the preceding claim, characterized in that said minimum volume of the cavities (FS, FT) is at least 2512 cm3.
17. The device according to Claim 1, characterized in that the mattress is made of spongy material with high transpirant capacity.
18. The device according to Claim 6 or Claim 7 or Claim 8, characterized in that the oxygen is drawn from the hospital oxygen-supply system or from a cylinder, and
is appropriately humidified and brought to a temperature controlled with means of
a known type.