Anti-occlusion agent for enteral administration catheters

Abstract

[Problem] To provide an anti-obstruction agent for enteral administration catheters that prevents contamination and blockage caused by oxidation of residual administered substances. [Solution] The anti-obstruction agent for enteral administration catheters is a gel-like substance characterized by being a hydrogel using water-soluble polysaccharides and / or water-soluble proteins. To prevent blockage due to oxidative contamination in the enteral administration catheter, the anti-obstruction agent for enteral administration catheters is filled into and retained in the enteral administration catheter to prevent blockage. [Selected Figure] None

Description

Technical Field

[0001] The present invention relates to a transcatheter administration catheter that maintains a clean environment inside the catheter and effectively prevents catheter occlusion. Method to prevent blockage It relates to.

[0002] Conventionally, as a method of administering substances such as nutrients and drugs to the human body, enteral nutrition methods such as nasally, orally, or percutaneously inserting a catheter into the digestive tract and administering it transcatheterically are common. The catheter used in this way is here referred to as a transcatheter administration catheter, and hereinafter simply referred to as a catheter. The catheter becomes contaminated over time, and the contamination gradually accumulates and solidifies inside the catheter, so the catheter lumen becomes narrow and occluded. The reason for the contamination is that the catheter lumen is in an environment where it is prone to oxidation. The lumen of an actually occluded catheter shows a pH of about 5.

[0003] The following reasons can be considered for the oxidation inside the catheter. One is the oxidation due to the remaining nutrient agent in the catheter coming into contact with air. The second is the oxidation during the growth process of viruses and bacteria that enter the catheter from the hands of the person involved in the injection of the administered substance or the tools used for the injection. The third is the oxidation caused by the mucus from the digestive tract at the catheter placement site flowing into the catheter under the influence of coughing, body movement, increased abdominal pressure caused by body position, and drainage effect. The mucus in the digestive tract has a pH of 2 when placed in the stomach and a pH of 5 to 6.5 in the small intestine.

[0004] Of course, even if the inside of the catheter is contaminated by oxidation, as long as it is not occluded, the administered substance can be injected. However, leaving the contamination untreated causes the problem that the administered substance passes through an unhygienic route. That is, although the catheter is the route through which the administered substance is administered, leaving the contamination untreated causes problems in terms of hygiene and also has the problem of occlusion due to the accumulation of contamination.

Prior Art Documents

Non-Patent Documents

[0005] [Non-Patent Document 1] Mana Doi, et al., "A Survey of the Current Status of Gastrostomy Catheter Management in Hospitals and Long-Term Care Facilities in Japan," JSPEN Vol. 2, No. 3, pp. 186-195, 2020.

[0006] [Non-Patent Document 2] Yuko Tabuchi, et al., "Basic and Clinical Studies on the Prevention of Enteral Nutrition Tube Obstruction with 1% Sodium Bicarbonate Solution," Parenteral and Enteral Nutrition Vol. 26 No. 4 2011, pp. 51(1119)–55(1123).

[0007] [Non-Patent Document 3] Guidelines for Parenteral and Enteral Nutrition for Allied Health Professionals, Japanese Society for Parenteral and Enteral Nutrition, July 2000, Nankodo Publishing Co., Ltd. [Overview of the project] [Problems that the invention aims to solve]

[0008] As described in Non-Patent Documents 1 and 2 above, it is considered effective to inject a 1% diluted sodium bicarbonate solution or a 10% diluted grain vinegar solution into the catheter to prevent occlusion caused by contamination of the catheter lumen. This is because sodium bicarbonate keeps the inside of the catheter alkaline, which prevents oxidation, and grain vinegar has excellent bacteriostatic properties, preventing oxidation caused by bacterial growth. Non-Patent Document 3 also recommends rinsing the catheter with 20 ml of water each time after injection.

[0009] Conventionally, when no drug is being administered, the catheter is filled with an aqueous solution such as sodium bicarbonate solution or grain vinegar solution. However, because these aqueous solutions are highly fluid, some of the solution leaks into the patient's body between the time it is injected into the catheter and the time the injection port is closed, leaving a space on the injection port side of the catheter that is not filled with the solution, and thus the entire catheter lumen cannot be filled. As a result, there is a problem in which contamination progresses in the space that is not filled with the solution. Furthermore, if the method of closing the injection port involves bending one end of the catheter on the injection port side, that part becomes prone to breakage, leading to a shortened catheter lifespan. In addition, increased abdominal pressure due to coughing or postural drainage can cause the patient's bodily fluids to push up and backflow the aqueous solution inside the catheter, resulting in contamination of the catheter with bodily fluids.

[0010] The inventors of this invention have diligently studied effective methods for preventing catheter contamination and occlusion, and have found that a gel-like substance can maintain a clean environment inside the catheter and can be effectively used as an anti-occlusion agent.

[0011] This invention is based on this finding and aims to provide a catheter occlusion prevention agent that maintains a clean environment inside the catheter and effectively prevents catheter occlusion. [Means for solving the problem]

[0012] To achieve the above objectives The present invention relates to a method for preventing occlusion of an enteral administration catheter, Prepare an anti-occlusion agent consisting of a hydrogel containing 0.6 to 1.2 g of water-soluble polymer per 325 g of water by weight. Next, the anti-occlusion agent is filled into the enteral administration catheter while no substance has been administered into it. Next, by closing the injection port of the connector portion at the end of the enteral administration catheter, a closed environment is created inside the enteral administration catheter. In this state, the anti-obstruction agent is retained in the enteral administration catheter until the next dose is administered. A method for preventing blockage of an enteral administration catheter, characterized by opening the injection port of the connector portion at the end of the enteral administration catheter when administering the next dose, and administering the dose into the enteral administration catheter, thereby expelling the blockage prevention agent into the body. This was the gist of it.

[0013] According to this invention, the enteral administration catheter occlusion prevention agent is gel-like and has low fluidity, so after being injected into the catheter, it can remain inside the catheter even if the injection port is not immediately closed, and will not flow into the patient's body until pressure is applied for the next administration. Therefore, the entire inside of the catheter can be filled with the enteral administration catheter occlusion prevention agent. Furthermore, even if the patient's bodily fluids attempt to flow back into the catheter, the occlusion prevention agent prevents the inflow of bodily fluids into the catheter.

[0014] In the invention described in claim 2, A method for preventing occlusion of an enteral catheter according to claim 1, wherein a gel-like substance characterized in that the water-soluble polymers are xanthan gum and locust bean gum is used as an occlusion prevention agent. This was the gist of it.

Advantages of the Invention

[0015] For the transcatheter of the present invention Regarding methods for preventing blockage, Prepare an anti-blocking agent made of a gel-like substance in advance, fill it into the catheter without the administration substance, and maintain a clean environment inside the catheter, thereby effectively preventing its blockage.

Brief Description of the Drawings

[0016] [Figure 1] Schematic diagram of the device for measuring the flow-down amount. [Figure 2] Graph showing the flow-down amount measurement results. [Figure 3] Schematic diagram of the device for the occlusion comparison test. [Figure 4] Graph showing the occlusion comparison test results.

Best Mode for Carrying Out the Invention

[0017] Hereinafter, the transcatheter of the present invention Blockage prevention method will be described in detail. The anti-blocking agent of the present invention effectively prevents the blockage of gastrostomy or enterostomy added to the human body percutaneously, or catheters inserted into the digestive tract nasally or orally, and exhibits sufficient effects on catheters made of generally used silicone rubber, polyurethane, polytetrafluoroethylene (PTFE), polyethylene, etc. Further, by changing the hardness of the gel-like substance of the present invention, it can be applied to catheters of any thickness and length.

[0018] The present invention In, The anti-blocking agent is filled in the state where no administration substance is administered into the catheter. To the catheters of the transcatheter administration subjects, administration substances such as nutritional agents and drugs are administered multiple times a day. After the administration substance is administered, the catheter is washed with water and placed in a state where the injection port is closed until the next administration. The anti-blocking agent of the present invention is filled into the catheter washed with water after the administration substance is administered, and can stay in the catheter by closing the injection port.

[0019] The catheter has an open tip that is placed inside the body. The injection end, into which the occlusion-preventing agent of the present invention is filled, is outside the body and has a connector portion with a lid. By opening the lid of this connector portion, filling the catheter with the occlusion-preventing agent using an injector, and closing the lid, a closed environment is created inside the catheter, and the occlusion-preventing agent remains inside the catheter.

[0020] The occlusion prevention agent that is filled into and retained in the catheter will be used for subsequent administration of nutritional supplements or medications. Therefore, it will be excreted from the body along with the administered substance. This occurs at a frequency of once or more per day. By repeatedly filling, retaining, and draining the anti-occlusion agent, the inside of the catheter remains clean. This will be maintained by the environment, and catheter blockage will be effectively prevented.

[0021] This invention In, The gel-like substance constituting the occlusion prevention agent is preferably a hydrogel made of a water-soluble polymer with a three-dimensional structure containing water. For example, when an oily gel is used, the polymer material constituting the catheter swells, and oil can enter between its molecules, potentially softening the catheter or reducing its strength. In contrast, hydrogels have the advantage of not affecting the strength of the catheter.

[0022] This invention In, The anti-occlusion agent is a hydrogel, a gel structure formed by water entering a three-dimensional network structure of water-soluble polymers. The hardness and fluidity of this hydrogel depend largely on the amount of water contained within the three-dimensional network structure.

[0023] This invention In,When preparing a hydrogel as an anti-obstruction agent, it is preferable that the amount of water is 464g to 650g by weight per 1g of the water-soluble polymer. If the amount of water is less than 463g, the hydrogel will harden and will not be able to obtain sufficient fluidity, requiring strong force to be pushed in for filling and retention in the catheter. However, gastrostomy catheters come in large diameter sizes such as 24 French (outer diameter 8cm), and even a hard gel can be easily filled and retained in such catheters. For situations with a large diameter and exposure to stomach acid, filling and retaining a hard hydrogel is suitable.

[0024] On the other hand, when the amount of water exceeds 650g, it becomes a highly fluid hydrogel, which has the advantage of being easy to fill and retain in thin catheters of 6 French or less (outer diameter 2mm) without requiring strong pushing force. However, when used in catheters with a diameter of 7 French or more, air bubbles are more likely to form, creating areas where the hydrogel cannot cover the contaminants, leading to the problem of oxidation of the contaminants in those areas. Thus, by adjusting the amount of water, the hardness of the hydrogel can be changed, and it is possible to create an occlusion prevention agent that is easy to fill and retain in catheters of various sizes.

[0025] Furthermore, hydrogels of various degrees of firmness can be produced not only by the amount of water but also by the combination of water-soluble polymers that make up the hydrogel, making it possible to adjust the firmness to suit the catheter and the individual's physical condition. In the case of the aforementioned gastrostomy catheter, a nutritional supplement that is closer to solid than liquid is sometimes desired to prevent the exacerbation of reflux esophagitis and leakage of gastric contents from the catheter insertion site. Since the obstruction prevention agent of the present invention is also taken into the stomach, the desired firmness can be achieved by preparing it with a water content of 464 or less.

[0026] Any type of drinking water is acceptable. While alkaline ionized water is not recommended for patients with renal dysfunction or potassium excretion disorders, it is considered suitable for the preparation of the occlusion prevention agent of this invention because it is thought to resist the oxidation of nutritional supplements within the catheter.

[0027] This invention In, closed The anti-occlusive agent is more preferably a hydrogel made of at least one selected from water-soluble polysaccharides and / or water-soluble proteins. Examples of water-soluble polysaccharides include carrageenan, agar, Inagel, Farcerelan, alginates, chymiloid, chymica algin, gum arabic, tragacanth gum, karaya gum, cassia gum, psyllium seed gum, galactomannan (fenucleik gum), locust bean gum (carob bean gum), guar gum, Tara gum, pectin, Examples include arabinogalactan, xanthan gum, ultraxanthan gum, gellan gum, curdlan, gellan gum, natto gum, microcrystalline cellulose, hydroxypropyl cellulose, carboxymethylcellulose, microfibrous cellulose, and methylcellulose. While only one type of water-soluble polysaccharide may be used, a combination of two or three types can also be employed.

[0028] Possible combinations include xanthan gum and locust bean gum, xanthan gum and agar, and xanthan gum and gelatin. More preferably, xanthan gum and locust bean gum are used in a weight ratio of 2:8 to 7:3.

[0029] Examples of water-soluble proteins include gelatin, casein, albumin, and collagen. Water-soluble proteins can be used individually or in combination.

[0030] Examples of combinations of water-soluble polysaccharides and / or water-soluble proteins include xanthan gum and gelatin.

[0031] As mentioned earlier, agar is rich in fiber and can be expected to improve constipation. In addition, it is desirable to add water-soluble dietary fiber such as inulin or guar gum in addition to water-soluble polysaccharides and / or water-soluble proteins, as these can also be expected to improve constipation.

[0032] In cases of hyponatremia, the addition of sodium bicarbonate is effective.

[0033] For pediatric use, it's possible to add a preferred scent or coloring agent such as beta-carotene each time it's used, resulting in a pink color. If the catheter is light-transmitting, even a slight coloring will make the catheter's appearance appear cleaner.

[0034] This invention In, In addition to preventing catheter blockage, the blockage prevention agent can also be formulated to include butterfly pea tea, a type of herbal tea. In this case, the blockage prevention agent will be colored blue. By including herbal tea, anti-aging effects can be expected, making it a substance that is desirable not only for preventing catheter blockage but also for ingestion. Furthermore, the coloring makes it easier to distinguish the agent from other injectable substances.

[0035] Furthermore, the present invention In, If the blockage prevention agent is packaged in small 5ml individual packets, it can be easily carried with people who receive enteral nutrition when they go out, and the blockage prevention agent can be refilled wherever they are.

[0036] Furthermore, the present invention In, By sterilizing the anti-obstructive agent using methods such as ultraviolet irradiation, it can be used without affecting the patient's health, even in cases of immunocompromised digestive tract infections.

[0037] This invention In, The anti-occlusion agent can be used as follows: Before filling with the anti-occlusion agent, the inside of the catheter is rinsed with water. Then, the anti-occlusion agent is filled into the catheter using an injector. The amount of anti-occlusion agent used varies depending on the diameter and length of the catheter, but is approximately 3 to 5 ml. Because the anti-occlusion agent has lower fluidity than aqueous solutions, it can be filled and retained in the catheter without bending.

[0038] The anti-occlusion agent that fills and remains in the catheter covers the remaining administered substance, preventing oxidation and solidification due to exposure to air. Furthermore, the water-retaining properties of the hydrogel used as the anti-occlusion agent prevent the covered substance from solidifying. Therefore, the remaining substance in the catheter remains soft and easily detached, effectively preventing occlusion by preventing the accumulation of contamination in the catheter. [Examples]

[0039] The present invention will be described in more detail below based on examples. The preparation of a test sample (example) used for measuring the flow rate and a test sample (comparative example) for comparison therewith will be described in the following section. (Example 1)

[0040] 0.3g of xanthan gum (Unitech Foods Co., Ltd., Xanthan Gum Granules, Clear Type) and 0.3g of locust bean gum (Unitech Foods Co., Ltd., Locust Bean Gum) were placed in a bowl and mixed uniformly. 325g of alkaline ionized water (SOC Co., Ltd., Hot Spring Water 99) heated to approximately 90°C was added and stirred to prepare a sol. The resulting sol was allowed to stand at room temperature for 2 hours and allowed to cool naturally to gel, obtaining a test sample (Example 1).

[0041] (Example 2) 0.15 g of xanthan gum and 0.15 g of locust bean gum used in Example 1 were placed in a bowl and mixed uniformly. 325 g of alkaline ionized water used in Example 1, heated to approximately 90°C, was added and stirred to prepare a sol. The resulting sol was allowed to stand at room temperature for 2 hours and allowed to cool naturally to gel, obtaining a test sample (Example 2).

[0042] (Example 3) 0.6 g of xanthan gum and 0.6 g of locust bean gum used in Example 1 were placed in a bowl and mixed uniformly. 325 g of alkaline ionized water used in Example 1, heated to approximately 90°C, was added and stirred to prepare a sol. The resulting sol was allowed to stand at room temperature for 2 hours and allowed to cool naturally to gel, obtaining a test sample (Example 3).

[0043] (Example 4) 0.6 g of locust bean gum used in Example 1 was placed in a bowl, and 325 g of alkaline ionized water used in Example 1, heated to approximately 90°C, was added and stirred to prepare a sol. The resulting sol was allowed to stand at room temperature for 2 hours and allowed to cool naturally to gel, obtaining a test sample (Example 4).

[0044] (Example 5) The xanthan gum 0.6 g used in Example 1 was prepared and gelled in the same manner as in Example 4 to obtain a test sample (Example 5).

[0045] (Example 6) 0.3 g of xanthan gum used in Example 1 and 0.3 g of UNet W-D29 (UNet W-D29, Unitech Foods Co., Ltd.) were placed in a bowl and mixed uniformly. 325 g of alkaline ionized water used in Example 1, heated to approximately 90°C, was added and stirred to prepare a sol. The resulting sol was allowed to stand at room temperature for 2 hours and allowed to cool naturally to gel, obtaining a test sample (Example 6).

[0046] (Example 7) 0.3 g of xanthan gum used in Example 1 was placed in a bowl. 2.6 g of agar (Ina Foods Co., Ltd.), calculated according to the amount of water according to the attached instructions, was placed in a pot containing 325 g of alkaline ionized water used in Example 1. The pot was heated and brought to a boil, and the agar was dissolved while stirring for 2 minutes. Then, it was transferred to the bowl containing the xanthan gum and stirred further to prepare a sol. The resulting sol was left to stand at room temperature for 2 hours to cool naturally, and then refrigerated for 1 hour to gel, obtaining a test sample (Example 7).

[0047] (Example 8) Place 0.3g of xanthan gum used in Example 1 in a bowl, and dissolve 6.5g of gelatin (Morinaga & Co., Ltd.), calculated according to the amount of water according to the attached instructions, in 325g of alkaline ionized water used in Example 1, which had been preheated to over 80°C. Add the resulting solution to the bowl with 265g of alkaline ionized water and stir to prepare a sol. Next, refrigerate this to gel, and obtain a test sample (Example 8).

[0048] (Comparative Example 1) 1 g of baking soda (Taiyo Yushi Co., Ltd., Pax Baking Soda F) was mixed and dissolved in 100 g of the alkaline ionized water used in Example 1 to prepare a 1% baking soda solution (Comparative Example 1).

[0049] (Comparative Example 2) 10g of grain vinegar (Tamanoi Healthy Grain Vinegar, Tamanoi Co., Ltd.) was mixed and dissolved with 100g of alkaline ionized water used in Example 1 to prepare a 10% grain vinegar solution (Comparative Example 2).

[0050] Examples 1 to 8 and Comparative Examples 1 and 2 are shown in Table 1. [Table 1]

[0051] (Measurement of flow rate) For each sample in Examples 1 to 8 and Comparative Examples 1 and 2, the flow rate of each sample was measured using the apparatus shown in Figure 1. As shown in Figure 1, the apparatus 1 consists of a straw 3 (PET bottle straw Feeling MADE IN INDONESIA, imported and distributed by Yamato Bussan Co., Ltd., made of polypropylene, approximately 6 mm in diameter x 25 cm) positioned at a 45-degree inclination angle, a syringe 2 (Top Syringe, medical device registration number 13BIX00085000021) into which the sample S is placed in the straw 3, a receiving tray 4 to receive the sample S flowing down from the straw 3, and a scale 5 for measuring the weight of the receiving tray 4 and the sample S. To measure the flow rate, first, each sample was drawn up to the 1 ml mark using syringe 2, and then the drawn-up sample was placed into the straw 3. The weight of each sample drawn up with syringe 2 is shown in Table 2. The sample S that entered the straw 3 would fall into the receiving tray 4 from the bottom of the straw 3 due to its own weight. Its weight was measured using scale 5. Each sample took approximately 0.3 seconds to fill into the straw, and the amount of liquid that flowed down was measured 30 seconds after filling. The weight (amount of liquid that flowed down) of sample S after it fell into straw 3 is shown in Table 2 and Figure 2. The amount of liquid that flowed down was evaluated based on the degree to which samples with low fluidity were difficult to fall out of the straw and samples with high fluidity were easy to fall out. The environment during the test was room temperature 22.7°C and humidity 52%.

[0052] [Table 2] As shown in Table 2 and Figure 2, the gels of Examples 2, 4, and 5 had high fluidity and were easy to fill and retain in thin catheters of 6 French diameter (2 mm outer diameter) or less, but it was confirmed that air bubbles were easily introduced in catheters of 7 French diameter (2.3 mm outer diameter) or larger. Even if care is taken to prevent air bubbles from entering when drawing up into the syringe, catheters made of materials such as silicone rubber, polyurethane, polytetrafluoroethylene (PTFE), and polyethylene may undergo slight deformation of the injection port during use, making it difficult to prevent air from entering through the resulting gaps.

[0053] Example 7 resulted in the firmest gel, which did not flow through straw 3. Drawing it up with syringe 2 and dripping it into straw 3 was also difficult. Examples 3 and 8 flowed down but were firm, and, similar to Example 7, required strong force to fill and retain in a catheter thinner than straw 3, creating pressure inside the catheter. While this pressure has the advantage of potentially releasing occlusion in blocked catheters, it is not easy for daily injection procedures, posing a challenge in terms of ease of use.

[0054] Furthermore, the agar used in Example 7 is prone to syneresis (water separation) in environments above 10°C after gelation, and it is preferable to use it at room temperature or below. As syneresis progresses, the gel breaks down and becomes a highly fluid aqueous solution, so care must be taken with the storage temperature.

[0055] The gels in Examples 1 and 6 are easy to fill and retain in a catheter, and are less prone to air bubbles. Moreover, unless squeezed out, they remain filled and retained in the catheter, making them resistant to reflux from the digestive tract. UNet W-D29, used in Example 6, was recently marketed as a substitute for locust bean gum, which has become very expensive. However, it is not possible to achieve the same results with locust bean gum. Easy to peel off It is less likely to form a gel, and in terms of stain resistance, it is slightly inferior to Example 1.

[0056] Examples 1 to 8 demonstrate that hydrogels of varying degrees of firmness can be produced depending on the combination of water-soluble polysaccharides and / or water-soluble proteins, as well as the amount of water used. Furthermore, they possess different properties, such as ease of use and storage, and antioxidant properties. These occlusion prevention agents can be adjusted and prepared according to the diameter, length, and material of the catheter to be used. Although there are some differences in their effectiveness in preventing catheter fouling, all of them can be used effectively to prevent occlusion.

[0057] In Comparative Examples 1 and 2, almost all of the fluid flowed down in an instant. While it was easy to insert the fluid into the catheter without applying pressure, almost the entire amount passed through the catheter immediately and reached the digestive tract, making it difficult to fill and retain the fluid. Any remaining nutritional supplement oxidized in the water-free catheter, leading to blockage over time.

[0058] (Obstruction prevention performance evaluation test) Next, the catheter occlusion prevention performance was evaluated for each sample from Example 1, Comparative Example 1, and Comparative Example 2, as well as for five types of samples including alkaline ionized water and tap water. The apparatus shown in Figure 3 was used for the tests. The environment during the test period (May 14 to December 17) was indoors, with a room temperature of approximately 19°C to 26.7°C and a humidity of 44% to 60%.

[0059] As shown in Figure 3, five catheters (Nipro Nelaton catheter 8Fr. outer diameter 2.67 mm, 33 cm, closed tip, 2 holes, product number 23-420NNT-082) 13, filled with and containing a nutritional supplement (high-nutrient liquid food Crimil CZ-Hi, manufactured by Clinico Co., Ltd., Morinaga Milk Industry Group's Clinical Nutrition Division), were placed on a 45-degree inclined surface. The weight of each catheter was approximately 1.33 g, with slight variations. Next, each sample was washed with 5 ml of tap water, and then filled and contained in each catheter 13 using a syringe 12 for about 15 minutes, after which the nutritional supplement was injected again. Each sample S was discharged into a receiving tray 14 upon injection of the nutritional supplement. This procedure was repeated daily. The filling speed into the catheters was set to approximately 0.4 seconds. To fill and retain the catheter, approximately 2 ml each of the nutritional supplement and each sample was required for an 8-French, 33 cm catheter. Additionally, the 2 cm end of the catheter was bent with clip 16 to create a closed environment, allowing for filling and retention without introducing air bubbles.

[0060] The test results are shown in Figure 4. Except for the sample from Example 1, all samples became blocked, although at different times. In this test, blockage refers to a state where injection is impossible, as even when strong force is applied to the plunger P when attempting to inject with the injector (a syringe was used in the test) 12, the plunger cannot be pushed. In Figure 4, Example 1 is indicated by ○1, Comparative Example 1 by ○2, Comparative Example 2 by ○3, alkaline ionized water by ○4, and tap water by ○5.

[0061] The measured weight increased in proportion to the contamination. The weight may decrease again after the increase, but this is because solidified contamination may detach and be pushed out during injection, resulting in a decrease in weight in the measurement the following day.

[0062] The first sample to become blocked was alkaline ionized water. It was natural hot spring water and did not contain chlorine. Its pH was above 9, and if high-pH water could be effective in preventing fouling and blockage in the oxidative environment of the catheter, then aqueous solutions made with baking soda or grain vinegar, and consequently the gel made with water-soluble polysaccharides and / or water-soluble proteins, would be unnecessary. However, no effect on preventing fouling was confirmed within the catheter, and although the contamination fluctuated, it became blocked on the 35th day. This confirmed that pH control within the catheter is ineffective in preventing fouling and blockage.

[0063] Subsequently, on day 43, the sample of Comparative Example 1 became occluded. The decrease in weight at the time of occlusion was due to the fact that after confirming occlusion by connecting syringe 12 to catheter 13 and strongly pressing the plunger P, approximately 1 cm of solidified contamination from within catheter 13 adhered to the tip of syringe 12 and was removed from within catheter 13, resulting in a decrease in weight. Similar to the alkaline ionized water sample, the results showed that pH control within the catheter was ineffective in preventing occlusion.

[0064] On day 58, the tap water sample became blocked. While the tap water maintained a residual chlorine concentration of 0.1 mg / L, this may have had a slight effect in preventing catheter contamination compared to the sample in Comparative Example 1. However, it is not sufficient to prevent blockage.

[0065] The catheter containing the sample from Comparative Example 2 actually became occluded on the 12th day. However, by persistently pushing the plunger P with considerable force, the occlusion was released, and the test was continued. Except for the tip, there was a period during which the catheter remained in the cleanest state among all the samples. Only the catheter tip was contaminated, as had been observed from the beginning of the test. After the test was resumed, it maintained a relatively clean appearance for a while, but over time, contamination continued to increase slowly in areas other than the tip. Although the weight fluctuated as contamination was washed away during rinsing and nutritional supplement injection, it became occluded again on the 72nd day. This occlusion could not be released even by continuously pushing the plunger with strong force, as had happened on the 12th day. The injection end was less prone to contamination because the syringe tip came into contact with the nutritional supplement residue each time it was injected. On the other hand, the tip of the catheter only had the nutritional supplement, 5 ml of tap water used for rinsing, and the sample from Comparative Example 2 flowing through and accumulating, making it impossible to clean the accumulation of contamination at the tip. In Comparative Example 2, although the catheter (excluding the tip) was cleaned for a certain period, the results showed that occlusion could not be prevented.

[0066] The sample in Example 1 maintained a weight of approximately 1.5g and, although contamination was observed, did not become blocked. Even on day 217 (December 17th), it remained unblocked, and the test was terminated without blockage. What distinguished the catheter used in Example 1 from the others was that most of the contamination within the catheter was washed away during rinsing with tap water the following day. At that time, the contamination adhering to the catheter was soft and easily peeled off the inner surface of the catheter when pressed with a fingertip. The contamination in the other catheters, similarly, was sticky when pressed with a fingertip. Difficult to peel off The contamination was not washed away by rinsing with tap water. Regarding the cause of catheter contamination, it was stated that the contamination gradually solidifies within the catheter, causing the catheter lumen to narrow and become blocked. However, it was confirmed that if the solidification of the contamination can be prevented, blockage will not occur, and that only the occlusion prevention agent of the present invention can achieve this.

[0067] Even if the sample in Comparative Example 2 is effective in preventing catheter fouling and blockage, the difference in pH may irritate the mucous membrane of the digestive tract other than the stomach. Although the pH is similar when injected into the stomach, it is not desirable to inject an acidic substance into the stomach, especially when antacids are being taken for gastroesophageal reflux disease. The sample in Comparative Example 1 has a high pH, ​​which differs from the mucosal environment of the digestive tract. Furthermore, because it contains sodium, it is not recommended in cases of fluid restriction or heart or kidney disease. The sample in Example 1 is superior to the conventional samples in Comparative Example 1 and Comparative Example 2 in that the amount used to fill the catheter is sufficient to effectively prevent fouling and blockage, the pH is determined by water and remains neutral to slightly alkaline, and there are no concerns about its effects on the body.

[0068] Next, the safety of the occlusion prevention agent of the present invention was evaluated. For comparison with the sample of Example 1, a nutritional supplement (Morinaga High Nutrition Liquid Food Creamil CZ-Hi, Morinaga Milk Industry Group Clinical Nutrition Division, Clinico Co., Ltd.) was used as a test sample (sample of Comparative Example 3). 60g each of the samples from Example 1 and Comparative Example 3 were drawn up with 5ml of air into two sterile 30ml syringes (Top Syringe, Medical Device Registration Number 1381X00085000021, Top Co., Ltd.), and after standing at room temperature for two weeks, they were submitted for food microbiology testing. The samples were submitted to the Genetic Hygiene Testing Section, Analysis and Testing Department, Hiyoshi Co., Ltd. (908 Kitano-cho, Omihachiman City, Shiga Prefecture), a registered testing institution under the Food Sanitation Act and registered with the Shiga Prefectural Hygiene Inspection Service. The test results are shown in Table 3.

[0069] [Table 3]

[0070] The increase in bacterial count in Example 1 was 6.9 × 10⁶, which was lower than the 6.0 × 10⁶ in Comparative Example 3. In catheters, which are the route of administration of the drug, oxidative contamination due to residual drug can become a breeding ground for bacterial growth. Therefore, it can be said that filling and retaining the catheter with the occlusion prevention agent is more effective in maintaining cleanliness within the catheter. It is thought that filling and retaining the catheter with the occlusion prevention agent after drug injection will enable the establishment of a cleaner administration route than ever before. [Industrial applicability]

[0071] This invention can be effectively used to prevent obstruction of gastrostomies and jejunostomies implanted percutaneously in the human body, or enteral feeding catheters inserted into the digestive tract via nasal or oral routes. [Explanation of Symbols]

[0072] P pusher S Sample 2 syringes 3 straws 4. 14. Drip tray 5, 15 scale S2 Samples and Nutritional Supplements 12 syringes 13 Catheter 14. Drip tray

Claims

1. A method for preventing occlusion of an enteral administration catheter, An anti-occlusion agent consisting of a hydrogel containing 0.6 to 1.2 g of water-soluble polymer per 325 g of water by weight is prepared. Next, the anti-occlusion agent is filled into the enteral administration catheter while no substance has been administered into it. Next, by closing the injection port of the connector portion at the end of the enteral administration catheter, a closed environment is created inside the enteral administration catheter. In this state, the anti-obstruction agent is retained in the enteral administration catheter until the next dose is administered. A method for preventing blockage of an enteral administration catheter, characterized by opening the injection port of the connector portion at the end of the enteral administration catheter when administering the next substance, and administering the substance into the enteral administration catheter, thereby causing the blockage prevention agent to be discharged into the body.

2. The method for preventing occlusion of an enteral administration catheter according to Claim 1, characterized in that the water-soluble polymer is xanthan gum and locust bean gum.

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