Apparatus for amplification of arterial and venous circulation of the limbs

Abstract

The invention concerns an apparatus (1 ) for amplification of the arterial and venous circulation of the limbs (3). The apparatus comprises an outer casing (2), configured to be wrapped around a limb (3) and the respective distal end, and connected to a fluid¬ dynamic system (4). The casing forms a closed, rigid and inextensible casing, and allows pressure changes produced by the fluid-dynamic system to be transmitted to the limb. The casing is openable for the insertion and removal of the limb to be treated and for maintenance, and comprises at least three compartments (20), substantially toroidal in shape, which together, variously bordering or overlapping, surround the entire surface of the limb to be treated. The fluid-dynamic system performs a pressure change within each of said compartments. The apparatus further comprises an electronic control system (12).

Description

[0001] APPARATUS FOR AMPLIFICATION OF ARTERIAL AND VENOUS CIRCULATION OF THE LIMBS

[0002] The present invention relates to an apparatus for amplification of arterial and venous circulation of the limbs.

[0003] Many diseases can lead to varying degrees of defects in arterial blood flow to the extremities of the limbs, most frequently to the lower limbs.

[0004] In cases involving the large arterial vessels, which is a very frequent occurrence, surgical therapies by means of unblocking and bypass construction can be used effectively.

[0005] In all other cases involving the small vessels, where a margin of surgical treatment is not possible or in cases where surgical therapy itself has failed, we have no methods that can mechanically improve the flow of arterial blood to the extremities of the limbs.

[0006] Likewise, many diseases can lead to varying degrees of defects in the venous micro- and macro-circulation in the return of non-oxygenated blood from the extremities to the heart.

[0007] The therapeutic devices that we can use, such as elastic stockings and pneumatic boots, have a solely compressive action and with random and long times very large sectors of the limb, increasing the pressure throughout the entire thickness of the treated area, squeezing the venous circulation, the interstitial flow and the arterial circulation with all their ramifications.

[0008] No devices are available that can mechanically aid selectively alternately and with synchronised timing the two circulations, the arterial inflow and the venous return, which have opposite directions and timing to each other.

[0009] In the not infrequent case that both extremity arterial inflow and venous outflow to the heart are adversely affected in the same limb, current medical science offers, in the first case, pharmacological instruments that dilate the vessels but worsen stasis and, in the second case, offers compressive instruments that constrict the vessels and vice versa obstruct the arterial circulation.

[0010] No device is available that can simultaneously treat the opposite circulatory needs.

[0011] A further, and not secondary, consideration of the state of the art in medical science concerns the almost exclusive existence of pharmacological therapy for the resuscitative treatment of the condition of severe hypotension, without being able to make use of non- invasive external aids that can be adjusted and are effective over time.

[0012] The task of the present invention is to provide an apparatus that overcomes the drawbacks of the aforementioned prior art.

[0013] In the context of this task, an aim of the invention is to provide an apparatus which can be applied to the outside of the lower or upper limb and which is capable of amplifying, in synchrony with the cardiac cycle, both the systolic volumetric inflow of arterial blood to the extremities of the limb and the diastolic volumetric outflow of venous blood in the opposite direction.

[0014] A particular aim of the invention is to provide an apparatus which, in the area of arterial circulation, is capable of at least partially achieving one or more of the following effects:

[0015] - vascularise and improve the chances of recovery of the ischaemic limb at risk of amputation without surgery;

[0016] - vascularise and improve healing of trophic lesions of the limbs;

[0017] - improve the painful symptomatology of the ischaemic limb;

[0018] - increase the walking range of the limb with vascularisation supported by collateral circulations with little overall compensation;

[0019] - promote the formation of stable and durable collateral circulations in cases of severe arterial vasculopathy of the lower or upper limbs.

[0020] Another particular aim of the invention is to provide an apparatus which, in the area of venous circulation, is capable of at least partially achieving one or more of the following effects:

[0021] - reducing oedema in the lower or upper limbs;

[0022] - reducing chronic lymphoedema;

[0023] - reducing sclerodystrophic panniculitis;

[0024] - reducing elephantiasis;

[0025] - improving the healing time of stasis ulcers.

[0026] Another particular aim of the invention is to create a device that, in the area of simultaneous arterial and venous circulation, is able to improve the healing of mixed ulcerative lesions in which arterial and venous pathologies coexist.

[0027] Another particular aim of the invention is to provide a device which, in the field of intensive care aids, is able to achieve at least partially one or more of the following effects:

[0028] - preventing venous thrombosis in bedridden or surgical patients;

[0029] - supporting resuscitative therapy in the management of hypotension;

[0030] - supporting resuscitative therapy to sustain the vascularisation of the important organs;

[0031] - aiding resuscitative therapy to counter hypovolemic damage. Another particular purpose of the invention is to provide a device which, in the field of rehabilitation therapy aids, is capable of at least partially achieving one or more of the following effects:

[0032] - improving functional recovery in muscle damage;

[0033] - improving recovery of functionality and efficiency following muscle stress in athletes;

[0034] - improve the state of muscle trophism and efficiency in athletes in the preparatory phase.

[0035] Another aim of the present invention is to provide an apparatus which, due to its special design features, is able to ensure the broadest guarantees of reliability and safety in use.

[0036] These aims, and others that will appear better later, are achieved by an apparatus for amplification of arterial and venous circulation of the limbs, as claimed in the appended claims.

[0037] The apparatus according to the invention acts by creating, upon arrival of systolic blood flow, a gradual and progressive wave of negative pressure from the proximal region of the limb to the extremities of the limb.

[0038] The depressor wave with centrifugal suction precedes the systolic arterial blood flow wave by progressively decreasing the resistance to its flow to the most peripheral branches of the fingers. The system is thus designed in such a way that the vascular bed that is about to be supplied presents the least possible resistance in order to suck in the incoming systolic wave.

[0039] In fact, the apparatus is configured so that the depressor wave ideally prepares the decrease in resistance within the vessels for the imminent blood flow in the systolic phase.

[0040] Synchronisation can take place automatically, by electronically calculating, with the aid of numerous sensors, all specific and individual factors such as inertia time, tissue transmission time and parietal elasticity status.

[0041] In the opposite direction, the system creates a centripetal positive propulsive wave that propels the blood and lymph flow from the fingers to the proximal area of the limb covered by the device itself towards the heart.

[0042] The two actions, each in the opposite direction to the other, take place in the time of a complete systolic-diastolic cardiac cycle of one heartbeat, e.g. in the case of a heart rate of 60 beats per minute, the device performs the complete cycle, including the depressive suction phase and the propulsive compression phase in the time of a one-second heartbeat, and thus in 60 seconds creates 60 depressor wave cycles and 60 positive pressure cycles.

[0043] The invention concerns an apparatus for amplification of the arterial and venous circulation of the limbs. The apparatus comprises an outer casing, configured to be wrapped around a limb and its distal end, and connected to a fluid-dynamic system. The casing forms a closed, rigid and inextensible casing, and allows the transmission of pressure variations produced by said fluid-dynamic system to said limb. The casing can be opened for the insertion and removal of the limb to be treated and for maintenance. The casing comprises at least three compartments, essentially toroidal in shape, which together, variously adjoining or overlapping, surround the entire surface of the limb to be treated. The fluid-dynamic system performs a pressure change within each of said compartments. The apparatus further comprises an electronic control system.

[0044] The special design of the apparatus makes it possible to effectively amplify the arterial and venous circulation in a limb and its distal extremity (hand or foot), particularly in the fingers that are often subject to venous insufficiency.

[0045] Advantageously, the fluid-dynamic system is configured to achieve a specific pressure variation within each compartment, independent of the pressure variations of the other compartments.

[0046] This solution makes it easy to define the pressure and depression waves to be applied to the limb.

[0047] Preferably the space between the casing and the limb is connected to a suction actuator.

[0048] This solution allows for faster and more precise application of the depression within each compartment.

[0049] Preferably, each of the compartments is surrounded on three sides by rigid, inextensible material, including the lateral part bordering the adjacent compartment, and excluding the part in contact with the skin of the limb, which is made of extensible material.

[0050] In this way, pressure variations within each compartment are applied directly and solely to the limb, improving speed and accuracy.

[0051] Preferably the apparatus of the invention further comprises one or more sensors configured to detect: temperature, pressure, flow, ECG, Po2.

[0052] The presence of the sensors allows real-time monitoring of the operation of the apparatus as well as the state of health of the patient and the limb.

[0053] Preferably, the electronic control system is configured to control the fluid-dynamic system on the basis of one or more of:

[0054] - a preloaded logic; and / or

[0055] - specific parameters; and / or

[0056] - data collected instantaneously by the sensors. In this way, the electronic control system can better manage the application of pressure and depression waves and, if necessary, update the apparatus’s operating parameters in real time.

[0057] Advantageously, the fluid-dynamic system comprises an actuation control unit connected to a compression actuator and a suction actuator.

[0058] The actuation control unit operates according to the control signals generated by the electronic control system.

[0059] Preferably, each compartment comprises a chamber made of a waterproof and extensible material connected to the fluid-dynamic system’s actuation control unit.

[0060] The provision of an extensible chamber within each rigid compartment allows for particularly effective and efficient operation.

[0061] In some embodiments, the chamber comprises a pocket within it, and the chamber is connected to a circuit for supplying a liquid, while the pocket is connected to the actuation control unit.

[0062] This solution makes it possible to exploit both the immediate propagation of pressure within a liquid (inside the chamber) and the ease of handling a small amount of gas (inside the pocket).

[0063] Preferably the chamber includes an elastic outer jacket.

[0064] The elasticity of the jacket helps the compression of the chamber itself during suction.

[0065] Advantageously, the apparatus further comprises a gasket configured to guarantee the fluid tightness, so as to seal the space comprised between the casing and the limb.

[0066] The presence of the gasket helps to maintain a constant depression in the space between the casing and the limb.

[0067] Preferably the casing is made at least partially of transparent material.

[0068] The presence of at least one transparent portion in the casing makes it easier to keep track of the state of the limb, both visually and through diagnostic tools.

[0069] In some embodiments, the suction actuator comprises a device, based on a Venturi valve, configured to achieve the desired depression by exploiting the energy of the compressed air provided by the compression actuator.

[0070] This solution avoids the need for an external suction line (commonly known as a vacuum).

[0071] In some embodiments, the compression actuator and the suction actuator are integrated into a single device comprising a cylindrical chamber along which a piston can slide, which can alternately perform a compression stroke or a suction stroke. Preferably the casing defines at least five compartments.

[0072] The applicant’s studies have shown that, in order to achieve the desired results, the minimum number of compartments is three, and that it is preferable to have at least five.

[0073] In some embodiments, the apparatus comprises a fluid-dynamic system, an electronic control system and a plurality of casings, each configured to be wrapped around a limb and its distal end.

[0074] These embodiments not only treat the limbs enclosed in the respective casings, but also have an effect on the entire circulatory system and the heart itself.

[0075] Further characteristics and advantages will result from the description of preferred, but not exclusive, embodiments of the invention, illustrated by way of non-limiting example in the accompanying drawings, in which:

[0076] Figure 1 is a schematic perspective view of the apparatus according to the invention;

[0077] Figure 2 is a sectional schematic view of the apparatus in Figure 1 ;

[0078] Figure 3 is a schematic perspective view of the apparatus according to a further aspect of the invention;

[0079] Figure 4 is a sectional schematic view of the apparatus in Figure 3, shown in the suction phase;

[0080] Figure 5 is a sectional schematic view of the apparatus in Figure 3, illustrated in the compression phase;

[0081] Figure 6 is a schematic perspective view of the apparatus according to a further aspect of the invention;

[0082] Figure 7 is a sectional schematic view of the apparatus in Figure 6, illustrated in the compression phase;

[0083] Figure 8 is a sectional schematic view of the apparatus in Figure 6, shown in the suction phase;

[0084] Figure 9 is a schematic view of the apparatus according to the invention in a preliminary phase of application to a patient’s limb;

[0085] Figure 10 is a partially sectional schematic view of the detail of the proximal end of the apparatus according to the invention applied to a patient’s limb;

[0086] Figure 11 is a sectional schematic view of an embodiment of the invention applied to a patient’s limb;

[0087] Figure 12 is a view, similar to that in Figure 11 , of a different embodiment of the invention; Figure 13 is a schematic view of the section taken along the line XIII-XIII in Figure 11 or 12;

[0088] Figure 14 is a schematic view of a chamber used in the embodiments of the invention similar to that in Figure 11 ; and

[0089] Figure 15 is a schematic view of the section taken along the line XV-XV in Figure 14.

[0090] Some conventions commonly adopted in medical and anatomical fields are adopted in this discussion. In particular, the term “proximal” indicates a position relatively close to the centre of the body, while the term “distal” indicates a relatively peripheral position, i.e. further away from the centre of the body.

[0091] In the present discussion, pressure variations, positive and / or negative, are considered with respect to atmospheric pressure (760 mmHg). In particular, a “positive pressure” is a pressure greater than atmospheric pressure; for example, a (relative) pressure of 30 mmHg is a pressure that exceeds atmospheric pressure by 30 mmHg, i.e. an absolute pressure of 790 mmHg. Similarly, a “negative pressure” or depression is a pressure lower than atmospheric pressure; for example, a (relative) pressure of -10 mmHg is a pressure 10 mmHg lower than atmospheric pressure, i.e. an absolute pressure of 750 mmHg.

[0092] With reference to the above-mentioned figures, the apparatus according to the invention, referred to as a whole by reference number 1 , comprises an outer body or casing 2, for example in the form of a boot, adapted to be wrapped around a limb 3, in this case a leg, and connected to an external pneumatic / hydraulic or fluid-dynamic system 4 via piping 5.

[0093] The casing 2 is a closed, rigid and inextensible casing, and allows pressure variations produced by the fluid-dynamic system 4 to be transmitted quickly and accurately to the limb 3.

[0094] In accordance with the invention, the casing 2 is configured to enclose the limb 3 and the respective distal end, i.e. to also enclose the foot or hand within it.

[0095] The casing 2 can be opened for the insertion and removal of the limb 3 to be treated and for maintenance, and can also be closed again, in a sealed manner, by means of special gaskets.

[0096] By way of example, Figure 9 shows a casing 2, in the form of a boot, is book-like opened for the insertion of the limb 3 to be treated (in this case a leg). In accordance with this embodiment, the casing 2 is cut in two along a sagittal plane to form two lateral halfcasings, hinged together.

[0097] In accordance with other embodiments (not shown), the casing 2 can take on different shapes, e.g. the casing 2 can be cut in two along a frontal plane to form a front half-casing and a rear half-casing, similar to some so-called “rear-entry” ski boots. The closure of the two half-casings can be achieved, in a manner known in itself, by means of lever hooks, spring hooks, laces or the like, which bind their relative position to form the casing 2. Preferably, a suitable gasket is placed along the line of contact between the two half-casings to guarantee the fluid tightness of the closed casing 2.

[0098] Figure 9 also shows that the casing 2 comprises a plurality of windows 26 made of transparent material. The presence of the windows 26 makes it possible to keep the limb 3 under control, both visually and by means of diagnostic tools such as echo-Doppler or the like. Alternatively, the entire casing 2 can be made of transparent material.

[0099] The hermetic closure of the system on the opposite side to the extremity of the limb 3 is achieved by means of a gasket 30 applied circularly and gently to the skin.

[0100] Figure 10 shows, in a partially sectional schematic detailed view, an example of the gasket 30. In accordance with this embodiment, the gasket 30 comprises a spongy, waterproof bandage 31. In order not to interfere with the blood circulation in the limb 3, the bandage 31 must be applied without compressing the limb 3 itself. The bandage 3 has an adequate thickness to fill the gap at the proximal end of the casing 2 between the latter and the limb 3. Preferably, the gasket 30 further comprises an additional swathe 32 applied to the limb 3 in a position immediately proximal to the bandage 31 . Then, one or more closing flaps 33 extend from the swathe 32, configured to be constrained to the outer surface of the casing 2 so as to constrain its position with respect to the limb 3. Finally, as can be seen in Figure 10, the bandage 31 is placed immediately proximal to the most proximal chamber 25.

[0101] The gasket 30 as a whole is configured to guarantee the fluid tightness, so as to seal the space 24 comprised between the casing 2 and the limb 3.

[0102] According to the present invention, the casing 2 comprises a plurality of compartments 20, substantially toroidal in shape, of various diameters, which surround, as a whole, variously adjoining or overlapping, the entire surface of the limb 3 to be treated. The casing 2 comprises at least three compartments 20, preferably at least six compartments 20.

[0103] Each compartment 20 is connected to the piping 5 via respective branch pipes 51 in such a way as to allow a pressure variation within each compartment 20 through the action of the fluid-dynamic system 4. Some possible configurations of the piping 5 will be described in more detail below.

[0104] The fluid-dynamic system 4 is configured to obtain within each compartment 20 a specific pressure variation, independent of the pressure variations of the other compartments 20.

[0105] Each compartment 20 can be surrounded by rigid, inextensible material on three sides, i.e. also in the lateral part bordering the adjacent compartment 20, excluding the part in contact with the skin of the limb, which is made of extensible material.

[0106] Advantageously, the entire toroid-shaped compartment not in contact with the skin is rigid and inextensible.

[0107] This construction method is designed so that all positive or negative pressure variations created within the compartment are discharged only and directly towards the limb and there is no leakage even to adjacent compartments.

[0108] By way of example, Figure 13 schematically shows a partial longitudinal section of the casing 2 applied to a limb 3. As can be seen, the casing 2 comprises an outer rigid shell and partial bulkheads extending inwards from the outer shell towards the limb 3. The bulkheads are configured in such a way as to laterally confine the chambers 25; thus each chamber 25 can only expand or contract in the direction of the limb 3. In addition, the bulkheads keep the chambers 25 in the correct position, even when they are empty and could easily move undesirably within the casing 2.

[0109] Advantageously, the outer wall of each chamber 25 assumes a suitable shape to best fill the internal volume of the relative compartment 20.

[0110] Preferably two adjacent chambers 25 are configured to overlap at least partially in the space between the limb 3 and the bulkhead separating them. A possible form of such an overlap is shown schematically in Figure 13.

[0111] The most distal compartment 20 is intended to accommodate the extremity of the limb 3, i.e. the hand or the foot; preferably this compartment 20 is not toroidal in shape, but being the last one it is also closed in the distal direction by a rigid wall; in this regard, see Figures 1 , 3, 6 and 9. In accordance with some embodiments, the chamber 25 housed in the most distal compartment 20 is configured to be individually wrapped around the fingers or toes. By way of example, the inner wall of the chamber 25, the one intended to come into contact with the patient’s skin, may comprise a glove or stocking shaped to accommodate each finger or toe separately. In this way, the pressure / depression waves applied by the apparatus 1 are transmitted directly to each individual finger or toe, thus amplifying the microcirculation in each of them. Conversely, the outer wall of the most distal chamber 25 may take on a shape similar to that of the other, more proximal chambers 25, i.e. a shape suited to best fill the internal volume of the relative compartment 20.

[0112] An electronic control system 12 regulates and controls the operation of the apparatus, ensuring its operation and safety.

[0113] The electronic control system 12 is designed to achieve optimal adjustment of the synchronisation of the various actions of the different compartments in consideration of the inertial times of transmission of the actions to the limb tissues, pressures, safety of the implant, data storage and verification of the effectiveness of the treatment in place. The electronic control system 12 comprises the necessary components such as sensors 8, actuators, solenoid valves, electronic boards, connections, monitors, memories, etc.

[0114] Advantageously, the apparatus comprises a layer of lightweight fabric in direct contact with the skin for protective purposes.

[0115] Advantageously, the outer casing 2 of each compartment 20 is made of a rigid, non- collapsible material so that positive and negative pressures can only be directed towards the tissues of the limb 3 contained therein.

[0116] The casing 2 consists of two hermetically closable parts for easy insertion and removal of the limb 3.

[0117] In the proximal part, where the device ends, an inextensible plastic ring with a soft gasket 30 that can be attached to the skin with Velcro or a plaster is provided to ensure that the internal system is completely airtight, in order to adapt to the different limb sizes of patients.

[0118] The apparatus 1 comprises a variable number of compartments 20, with fluid and / or pneumatic content. Preferably each casing 2 comprises a number of compartments 20 greater than three, even more preferably greater than five. Although a large number of compartments 20 per casing 2 is preferable for greater actuation accuracy, the increasing complexity of the system as the number of compartments 20 increases suggests keeping the number within a dozen.

[0119] The apparatus can use fluids, either liquids or gases, or both at the same time.

[0120] The fluid-dynamic system 4 generates the necessary positive and negative pressure variations either directly or via one or more pipes. For this purpose, the fluid-dynamic system 4 comprises an actuation unit 40 connected to a compression actuator 41 and a suction actuator 42. The compression actuator 41 is configured to make pressure greater than atmospheric pressure available, typically by means of compressed air. For example, the compression actuator 41 can make available a pressure of about 30 mmHg (4 kPa) above atmospheric pressure. The suction actuator 42 is configured to make a depression available, i.e. a pressure lower than atmospheric pressure. For example, the suction actuator 42 can make available a pressure of about 5 mmHg (666 Pa) below atmospheric pressure. The actuation unit 40 is configured to generate, in each individual compartment 20, a precise pressure curve (with values higher and lower than atmospheric pressure), in accordance with the signal provided by the electronic control system 12.

[0121] Preferably, the outer rigid casing 2 defines a plurality of compartments 20 side by side along the longitudinal axis of the limb 3. Each compartment 20 comprises an elastic and deformable chamber 25, which will be described in more detail below. The chambers 25 are therefore placed side by side within the space 24 between the casing 2 and the limb 3. Preferably, the inside of the space 24 is connected to the suction actuator 42 in such a way that, in use, it maintains a depression, i.e. a pressure below atmospheric pressure. For example, the pressure maintained in use within the space 24 may be about 10 mmHg (1.3 kPa) lower than atmospheric pressure. The chambers 25 are thus contained within the space 24 and are therefore subject to the depression that is maintained within it. Each of the chambers 25 is individually connected to the actuation unit 40 of the external fluiddynamic system 4.

[0122] In accordance with some embodiments, the suction actuator 42 comprises a device based on a Venturi valve, configured to achieve the desired depression by exploiting the compressed air energy provided by the compression actuator 41. In other words, according to some embodiments, the apparatus 1 of the invention can be fed by a single system supplying compressed air and through this obtain both the desired pressure and depression.

[0123] In accordance with some embodiments (see for example Figures 4 to 8), the compression actuator 41 and the suction actuator 42 are integrated in a single device comprising a cylindrical chamber along which a piston 6 can slide. In particular, a neutral position is defined for the piston, whereby a pressure equal to atmospheric pressure is established inside the cylindrical chamber. From the neutral position, under the action of a linear actuator 7, the piston 6 can perform a compression stroke, whereby it establishes a pressure in the cylindrical chamber that is greater than atmospheric pressure. Furthermore, from the neutral position, under the action of the linear actuator 7, the piston 6 can perform a suction stroke (opposite to the compression stroke), whereby it establishes a lower pressure in the cylindrical chamber than atmospheric pressure.

[0124] Regardless of the specific architecture of the system, the fluid-dynamic system 4 is configured to alternately control the gas pressure / depression to control the pressure within the chambers 25.

[0125] Figures 14 and 15 schematically show a possible embodiment of a chamber 25 for the apparatus 1 of the invention. In accordance with this embodiment, the chamber is made of a waterproof, stretchable material that can swell under the effect of the internal pressure. At the ends of the chamber 25 there are fastening means configured to be able to close the chamber 25 in a ring around the limb 3. The fastening means may comprise, for example, adhesive portions, laces or Velcro, similar to the cuff of a sphygmomanometer. In the particular embodiment of Figures 14 and 15, the chamber 25 comprises a pocket 22 within it. In this case, the chamber 25 is intended to be filled with liquid, typically water. Two openings, both equipped with a tap 55, are provided for this purpose, connecting the inside of the chamber 25 with a liquid supply circuit 54. When the chamber 25 is being filled, one opening acts as an inlet and the other acts as an outlet for the liquid. In this way, by circulating the liquid between the inlet and the outlet, it is possible to remove any air bubbles that may be present inside the chamber 25. Once all the air has been removed, the two taps 55 should be closed, so that the volume of liquid inside the chamber 25 is isolated from the supply circuit 54. Preferably, the chamber 25 also comprises means for controlling the temperature of the liquid inside it.

[0126] As mentioned, inside the chamber 25 a pocket 22 is arranged, designed to be supplied with gas, typically air. For this purpose, an opening is provided that connects the inside of the pocket 22 with the actuation unit 40 of the fluid-dynamic system 4.

[0127] Preferably, the chamber 25 comprises an elastic outer jacket 27 which, during the phase of decreasing the pressure inside the chamber 25, aids the expulsion of fluid inside the chamber 25 and thus the reduction of volume. In particular, in the case where the chamber 25 directly contains the gas, the elastic outer jacket 27 aids the expulsion of the gas from the chamber 25. On the other hand, in the case where the chamber 25 contains a liquid and comprises the inner pocket 22 containing the gas, the elastic outer jacket 27 presses down on the liquid in the chamber 25 and thus aids the expulsion of the gas from the pocket 22.

[0128] Preferably the outer jacket 27 of the chamber 25 is also configured to have as low a coefficient of friction as possible.

[0129] A chamber 25 similar to the one in Figure 14 is shown schematically in Figure 11 , closed in a ring around the limb 3 and enclosed within the casing 2.

[0130] As will be described in more detail below with reference to Figures 4 and 5, this embodiment in which the chamber 25 contains a fixed amount of liquid and the pocket 22 transmits variations in pressure is extremely advantageous.

[0131] Figure 12 schematically shows a different type of chamber 25 without the presence of the liquid. In this case, therefore, the chamber 25 comprises neither the pocket 22 nor the connection to the liquid supply circuit 54. The chamber 25 in Figure 12 is thus intended to be supplied with gas, typically air. For this purpose, an opening is provided that connects the inside of the chamber 25 directly with the actuation unit 40 of the fluiddynamic system 4.

[0132] The fluid-dynamic system 4, by means of the electronic control system 12, makes it possible to obtain in each compartment 20 the optimal values of pressure and depression intensity and duration, in the best sequence in relation to the chosen therapeutic purpose.

[0133] This electronic co-ordination takes place via multiple sensors of various types, solenoid valves and special hardware and software.

[0134] Preferably the apparatus 1 of the invention comprises:

[0135] - at least one temperature sensor 81 ; - at least one pressure sensor 82;

[0136] - at least one blood oxygenation (Po2) sensor 83.

[0137] Other useful sensors may be flow sensors, ECG, Doppler, etc., which are known in themselves.

[0138] Preferably each compartment 20 comprises one sensor of each type. Some sensors, typically temperature sensors 81 and / or pressure sensors 82, can be placed in the fluiddynamic system 4, e.g. along the piping 5 (Figure 2) to check the correct operating state thereof. In other cases, as shown schematically in Figures 11 and 12, the sensors 8 can be placed on the inner wall of the chamber 25, in contact with the skin of the limb 3, to monitor its physiological parameters.

[0139] Preferably, the apparatus 1 comprises one or more flow sensors configured to detect the flow of blood in the main arteries of the limb 3; advantageously, such flow sensors are positioned close to the proximal end of the casing 2. These sensors allow the electronic control system 12 to trigger the onset of the depression wave (suction action) by precisely synchronising it with the incoming systolic pressure wave in the arteries, despite the delay compared to the actual contraction of the ventricle.

[0140] Preferably, the apparatus 1 comprises an echocardiographic probe intended to be placed on the patient’s hemithorax and configured to monitor their right heart. This echocardiographic probe allows the blood flow rate of the incoming venous outflow to the heart to be monitored and regulated in real time. In particular, the signal provided by the echocardiographic probe makes it possible to adjust the pressure wave generated by the apparatus 1 in such a way as to push into the venous circulation a blood flow rate that is adequate for the patient’s right heart, i.e. a flow rate that can be received and managed by the right heart without disrupting its operation.

[0141] Figures 1 and 2 illustrate a first embodiment of the invention comprising.

[0142] As described above, the apparatus 1 comprises one or more pouch-like compartments 20 in the shape of a hollow (toroidal) cylinder completely enveloping the limb 3.

[0143] The compartment 20 can be a closed or open cylinder to facilitate limb insertion.

[0144] The compartment 20 has a gaseous content and is operated by the pressure change of the air contained therein.

[0145] The depression within the device, and thus the suction effect on the limb segment to be treated, occurs due to the formation of negative pressure within the compartment enveloping the limb, and may or may not rely on an additional vacuum, generated by special compressors, kept constant by means of a tank 10, within the entire rigid container and cavities (boot or gauntlet). The apparatus comprises a compression actuator 41 , connected to an air-content chamber 25 via compression pipes 52, and a suction actuator 42, connected to the chamber 25 via suction pipes 53.

[0146] The pneumatic circuit comprises the vacuum compensation tank 10.

[0147] The apparatus comprises a series of sensors 8 to control its operation.

[0148] Figures 3-5 illustrate an apparatus according to a further embodiment of the invention, referred to as a whole by reference numeral 1 , comprising a casing 2 formed by a plurality of compartments 20, each of which comprises a hermetically sealed, toroidal-shaped, liquid-containing chamber 25 in contact with the limb 3, completely enveloping it.

[0149] Inside the chamber 25, immersed in the liquid, is an internal expandable pocket 22, containing air, connected via a pipe 52 to a fluid-dynamic system 4.

[0150] This embodiment of the invention, of the fluid-pneumatic type, exploits the benefits of the rapid and homogeneous extension of positive and negative pressures over the entire limb, even with low force values, inherent in the properties of liquids, and exploits the benefits of the characteristics of gases, i.e. elasticity and transmission speed.

[0151] In fact, according to Pascal’s law, even a modest pressure variation applied to a small surface area of a liquid is evenly distributed over a much larger surface area, such as that of the entire limb.

[0152] In the present case, even a small amount of pressure / depression applied to the air contained in the inner pocket 22 is capable of uniformly and rapidly transmitting the pressure / depression to the entire fluid in the chamber 25, and thus to the biological contents of the limb enveloped in it.

[0153] The ideal application of this embodiment of the apparatus is in distal arterial diseases, in which the suction and compression phases must be applied on a suffering limb and skin, where the safety, precision and complete control of the sequence of processes must be at the highest possible level.

[0154] The fluid-dynamic system 4 generates positive or negative pressure, and the whole system is regulated in terms of timing, pressure intensity, sequences and safety by means of an electronic control system 12 that makes use of numerous sensors 8 of various kinds, such as pressure, temperature, flow, ECG, Doppler, Po2, etc.

[0155] Preferably, to achieve the best end result with the associated functional and clinical benefits, the transmission of pressure changes to the limb occurs in a very specific way, in this fluid-pneumatic system.

[0156] The pressures must be distributed evenly and equally over the entire surface of the limb; the system acts according to Pascal’s law by obtaining the homogeneous and equal distribution of a force applied to a liquid over the entire surface of its container.

[0157] Pressures / depressions must be able to be transmitted to the various types of tissue in the limb as quickly as possible.

[0158] The system utilises the transmission speed of the incompressibility of the liquids within the boot and uses the increased speed of gas passage through pipes of limited cross- sectional area.

[0159] The speed at which the pressures are transmitted to the limb is also determined by the low movement of pressure that the compressor system has to perform.

[0160] In fact, again according to Pascal’s law, the amount of force required to move the pressures on the limb is low, as a small force on a small surface area of liquid is sufficient to distribute the same force over a much larger surface area.

[0161] The pressures on the limb must be perfectly controllable and effective; the incompressibility of the liquid ensures a high correspondence between sensors and desired action.

[0162] The pressures must be maintained on the surface of the limb for the desired time with controlled precision. The system is fluid-dynamic with liquid content and only a minimal gaseous component and therefore the physical stability characteristics of liquids prevail by far.

[0163] The pressures must be able to be transmitted to the limb in the desired gradual and elastic manner. The minimal gaseous component allows for a gradual and elastic impact of forces on the limb, with the intensity that can be modified according to the volume of the air pocket contained in the chamber with liquid content.

[0164] The lower pressure required by the fluid-pneumatic system allows the system to drastically reduce the size and power of the compressors, making them more manageable, stable and durable.

[0165] The fluid-pneumatic system allows the use of a single pipe connection to the compressors.

[0166] The presence of liquid in direct contact with the limb allows the transmission of thermal energy to it by raising or lowering the temperature of the liquid itself.

[0167] The cylinder-shaped chamber 25 has an inner cylindrical foramen 23 and is made of a rigid material and is hermetically sealed even in the parts bordering the other chambers 25, while in the part in contact with the limb it is extensible and elastic.

[0168] The size of the pouch must be such that it can be interposed between the rigid inner surface of the apparatus boot casing and the limb to be treated, so as to envelop it completely with light contact.

[0169] This pouch contains liquid occupying the entire space between the outer shell and the limb to be treated.

[0170] The amount of fluid is adjusted at the beginning of the treatment according to the volume of the limb.

[0171] Figure 4 shows the apparatus 1 in the suction phase, while Figure 5 illustrates the compression phase.

[0172] Figures 6-8 illustrate an apparatus according to a further embodiment of the invention, referred to as a whole by reference numeral 1 , comprising a fluid-pneumatic type system comprising a series of compartments 20 defining an outer casing 2, for example in the form of a boot, adapted to be wrapped around a limb.

[0173] Each compartment 20 comprises a fluid-dynamic system 4 consisting of a pneumatic cylinder 6 operated by an actuator 7.

[0174] The pneumatic cylinder 6 feeds an inner expandable pocket 22 containing air, which acts in the inner chamber 25 of the compartment 20.

[0175] The apparatus 1 comprises 8 sensors, similar to the apparatus described above.

[0176] The operation of the apparatus 1 is essentially similar to the operation of the apparatus 1 described above.

[0177] The operation of the apparatus 1 of the invention is briefly described below, with reference to a single limb 3. Naturally, as a person skilled in the art can clearly understand, the simultaneous application of the invention to several limbs 3 of the same patient does not imply any substantial difference.

[0178] The electronic control system 12 is configured to define the pressure / depression application curves within the casing 2, one compartment 20 after the other. For this purpose, the electronic control system 12 is based on:

[0179] - a pre-loaded logic defining the typical operating methods of the invention; and / or

[0180] - specific parameters entered each time, e.g. relating to the condition of the specific limb 3 to be treated; and / or

[0181] - the data collected instantaneously by the sensors 8, data that allow the process to be monitored and / or adjusted.

[0182] The general purpose of the apparatus 1 is to generate along the limb 3, in each heartbeat (i.e. in each individual systolic-diastolic cardiac cycle) a first depression wave in the distal direction and a second pressure wave in the proximal direction. The depression wave must propagate along the limb 3 anticipating the propagation in the arteries of the pressure resulting from systole. The depression wave must therefore propagate in a distal direction, achieving the effect of actively sucking blood as far as and including the fingers / toes. On the contrary, the pressure wave must propagate along the limb 3 pushing blood through the veins towards the heart, taking advantage of the lack of back pressure resulting from the diastole. The pressure wave must therefore propagate in a proximal direction, achieving the effect of actively pushing the blood from the fingers / toes, included, along the entire limb.

[0183] In particular, therefore, once the apparatus 1 is correctly applied to the patient and is fully operational, a condition is established in which suction is applied within the space 24 comprised between the casing 2 and the limb 3, while the pressure within the chambers 25 compensates for the partial vacuum, so that a pressure equal to atmospheric pressure is maintained on the limb 3. From this situation, the electronic control system 12 commands the actuation unit 40 to generate and apply the depression wave. Specifically, the work cycle begins by reducing the pressure in the most proximal compartment 20; then, while the initial pressure in the most proximal compartment 20 is re-established, the pressure is reduced in the adjacent, immediately more distal compartment 20. The cycle continues until the most distal compartment 20 (the one enclosing the fingers / toes) is reached. Subsequently, the work cycle proceeds by increasing the pressure in the most distal compartment 20; then, while the initial pressure is re-established in the most distal compartment 20, the pressure is increased in the adjacent, immediately more proximal compartment 20. The cycle continues until the most proximal compartment 20 is reached (the first one that was actuated at the beginning of the cycle).

[0184] As can be clearly understood, each complete cycle (depression wave and pressure wave) must occur within the time of a single heartbeat. This means that considering an average heart rate of 60 bpm, each complete cycle should last 1 second.

[0185] If the casing 2 comprises five compartments 20, as each compartment is actuated twice in each cycle (once under depression, once under pressure), each pressure / depression pulse lasts on average 1 / 1 Oth of a second. Of course, this duration can also be shorter, e.g. 1 / 20th of a second with ten compartments 20.

[0186] In light of these trivial considerations, the importance of the particular structure of the apparatus 1 of the invention is particularly clear. In fact, many solutions have been adopted to enable effective pressure wave generation with similar actuation times. In particular, the solution in which the chamber 25 is filled with liquid and the pressure change is controlled via the air in the pocket 22 is particularly quick. This takes advantage of the speed and transfer of a small amount of air and the immediate transmission of pressure within the liquid. Again, the presence of the partial vacuum in the space 24 and the presence of the elastic jacket of the chambers 25 help the almost immediate propagation of the depression controlled by the actuation unit 40 throughout the compartment 20.

[0187] All the embodiments described above are interchangeable with each other and effective.

[0188] Each compartment can be constructed in several modes and variants with features that enhance different functions so that more technical options are available depending on the disease and person treated.

[0189] The different application and pressure transmission modes in the variants described can also co-exist in the same device and be interchangeable and easily replaced with each other depending on clinical needs or the data received from the system’s sensors.

[0190] In the embodiments illustrated here, the apparatus has been described in its application to both legs of the patient, however the apparatus, depending on the specific clinical need, can be applied to all upper and lower limbs in their segments and in particular:

[0191] - only one leg or both legs at the same time;

[0192] - the entire lower limb from the foot to the entire thigh or the entire upper limb from the hand to the shoulder;

[0193] - simultaneously with the four limbs, limited to the distal segments (legs and forearms);

[0194] - extensively and completely to the eight segments (two legs, two thighs, two forearms and two arms).

[0195] In practice, it has been found that the invention achieves its intended task and purpose by creating an apparatus operating by means of mechanical and electromechanical stimuli, to be positioned on the outside of the lower or upper limb, capable of amplifying, in a manner synchronised with the cardiac cycle, both the systolic volumetric inflow of arterial blood to the extremities of the limb and the diastolic volumetric outflow of venous blood in the opposite direction.

[0196] The apparatus according to the invention makes it possible to rapidly vary the overall pressure of the treated limb by creating sequential positive and negative pressures from the outside.

[0197] The apparatus according to the invention is susceptible of numerous modifications and variations, all of which are within the scope of the inventive concept; moreover, all the details may be replaced by technically equivalent elements.

[0198] Naturally, the materials used, as well as the dimensions, may be any according to the requirements and the state of the art.

Claims

CLAIMS1. Apparatus (1 ) for amplification of the arterial and venous circulation of the limbs (3), comprising an outer casing (2), configured to enclose a limb (3) and the respective distal end thereof, and connected to a fluid-dynamic system (4); said casing (2) forming a closed, rigid and inextensible casing, and allowing the transmission, to said limb (3), of pressure variations produced by said fluid-dynamic system (4); said casing (2) being openable for the insertion and removal of the limb to be treated and for maintenance; said casing (2) comprising at least three compartments (20), substantially toroidal in shape, which surround, as a whole, variously bordering or overlapping, the whole surface of the limb (3) to be treated; said fluid-dynamic system (4) performing a pressure variation within each of said compartments (20); said apparatus further comprising an electronic control system (12).

2. Apparatus (1 ), according to claim 1 , wherein the fluid-dynamic system (4) is configured to obtain within each compartment (20) a specific pressure variation, independent of the pressure variations of the other compartments (20).

3. Apparatus (1 ) according to claim 1 or 2, wherein the space (24) comprised between the casing (2) and the limb (3) is connected to a suction actuator (42).

4. Apparatus (1 ), according to one or more of the preceding claims, characterised by the fact that each of said compartments (20) is surrounded on three sides by rigid, inextensible material, including the lateral boundary part with the adjacent compartment (20), and excluding the part in contact with the skin of the limb (3) which is made of extensible material.

5. Apparatus (1 ), according to one or more of the preceding claims, further comprising one or more of sensors (8) configured to detect: temperature, pressure, flow, ECG, Po2.

6. Apparatus (1 ), according to one or more of the preceding claims, wherein the electronic control system (12) is configured to control the fluid-dynamic system (4) on the basis of one or more among:- a preloaded logic; and / or- specific parameters; and / or- data collected instantaneously by the sensors (8).

7. Apparatus (1 ) according to one or more of the preceding claims, wherein the fluiddynamic system (4) comprises an actuation unit (40) connected to a compression actuator (41 ) and a suction actuator (42).

8. Apparatus (1 ), according to the preceding claim, wherein each compartment (20) comprises a chamber (25) made of a waterproof and extensible material connected tothe actuation unit (40) of the fluid-dynamic system (4)9. Apparatus (1 ) according to the preceding claim, wherein the chamber (25) comprises within it a pocket (22) and wherein the chamber (25) is connected to a circuit (54) for supplying a liquid, and wherein the pocket (22) is connected to the actuation unit (40).

10. Apparatus (1 ) according to the preceding claim, wherein the chamber (25) comprises an elastic outer jacket (27).

11. Apparatus (1 ), according to one or more of the preceding claims, further comprising a gasket (30) configured to guarantee fluid tightness, so as to seal the space (24) comprised between the casing (2) and the limb (3).

12. Apparatus (1 ), according to one or more of the preceding claims, wherein the casing (2) is made at least partially of transparent material.

13. Apparatus (1 ), according to one or more of the preceding claims, wherein the suction actuator (42) comprises a device, based on a Venturi valve, configured to obtain the desired depression by exploiting the compressed air energy supplied by the compression actuator (41 ).

14. Apparatus (1 ), according to one or more of the preceding claims, wherein the compression actuator (41 ) and the suction actuator (42) are integrated in a single device comprising a cylindrical chamber along which a piston (6) can slide, which can alternatively perform a compression stroke or a suction stroke.

15. Apparatus (1 ), according to one or more of the preceding claims, wherein the casing (2) defines at least five compartments (20).

16. Apparatus (1 ), according to one or more of the preceding claims, comprising a fluiddynamic system (4), an electronic control system (12) and a plurality of casings (2), each configured to be wrapped around a limb (3) and the respective distal end.

Images