KR20230149553A - Ultra-thin patch-type skin strain sensor for early detection of infiltration, and early detection and notification system using it - Google Patents

Abstract

The present invention is an ultra-thin patch-type skin strain sensor for early detection of infiltration that can detect and monitor infiltration-causing phenomena in patients during intravenous therapy in real time using a nano-based skin-attached ultra-thin patch-type skin strain sensor, and an early infiltration detection and notification system using the same. It's about.
The present invention is intended to solve the problem of difficulty in detecting infiltration at an early stage, mainly because nurses intermittently observe the patient's intravenous therapy site, and detect infiltration using an ultra-thin patch-type skin strain sensor for early detection of infiltration. By accurately detecting triggers early and preventing the occurrence of fatal side effects, the workload of nurses can be greatly reduced. By monitoring infiltration phenomena that frequently occur during the administration of intravenous therapy in real time, valid information is provided. By acquiring the infiltration, it is possible to detect it early and accurately when infiltration is induced, and the infiltration-inducing signal detected by the ultra-thin patch-type strain sensor-based early infiltration detection system is notified to the nurse and attending physician's smartphone through wireless communication, allowing quick follow-up action. It works.

Description

Ultra-thin patch-type skin strain sensor for early detection of infiltration, and early detection and notification system using it {Ultra-thin patch-type skin strain sensor for early detection of infiltration, and early detection and notification system using it}

The present invention relates to an ultra-thin patch-type skin strain sensor for early detection of infiltration and an early detection and notification system for infiltration using the same. Specifically, a nano-based ultra-thin patch-type skin strain sensor for skin attachment was designed and manufactured to detect the risk of damage caused by patients undergoing intravenous therapy. This study relates to an ultra-thin patch-type skin strain sensor for early detection of infiltration that can detect infiltration in real time and an early detection and notification system for infiltration using the same.

Intravenous therapy is a treatment that involves injecting fluids and medications into the patient's veins. It is the most unilaterally invasive treatment performed on hospitalized patients. It is a major task that occupies a large proportion and time of clinical nursing work, but is frequently triggered during intravenous therapy. The phenomenon of infiltration or extravasation cannot be detected early.

In Korea, the scale of intravenous therapy is more than 90% of hospitalized adult patients and 63.8% of children, and is performed more than 100 million times a year. In foreign countries, it is performed on more than 80% of hospitalized patients. . For example, in the United States, approximately 153 million people are undergoing the treatment annually (data source: U.S. ivWatch model 400 data).

In Korea, the incidence of infiltration during intravenous therapy is approximately 18.7% in adults and approximately 16-78% in children (data source: Yonsei University Professor Jong-min Lee's thesis in 2016, Infiltration and extravasation incidence and risk factors during peripheral intravenous injection in adults). In the United States, it was reported to be about 20-50% (data source: ivWatch LLC, USA).

In addition, as the number of high-risk groups for infiltration in Korea (elderly people, cancer patients, sick children, etc.) increases rapidly, the incidence of infiltration during intravenous therapy is expected to increase further. For reference, the number of seniors aged 65 or older was 6.38 million in 2014. It is expected to increase from 6,000 (12.7%) to 12,961,000 (24.3%) in 2030, and the cancer incidence rate also increased from 219.9 per 100,000 in 1999 to 319.5 per 100,000 in 2012, an annual average of 3.5%. .

As known in Non-Patent Document 1, intravenous therapy can cause infiltration and related complications may occur, no matter how skilled a nurse or doctor is, and if infiltration is induced, in actual clinical practice, intravenous therapy must be discontinued and Rework and treatment must be performed.

Therefore, various methods have been proposed and patent applications are being filed for early detection of the infiltration phenomenon that frequently occurs during intravenous therapy as described above.

Patent Document 1 relates to a tissue monitoring system for intravascular injection. As shown in FIG. 1, the sensors 120 disposed within the film barrier dressing 122 of the sensor dressing 118 are bioimpedance, spectrometer, and spectrophotometer. It was composed of etc. And Patent Document 2 relates to a fluid monitoring device, and as shown in FIG. 2, an optical measurement unit (1U 1) for upstream and downstream of the surface of the blood vessel area of the patient's skin (S) where the fluid is injected (1U ₁ ) ( 1D ₁ ) are each arranged, and it is determined whether fluid is leaking out of the patient's blood vessels based on the detection value of the light intensity reflected from the blood vessels of light of a predetermined wavelength irradiated toward the patient's blood vessels.

The above patent documents 1 and 2 are inventions related to technology for early detection of infiltration phenomenon that frequently occurs during intravenous therapy using bioimpedance and optical sensors. Although infiltration-causing phenomenon can be detected early, the early detection rate of infiltration induction is low. It is not commercialized because it is low and does not have the function of wirelessly notifying medical staff.

However, the optical detection device for venous invasion in Patent Document 3, developed and patented by ivWATCH in the United States, has a needle injection site where the needle 540 is inserted into the vein 560 through the skin 300, as shown in FIG. 3. An optical fiber bundle 270 including a light guide 50 for irradiating light and a light receiver 80 for collecting reflected light reflected from the injection site tissue, and the ends of the light guide 50 and the light receiver 80 are connected to the skin. It is commercialized as an early detection and notification device for invasion using an optical sensor built into the skin contact sensor (200) that is in contact with (300).

However, in most hospitals, nurses still check the presence of infiltration with the naked eye at certain intervals or when changing fluid bags, making it difficult to detect infiltration-inducing phenomena early, and situations in which infiltration-inducing conditions are often left unattended. Problems that result in patients experiencing discomfort and side effects often occur.

Republic of Korea Patent Publication No. 10-2004-0095210 (published on November 12, 2004) Tissue monitoring system for intravascular injection Japanese Patent Publication No. 2016-179019 (published on October 13, 2016) Sap monitoring device U.S. Patent Publication No. 7826890 (registered on November 2, 2010) Optical detection of intravenous infiltration

Seong Se-hee, Kim Hee-sun "Analysis of risk factors for intravenous infiltration in children" Clinical Nursing Research Vol. 13, No. 2, 61-72. 2007.08.

As a way to improve the above problems, the present invention is attached directly to the patient's skin and detects infiltration-causing phenomenon early by sensitively detecting changes in skin strain caused by infiltration phenomenon that frequently occurs during intravenous therapy. The goal is to provide an ultra-thin patch-type skin strain sensor for early detection of infiltration and an early detection and notification system of infiltration using the same.

The present invention is an ultra-thin patch-type skin strain sensor for early detection of infiltration that can be used in combination with or as a replacement for transparent dressings without an infiltration detection function used when performing existing intravenous therapy. It is easy to attach and wear on the body's skin, providing patient benefit. Another task is to provide an ultra-thin patch-type skin strain sensor for early detection of infiltration, which is characterized by not causing inconvenience and enabling rapid treatment by notifying medical staff through wireless communication, and an early detection and notification system of infiltration using the same.

According to the features of the present invention for achieving the above-described object, the upper layer 11 made of a metal thin film 110 in which cracks are formed, as shown in Figure 4; An intermediate layer (12) made of a conductive composite in which metal nanomaterial (113) is embedded; and a lower layer 13 made of an elastic polymer 114; an ultra-thin patch-type skin strain sensor for early detection of infiltration is used as a means of solving the problem.

The upper layer 11 is made of a metal thin film 110 arranged so that a crack gap 112 is formed between a plurality of metal thin film pieces 111, and the middle layer 12 is elastic. It is characterized in that the metal nano material (113) is uniformly dispersed and distributed within the polymer (elastomer) (114).

In addition, the metal thin film piece 111 is a material selected from gold, silver, copper, aluminum, or platinum, and the metal nanomaterial 113 is a nano wire, nanoparticle, or flake. , can be applied in various shapes such as sheets, and the elastomer 114 is polydimethylsiloxane, dragon skin elastomer, ecoflex elastomer, poly It is characterized by being applicable to a variety of butadiene elastomers, silicone elastomers, and polyurethane.

In addition, the present invention includes an ultra-thin patch-type skin strain sensor (10) that detects infiltration caused by a patient undergoing intravenous therapy and detects skin swelling caused by infiltration using a skin strain sensor; A detection unit 20 that converts the strain of resistance due to the applied strain into a voltage signal and transmits it to the built-in control unit 30 below; And a built-in control unit (30) that converts the voltage signal into a digital signal to wirelessly notify the medical staff of the infiltration-causing state and sounds an alarm bell (40) depending on the degree of infiltration. An ultra-thin patch-type skin strain sensor for early detection of infiltration, including a An early detection and notification system for invasion using this is another means of solving the problem.

The present invention is intended to solve the problem of difficulty in detecting infiltration at an early stage, mainly because nurses intermittently observe the patient's intravenous therapy site, and detect infiltration using an ultra-thin patch-type skin strain sensor for early detection of infiltration. It has the effect of detecting early and accurately, preventing the occurrence of side effects due to infiltration in advance, and at the same time significantly reducing the workload of nurses.

In addition, the present invention monitors infiltration-inducing phenomena that frequently occur during intravenous therapy in real time and obtains effective information, enabling early and accurate detection when infiltration is induced, and an ultra-thin patch-type strain sensor-based early detection and notification system for infiltration. It has the effect of enabling rapid follow-up measures by notifying the infiltration-causing signal detected by wireless communication to the smartphone of the medical staff (attendant, nurse in charge).

In addition, the present invention uses an ultra-thin patch-type skin strain sensor for early detection of infiltration that can be used in combination with or as a replacement for transparent dressings without an infiltration detection function used when performing existing intravenous therapy, making it easy to attach and wear on the skin of the body. It has the effect of causing no discomfort to the patient.

1 is a schematic diagram illustrating an injection system that has the ability to monitor tissue status as a conventional technology.
Figure 2 is a schematic diagram to explain the principle of detecting extravascular leakage using another conventional technology.
Figure 3 is a cross-sectional view illustrating a device that detects an infiltration-inducing phenomenon using an optical technique as another conventional technology.
Figure 4 is a cross-sectional view illustrating an ultra-thin patch-type skin strain sensor for early detection of infiltration according to a preferred embodiment of the present invention.
Figure 5 is a diagram for explaining the manufacturing process of the ultra-thin patch-type skin strain sensor for early detection of infiltration of Figure 4.
FIG. 6 is a diagram for explaining the operating principle of the ultra-thin patch-type skin strain sensor for early detection of infiltration of FIG. 4.
Figure 7 is a diagram to explain the difference in representative characteristics between a general metal thin film crack-based strain sensor and an AgNW/polymer composite-based strain sensor.
Figure 8 is a diagram to explain the operating principle and performance of the metal thin film/AgNW/polymer composite-based strain sensor according to the present invention.
FIG. 9 is a diagram to illustrate and compare trends in general characteristics of a metal thin film crack-based strain sensor, an AgNW/polymer composite-based strain sensor, and a metal thin film/AgNW/polymer composite-based strain sensor.
Figure 10 is a configuration diagram illustrating an early detection and notification system for infiltration using an ultra-thin patch-type skin strain sensor for early detection of infiltration according to a preferred embodiment of the present invention.
Figure 11 is a perspective view to explain the early detection and notification system of invasion using the ultra-thin patch-type skin strain sensor for early detection of invasion of Figure 10.
Figure 12 is a circuit diagram showing the circuit configuration of the detection unit of the early detection system for invasion using an ultra-thin patch-type skin strain sensor for early detection of invasion according to the present invention.
Figure 13 is a photograph taken of an experiment to confirm the possibility of detecting skin expansion by demonstrating a balloon using the ultra-thin patch-type skin strain sensor according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail based on the accompanying drawings, and components performing the same function in Figures 4 to 13 will be denoted by the same reference numerals. Meanwhile, in the illustrations and detailed descriptions of the drawings, detailed descriptions and illustrations of specific technical configurations and operations of elements that are not directly related to the technical features of the present invention are omitted, and only the technical configurations related to the present invention are briefly shown. explained.

The ultra-thin patch-type skin strain sensor 10 (hereinafter referred to as 'ultra-thin patch-type skin strain sensor') for early detection of infiltration used in the early detection system of infiltration according to a preferred embodiment of the present invention is used for early detection of infiltration. As shown in Figure 4, an upper layer 11 made of a metal thin film 110 in which cracks are formed; An intermediate layer (12) made of a conductive composite in which metal nanomaterial (113) is embedded; and a lower layer 13 made of an elastic polymer 114 having elasticity.

The upper layer 11 is a layer made of a metal thin film 110 arranged so that a crack gap 112 is formed between a plurality of metal thin film pieces 111, and is formed to prevent mechanical cracks. A layer that controls the flow of electrons through the opening and closing of cracks caused by external force applied to the formed metal thin film 110, thereby detecting strain (ε) applied from the outside. am.

The middle layer 12 is a conductive composite layer in which a metal nano material 113 is uniformly dispersed and distributed within an elastomer 114, and is of the same or different type as the substrate material. A conductive composite in which a metal nanomaterial 113 is embedded in an elastomer 114 controls the shape of a mechanical crack induced in the metal thin film of the upper layer 111, It is a layer that serves as a conductive bridge in the crack gap 112 when the crack is opened by the application of external force.

The lower layer 13 is an elastomer 114 with mechanical elasticity and is a layer used as a substrate that serves as the body of an ultra-thin patch-type strain sensor.

The ultra-thin patch-type skin strain sensor 10 having the structure as described above is composed of a stretchable structure with three functional layers, and the shape of the sensor can be adjusted according to the manufacturer's needs or the consumer's needs according to the application purpose. The shape dimensions such as width, length, and thickness of the sensor can be freely designed.

The manufacturing process of the ultra-thin patch type skin strain sensor 10 will be described with reference to FIG. 5 as follows.

First, the metal nanomaterial 113 is coated on the upper surface of the donor substrate 90 using a spray coating technique with a metal nanomaterial dispersion solution to form a metal nanomaterial percolation network film. forms.

At this time, metal nanomaterials In addition to spray coating, percolation network film can be formed by applying various coating techniques such as spin coating, bar coating, dip coating, and drop coating.

In addition, the metal nanomaterial dispersion solution is a solution in which the metal nanomaterial 113 is dispersed in a solution such as ethanol, methanol, or isopropanol in order to coat the upper surface of the donor substrate 90 with the metal nanomaterial 113. By adjusting the concentration or coating amount of the coating solution, the network density of the film, the film thickness, and the resulting electrical characteristics can be easily controlled, and through this process, the characteristics of the sensor can be controlled.

Metal nanomaterials used as conductive materials can be composed of various metal materials such as gold (Au), silver (Ag), copper (Cu), aluminum (Al), and platinum (Pt), and metal nanomaterials include nanowires ( In addition to nano wire shapes, conductive nanomaterials of various shapes such as nanoparticles, flakes, sheets, etc. can be used.

And a metal nanomaterial formed on the upper surface of the donor substrate (90). An elastomer 114 is coated on the percolation network film, cured through heat treatment, and then separated from the donor substrate 90 to create a composite substrate with a metal nanomaterial/elastomer layer formed on the surface area of the elastomer substrate. Produce. Afterwards, a metal thin film 110 is deposited on the conductive composite side of the substrate, and a mechanical crack is induced through tension to complete the production of the ultra-thin patch-type skin strain sensor 10.

Metal nanomaterials formed through elastomer coating and heat treatment Spin-coat an elastomer (114) mixed with a liquid base material and a curing agent on the percolation network film, and the elastomer (114) is a metal nanomaterial. It is maintained in a vacuum desiccator to allow sufficient penetration between networks.

Thereafter, the elastomer 114 is hardened through thermal curing to form the middle layer 12 of the metal nanomaterial/elastomer composite and the lower elastomer substrate layer 113 at the same time. At this time, the thickness ratio between the middle layer and the lower layer can be easily adjusted by adjusting the spin speed during elastomeric spin coating.

In addition, the elastomer 114 constituting the elastic substrate and the conductive composite can be selected from materials such as polydimethylsiloxane, polybutadiene elastomer, silicone elastomer, or polyurethane. . Types of silicone elastomers vary by manufacturer, such as BASF's ecoflex, RADIO FREQUENCY SYSTEMS' dragon skin, and Smooth-On Inc's smooth-sil. is being distributed.

In manufacturing a metal nanomaterial/elastomer composite substrate, in order to prepare a metal nanomaterial/elastomer composite substrate, the elastomer is heat treated and then separated from the main substrate 90.

Then, a metal thin film 110 is deposited on the surface of the conductive composite of the prepared metal nanomaterial/elastomer composite substrate using sputtering or evaporation technology. At this time, various metal materials such as gold, silver, copper, aluminum, and platinum can be applied as the metal thin film.

In order to induce cracks and mechanically stabilize the metal thin film 110, the metal thin film 110 is deposited on the surface of the metal nanomaterial/elastomer composite and then stretched in the longitudinal direction of the substrate to induce a mechanical crack shape in the metal thin film 110. By doing this, the ultra-thin patch-type skin strain sensor 10, which has a structure in which the plurality of metal thin film pieces 111 are spaced apart and arranged so that a crack gap 112 is formed, is completed.

Lastly, the ultra-thin patch-type skin strain sensor 10 with the crack formed is repeatedly stretched/relaxed to stabilize the interface shape when the crack is opened and closed, and through this, the operation characteristics of the ultra-thin patch-type skin strain sensor 10 induce stabilization.

Meanwhile, the operating principle of the ultra-thin patch type skin strain sensor 10 will be described in detail with reference to FIG. 6 as follows.

For reference, Figure 6 is a diagram to explain the operating principle of an ultra-thin patch-type skin strain sensor for early detection of infiltration. Specifically, (a) is a photograph of the manufactured skin strain sensor, and (b) is a schematic diagram of the operating principle of the skin strain sensor. , (c) is a micrograph of the surface of the sensor in the initial state (ε= 0%), and (d) is a micrograph of the surface of the skin strain sensor when 20% (ε= 20%) of strain is externally applied to the skin strain sensor. It represents.

The ultra-thin patch-type skin strain sensor 10 shown in Figure 6 was manufactured with a length of 65 mm, a width of 3 mm, and a thickness of 0.35 mm, as shown in Figure 6(a), and the structure of the sensor was manufactured in various arbitrary designs. It can be.

As shown in Figure 6(b), the ultra-thin patch-type skin strain sensor 10 according to the present invention maintains initial resistance ( R = R ₀ ) before strain is applied (ε = 0%), and then changes to strain. When applied (ε > 0%), it operates on the principle of detecting an increase in the resistance of the sensor ( R = R ₀ + Δ R ) induced by the opening of a crack formed in the metal thin film of the upper layer (11). In addition, when the applied strain is removed, the open metal thin film crack closes again, showing reversible characteristics in which the sensor's resistance returns to its initial state. At this time, the rate of change in resistance due to the applied strain (%) is measured and the sensitivity (GF, gauge factor) is measured according to Equation 1 below to perform the function of early detection of infiltration-inducing phenomenon.

(Equation 1)

In Equation 1 above,

Ro: initial resistance

△R: Change resistance difference (increased resistance)

Lo: initial length

△L: Change length difference (increased length)

ε: Input strain (%)

And the metal nanomaterial/elastomer conductive composite, which is the middle layer (12), plays two roles in improving the characteristics of the sensor as described below.

First, the intermediate layer of the metal nanomaterial/elastomer conductive composite that exists in the crack gap that opens according to the externally applied strain performs a conductive bridge function to electrically connect the metal island structure cracked by the mechanical crack, forming a metal thin film. It serves to improve the operating range of crack-based strain sensors.

Second, the surface roughness structure of the metal nanomaterial/elastomer conductive composite intermediate layer partially induces the mechanical crack shape of the metal thin film deposited on it to be a network shape instead of a general channel shape. It serves to improve the operating range of a strain sensor based on metal thin film cracks by ensuring a connection structure between metal islands.

Hereinafter, the performance of the strain sensor manufactured separately for each composite constituting the ultra-thin patch-type skin strain sensor 10 according to the present invention will be described.

Figure 7 compares the difference in representative characteristics of a typical metal thin film-based crack-based strain sensor and an AgNW/polymer composite-based strain sensor. As shown in Figure 7, the metal thin film crack-based strain sensor has the performance of high sensitivity (GF). However, its operating range (tensile range) is greatly limited, whereas strain sensors based on AgNW/polymer composites are capable of operating over a wide tensile range, but exhibit relatively low sensitivity.

For reference, the maximum strain operating range of the metal thin film crack-based strain sensor was about 1.3%, and the relative change rate of resistance at 1.3% strain was about 123.1%. On the other hand, in the case of the AgNW/polymer composite-based strain sensor, when the strain range was measured up to about 75%, the resistance change rate at 75% strain was about 6.2%.

Figure 8 is a scanning electron microscope showing the change in surface shape of a strain sensor based on a metal thin film/AgNW/Polymer composite according to sequentially increasing applied strain (0% → 20% → 40% → 60% → 80% → 100%). This is a scanning electron microscope image, and the magnification was measured at 500 times. For reference, in this case, platinum (Pt) was used as the metal thin film material. It was confirmed that mechanical cracks were generated on the electrode surface depending on the applied strain, and that the crack width increased as the applied strain increased. This change in the surface shape of the electrode is accompanied by a change in resistance, and operates as a strain sensor by inducing a change in resistance proportional to the change in shape of the electrode surface as the applied strain increases.

The sensitivity of a resistance-type strain sensor can be evaluated using the gauge factor (GF), and the GF value is the ratio of the resistance change rate (unit %, △R/Ro) according to the applied strain (unit %). It is defined as That is, in the response characteristics (relative resistance change rate compared to applied strain) results in FIG. 8, the slope of the graph represents the GF value. It was confirmed that the fabricated sensor showed stable response characteristics even to a large applied strain of 75%, which means that the relatively robust AgNW network under the metal thin film showed high resistance to deformation of the applied strain.

The response characteristics of the sensor can be divided into three linear sections, and the GF value analyzed in the first section (0 ∼ 40%) was about 29.3, and the linear regression curve (R ² ) at this time was It was about 0.94, and the GF value analyzed in the second section (40 ~ 60%) was about 126.5, and R ² at this time was It was about 0.961, and the GF value analyzed in the third section (60 to 75%) was about 493.2, and R ² at this time was about 0.946).

This phenomenon occurs when a crack induced in the metal thin film opens according to the applied strain, increasing the resistance of the sensor, but the metal island structure separated by the mechanical crack during tension is electrically connected by a network composed of AgNW, allowing a relatively wide tension range. This is because no electrical open occurred.

In addition, the increase in GF for each section due to stretching is believed to occur because the speed at which the contact points between AgNWs within the crack gap are reduced gradually accelerates during stretching.

Figure 9 compares representative sensor response characteristics of a strain sensor based on a metal thin film crack, a strain sensor based on an AgNW/polymer composite, and a strain sensor based on a metal thin film/AgNW/polymer composite. Strain sensors based on metal thin film cracks show a large rate of change in resistance even in low tension ranges as channel-shaped cracks open in response to tension, resulting in high sensitivity, but the operating range of the sensor is also greatly limited (the range of applied strain is limited). Unlike the strain sensor based on metal thin film cracks, the AgNW/polymer composite-based strain sensor was able to operate over a wide tensile range, but its sensitivity was limited because the resistance change rate (△R/Ro) was not large. In the case of a strain sensor based on a metal thin film/AgNW/polymer composite that combines a metal thin film and an AgNW/polymer composite in a hybrid form, the application of the AgNW/polymer composite induces a crack shape in the network structure in the metal thin film and at the same time, By providing an AgNW percolation network structure that acts as a conductive bridge in the crack gap, it exhibits relatively high sensitivity characteristics and the ability to operate over a wide tensile range.

Meanwhile, the early detection and notification system for infiltration using an ultra-thin patch-type skin strain sensor for early detection of infiltration according to the present invention (hereinafter referred to as the 'early infiltration detection system') will be described in detail with reference to FIGS. 10 to 12 below. Same as the contents of

The early infiltration detection system 100 according to the present invention includes an ultra-thin patch-type skin strain sensor 10, a detection unit 20, and a built-in control unit 30, as shown in FIG. 10.

The infiltration early detection system 100 detects the infiltration phenomenon at an early stage when the infiltration is about 0.5 to 1.0 cm in size by means of an ultra-thin patch-type skin strain sensor 10 attached to the patient's skin, and detects the phenomenon of infiltration early on, and detects the phenomenon of infiltration early on by medical staff, especially medical staff. Notification is sent to the nurse's terminal (S) using wireless communication, and the infiltration early detection system (100) installed next to the patient has a built-in function to continuously generate a warning sound from the alarm bell (40).

In order to facilitate attachment to the patient's skin, the infiltration early detection system 100 can be mounted on the patient's arm using a fixation belt 80, as shown in FIG. 11.

In the ultra-thin patch-type skin strain sensor 10, when the patient's skin swells due to an infiltration phenomenon, a plurality of metal thin film pieces 111 form crack gaps 112 at regular intervals, as shown in FIG. 4. This is a structure arranged to be spaced apart so that when the tissue causing the invasion swells, the metal thin film 110 formed by the crack gap 112 receives strain and expands, which causes a change in strain and thereby increases electrical resistance. It transitions into an increasing phenomenon.

Accordingly, strain is applied to the ultra-thin patch-type skin strain sensor 10, causing an increase in the resistance of the sensor. In other words, it performs the function of early detection of infiltration-inducing phenomenon by measuring the rate of change in resistance (sensitivity, GF, gauge factor) due to applied strain (%).

The detection unit 20 converts the increase in electrical resistance, that is, the strain rate of resistance due to the applied strain, into a voltage signal and transmits it to the built-in control unit 30.

Figure 12 is a circuit diagram showing the circuit configuration of the detection unit of the early detection system for invasion using an ultra-thin patch-type skin strain sensor for early detection of invasion according to the present invention. The detection unit 20 includes an operational amplifier U1, a capacitor C1, a capacitor C2, and a resistor. , R1, R2, R3, and R4.

Operational amplifier U1 amplifies and outputs the strain signal of the strain sensor 10, capacitor C1 and resistor R2 are provided between the first input terminal (non-inverting terminal) of operational amplifier U1, and capacitor C2 and resistor R4 are used for operation. It is provided between the second input terminal (inverting terminal) and the output terminal of amplifier U1. And, the resistor R1 is provided between the power source V+ and the strain sensor 10.

Explaining the operation sequence of the above-described detection unit 20, when a voltage is applied to V+ with the resistor R1 and the ultra-thin patch type skin strain sensor 10 connected in series, a potential difference occurs at node 1. Here, when resistance of the ultra-thin patch type skin strain sensor 10 occurs, the potential difference at node 1 changes accordingly. At this time, the change in potential difference is transmitted to the operational amplifier U1 (non-inverting terminal) through the filter of resistor R2 and capacitor C1, and then amplified and transmitted to the built-in control unit 30.

And the early invasion detection system 100 may further include an alarm bell 40, a battery unit 50, and an antenna 60, as shown in FIG. 10. The antenna 80 is preferably a built-in antenna.

The built-in control unit 30 is preferably a Bluetooth built-in control unit, and converts a voltage signal into a digital signal to wirelessly notify the medical staff of the state of infiltration, rings an alarm bell 40 according to the degree of infiltration, and has a battery unit 50. It allows the patient to move freely by eliminating unnecessary wires, such as wireless communication.

Therefore, the infiltration early detection system 100 according to the present invention sets the degree of swelling of the skin at the site of intravenous therapy when infiltration is induced using the setting switch 70 shown in FIG. 11 (for example, 0.5 to 1.0 cm) If it is determined that infiltration has been caused, the built-in control unit 30 notifies the medical staff through wireless communication, and then the alarm bell 40 continuously sounds a warning sound.

And Figure 13 is a photograph taken of an experiment to confirm the possibility of detecting skin swelling by demonstrating a balloon using the ultra-thin patch-type skin strain sensor for early detection of infiltration according to the present invention.

Figure 13(a) is a photograph of the experiment using a silver nanowire (AgNW)/Polymer composite-based strain sensor, and Figure 13(b) is a photograph of an experiment using a metal thin film/silver nanowire (AgNW)/Polymer composite sensor. This is a photo taken during the process.

As shown in Figure 13, the results of an experiment in which the strain conductive surface based on the silver nanowire (AgNW)/Polymer composite and the metal thin film/silver nanowire (AgNW)/Polymer composite were fixed in direct contact with the balloon were found in both cases. It was confirmed that the balloon exhibits relatively stable response characteristics to various shape changes, and it was confirmed that it would be possible to extract various parameters for the AC input signal.

Therefore, the present invention uses an ultra-thin patch-type skin strain sensor for early detection of infiltration to accurately detect infiltration early and prevent the occurrence of side effects due to infiltration in advance, while greatly reducing the workload of nurses while administering intravenous therapy. By monitoring frequently occurring infiltration phenomena in real time, infiltration-causing phenomena can be accurately detected early, and the infiltration-causing signal detected by the ultra-thin patch-type strain sensor-based infiltration early detection system can be transmitted to nurses and attending physicians through wireless communication. Notification via smartphone has the effect of allowing quick follow-up action.

In addition, the present invention uses an ultra-thin patch-type skin strain sensor for early detection of infiltration that can be used in combination with or as a replacement for the transparent dressing tape without the infiltration detection function used when performing existing intravenous therapy, making it easy to attach and wear to the skin of the body. This has the effect of not causing discomfort to the patient.

As described above, the ultra-thin patch-type skin strain sensor for early detection of infiltration and the early detection and notification system of infiltration using the same according to a preferred embodiment of the present invention have been described in detail with the accompanying drawings, but this is only an example. Those skilled in the art will be able to understand that various changes and modifications are possible without departing from the technical spirit of the invention.

100: Early detection system for infiltration using an ultra-thin patch-type skin strain sensor
10: Ultra-thin patch-type skin strain sensor for early detection of infiltration
11: upper layer 12: middle layer
13: lower layer
110: metal thin film 111: metal thin film piece
112: Crack gap 113: Metal nanomaterial
114: Elastomer
20: detection unit 30: built-in control unit
40: Alarm bell 50: Battery unit
60: Antenna 70: Setting switch
80: fixing belt 90: main board

Claims (7)

an upper layer (11) made of a metal thin film (110) with cracks formed;
An intermediate layer (12) made of a conductive composite in which metal nanomaterial (113) is embedded; and
a lower layer (13) made of elastic elastomer (114);
An ultra-thin patch-type skin strain sensor for early detection of invasion, characterized in that it consists of a structure comprising a.
According to claim 1,
The upper layer 11 is an ultra-thin thin film for early detection of invasion, characterized in that it is made of a metal thin film 110 arranged so that a crack gap 112 is formed between a plurality of metal thin film pieces 111. Patch-type skin strain sensor.
According to claim 2,
The intermediate layer (12) is an ultra-thin patch-type skin strain sensor for early detection of invasion, characterized in that the metal nano material (113) is uniformly dispersed and distributed within the elastomer (114).
According to claim 2,
The metal thin film piece 111 is an ultra-thin patch-type skin strain sensor for early detection of infiltration, characterized in that the material is selected from gold, silver, copper, aluminum, or platinum.
According to paragraph 1,
The metal nanomaterial 113 is an ultra-thin patch-type skin strain sensor for early detection of invasion, characterized in that the shape is selected from nano wire, nano particle, flake, or sheet.
According to paragraph 3,
The elastomer 114 is an ultra-thin patch type for early detection of invasion, characterized in that it is selected from polydimethylsiloxane, polybutadiene elastomer, silicone elastomer, or polyurethane. Skin strain sensor.
An ultra-thin patch-type skin strain sensor (10) for early detection of infiltration that detects infiltration of the patient's skin and generates applied strain;
A detection unit 20 that converts the strain of resistance due to the applied strain into a voltage signal and transmits it to the built-in control unit 30 below; and
A built-in control unit (30) that converts the voltage signal into a digital signal to wirelessly notify the medical staff of the state of infiltration and rings an alarm bell (40) according to the degree of infiltration;
An ultra-thin patch-type skin strain sensor for early detection of infiltration and an early detection and notification system of infiltration using the same.