Negative pressure therapy device control method and negative pressure therapy device

Abstract

To provide a negative pressure treatment device control method capable of automatically filling washing fluid to a bottom part of an injury part, and a negative pressure treatment device using the same control method.SOLUTION: There is provided a control method of a negative pressure treatment device which comprises: a covering sheet 4 for sealing a wound part; liquid feeding means 9 for feeding washing fluid 1 to inside of the covering sheet sealing the wound part through a feeding channel 3; suction means 8 for maintaining a pressure at inside of the covering sheet to a negative pressure state, and sucking the washing fluid from the inside of the covering sheet through the suction channel; a container 7 which is connected to the suction channel 6, and storing the washing fluid sucked by the suction means; a pressure gauge A (2A) connected to a position where a pressure at the inside of the covering sheet can be measured; a pressure gauge B (2B) connected to a position where a pressure in the container can be measured; and an atmospheric air open path 10 for connecting through a valve, inside of the suction channel or inside of the covering sheet to atmospheric air.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a control method for a negative pressure therapeutic device that can automatically fill irrigation fluid up to the bottom of a wound, and a negative pressure therapeutic device that uses the control method for the negative pressure therapeutic device. [Background technology]

[0002] Negative pressure wound therapy is known, in which a soft, porous body (sponge-like material) that allows fluid to pass through is placed on a wound in the skin, and the porous body and the surrounding skin are covered with a covering material (such as a polymer film) to close the wound, and while maintaining negative pressure inside, fluid exuding from the wound is aspirated and drained. A device used for this type of negative pressure wound therapy is called a negative pressure treatment device (see, for example, Patent Document 1). By maintaining negative pressure while protecting the wound, granulation tissue formation is promoted. At the same time, infectious waste products and exudates are drained. As a result, blood flow around the wound increases and circulation is promoted. This restores the wound's healing function and speeds up wound healing.

[0003] A negative pressure treatment device equipped with a liquid delivery means for delivering a cleaning liquid to the inside of a covering sheet for cleaning the wound is disclosed in Patent Document 2. A negative pressure treatment device using a cleaning liquid such as that in Patent Document 2 can remove exuded waste products, attached bacteria, necrotic cells, etc., using the cleaning liquid, thereby accelerating the healing of the wound. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 4068807 [Patent Document 2] Patent No. 6195826 Summary of the Invention [Problem to be solved by the invention]

[0005] In negative pressure therapy devices using irrigation fluid, it is important for the irrigation fluid to flow near the wound surface to efficiently remove exuded waste, attached bacteria, necrotic cells, etc., in order to enhance the therapeutic effect. In treatments using conventional negative pressure therapy devices, one method of irrigating the wound is to continuously flow irrigation fluid, called perfusion irrigation. In perfusion irrigation, the process of filling the wound with irrigation fluid and the process of creating negative pressure at the wound are performed simultaneously. However, when irrigation fluid is flowed while the wound is under negative pressure, the irrigation fluid is discharged through the top of the porous material before reaching the bottom of the wound, making it difficult for the irrigation fluid to reach the wound surface, especially the bottom of the wound. In view of the above-mentioned current situation, the present invention aims to provide a control method for a negative pressure therapeutic device that can automatically fill cleaning fluid up to the bottom of a wound, and a negative pressure therapeutic device that uses the control method for the negative pressure therapeutic device. [Means for solving the problem]

[0006] The present invention provides a pressure gauge A connected to a position where the pressure inside the covering sheet can be measured; a pressure gauge B connected to a position where the pressure in the container can be measured; and an atmospheric release path connected to the atmosphere via a valve in the suction path or inside the covering sheet, the method comprising: a covering sheet for sealing a wound; a liquid delivery means for delivering a cleaning liquid through a delivery path to the inside of the covering sheet that seals the wound; a suction means for sucking the cleaning liquid from the inside of the covering sheet through a suction path while maintaining a negative pressure inside the covering sheet; a container connected to the suction path and for storing the cleaning liquid sucked by the suction means; a pressure gauge A connected to a position where the pressure inside the covering sheet can be measured; a liquid delivery step of starting the liquid delivery means to deliver the cleaning liquid to the inside of the covering sheet through the delivery flow path; a pressure difference elimination step of opening the valve and opening the inside of the covering sheet to the atmosphere until the pressure difference is eliminated when the difference in the measurements of the pressure gauge A and the pressure gauge B is equal to or greater than a predetermined set value and the measurement of the pressure gauge B is less than the predetermined set value; a cleaning liquid filling step of filling the inside of the covering sheet with cleaning liquid by repeating the pressure difference elimination step until the measurement of the pressure gauge A is equal to or greater than the set value or the measurement of the pressure gauge B is equal to or greater than the set value; and a second negative pressure step of depressurizing the inside of the covering sheet to a set pressure when the measurement of the pressure gauge A is equal to or greater than the set value or the measurement of the pressure gauge B is equal to or greater than the set value. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a control method for a negative pressure therapeutic device that can automatically fill cleaning fluid up to the bottom of a wound, and a negative pressure therapeutic device that uses the control method for the negative pressure therapeutic device. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing a schematic diagram of a negative pressure therapeutic device using the control method for a negative pressure therapeutic device of the present invention; [Figure 2]1 is a flowchart of a control method for a negative pressure therapy device of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of a method for controlling a negative pressure therapeutic device of the present invention will be described with reference to the drawings and flowcharts. The present invention provides a method for controlling a negative pressure treatment device comprising: a covering sheet that seals a wound; a liquid delivery means that delivers a cleaning liquid through a delivery flow path to the inside of the covering sheet that seals the wound; a suction means that sucks the cleaning liquid from the inside of the covering sheet through a suction flow path while maintaining a negative pressure inside the covering sheet; a container connected to the suction flow path and that contains the cleaning liquid sucked by the suction means; a pressure gauge A connected at a position where the pressure inside the covering sheet can be measured; a pressure gauge B connected at a position where the pressure in the container can be measured; and an atmospheric vent path that connects to the atmosphere via a valve in the suction flow path or inside the covering sheet.

[0010] FIG. 1 shows a schematic diagram of a negative pressure therapy device using the control method of the present invention. When using the negative pressure therapy device, a porous material 5, such as a sponge, is placed on the wound surface, and a covering sheet 4 is attached to the skin so as to cover the wound surface and the porous material 5, sealing the wound (hereinafter, the area sealed by the covering sheet is referred to as the wound). The covering sheet 4 is connected to a delivery channel 3 for supplying cleansing solution 1 to the wound and a suction channel 6 for discharging cleansing solution 1 from the wound. Cleansing solution 1 flows through the wound using a liquid delivery device 9, such as a liquid delivery pump, and a suction device 8, such as a suction pump. By flowing cleansing solution 1 while applying negative pressure to the wound using the suction device 8, granulation tissue formation is promoted, and healing inhibitors such as infectious waste products and exudates are expelled by the cleansing solution 1, promoting wound regeneration. The discharged cleansing solution 1 is collected in a container 7. Additionally, pressure gauges A2A and B2B are connected at positions where the pressure at the wound site and the pressure in the container 7 can be measured, respectively, and the pressure at the wound site and the pressure inside the container are adjusted based on the measurements of each pressure gauge. Furthermore, an atmosphere release path 10 connected to the atmosphere (outside) through a valve is provided in the suction flow path 6 or at the wound site, so that if a pressure difference occurs between the wound site and the container 7, the pressure difference can be eliminated by opening the valve and allowing the atmosphere to flow in. The locations of the pressure gauges A and B are not limited to the connection positions shown in Figure 1, as long as they are positions where the pressure at the wound site and the pressure in the container can be measured. Furthermore, the configuration of the negative pressure therapy device other than the above-mentioned components can be any conventional one without any particular limitations.

[0011] The control method for the negative pressure therapeutic device of the present invention first starts the suction means and performs a first negative pressure step in which the pressure inside the covering sheet and the container is reduced to a predetermined pressure based on the measurements of the pressure gauges A and B. In the first negative pressure step, a porous body is placed on the wound site, and a dressing sheet is applied to seal the porous body and the wound site. Then, the suction means, such as a suction pump, is started to reduce the pressure inside the dressing sheet (at the wound site) to the pressure during treatment before the cleaning solution is dispensed. At this time, the pressure in the container that collects the discharged cleaning solution is also reduced to the same pressure. The porous body placed on the wound site is compressed by the first negative pressure step. The pressure set in the first negative pressure step is not particularly limited, and may be a pressure that maximizes the therapeutic effect, such as -150 mgHg. In this specification, pressure is expressed relative to atmospheric pressure, which is set to 0.

[0012] The method for controlling a negative pressure therapeutic device of the present invention then carries out a liquid sending step of starting the liquid sending means to send the cleaning liquid to the inside of the cover sheet through the delivery flow path. In the above-mentioned fluid delivery step, the delivery of the cleaning fluid to the wound is started by the above-mentioned fluid delivery means such as a fluid delivery pump. The flow rate of the cleaning fluid in the fluid delivery step is not particularly limited, but it is preferable to make the flow rate as high as possible in order to quickly fill the wound with the cleaning fluid. Specifically, it is preferably 5 mL / min or more, more preferably 10 mL / min or more, and preferably 100 mL / min or less, and more preferably 50 mL / min or less.

[0013] In the liquid delivery step, since air is present in the delivery flow path when the cleaning liquid starts to flow, it is preferable to monitor the presence or absence of liquid using a sensor to prevent filling failure due to empty delivery, and not perform subsequent steps until the delivery flow path is filled with cleaning liquid. Furthermore, if monitoring using a sensor is not performed, it is preferable not to perform subsequent steps until a certain amount of time has passed since the start of the liquid delivery step, in order to ensure that the delivery flow path has time to be filled with cleaning liquid. The time from the start of the liquid delivery step to the start of the suction means stopping step is not particularly limited, but is preferably, for example, one minute.

[0014] The control method for the negative pressure therapeutic device of the present invention then performs a differential pressure elimination step in which, when the difference in the measurement values ​​between the pressure gauge A and the pressure gauge B (hereinafter also referred to as differential pressure) becomes equal to or greater than a predetermined set value and the measurement value of the pressure gauge B is less than the predetermined set value, the inside of the covering sheet is opened to the atmosphere until the pressure difference is eliminated. As the above-mentioned liquid delivery step continues, the cleaning liquid eventually reaches the suction channel, but as the cleaning liquid flows into the suction channel, the air connection between the container and the wound is lost, resulting in a difference in pressure between the wound and the container. This differential pressure is monitored by the above-mentioned pressure gauges A and B, and when the differential pressure exceeds a certain value and the pressure gauge measurement value is below a set value, the valve in the air release path is opened to release the wound to the atmosphere. When the wound is released to the atmosphere, air flows in and the pressure in the wound increases, so the cleaning liquid in the suction channel is swept into the container, and the air connection between the wound and the container is restored, eliminating the differential pressure.

[0015] The set value of the differential pressure is not particularly limited, but is preferably 5 mmHg or more and 30 mmHg or less. By setting the set value that eliminates the differential pressure within the above range, the rate at which the cleaning solution is filled into the wound becomes more appropriate, allowing the cleaning solution to flow more reliably to the bottom of the wound. The set value of the differential pressure is more preferably 10 mmHg or more, even more preferably 15 mmHg or more, and preferably 20 mmHg or less.

[0016] In the pressure differential elimination step, it is preferable to stop the suction means before opening the valve, and then start the suction means again after the pressure differential is eliminated and the pressure at the wound is stabilized, thereby controlling the pressure after the pressure differential is eliminated to maintain it. By controlling the pressure in this way, the cleaning liquid can be filled to the bottom more reliably.

[0017] The control method for the negative pressure therapeutic device of the present invention then performs a cleaning liquid filling step in which the differential pressure elimination step is repeated until the measurement value of the pressure gauge A becomes equal to or greater than the set value or the measurement value of the pressure gauge B becomes equal to or greater than the set value, thereby filling the inside of the covering sheet with cleaning liquid. After the pressure difference is eliminated by the pressure differential elimination step, the valve is closed and the wound is sealed again. When the irrigation fluid reaches the suction path, a pressure difference is generated again, and the same pressure differential elimination cycle is repeated. At this time, the irrigation fluid penetrates the porous body compressed by the first negative pressure step. As the pressure in the wound increases, the irrigation fluid expands and penetrates the entire porous body. Therefore, the irrigation fluid spreads throughout the entire porous body, that is, to the bottom of the wound. This allows the irrigation fluid to reach the bottom of the wound, creating a flow of irrigation fluid at the bottom of the wound during treatment. This cycle is repeated until the pressure in the wound approaches atmospheric pressure; specifically, until the measurement value of pressure gauge A reaches or exceeds the set value, or until the measurement value of pressure gauge B reaches or exceeds the set value.

[0018] The set value of the pressure gauge A at which the cleaning liquid filling step is completed is not particularly limited as long as it is close to atmospheric pressure, but is preferably -15 mmHg or higher, and more preferably -10 mmHg or higher, for example.

[0019] The set value of the pressure gauge B at which the cleaning liquid filling step is completed is not particularly limited as long as it is close to atmospheric pressure, but is preferably -25 mmHg or higher, and more preferably -15 mmHg or higher, for example.

[0020] In the pressure difference eliminating step, the flow rate of the cleaning fluid is preferably 10 mL / min or more and 100 mL / min or less. By setting the flow rate of the cleaning fluid within this range, the cleaning fluid can be more reliably flowed to the bottom of the wound.

[0021] The control method for the negative pressure therapeutic device of the present invention preferably includes a leak pressure adjustment step in which, when the difference in the measured values ​​between the pressure gauges A and B is less than a predetermined set value in the differential pressure elimination step, the pressure is adjusted so that the measured value of the pressure gauge A increases at a constant rate. If the wound is not sufficiently sealed and a large leak occurs, the wound is always open to the atmosphere, and even if the cleaning fluid reaches the suction channel, it is immediately pushed into the container, so a pressure difference may not be generated or detected. In this case, the rate at which the pressure at the wound increases cannot be controlled by the pressure difference elimination step and the cleaning fluid filling step, and the cleaning fluid may not be filled to the bottom of the wound. Therefore, by controlling the pressure so that the pressure at the wound increases at a constant rate when the pressure difference is below a set value, the cleaning fluid can be sufficiently permeated throughout the porous body, even if a leak occurs at the wound, and the cleaning fluid can reach the bottom of the wound. Note that the pressure adjustment step during leakage continues until the measurement value of the pressure gauge A reaches the set value of the pressure gauge A, which ends the cleaning fluid filling step.

[0022] The rate of increase in the measurement value of the pressure gauge A is not particularly limited as long as the cleaning liquid can penetrate the entire porous body, but it is preferably 5 mmHg / min or more, more preferably 10 mmHg / min or more, and is preferably 25 mmHg / min or less, more preferably 20 mmHg / min or less.

[0023] The control method for the negative pressure therapeutic device of the present invention then performs a second negative pressure step in which the suction means is started to reduce the pressure inside the covering sheet to the set pressure when the measurement value of the pressure gauge A reaches the set value or when the measurement value of the pressure gauge B becomes equal to or greater than the set value. In the second negative pressure step, the wound filled with the cleaning solution is again depressurized to the pressure required for treatment. When the pressure in the wound approaches atmospheric pressure through the above-mentioned irrigation fluid filling step, the compressed porous body returns to its atmospheric size and becomes filled with irrigation fluid. Then, when the pressure in the wound (measured by pressure gauge A) exceeds the set value or the pressure in the container (measured by pressure gauge B) exceeds the set value, the wound is decompressed again to the pressure required for treatment, completing the filling of the irrigation fluid into the wound and preparation for negative pressure wound therapy. At this time, the porous body is completely filled with irrigation fluid all the way to the bottom, so the irrigation fluid remains at the bottom of the wound even after the second negative pressure step. As a result, when irrigation fluid is poured during treatment, it can flow all the way to the bottom of the wound.

[0024] The set pressures of the pressure gauges A and B that start the second negative pressure step are the same as the set values ​​of the pressure gauge A that end the cleaning liquid filling step and the set values ​​of the pressure gauge B that end the cleaning liquid filling step, and the set values ​​that end the second negative pressure step are the same as the set values ​​of the first negative pressure step.

[0025] The flow rate of the cleaning liquid during the second negative pressure step is preferably 0 mL / min or more and 10 mL / min or less. The flow rate of the cleaning liquid during the second negative pressure step is more preferably 0.3 mL / min or more, and more preferably 5 mL / min or less.

[0026] Here, a flow chart of the control method for the negative pressure therapeutic device of the present invention is shown in FIG. In the flow chart, a series of steps of the present invention is shown as filling with cleaning liquid. The control method for the negative pressure therapy device of the present invention first uses the suction means to reduce the pressure at the wound and container to the treatment pressure (set pressure) (S1). After the wound and container are at negative pressure, the fluid delivery means is activated to begin delivering cleaning fluid (S2). As the cleaning fluid continues to be delivered, it reaches the suction flow path, cutting off the air communication between the wound and container, creating a pressure difference between the wound and container. When the pressure difference exceeds the set value (S3) and the pressure in the container is below the set value (S4), the valve in the atmospheric vent path is opened to open the wound to the atmosphere, restoring air communication between the wound and container and eliminating the pressure difference (S6). At this time, it is preferable to stop the suction means before opening the wound to the atmosphere (S5), and then restart the suction means after the pressure difference is resolved and stabilized, controlling the suction means to maintain the pressure at that time (S7). After the pressure difference is resolved, the atmospheric vent path is closed, and the wound is resealed. Then, when the cleaning fluid reaches the suction channel, a pressure difference is generated again, and the pressure difference is repeatedly eliminated until the pressure in the container reaches or exceeds the set value, or the pressure at the wound reaches or exceeds the set value (S3 to S7, S9). If a leak at the wound causes the pressure difference between the wound and the container to fall below the set value, it is preferable to control the suction means so that the pressure at the wound rises to the set value at a constant rate (S8). When the pressure at the container reaches or exceeds the set value after repeated elimination of the pressure difference, the entire porous body at the wound is filled with cleaning fluid, and the pressure difference elimination cycle is stopped, and depressurization of the wound begins again (S10). When the pressure at the wound reaches the set value, filling of the cleaning fluid into the wound is complete (S11).

[0027] The control method for a negative pressure therapy device of the present invention is used in the process of filling a wound with irrigation fluid, which is a step prior to performing negative pressure wound therapy. Conventional methods for filling irrigation fluid in negative pressure therapy devices involve filling the wound with irrigation fluid while depressurizing the wound. However, when filling the irrigation fluid while depressurizing, the irrigation fluid sent to the wound may reach the suction channel before spreading to the wound base, resulting in ineffective removal of waste and exudate from the wound. Furthermore, the irrigation fluid is often discharged before filling is complete, resulting in significant waste. The control method for a negative pressure therapy device of the present invention first depressurizes the wound to compress the porous body, and then gradually increases the pressure while flowing the irrigation fluid. This allows the irrigation fluid to penetrate the entire porous body, thereby ensuring that the irrigation fluid reaches the wound base. Furthermore, because the irrigation fluid is filled after first creating a negative pressure, there is no risk of the wound becoming positively pressurized and causing fluid leakage. Therefore, the control method for a negative pressure therapy device of the present invention allows irrigation fluid to be automatically filled to the wound base, enabling easier and more effective negative pressure wound therapy.

[0028] A negative pressure therapeutic device using the control method of the negative pressure therapeutic device of the present invention is also one aspect of the present invention. [Explanation of symbols]

[0029] 1 cleaning solution 2A Pressure Gauge A 2B Pressure gauge B 3. Delivery channel 4 Covering sheet 5 Porous materials 6 Suction channel 7 Container 8 Suction means 9 Liquid delivery means 10 Atmospheric release path

Claims

1. A porous body placed on the wound surface; a covering sheet that is attached to the skin so as to cover the wound surface and the porous body and seal the wound; a liquid delivery means for delivering a cleaning liquid to the inside of the covering sheet through a delivery flow path; a suction means for sucking the cleaning liquid from the inside of the covering sheet through a suction flow path while maintaining a negative pressure inside the covering sheet; a container connected to the suction flow path and configured to contain the cleaning liquid aspirated by the suction means; a pressure gauge A connected to a position where the pressure inside the covering sheet can be measured; a pressure gauge B connected to a position where the pressure of the container can be measured; A method for controlling a negative pressure therapeutic device having an atmospheric release path connected to the atmosphere through a valve in the suction flow path or inside the covering sheet, a first negative pressure step of starting the suction means and reducing the pressure inside the covering sheet and the container to a predetermined pressure based on the measurements of the pressure gauge A and the pressure gauge B; a liquid sending step of starting the liquid sending means to send the cleaning liquid to the inside of the covering sheet through the delivery flow path; a pressure difference eliminating step of opening the valve to expose the inside of the covering sheet to the atmosphere until the pressure difference is eliminated when the difference between the measurements of the pressure gauge A and the pressure gauge B becomes equal to or greater than a predetermined set value and the measurement of the pressure gauge B is less than the predetermined set value; a cleaning liquid filling step of filling the inside of the covering sheet with cleaning liquid by repeating the pressure difference eliminating step until the measurement value of the pressure gauge A becomes equal to or greater than a set value or the measurement value of the pressure gauge B becomes equal to or greater than a set value; a second negative pressure step of decompressing the inside of the covering sheet to a set pressure when the measurement value of the pressure gauge A becomes equal to or greater than a set value or when the measurement value of the pressure gauge B becomes equal to or greater than a set value. A method for controlling a negative pressure therapy device.

2. A control method for a negative pressure therapeutic device as described in claim 1, which includes a leak pressure adjustment step of adjusting the pressure so that the measurement value of pressure gauge A increases at a constant rate when the difference in the measurement values ​​of pressure gauge A and pressure gauge B in the differential pressure elimination step is less than a predetermined set value.

3. A negative pressure therapeutic device using the method for controlling a negative pressure therapeutic device according to claim 1 or 2.

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