Patent Description:
The present invention also relates to a method for medical training associated with said device.

The performance of medical techniques and procedures, especially in the surgical field, usually requires great ability, continuous practice and wide expertise from the professionals who are responsible for carrying them out.

There are known in the state of the art several medical devices that allow professionals and potential professionals to repeatably carry out some medical techniques and procedures, so as they can get the necessary skills to perform them.

For example, <CIT> discloses an arm model apparatus for intravenous injection training. The apparatus is provided with a skin pad configured to be easily detachably mounted on a body of an arm model that imitates a human arm. The skin pad is formed as a triple-layered structure consisting of an epidermal layer, a dermal layer and a subcutaneous fat layer, or as double-layered structure consisting of an outer layer and a subcutaneous fat layer. A blood vessel-imitating tube is formed in the subcutaneous fat layer. The apparatus further comprises a pump drive unit that supplies liquid blood through the blood vessel-imitating tube at the same flow rate as actual blood, so that a learner can feel an injection reaction force while giving an injection to the apparatus. The skin pad and the arm model can be easily attached and detached to and from each other, in order to make the practice easy, to avoid liquid blood leakage, and to increase durability of the apparatus (i.e. its lifespan). Thus, learners can continuously use the arm model apparatus for practicing carrying out intravenous injection and taking blood.

<CIT> discloses another example of such medical devices. In particular, it refers to a phlebotomy training device which is adapted for attachment to a person's arm so that students can practice venipuncture techniques on a live subject. The device is formed as double-layered structure consisting of an artificial skin and a core. The artificial skin is formed of a latex material substantially covering the device. The core comprises a resilient, foam or sponge like material which simulates the puncture resistance of muscle and tissue in the forearm, wherein such material may comprise expanded PVC, plastics, rubber or cellulose. The core incorporates a network of channels wherein resilient tubing is placed to form artificial veins and arteries. The tubing must be capable of withstanding repeated punctures from conventional hypodermic needles while maintaining water tight integrity.

Document <CIT> discloses a simulated abdominal wall model for practicing laparoscopic first entry surgical techniques. The model includes a simulated abdominal wall portion captured between two frame elements of a support. The support is connectable to a surgical trainer. Therefore, it is observed in first place, that these devices are limited to the performance of very few specific medical techniques and procedures, and in many cases, basically related with simple clinical applications.

In addition, it should also be noted that the repeatability of performing the training prevails over other factors. More specifically, the layer configuration and the selection of materials focus on durability and reusability, therefore losing some realism.

The object of the present invention is a device for medical training as defined in independent claim <NUM> and which may be used for a wide range of medical techniques and procedures, especially in the surgical field, by means of a more realistic multi-layered structure on which functionality prevails over durability and reusability.

The object of the present invention is also a method of medical training associated with said device, as defined in independent claim <NUM>.

The device for medical training of the present invention comprises:.

Thus, the device is provided with a series of layers imitating the various tissues that can be found in the human anatomy. These layers are formed with materials that imitate in texture and touch the properties of their counterparts. Thus, a greater realism is obtained.

Preferably, the skin-simulating outer layer is made of an addition cure silicone rubber compound, having a feel an appearance similar to the ridged pattern of human skin.

Preferably, the skin-simulating outer layer has a thickness of from <NUM> to <NUM>, for an embodiment of the present invention in which the device imitates a human arm. Nonetheless, the thickness of the skin-simulating outer layer may be different (i.e. lower or higher) in other particular cases.

According to a preferred example, the composition of the skin-simulating outer layer comprises an addition cure silicone rubber compound having the following properties; Specific Gravity of <NUM>/cc (ASTM D-<NUM>), Specific Volume of <NUM> cu. (ASTM D-<NUM>), Shore Hardness of <NUM> A (ASTM D-<NUM>), Tensile Strength of <NUM> psi (ASTM D-<NUM>), Mixed Viscosity of <NUM> cps (ASTM D-<NUM>), Pot Life of <NUM> (ASTM D-<NUM>), Modulus <NUM> of <NUM> psi (ASTM D-<NUM>), Elongation at Break of <NUM>% (ASTM D-<NUM>), Shrinkage <<NUM> in. (ASTM D-<NUM>).

Preferably, the subcutaneous fat-simulating layer is made of an addition cure silicone rubber compound. It is preferably a yellow-coloured layer, arranged just below the skin-simulating outer layer, thus imitating the position of subcutaneous fat.

Preferably, the subcutaneous fat-simulating layer has a thickness of from <NUM> to <NUM>, for an embodiment of the present invention in which the device imitates a human arm. Nonetheless, the thickness of the subcutaneous fat-simulating layer may be different (i.e. lower or higher) when the device imitates other parts of the human anatomy.

According to a preferred example, the composition of the subcutaneous fat-simulating layer comprises an addition cure silicone rubber compound having the following properties; Specific Gravity of <NUM>/cc (ASTM D-<NUM>), Specific Volume of <NUM> cu. (ASTM D-<NUM>), Shore Hardness of <NUM> A (ASTM D-<NUM>), Tensile Strength of <NUM> psi (ASTM D-<NUM>), Mixed Viscosity of <NUM> cps (ASTM D-<NUM>), Pot Life of <NUM> (ASTM D-<NUM>), Modulus <NUM> of <NUM> psi (ASTM D-<NUM>), Elongation at Break of <NUM>% (ASTM D-<NUM>), Shrinkage <<NUM> in. (ASTM D-<NUM>).

Preferably, the fascia-simulating layer is made of a super-soft addition cure silicone rubber compound. The fascia-simulating layer is preferably a translucent layer.

The fascia-simulating layer increases the realism of performing the training of medical techniques and procedures, especially in the surgical field, as it contributes to simulate a more realistic behaviour of the blood-simulating liquid that may be contained in the device. In particular, it retains the blood-simulating liquid once it is released as a consequence of the training (for example; when cutting a blood vessel-simulating tube), thus creating flooding areas, or areas where the liquid is stagnated, as it would happen in actual practice.

Preferably, the fascia-simulating layer has a thickness of <NUM> to <NUM>, for an embodiment in which the device imitates a human arm. Nonetheless, the thickness of fascia-simulating layer may be different (i.e. lower or higher) when the device imitates other parts of the human anatomy.

According to a preferred example, the composition of the fascia-simulating layer comprises a super-soft addition cure silicone rubber compound having the following properties; Specific Gravity of <NUM>/cc (ASTM D-<NUM>), Specific Volume of <NUM> cu. (ASTM D-<NUM>), Shore Hardness of <NUM>-<NUM> A (ASTM D-<NUM>), Tensile Strength of <NUM> psi (ASTM D-<NUM>), Mixed Viscosity of <NUM> cps (ASTM D-<NUM>), Pot Life of <NUM> (ASTM D-<NUM>), Modulus <NUM> of <NUM> psi (ASTM D-<NUM>), Elongation at Break of <NUM>% (ASTM D-<NUM>), Shrinkage <<NUM> in. (ASTM D-<NUM>), Die B Tear Strength of <NUM> psi (ASTM D-<NUM>).

Preferably, the first muscle-simulating layer is made of flexible polyurethane foam. It is preferably a red-coloured layer, arranged just below the fascia-simulating layer.

Preferably, the first muscle-simulating layer has a thickness of <NUM> to <NUM>, for an embodiment in which the device imitates a human arm. Nonetheless, the thickness of the first muscle-simulating layer may be different (i.e. lower or higher) when the device imitates other parts of the human anatomy.

Preferably, the muscle-simulating layer is split by the fascia-simulating layer for a greater realism of the device. That is, defining a supra muscle-simulating layer and an infra muscle-simulating layer. Therefore, in addition to the first muscle-simulating layer, the device further comprises a second muscle-simulating layer located between the subcutaneous fat-simulating layer and the fascia-simulating layer.

Preferably, the second muscle-simulating layer is made of flexible polyurethane foam. It is preferably a red-coloured layer, arranged just above the fascia-simulating layer.

Preferably, the first muscle-simulating layer has a thickness of <NUM> to <NUM> and the second muscle-simulating layer has a thickness of from <NUM> to <NUM>, for an embodiment in which the device imitates a human arm. Nonetheless, the thickness of the first muscle-simulating layer and the second muscle-simulating layer may vary (i.e. being lower or higher) when the device imitates different anatomical regions.

According to a preferred example, the composition of the first muscle-simulating layer and/or the second muscle-simulating layer comprises a polyurethane foam having the following properties; <NUM> Times Volume Expansion, Specific Gravity of <NUM>/cc (ASTM D-<NUM>), Specific Volume of <NUM> cu. (ASTM D-<NUM>), Mixed Viscosity of <NUM> cps (ASTM D-<NUM>), Pot Life of <NUM> sec (ASTM D-<NUM>).

The previously mentioned flooding or stagnating effect of the fascia-simulating layer further increases the realism of performing the training of medical techniques and procedures, especially in the surgical field, in combination with the first muscle-simulating layer, or in combination with both the first muscle-simulating layer and the second muscle-simulating layer. This is due to the combination of the impermeable character of the fascia-simulating layer with the porous character of the muscle-simulating layers.

Blood vessel-simulating tubes may imitate any component of the circulatory system that transport blood through the human body, such as veins or arteries. Preferably, each blood vessel-simulating tube is made of a super-soft addition cure silicone rubber compound.

Preferably, a blood vessel-simulating tube which imitates a vein or artery of a human arm has a wall thickness of from <NUM> to <NUM>. More specifically, a wall thickness of <NUM> to <NUM> for a vein, and a wall thickness of <NUM> to <NUM> for an artery. Nonetheless, the wall thickness of the blood vessel-simulating tube may be different (i.e. lower or higher) when it imitates blood vessels of other parts of the human anatomy.

Preferably, a blood vessel-simulating tube which imitates a vein or artery of a human arm has an outer diameter of from <NUM> to <NUM>. Nonetheless, the outer diameter of the blood vessel-simulating tube may be different (i.e. lower or higher) when it imitates blood vessels of other parts of the human anatomy.

Preferably, a blood vessel-simulating tube which imitates a vein is made of a translucent blue-coloured tube, whereas a blood vessel-simulating tube which imitates an artery is made of a translucent red-coloured tube. Preferably, each blood vessel-simulating tube comprises:.

In this way, the blood vessel-simulating tube allows the flowing through it of a liquid injected through one of the ends, in order to imitate its physiological behaviour. The ends may be disposed at different places of the device, in an accessible manner, in order to allow creating vascular accesses at different points.

The blood vessel-simulating tubes may adopt any shape or form, such as Y-shaped, or follow any path, that may be found in the network of blood vessels of the circulatory system.

Preferably, for an embodiment which corresponds to a representation of the radial and humeral anatomy, together with its main vascular bed, the device comprises:.

The arrangement of crossing Y-shaped blood vessel-simulating tubes, following the distribution in the human body, allows performing the different approaches for creating arteriovenous fistulas. These fistulas can be both native (side-to-side or end-to-side) and prosthetic.

According to a preferred example, the composition of any blood vessel-simulating tube comprises a super-soft addition cure silicone rubber compound having the following properties; Specific Gravity of <NUM>/cc (ASTM D-<NUM>), Specific Volume of <NUM> cu. (ASTM D-<NUM>), Shore Hardness of <NUM>-<NUM> A (ASTM D-<NUM>), Tensile Strength of <NUM> psi (ASTM D-<NUM>), Mixed Viscosity of <NUM> cps (ASTM D-<NUM>), Pot Life of <NUM> (ASTM D-<NUM>), Modulus <NUM> of <NUM> psi (ASTM D-<NUM>), Elongation at Break of <NUM>% (ASTM D-<NUM>), Shrinkage <<NUM> in. (ASTM D-<NUM>), Die B Tear Strength of <NUM> psi (ASTM D-<NUM>).

The structure of the device may adopt different forms and shapes, either conforming a separated tool/apparatus to work on, or forming part of another object, such as a mannequin or artificial limb.

In any case, the device may comprise a support body, solid or rigid enough to ensure the proper placement and immobilisation of the same. The layers and tubes fit inside the support body, either being an integral part of the same (all the device is replaced once it is damaged), or as a consumable element/product that may be replaced by a new one, once the training has been completed, and/or the layers and/or tubes are considerably damaged.

According to a preferred example, the support body is made of rigid polyurethane resin, having the following properties; Shore Hardness D of <NUM>-<NUM>, Viscosity of <NUM>-<NUM> mPa. s, Density of <NUM>-<NUM>/cm3, Pot Life of <NUM> (ASTM D-<NUM>).

The device of the present invention is suitable for medical training in general, especially for surgical training, and more specifically for vascular anastomoses creation training or vascular access surgical treatment of complications training.

The present invention also refers to a method for medical training that it comprises using the device for medical training of the present invention, as described above.

Preferably, the method for medical training further comprises one or more of the following steps:.

Preferably, the method for medical training comprises the steps of:.

Preferably, the method for medical training further comprises the step of:
i) cutting the second muscle-simulating layer after the step c) and before the step d).

Preferably, the method for medical training further comprises the steps of:.

Therefore, the structure of the device makes it possible to reproduce the entire surgical procedure, including the cutting of the different layers, vessel resection, identification and ligation, as well as their clipping and subsequent aspiration of the excess fluid (otherwise it will remain in the cutting area, as occurs in clinical practice). Once these steps have been carried out, the vascular access itself would then be created, true to clinical life as a result of the reliable mechanical behaviour of the veins and arteries under tensile loading. Once the process has ended, the product allows practicing ligation and stitching of the various layers to close the surgical wound.

The present invention also refers to the use of the device of the present invention for medical training.

A series of drawings will be described below very briefly which will aid a better understanding of the invention and they expressly relate to two preferred embodiments of the same which are presented as a non-limiting examples thereof.

<FIG> refer to a first exemplary embodiment of the device (<NUM>) for medical treatment of the present invention, which imitates the radial and humeral anatomy of a human arm and its main vascular bed. This device (<NUM>) is especially designed for surgical training, and more specifically for vascular anastomoses creation training or vascular access surgical treatment of complications training.

As can be seen in <FIG>, the device (<NUM>) comprises:.

Therefore, according to the present exemplary embodiment, the fascia-simulating layer (<NUM>) is arranged just above the first muscle-simulating layer (<NUM>) and just below the second muscle-simulating layer (<NUM>).

The skin-simulating outer layer (<NUM>) is made of an addition cure silicone rubber compound, having a feel an appearance similar to the ridged pattern of human skin. The skin-simulating outer layer (<NUM>) has a thickness of from <NUM> to <NUM>.

The subcutaneous fat-simulating layer (<NUM>) is made of an addition cure silicone rubber compound. It is preferably a yellow-coloured layer, arranged just below the skin-simulating outer layer (<NUM>), thus imitating the position of subcutaneous fat. The subcutaneous fat-simulating layer (<NUM>) has a thickness of from <NUM> to <NUM>.

The fascia-simulating layer (<NUM>) is made of a super-soft addition cure silicone rubber compound. The fascia-simulating layer (<NUM>) is preferably a translucent layer. The fascia-simulating layer (<NUM>) has a thickness of <NUM> to <NUM>.

The first muscle-simulating layer (<NUM>) is made of flexible polyurethane foam. It is preferably a red-coloured layer, arranged just below the fascia-simulating layer (<NUM>). The first muscle-simulating layer (<NUM>) has a thickness of <NUM> to <NUM>.

The second muscle-simulating layer (<NUM>) is made of flexible polyurethane foam. It is preferably a red-coloured layer, arranged just above the fascia-simulating layer (<NUM>). The second muscle-simulating layer (<NUM>) has a thickness of from <NUM> to <NUM>.

The blood vessel-simulating tubes (<NUM>, 7a, 7v) in <FIG> are illustrated in hidden lines, as they are not externally visible. <FIG> also shows the blood vessel-simulating tubes (<NUM>, 7a, 7v) in hidden lines, as they are embedded in the first muscle-simulating layer (<NUM>).

Blood vessel-simulating tubes (<NUM>, 7a, 7v) are made of a super-soft addition cure silicone rubber compound. They have a wall thickness of from <NUM> to <NUM>, and an outer diameter of from <NUM> to <NUM>.

Each blood vessel-simulating tube (<NUM>, 7a, 7v) comprises:.

In this way, the blood vessel-simulating tubes (<NUM>, 7a, 7v) allow the flowing through them of a liquid injected through the ends (<NUM>, <NUM>), in order to imitate its physiological behaviour. The ends (<NUM>, <NUM>) may be disposed at different places of the device (<NUM>), in an accessible manner, in order to allow creating vascular accesses at different points.

The first Y-shaped blood vessel-simulating tube (7a) is made of a translucent blue-coloured tube, and it imitates an artery. It presents a deeper placement with respect to a second Y-shaped blood vessel-simulating tube (7v) in the central part of the device (<NUM>).

The second Y-shaped blood vessel-simulating tube (7v) is made of a translucent red-coloured tube, and it imitates a vein. It presents a more superficial placement with respect to the first Y-shaped blood vessel-simulating tube (7a) in the central part of the device (<NUM>).

The device (<NUM>) comprise a rectangular support body (<NUM>), solid or rigid enough to ensure the proper placement and immobilisation of the same, wherein the layers (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) and tubes (<NUM>, 7a, 7v) fit inside said support body (<NUM>).

The skin-simulating outer layer (<NUM>) extends perimetrically all around the device (<NUM>), defining a perimetrical extension (2e) configured to be fixed to the support body (<NUM>). In this case, the perimetrical extension (2e) is fixed upon the upper edge or border (8b) of the support body (<NUM>), but in other cases it may partially or totally wrap the support body (<NUM>).

The rest of the layers (<NUM>, <NUM>, <NUM>, <NUM>) are arranged within the support body (<NUM>) one on top of the other, being kept together in contact by the pressure exerted by the skin-simulating outer layer (<NUM>), which acts as a covering of all of them.

The present invention also refers to a method for medical training that it comprises using the device (<NUM>) for medical training of the present invention, according to the first exemplary embodiment.

The method for medical training further comprises one or more of the following steps:.

For vascular anastomoses creation training or vascular access surgical treatment of complications training the method for medical training comprises the steps of:.

The method for medical training further comprises the step of:
i) cutting the second muscle-simulating layer (<NUM>) after the step c) and before the step d).

The method for medical training further comprises the steps of:.

<FIG> refers to a second exemplary embodiment of the device (<NUM>) for medical treatment of the present invention, which imitates the radial and humeral anatomy of a human arm and its main vascular bed. This device (<NUM>) is especially designed for surgical training, and more specifically for vascular anastomoses creation training or vascular access surgical treatment of complications training.

As can be seen in <FIG>, in this case, the device (<NUM>) does not comprise the second muscle-simulating layer (<NUM>). So, the first muscle-simulating layer (<NUM>) has a thickness of <NUM> to <NUM>. The rest of the features are the same as those of the first embodiment.

The method for medical training described for the first exemplary embodiment may be also applied for the second exemplary embodiment without considering the steps that involve the second muscle-simulating layer (<NUM>), that is, without considering the step i).

Claim 1:
A device for medical training, comprising:
• a skin-simulating outer layer (<NUM>);
• a subcutaneous fat-simulating layer (<NUM>) located under the skin-simulating outer layer (<NUM>);
• a fascia-simulating layer (<NUM>) located under the subcutaneous fat-simulating layer (<NUM>); and
• a first muscle-simulating layer (<NUM>) located under the fascia-simulating layer (<NUM>);
said device (<NUM>) characterised in that the fascia-simulating layer (<NUM>) has an impermeable character; and in that said fascia-simulating layer (<NUM>) is made of a super-soft addition cure silicone rubber compound.