WO2017077227A1 - Negative-pressure wound therapy simulation - Google Patents

Abstract

The invention relates to an apparatus (1) for simulating a negative-pressure wound therapy, comprising: - a wound-simulation support member (5) comprising at least one cavity (6) provided in an upper surface (7) of said support member (5); - a device (10) for simulating the secretion of exudates, suitable for feeding an exudate-simulating substance (12) into the cavity; - a fluid circuit (25) comprising at least one inlet port (26) and one outlet port (27) opening into the cavity (6); - at least one container (20) arranged in the fluid circuit (25) between the inlet port (26) and the outlet port (27) and suitable for collecting the substance (12), wherein the container (20) is positioned at a certain height (h), relative to the cavity (6), in a vertical direction (Z) perpendicular to the upper surface (7) of the wound-simulation support member (5).

Description

 SIMULATION OF NEGATIVE PRESSURE WOUND TREATMENT

The invention relates to an installation and method for simulating a negative pressure wound treatment, as well as to a method of designing a negative pressure wound treatment system implementing the simulation method. .

 A negative pressure treatment system is used to treat an open wound on a patient's body by applying a subatmospheric pressure to the wound, also known as a reduced pressure, that is, a pressure below atmospheric pressure. to help heal the wound by promoting cell migration and evacuating exudates secreted by the wound.

 The treatment system generally includes a dressing adapted to cover the wound, a vacuum source adapted to generate the subatmospheric pressure under the dressing and one or more exudate tanks adapted to collect the exudates.

 The treatment system can be portable and used for treating a wound on a lower limb of the patient. In such a situation, for practical and comfort reasons, the exudate reservoir is generally worn on the belt by the patient. The different components of the treatment system are then located at different heights resulting in pressure differences within the treatment system.

 In the context of a treatment system used in a hospital environment, the nursing staff tries to circumvent this problem by arranging the various components of said system and in particular the reservoir at the same height as that of a bedridden patient.

 However, the effectiveness of a negative pressure treatment is conditioned by control and control of the subatmospheric pressure in the treatment system.

Document US 2008/0077091 describes a simulation installation of a negative pressure wound treatment intended to measure the effectiveness of a negative pressure treatment system in order to adapt it to the type of wound to be treated. The installation comprises a device for exudate secretion simulation comprising a container adapted to collect a substance simulating exudates. The flow of substance feeding a cavity that simulates a wound is controlled to be maintained at a preselected level and the amount of exudates collected in the container is measured. Nevertheless, there is a need to be able to improve the control and control of the subatmospheric pressure in the treatment system, in particular with a view to treating a wound on a lower limb of the patient with a portable treatment system, or for the treatment of wounds of a bedridden patient by a so-called "classic" treatment system exceeding any consideration of disposition.

 The invention aims to satisfy this need.

 For this purpose, according to a first aspect, the invention proposes a simulation installation of a negative pressure wound treatment for a negative pressure wound treatment system comprising a dressing adapted to cover a wound, a suitable vacuum source. for generating a subatmospheric pressure under the dressing, and at least one exudate tank adapted to collect exudates secreted by the wound, the simulation apparatus comprising:

 a wound simulation support comprising at least one cavity simulating a wound, formed in an upper surface of the wound simulation support and intended to be covered by the dressing of the negative pressure wound treatment system,

 an exudate secretion simulation device adapted to supply the cavity of the wound simulation support with a substance simulating exudates,

 a fluid circulation circuit comprising at least one input port adapted to be connected to the vacuum source of the negative pressure wound treatment system, and at least one output port opening into the cavity of the simulation support medium; wound,

 at least one container disposed in the fluid circulation circuit between the inlet and outlet ports and adapted to collect the substance,

 wherein the container is placed in height, in a vertical direction normal to the upper surface of the wound simulation support, relative to the cavity.

 Thus, the installation according to the invention makes it possible to simulate the difference in height between the dressing and the exudate tank in order to control the resulting pressure difference and to be able to control it by adapting the treatment system.

 According to particular provisions, the simulation installation makes it possible to take into account the difference in height between the dressing and the exudate reservoir during the design of the treatment system, in particular by choosing and dimensioning the vacuum source appropriately.

 The simulation facility may further include a height adjustment device on which the container is movably mounted in the vertical direction.

The simulation facility may further include: a measuring device adapted to measure a pressure in the fluid circulation circuit,

 a processing unit connected to the measuring device and adapted to collect data concerning the subatmospheric pressure as a function of the height of the container.

 The processing unit can be adapted to determine the subatmospheric pressure to be generated depending on the height of the container.

 The upper surface of the wound simulation support may extend substantially in a horizontal plane, the fluid circulation circuit extending generally in the plane of the upper surface of the wound simulation support.

 According to a second aspect, the invention proposes a method of simulating a negative pressure wound treatment implementing the simulation installation as defined above, the simulation method providing the steps of:

 - cover the cavity of the wound simulation support with the dressing of the negative pressure wound treatment system,

 placing in fluid communication the cavity of the wound simulation support and the vacuum source of the negative pressure wound treatment system by the fluid circulation circuit,

 to generate the subatmospheric pressure in the cavity under the dressing,

feeding the cavity of the wound simulation support into a substance simulating exudates by the device for exudate secretion simulation.

 The simulation method may further include the step of varying the height of the container by moving said container in the vertical direction.

 The simulation method may further include the step of measuring a pressure in the fluid circulation circuit, and collecting data relating to the subatmospheric pressure as a function of the height of the container.

 The simulation method may furthermore provide the step of determining the subatmospheric pressure to be generated as a function of the height of the container.

 According to a third aspect, the invention provides a method of designing a negative pressure wound treatment system comprising the steps of:

selecting at least one of a dressing adapted to cover a wound, a source of vacuum adapted to generate a subatmospheric pressure under the dressing and an exudate tank adapted to collect exudates secreted by the wound; implement the simulation method as defined above. The design method may provide, during the step of selecting a vacuum source, to select the vacuum source adapted to generate the subatmospheric pressure adapted to a height of use of the exudate tank.

 Other objects and advantages of the invention will appear on reading the following description of a particular embodiment of the invention given by way of non-limiting example, the description being made with reference to the appended drawings in which :

 FIG. 1 is a schematic representation of a simulation installation of a negative pressure wound treatment for the implementation of a method for simulating such a treatment according to one embodiment of the invention,

 FIG. 2 is a diagrammatic representation in perspective of the simulation installation of FIG. 1 during the implementation of the simulation method, a dressing of a negative pressure wound treatment system covering a cavity simulating a wound. of the simulation installation, and a source of vacuum of the negative pressure wound treatment system being placed in fluid communication with the cavity by a fluid circulation circuit of the installation,

 FIG. 3 is a flowchart illustrating the steps of the simulation method implemented on the simulation installation of FIG. 1 applied to a method of designing a negative pressure wound treatment system.

 In the figures, the same references designate identical or similar elements.

 FIGS. 1 and 2 show a simulation installation of a negative pressure wound treatment 1 adapted in particular for controlling, testing, analyzing or designing a negative pressure wound treatment system.

 A negative pressure wound treatment system generally comprises a dressing 2, a vacuum source 3 and one or more exudate tanks adapted to collect exudates secreted by the wound.

 The dressing 2, shown diagrammatically in FIG. 2, is of any suitable type and comprises one or more layers adapted to cover a wound and to be secured to the edges of the wound. The dressing 2 may also comprise a connection interface 4 adapted to put a lower surface of the dressing 2 intended to be placed facing the wound in fluid communication with the vacuum source 3.

The vacuum source 3, shown schematically in FIG. 2, is also of any type suitable for generating a subatmospheric pressure under the dressing 2. The vacuum source 3 can in particular be of the active type, such as a pump electromechanical or vacuum network, or passive type, such as a vacuum supply or a hand pump.

 The simulation installation 1 comprises a wound simulation support 5 comprising a cavity 6 simulating a wound formed in an upper surface 7. In the embodiment, the wound simulation support 5 is in the form of a plate parallelepiped whose upper surface 7 extends substantially horizontally in a plane P. Moreover, the cavity 6 is also of parallelepiped shape. Alternatively, the wound simulation support 5 and the cavity 6 may have any other form suitable for the simulation of a particular wound on a particular body part.

 Two ducts 8, 9 are formed in the wound simulation support 5 to open each, on the one hand, on an outer surface of the plate and, on the other hand, on an inner surface of the plate delimiting the cavity 6.

 One of the ducts 8 is placed in fluid communication with an exudate secretion simulation device 10 made, in the embodiment shown, in the form of a syringe 11. The syringe 11 is filled with a substance 12 simulating the exudates so as to simulate the secretion of exudates by actuating a piston 13 of the syringe 11. As a variant, the exudate secretion simulation device 10 could be made anyway to supply the cavity 6 of the wound simulation support 5 with substance 12.

 The other conduit 9 forms part of a passage of a leak generation device 15 placing in fluid communication the cavity 6 of the wound simulation support 5 with an external atmosphere and, in particular, with the ambient air at atmospheric pressure. In the embodiment, the passage also comprises a pipe 18 connected to the conduit 9 and having two branches on which two valves 16, 17 are mounted respectively. Each of the valves is suitable for:

 in an active state of the leak generation device, allow an introduction of ambient air at atmospheric pressure into the cavity of the wound simulation support with a flow rate of introduction of gaseous fluid, and

 - in an inactive state of the leak generation device 15, preventing the introduction of ambient air into the cavity 6 of the wound simulation support 5.

In particular, the valves 16, 17 of the leak generation device 15 are variable opening valves adapted for, in the active state of the leak generation device 15, to vary the rate of introduction of gaseous fluid into the passage 9, 18 and, in the idle state of the leak generation device 15, closing the passage 9, 18. One of the valves 16 is, for example, a micrometric screw adjustable valve 10 ml / h adapted to vary. the rate of introduction of gaseous fluid between 0 ml / h and 10 ml / h and simulate very low flow leakage related in particular to the permeability of dressing 2 of the treatment system. The other valve 17 is, for example, a micrometric screw adjustable valve 1000 ml / h adapted to vary the rate of introduction of gaseous fluid between 0 ml / h and 1000 ml / h and to simulate larger flow leakage. particularly related to leaks at the connections between the components of the treatment system or at the interface between the dressing 2 of the treatment system and the edges of the wound to which it is attached.

 Alternatively, the leak generation device 15 could comprise several passages and one or more valves each adapted to vary the rate of introduction of gaseous fluid between 0 ml / h and 1000 ml / h, in particular between 0 ml and 500 ml / h, in particular between 0 ml / h and 100 ml / h, preferably between 0 ml / h and 50 ml / h, more preferably between 0 ml / h and 10 ml / h. In addition, each passage of the leak generation device 15 could put the cavity 6 of the wound simulation support 5 in fluid communication with an external atmosphere comprising a gaseous fluid other than the ambient air and at any leakage pressure greater than the subatmospheric pressure in the cavity 6 of the simulation support 5 when the vacuum source is activated.

 The simulation installation 1 also comprises a container 20 adapted to collect the substance 12 delivered by the exudate secretion simulation device 10. Alternatively, the simulation installation could comprise several containers 20.

 In the embodiment shown, the container 20 has a specific capacity, for example similar to that of the exudate tank (s) of the negative pressure wound treatment system. The container 20 is mounted movable in a vertical direction Z, normal to the upper surface 7 of the wound simulation support 5, on a height adjustment device 21 so as to be placed at a height h of the cavity 6. In In particular, the height adjustment device 21 comprises a mast 22 extending in the vertical direction Z and on which a carriage 23 adapted to carry the container 20 is slidably mounted. A locking member, not shown, can then be provided to hold the carriage 23 and the container 20 at the desired height.

In order to be able to put in communication fluid the cavity 6 of the wound simulation support 5, the container 20 and the vacuum source 3, the simulation installation 1 comprises a fluid circulation circuit 25 extending between a port of input 26 adapted to be connected to the vacuum source 3 of the treatment system, and an output port 27 opening into the cavity 6 of the wound simulation support 5. Alternatively, a plurality of input ports 26 and / or Output 27 could be provided to use the simulation facility with multiple negative pressure wound therapy systems. The fluid circulation circuit 25 comprises a pipe consisting of conduits adapted to allow the circulation of air and exudates in a sealed manner so as to create a subatmospheric pressure and evacuate the exudates. A first pipe 31 extends between a first end 31a forming the input port 26 in the vicinity of which a first solenoid valve 33 is provided, and a second end 31b placed in the vicinity of an opening 20a of the container 20. A second conduit 32 extends between a first end 32a placed in the vicinity of a bottom 20b of the container 20 and a second end 32b forming the output port 27. The output port 27 is adapted to be placed in fluid communication with the The container 20 is thus disposed in the fluid circulation circuit 25 between the inlet port 26 and outlet port 27.

 In order to be able to perform a simulation with a static vacuum source 3, i.e. with a vacuum source comprising a finite and determined amount of vacuum, the fluid circulation circuit 25 comprises one or more vacuum tanks 35. each connected to the tubing via a valve, in particular a second solenoid valve 36, adapted to selectively put the vacuum tank 35 in fluid communication with the tubing and isolate the vacuum tank 35 relative to the tubing. In the embodiment shown, three vacuum tanks 35 of different capacities, for example 50 ml, 100 ml and 200 ml, are connected to the first pipe 31.

In order to be able to perform a simulation with a continuous vacuum source, such as a vacuum network, the fluid circulation circuit 25 may also comprise a flow limiter 37 and a flow regulator 38. In particular, the flow restrictor 37 is placed on the first pipe 31, in the vicinity of the inlet port 26, upstream (with respect to the direction of fluid circulation when the vacuum source 3 is actuated to generate the subatmospheric pressure) of the first solenoid valve 33. flow controller 38 is also placed on the first pipe 31, upstream (with respect to the direction of fluid flow when the vacuum source 3 is actuated to generate the subatmospheric pressure) of the flow limiter 37. To be able to do without the the use of the flow regulator 38, especially when the vacuum source 3 used comprises its own regulator, a bypass 39 is connected to the first pipe 31, upstream and downstream of the flow regulator 38. A third solenoid valve 40 is mounted on the bypass 39 and two fourth solenoid valves 41 are mounted on the first pipe 31 respectively in the vicinity of an inlet and an outlet of the flow regulator 38 to guide the fluid flow through the flow regulator 38 or in the bypass 39. At least portions of the first 31 and second 32 conduits connected to the container 20 may be flexible to adjust the height h of the container 20 without having to replace them. With the exception of these portions of the first 31 and second 32 conduits, most of the fluid circulation circuit 25 extends in the plane P of the upper surface 7 of the wound simulation support 5. In particular, the port 26, the flow limiter 37, the vacuum tanks 35, the flow regulator 38 and the portion of the first pipe 31 connecting them are generally placed in the plane P of the upper surface 7 of the wound simulation support 5. Alternatively, a branch line 32 ', shown in dashed lines in FIG. 2, could extend in the plane P to connect the first line 31, upstream of the flow regulator 38 and the branch line between the first pipe 31 and the bypass 39, at the outlet port 27. Valves not shown can then ensure proper circulation in the fluid circulation circuit 25 either through the container 20 or in the bypass line 32 '.

 In order to be able to control the simulation installation 1 during its operation and to collect data, a measuring device is provided. The measuring device is in particular adapted to measure a pressure in the fluid circulation circuit 25. It comprises, for this purpose, one or more pressure sensors 45 adapted to measure a pressure P in the fluid circulation circuit 25. in particular, three pressure sensors 45 are provided respectively on the first pipe 31 for measuring the pressure upstream and downstream of the branches between the first pipe 31 and the bypass 39, and on the wound simulation support 5 for measuring the pressure in the pipe. the cavity 6.

 A processing unit 46 is connected, wired or wirelessly, to the measuring device for recording and processing the collected data, particularly with regard to the pressure in the fluid circulation circuit 25. In particular, the processing unit is adapted to collect data concerning the subatmospheric pressure as a function of the height h of the container 20 and in particular to determine the subatmospheric pressure to be generated as a function of the height h of the container 20. The processing unit 46 can then also be connected to the vacuum source 3 so as to control it according to the data collected and their treatment.

 FIG. 3 represents the steps of a simulation method implementing the simulation installation 1 applied to a method of designing a negative pressure wound treatment system.

The design method provides an initial step of choosing a dressing 2 adapted to cover a wound, a vacuum source 3 adapted to generate subatmospheric pressure under the dressing and one or more exudate tanks to collect exudates secreted by the wound.

 Although described in connection with a design method providing for the aforementioned initial step, the simulation method applies to any other type of method and in particular a method of controlling, testing or analyzing a processing system of negative pressure wound.

 The design process continues with the implementation of the simulation process.

 The negative pressure treatment system is installed on the simulation facility 1. In particular, as illustrated in FIG. 2, the cavity 6 of the wound simulation support 5 is covered with the dressing 2 of the treatment system, and the vacuum source 3 of the treatment system is connected to the input port 26 of the treatment system. fluid circulation circuit 25 so as to put in fluid communication the cavity 6 of the wound simulation support 5 and the vacuum source 3 of the treatment system.

 The vacuum source 3 can then be activated to generate the subatmospheric pressure in the cavity 6 under the dressing 2.

 The exudate secretion simulation device can then be activated to supply the cavity 6 of the wound simulation support 5 with substance 12 simulating the exudates.

 The container 20 is positioned at a desired height h and the subatmospheric pressure in the fluid circulation circuit 25 is measured. The subatmospheric pressure for the container placed at height h is recorded by the processing unit. Such a measurement makes it possible to collect data concerning, in particular, the influence of the height h of the container 20 as the container 20 becomes filled with substance 12.

 The height h of the container 20 can be changed in order to collect the data concerning the subatmospheric pressure as a function of the height h of the container 20.

 The processing of these data can make it possible to establish a relationship between the subatmospheric pressure to be generated and the height h of the container 20 so that, when designing a negative pressure wound treatment system, for example, the source vacuum 3 is adapted to generate the subatmospheric pressure corresponding to a height of use of the exudate tank.

Claims

1. Negative pressure wound therapy simulation facility (1) for a negative pressure wound treatment system comprising a dressing (2) adapted to cover a wound, a vacuum source (3) adapted to generate a subatmospheric pressure under the dressing (2), and at least one exudate reservoir adapted to collect exudates secreted by the wound, the simulation facility (1) comprising:  a wound simulation support (5) comprising at least one cavity (6) simulating a wound formed in an upper surface (7) of the wound simulation support (5) and intended to be covered by the dressing (2) Negative pressure wound therapy system,  an exudate secretion simulation device (10) adapted to supply the cavity (6) of the wound simulation support (5) with a substance (12) simulating exudates,  a fluid circulation circuit (25) having at least one input port (26) adapted to be connected to the vacuum source (3) of the negative pressure wound treatment system, and at least one output port (27) opening into the cavity (6) of the wound simulation support (5),  at least one container (20) disposed in the fluid circulation circuit (25) between the inlet (26) and outlet (27) ports and adapted to collect the substance (12), the simulation facility ( 1) being characterized in that the container (20) is placed in height (h), in a vertical direction (Z) normal to the upper surface (7) of the wound simulation support (5), with respect to the cavity (6).  2. simulation facility (1) according to claim 1, further comprising a height adjustment device (21) on which the container (20) is movably mounted in the vertical direction (Z).  3. Simulation facility (1) according to claim 1 or 2, further comprising:  a measuring device (45) adapted to measure a pressure in the fluid circulation circuit (25),  - a processing unit (46) connected to the measuring device (45) and adapted to collect data concerning the subatmospheric pressure as a function of the height (h) of the container (20). 4. simulation facility (1) according to claim 3, wherein the processing unit (46) is adapted to determine the subatmosphérique pressure to be generated as a function of the height (h) of the container (20). 5. Simulation installation (1) according to any one of claims 1 to 4, wherein the upper surface (7) of the wound simulation support (5) extends substantially in a horizontal plane (P), the circuit fluid circulation device (25) extending generally in the plane (P) of the upper surface (7) of the wound simulation support (5).  6. A method of simulating a negative pressure wound treatment implementing the simulation facility (1) according to any one of claims 1 to 5, the simulation method comprising the steps of:  - covering the cavity (6) of the wound simulation support (5) with the dressing (2) of the negative pressure wound treatment system,  - placing in fluid communication the cavity (6) of the wound simulation support (5) and the vacuum source (3) of the negative pressure wound treatment system by the fluid circulation circuit (25),  - generating the subatmospheric pressure in the cavity (6) under the dressing (2), - feeding the cavity (6) of the wound simulation support (5) into a substance (12) simulating exudates by the exudate secretion simulator (10).  The simulation method according to claim 6, further comprising the step of varying the height (h) of the container (20) by moving said container (20) in the vertical direction (Z).  The simulation method according to claim 6 or 7, further comprising the step of measuring a pressure in the fluid circulation circuit (25), and collecting subatmospheric pressure data as a function of height (h). ) of the container (20).  The simulation method according to claim 8, further comprising the step of determining the subatmospheric pressure to be generated as a function of the height. (h) the container (20).  A method of designing a negative pressure wound treatment system comprising the steps of:  - choose at least one of a dressing (2) adapted to cover a wound, a vacuum source (3) adapted to generate a subatmospheric pressure under the dressing (2) and an exudate tank adapted to collect exudates secreted by the wound,  implementing the simulation method according to any one of claims 6 to 9. 1 1. A design method according to claim 10 when dependent on claim 9, providing during the step of selecting a vacuum source (3), to choose the vacuum source (3) adapted to generate the subatmospheric pressure adapted to a height of use of the exudate tank.