"FABRIC FOR THE PRODUCTION OF HEAT-REGULATING ITEMS TO MAINTAIN BODY TEMPERATURE AND A HEAT-REGULATING BLANKET MADE FROM THIS FABRIC" TECHNICAL FIELD
This invention relates to a fabric suitable for making products for regulating the temperature of the body which can be used in health and health-related settings. More particularly, this invention relates to a fabric thanks to which it is possible to produce a blanket for regulating the temperature of the body which can be used mainly even if not exclusively in health structures, that is to say, in hospital wards and operating rooms.
Even more particularly, this invention relates to a blanket for regulating the temperature of the body of a patient which allows this temperature to be kept as constant as possible and which does not decrease below a safety threshold.
The blanket for regulating the temperature of the body according to the invention was designed to overcome the problems generated by hypothermia in patients undergoing surgery in operating rooms, in particular for lengthy operations.
With respect to prior art solutions, the blanket for regulating the temperature of the body according to the invention, makes it possible, thanks to its intrinsic features, to maintain the same temperature of the body about 37 °C independently of the room temperature: in the case of excessive body heat, the blanket cools the body, and vice versa, in the case of low body temperature, it heats the body.
The blanket for regulating the temperature of the
body according to this invention applies to the health sector and can be used mainly even if not exclusively in health structures, that is to say, in hospital wards and in operating rooms.
BACKGROUND ART
It is known that in the health sector and in particular in operating rooms and in hospital wards, it may be necessary to keep the temperature of patients constant, for example patients who must undergo surgery and in particular sedated patients.
All patients who must undergo surgery under anesthesia are covered up in order to limit the lowering of the temperature of the body and to best deal with the problem of involuntary intra-operative hypothermia in adults .
Involuntary intra-operative hypothermia is a significant problem, and may be the source of even severe complications, considering that the mortality of patients with moderate or severe hypothermia is around 40%.
During surgery, hypothermia, a "basic" body temperature lower than 36°C, is caused by various factors :
• anesthetics;
· infusion of liquids, gases or blood products administered at ambient temperature;
• dispersion of heat through the surface of the body and the surgical site, that may at times be extensive, towards the outside environment;
· the standards of the ambient temperature in an operating room, which are between 20°C and 24°C. To overcome these problems, various covering systems
are used in operating rooms, in hospital areas such as reanimation, intensive care, nephrodialysis , accident & emergency, in ambulances, in nursing homes, and in assisted home-care settings. The aim of these systems is to keep the temperature of the patient constant, and to prevent, in particular, the temperature falling below the threshold levels which could become harmful for the body.
These systems include heat-transmitting mattresses and more advantageously thermal blankets, whose heat source may be supplied by a suitable device that sometimes may be integrated with a heating system or it may be obtained by using suitable materials.
The use of traditional thermal blankets has revealed some limitations which make their use not very practical; such limitations which, in the case of an integrated heating system for example by hot air cells, may be production complexity and the need to use complex auxiliary equipment to supply and deliver the heat.
Solutions concerning thermal blankets based on the principle of heat-transmitting materials suffer from the limitation that these materials are not sufficiently advanced in terms of quality, and, for example, cotton is used with results which remain rather far from expectations .
Document DE 20 2007 001 699 Ul discloses some textile structures useful in bedding articles e.g. blankets, pillows, mattresses, mattress cover, bed clothes, or fillings or wrappings, made of fibers, non- woven, fabrics, knitted fabric or knotted fabric, having a multi-layer construction. The bedding articles are producible by a part of cellulosic phase changing material (PCM) -fiber that regulates and balances the heat flow from a resting body to the environment. As the PCM- fiber, a molded part with reincorporated paraffin part
produced after the lyocell or viscose method, is used.
Document US 2010/0088818 Al discloses a cover for mattress having a reclining surface of viscoelastic foam having a fabric body with a first surface disposed in engagement with the reclining surface; an opposite, second surface disposed for engagement by a person reclining upon the cover, and at least one air flow region defined by the fabric body for enhanced circulation of air between the reclining surface of viscoelastic foam and an opposed skin surface of the person reclining upon the cover. The circular knit fabric body comprises a flame retardant material.
DESCRIPTION OF THE INVENTION
The aim of the invention is to provide a heat- regulating fabric designed to regulate the temperature of the body, which can be used mainly even if not exclusively in health structures, that is to say, in hospital wards and in operating rooms, but which may also be used in the home, and in hotel and sports settings, which is able to overcome, or at least reduce the drawbacks described above.
The invention also aims to provide a blanket for regulating the temperature of the body, for example in the typical case of involuntary intra-operative hypothermia, which is relatively easy to make as it is based on materials designed to maintain the heat of the body .
This is obtained by a fabric for regulating and maintaining the temperature of the body, whose features are described in claim 1.
The dependent claims describe advantageous forms of embodiment of the invention.
The main advantages of this solution, besides all those deriving from the constructional simplicity, relate
first of all to the fact that the blanket is designed to overcome the problems generated by hypothermia in patients undergoing surgery in operating rooms, in particular for lengthy operations, and which, thanks to its intrinsic features makes it possible to maintain the temperature of the body around 37 °C regardless of the room temperature: in the case of excessive body heat, the blanket cools the body and, vice versa, in the case of a low temperature, it heats the body.
Thanks to the features of the fibres which make up the fabric with which it is made, the heat-regulating blanket according to the invention achieves the required performance without the use of accessories or external means, retaining its characteristics unaltered for the entire duration of the life cycle of the product.
DESCRIPTION OF THE DRAWINGS
Other features and advantages of the invention will become clear on reading the description given below of one embodiment, provided as a non-limiting example, with the help of the accompanying drawings, in which:
figure 1 is a schematic perspective view of the three layers which make up the fabric according to the invention, in particular for making a blanket; figure 2 is a schematic view of a blanket shown in cross section and with the three layers separate; figure 3 is a schematic view of the blanket with the three layers coupled together. DESCRIPTION OF A PREFERRED FORM OF EMBODIMENT
OF THE INVENTION
With reference to the accompanying drawings, a heat- regulating blanket according to this invention is made of
a fabric 10 consisting 50% to 70% of polyester and 30% to 50% of viscose , and has the features described below:
Active heat-regulation;
Transpirability;
· Antibacterial;
Ability to absorb and eliminate natural humidity (perspiration) ;
It is soft and fresh to the touch;
It manages heat during sleep.
With reference to a feature of the invention, during extrusion of the filament of the fabric 10 a predetermined quantity of microcapsules, containing a Phase Change Material, is inserted in the fabric. These microcapsules act as heat-regulators, absorbing any excess heat and releasing it when necessary, thus creating a constant microclimate.
More precisely, the first layer of the fabric of the blanket according to the invention is made from 50% to 70% of polyester and 30% to 50% of viscose , and does not contain environmentally harmful substances.
The fabric 10 generally weighs from 300 to 350 grams per m2 and is 200 to 215 cm wide. The roll varies in length according to loading and transport requirements.
The fabric 10 according to the invention consists of 3 layers of different fabrics and, more specifically:
The inner layer 11 which comes into contact with the person, either directly on the skin or indirectly with a sheet in between, is made from Viscose . This layer regulates the temperature thanks to the Phase Change Material present in the Viscose fibre, which traps the heat when it is emitted by an over-heated body and releases it when the body tends to cool down, thus
keeping the temperature of the person constant. According to an advantageous embodiment of the invention, the Viscose fibre used to make the blanket according to the invention is cellulose-based and is produced starting from wood pulp.
This fibre gives the fabric excellent softness and a pleasant sensation of freshness. Thanks to its molecular structure with nanofibrils, it absorbs 130% of steam and 50% of moisture more than pure cotton. This feature also means that steam and moisture are quickly released externally so that the surface of the fabric always stays fresh and dry. The Viscose® fibre effectively counters the proliferation of bacteria thanks to the perfect control of humidity and the microclimate created inside its structure.
1. The intermediate layer 12 made with 100% polyester fibre padding which allows quick release of the humidity produced by the body as perspiration, maintaining a condition of well-being and preventing the proliferation of bacteria.
2. The outer layer 13 made from 100% coloured polyester, providing the blanket with an attractive finish .
With reference to the invention, the three layers 11, 12 and 13 are joined to each other to form the fabric 10 thanks to a single processing with a circular knitting machine; the three layers are coupled together solely through the yarns themselves which join one layer to the next, avoiding the use of glues or other binders.
According to a preferred embodiment, the finished product looks like a padded blanket and this provides greater comfort compared to a simple monolayer fabric which would be less thick and therefore less comfortable,
but would also have a reduced performance as well as less appeal in terms of softness and appearance.
The intermediate layer 12 of the polyester fibre padding makes it possible to create an air cushion, and serves to eliminate moisture and perspiration, as well as assisting temperature regulation.
The outer layer 13 of coloured polyester outer is non-absorbent and this facilitates the transfer and elimination of perspiration and humidity towards the outside.
The inner surface 11 in contact with the patient is thus always fresh and dry.
The phase change material is in the form of paraffin-based microspheres, and is inserted in the heart of the fibres, therefore more protected and resistant to washing .
It is known that this material is able to activate a phase change similarly to the physics principle of evaporation or water solidification when heat is added or removed.
In the case of the phase change material used for the purposes of this invention, it should be noted that conventional insulators retain the heat and humidity, increasing body discomfort, whilst the thermal adjustment which occurs thanks to the use of a phase change material is an interactive process of perpetual comfort management: absorption, maintenance, distribution and diffusion of body heat by the phase change material embedded in fibres and fabrics. It reduces the sudden changes of temperature and humidity close to the skin, eliminating unpleasant sensations, irritability, tiredness, and a general feeling of discomfort.
The first Viscose fibre with embedded phase change
material offers all the benefits of normal viscose , such as, for example, softness, smooth to the touch - similar to cotton or to silk - and extreme comfort, and at the same time regulates the temperature thanks to the properties of the phase change material.
The Viscose fibre with the embedded phase change material is a cellulose-based material and can be combined with any other type of fibre: from cotton to polyester and polyamide, to technical fibres such as aramide. Thanks to the features of the fibres which make up the fabric with which it is made, the blanket achieves the performance required without the use of accessories or external means, maintaining its characteristics unaltered for the entire duration of the life cycle of the product.
The first layer of the fabric according to this invention, consisting of Viscose fibre with embedded phase change material, may be used to make various articles for health sector use, such as for example:
· Operating room drapes in various sizes and for various types of surgical procedures;
Jackets and vests for operating rooms with relatively low temperatures;
Accessories such as shrugs or stoles for operating room surgical teams;
Bed covers for stays in hospital wards or nursing homes ;
Overalls for residents of nursing homes/old people's homes .
EXPERIMENTATION
The fabric according to this invention, in the form
of a temperature-regulating blanket, was subjected to a number of tests and the results confirmed the capacity to adjust the temperature of the body in patients undergoing surgery. The results of a test of this type are shown below.
The Study: A thermal blanket was tested for covering patients undergoing surgery followed, in some cases, by a stay in the ICU.
Aim: To maintain a stable body temperature of patients undergoing surgery followed, in some cases, by a period in the ICU.
Background art: systems which produce heat, such as electrical heaters and/or inert materials such as metalline, are normally used to keep patients warm.
Period of the study: 3 months.
Study sample: The thermal blankets for temperature regulation were placed over 15 patients undergoing surgery .
The operation was performed under general anesthesia in 6 patients and under spinal anesthesia in the other 9.
The surgery lasted between a minimum of 40 minutes up to a maximum of 330 minutes.
The body temperature was measured with an external cutaneous probe in 3 patients, with a pharyngeal probe in 1 patient and with a digital axillary thermometer in the remaining 11.
The body temperature was measured at 3 specific time points of the operation: at the start, at the halfway stage and at the end.
The temperature remained the same as at time 0 (start of the operation) in 3 patients, it increased in 5 patients, while the temperature reduction in 6 patients
cannot be considered as significant. In 1 case only, the temperature decreased by 2°C, with respect to time 0, and returned to normal after a period in the Intensive Care Unit ICU.
5 · The comfort of the thermal blanket was always
judged by the patients as positive.
Patients transferred to the ICU for 24 hours after surgery expressed their greater appreciation of the thermal blanket compared to traditional covering systems, 10 it being much softer and breathable, thus preventing
perspiration .
The table below provides a summary of the test.
OPERATING SURGICAL TEMPERATURE HALF DURATION ICU
ANESTHESIA START END Δ COMFORT ROOM PROCEDURE MEASUREMENT WAY (MINUTES) STAY
INTESTINAL PHARYNGEAL
SURGICAL GENERAL 36.2 36.0 36.0 -0.2 290 36.8 POSITIVE
RESECTION THERMOMETER
CAESAREAN CUTANEOUS
OBSTETRICS SPINAL 34.3 35.2 35.2 0.9 65 POSITIVE
SECTION PROBE
SIGMA RESECTION BY CUTANEOUS
SURGICAL GENERAL 36.0 35.0 34.0 -2.0 150 36.8 POSITIVE
VIDEO- PROBE
LAP AROSCOPY
TRACHEOTOMY WITH LATERO- CERVICAL CUTANEOUS
ENT GENERAL 33.3 34.0 34.1 0.8 330 35.6 POSITIVE
EMPTYING PROBE BILATERAL HEMI- LARYNGECTOMY
CAESAREAN CUTANEOUS
OBSTETRICS SPINAL 36.1 36.6 36.3 0.2 60 POSITIVE
SECTION PROBE
DIGITAL
THROMBO-ENDO-
SURGICAL GENERAL AXILLARY 36.2 36.0 36.0 -0.2 120 36.2 POSITIVE
ARTERECTOMY THERMOMETER
DIGITAL
ORTHOPAEDI HIP
SPINAL AXILLARY 36.2 35.8 35.6 -0.6 240 36.0 POSITIVE CS REPLACEMENT THERMOMETER
DIGITAL
CAESAREAN
OBSTETRICS SPINAL AXILLARY 36.0 35.8 36.0 0.0 40 POSITIVE
SECTION THERMOMETER
PROSTHESIS DIGITAL
SURGICAL POCKET GENERAL AXILLARY 33.8 34.0 34.0 0.2 165 POSITIVE
REVISION THERMOMETER
DIGITAL
ORTHOPAEDI TOTAL HIP
GENERAL AXILLARY 36.5 36.0 36.0 -0.5 120 POSITIVE CS REPLACEMENT THERMOMETER
DIGITAL
SURGICAL HERNIOPLASTY SPINAL AXILLARY 36.3 36.4 36.3 0.0 55 POSITIVE
THERMOMETER
DIGITAL
SURGICAL SAPHENECTOMY SPINAL AXILLARY 36.6 36.5 36.6 0.0 50 POSITIVE
THERMOMETER
DIGITAL
SURGICAL HERNIOPLASTY SPINAL AXILLARY 36.6 36.5 36.5 -0.1 45 POSITIVE
THERMOMETER
DIGITAL
SURGICAL SAPHENECTOMY SPINAL AXILLARY 36.4 36.5 36.5 0.1 45 POSITIVE
THERMOMETER
DIGITAL
SIGMA
SURGICAL GENERAL AXILLARY 36.2 36.0 36.0 -0.2 120 36.2 POSITIVE
RESECTION THERMOMETER
The thermal blanket according to the invention has further features not perceived by the patient, but appreciated from the care point of view, because it drapes well, that is, it remains adherent to the body of the patient unlike other systems such as "metalline", and in addition, being reusable, the product does not produce health waste.
According to a further embodiment of the invention, the heat-regulating fabric may also be made substantially fireproof, in particular by using:
- for the first layer 11, a fireproof yarn combined with the Viscose® fibre and the phase change material;
for the second padding layer 12 (intermediate layer) , a Flame Retardant material such as Polyester Dtex 668; and
- for the outer layer 13, a Flame Retardant Dtex 167 coloured Polyester.