Intelligent monitoring and repairing system for gastrointestinal anastomosis

Abstract

This invention discloses an intelligent monitoring and repair system for gastrointestinal anastomoses, relating to the fields of medical devices and biomedical engineering technology. The system includes a bioresponsive sealing adhesive, an intelligent drainage catheter, and an external intelligent terminal. The sealing adhesive covers the surface of the anastomosis and releases colorimetric and fluorescent signals under the action of gastric, intestinal, or pancreatic juice. The intelligent drainage catheter has a main drainage chamber, a pneumatic monitoring chamber, an optical conduction channel, and a perfusion chamber, with an anti-adhesion cage at its tip. The external intelligent terminal is used for optical detection and vacuum attenuation determination. This system can achieve local sealing of the anastomosis, identification of abnormal signals, and monitoring of catheter status.

Description

Technical Field

[0001] This invention relates to the field of medical devices and biomedical engineering technology, specifically to an intelligent monitoring and repair system for gastrointestinal anastomosis. Background Technology

[0002] Anastomotic leakage of the gastrointestinal tract is one of the more serious complications after gastrointestinal surgery, which can lead to re-intervention, prolonged hospital stay, increased readmission rate, and even increased risk of death. Related reviews also pointed out that the reported incidence of anastomotic leakage in colorectal surgery varies greatly, but it has always been a key issue affecting postoperative recovery and prognosis. Therefore, early identification is of great clinical significance.

[0003] Current methods for identifying anastomotic leaks largely rely on clinical symptoms, imaging examinations, or changes in postoperative drainage fluid parameters. These methods often suffer from issues such as delayed detection, insufficient continuous monitoring capabilities, and a lack of standardized thresholds and procedures. A systematic review of perianastomotic pH monitoring also points out that while these methods have the potential for early detection, current evidence still lacks standardized thresholds and protocols.

[0004] Therefore, there is an urgent need for an intelligent monitoring and repair system for gastrointestinal anastomosis that can take into account local closure, continuous monitoring, signal differentiation and recognition, and pathway linkage, so as to improve the early identification capability and system integration of postoperative anastomotic abnormalities.

[0005] A search revealed a Chinese patent document that discloses a rectal anastomosis protection and drainage device [Application No.: 202010270840.5, Publication No.: CN111569163B], which includes a connecting part, a blocking part, and a drainage part. The connecting part is used to connect to the intestinal incision site, the blocking part is used to block the intestinal contents, and the drainage part includes a drainage tube, a negative pressure drainage bag, and a drainage implant, used to drain the mixture inside the intestine. At the same time, it also discloses a design in which the reactive plug or reactive strip can dissolve in intestinal fluid to achieve local isolation and subsequent decomposition and discharge. While the comparative patent achieves similar objectives of protecting the anastomosis, isolating intestinal fluid, and draining, featuring a coordinated arrangement of connecting, blocking, and draining parts, and a local reactive structure that changes with the action of intestinal fluid, this invention goes beyond anastomosis protection and drainage. It further incorporates an integrated system structure including a bioresponsive sealing adhesive, a multi-lumen intelligent drainage catheter, an optical conduction channel, a pneumatic monitoring cavity, and an external intelligent terminal. This system can distinguish and identify signals related to gastric fluid and trypsin-rich fluids, and outputs catheter blockage, patency, and tissue encapsulation status using a vacuum attenuation method. The aforementioned local environmental response signal release, dual-channel optical monitoring, and external linkage monitoring structure are not present in the comparative patent. Summary of the Invention

[0006] In view of the problems existing in the prior art, the purpose of this invention is to provide an intelligent monitoring and repair system for gastrointestinal anastomosis.

[0007] A smart monitoring and repair system for gastrointestinal anastomosis, characterized in that it includes a bioresponsive sealing adhesive applied to the surface of the gastrointestinal anastomosis, a smart drainage catheter disposed near the gastrointestinal anastomosis, and an external smart terminal connected to the external end of the smart drainage catheter. The intelligent drainage catheter includes a main drainage chamber, a pneumatic monitoring chamber, an optical transmission channel, and an infusion chamber. The head end of the intelligent drainage catheter is provided with an anti-adhesion cage. The aforementioned external intelligent terminal includes a negative pressure generating unit, a pressure sensing unit, a multi-band light source, a multi-band optical detection unit, and a central processing unit; The pressure sensing unit is connected to the pneumatic monitoring cavity, and the multi-band light source and the multi-band optical detection unit are connected to the optical transmission channel.

[0008] Preferably, the bioresponsive sealant comprises a hydrogel matrix and environmentally responsive microcapsules dispersed in the hydrogel matrix, wherein the hydrogel matrix is ​​a crosslinking system formed by four-arm polyethylene glycol-dopamine and sodium periodate; the four-arm polyethylene glycol-dopamine has a molecular weight of 10 kDa and a grafting rate of 85% to 95%; the shear bond strength of the bioresponsive sealant is not less than 30 kPa; and the gelation time is 20 to 40 seconds.

[0009] The above technical solution enables stable sealing and rapid in-situ gelation of the gastrointestinal anastomosis area. The cross-linking system formed by four-arm polyethylene glycol-dopamine and sodium periodate ensures the adhesion of the sealing gel to moist tissue surfaces and provides a uniform and stable dispersion carrier for environmentally responsive microcapsules, thereby improving the sealing effect and the reliability of the monitoring basis.

[0010] Specifically, the dopamine groups in the four-arm polyethylene glycol-dopamine can form a strong interfacial interaction with the surface of moist tissue, ensuring good adhesion of the sealing adhesive at the gastrointestinal anastomosis. Simultaneously, sodium periodate promotes rapid cross-linking of the system, enabling the sealing adhesive to gel within 20 to 40 seconds, thus meeting the requirements of intraoperative procedures. The four-arm polyethylene glycol-dopamine has a molecular weight of 10 kDa and a grafting rate of 85% to 95%, which ensures a fast gelation rate while improving the integrity and flexibility of the colloidal network. A shear bond strength of not less than 30 kPa ensures that the sealing adhesive maintains stable adhesion even under conditions of gastrointestinal peristalsis and exudate flushing.

[0011] In practical applications, this sealing gel matrix design is better suited to the complex local environment after gastrointestinal anastomosis, especially in scenarios with moist surgical areas, irregular tissue surfaces, and the need for rapid local closure. By constructing a hydrogel matrix with high adhesion and suitable gelation time, not only can the convenience of intraoperative manipulation be improved, but a stable foundation can also be provided for the subsequent triggering and release of environmentally responsive microcapsules and local signal acquisition. Therefore, it is of great significance for improving the overall monitoring effect and structural stability of the system.

[0012] Preferably, the environmentally responsive microcapsules include acid-sensitive microcapsules, wherein the shell material of the acid-sensitive microcapsules is polyβ-amino ester or acrylic resin, the particle size of the acid-sensitive microcapsules is 20 to 50 μm, and the acid-sensitive microcapsules are encapsulated with a red colorimetric agent and an indocyanine green fluorescent tracer.

[0013] The above technical solution enables targeted identification of abnormal signals related to gastric juice. By setting acid-sensitive microcapsules and encapsulating them with a red chromogenic agent and an indocyanine green fluorescent tracer, visual and optical signals can be rapidly generated when gastric juice leaks into the area around the anastomosis, thereby improving the sensitivity and differentiation ability of identifying gastric juice-related leaks.

[0014] Specifically, the shell material of the acid-sensitive microcapsules is poly-β-amino ester or acrylic resin. These materials are prone to structural changes in acidic environments, causing the microcapsule shell to rupture or disintegrate, releasing the encapsulated chromogenic and fluorescent tracers. The microcapsule particle size is controlled within the range of 20 to 50 μm, which balances dispersion uniformity, local response speed, and release stability. The red chromogenic agent can directly reflect the local gastric juice action area, facilitating visual observation; while indocyanine green can generate a corresponding fluorescent signal under excitation of the first wavelength channel, facilitating quantitative or semi-quantitative identification by in vitro intelligent terminals.

[0015] In practical applications, this acid-sensitive microcapsule design is more suitable for monitoring scenarios with high risk of contact with gastric fluid, such as the gastrointestinal anastomosis site after gastrectomy. By simultaneously introducing both visual colorimetric and optical tracer signals, it not only enhances the ability to identify local abnormalities but also improves the system's anti-interference ability in complex postoperative environments, thus playing a significant role in the early detection of gastric fluid-related leakage.

[0016] Preferably, the environmentally responsive microcapsules include enzyme-sensitive microcapsules, wherein the shell of the enzyme-sensitive microcapsules is a polypeptide cross-linked hydrogel, and the cross-linking agent of the polypeptide cross-linked hydrogel includes a Gly-Arg-Gly-Asp-Ser sequence or an Arg-Lys sequence, and the enzyme-sensitive microcapsules are encapsulated with a blue or green chromogenic agent and a sodium fluorescein fluorescent tracer.

[0017] The above technical solution enables targeted identification of abnormal signals related to trypsin-rich fluids. By setting enzyme-sensitive microcapsules and encapsulating them with blue or green chromogenic agents and sodium fluorescein fluorescent tracers, corresponding signals can be rapidly generated when intestinal or pancreatic fluid acts on the area around the anastomosis, thereby achieving the differentiation and identification of different types of leakage.

[0018] Specifically, the shell of the enzyme-sensitive microcapsule is a polypeptide cross-linked hydrogel. The cross-linking agent includes a Gly-Arg-Gly-Asp-Ser sequence or an Arg-Lys sequence. These polypeptide structures can be cleaved in an environment rich in proteolytic enzymes, causing the microcapsule shell network to disintegrate and release its internal substances. A blue or green chromogenic agent can create a visually obvious color change locally, facilitating the observation of the leakage area; sodium fluorescein can generate a stable fluorescence signal under excitation in a second wavelength channel, facilitating signal acquisition and identification by an in vitro terminal. Thus, trypsin-rich fluid-related leakage can be distinguished from gastric juice-related leakage.

[0019] In practical applications, this enzyme-sensitive microcapsule design is particularly suitable for high-risk scenarios such as post-intestinal anastomosis and post-pancreaticoduodenectomy. Because the abnormal fluid composition in these scenarios differs significantly from gastric juice, setting up a dedicated enzyme-sensitive response pathway can improve the system's accuracy and specificity in identifying different leakage types, which is of great value for improving the monitoring of multiple types of abnormal conditions postoperatively.

[0020] Preferably, the intelligent drainage catheter is a medical-grade silicone rubber multi-lumen catheter with a Shore hardness of A50 to A60 and an outer diameter of 18Fr; The main drainage cavity is located in the center of the catheter and has a kidney-shaped or crescent-shaped cross-section with an effective cross-sectional area of ​​not less than 15 mm². The pneumatic monitoring cavity is a circular cross-section cavity with a diameter of 0.8 mm; The optical transmission channel has a diameter of 1.0 mm and is embedded with a polymethyl methacrylate plastic optical fiber. The perfusion cavity has a diameter of 1.0 mm and is equipped with a one-way valve.

[0021] The above technical solution enables integrated arrangement of drainage, pressure monitoring, optical signal transmission, and local fluid perfusion in the gastrointestinal anastomosis area. By employing a medical-grade silicone rubber multi-lumen catheter structure and independently setting up the main drainage cavity, pneumatic monitoring cavity, optical conduction channel, and perfusion cavity, multiple functions can be coordinated within the same catheter body, thereby improving the system's integration level and local arrangement efficiency.

[0022] Specifically, the 18Fr multi-lumen catheter provides sufficient cross-sectional space for multi-channel setup while meeting clinical placement requirements. The main drainage lumen in the center of the catheter adopts a kidney-shaped or crescent-shaped cross-section, ensuring an effective cross-sectional area of ​​not less than 15mm², which helps maintain good drainage capacity. The 0.8mm diameter pneumatic monitoring lumen facilitates communication with the negative pressure generating unit and pressure sensing unit, thereby obtaining the pressure change information required for vacuum attenuation. The 1.0mm diameter optical conduction channel embeds polymethyl methacrylate plastic optical fiber, which can ensure stable transmission of excitation and return light. The 1.0mm diameter perfusion lumen and its internal unidirectional valve can maintain a single perfusion direction and reduce backflow interference.

[0023] In practical applications, this multi-lumen integrated catheter design better meets the needs of patients with limited local placement space and diverse functional requirements after gastrointestinal anastomosis. By concentrating drainage, pressure acquisition, optical detection, and fluid infusion functions into a single catheter, it not only reduces the number of local devices but also helps to reduce the complexity of system layout. Therefore, it is of great significance for improving postoperative monitoring efficiency and overall system synergy.

[0024] Preferably, the anti-adhesion cage is disposed within 30mm of the tip of the intelligent drainage catheter and is composed of 4 to 6 longitudinal ribs extending along the axial direction of the catheter, wherein the height of the longitudinal ribs is 2.0mm to 2.5mm. A side hole communicating with the main drainage cavity is provided between adjacent longitudinal ribs; The surface of the anti-adhesion cage is coated with a polytetrafluoroethylene coating or a hydrophilic hydrogel coating.

[0025] The above technical solution effectively prevents the sealant from being directly sucked into the catheter under negative pressure drainage conditions and maintains a local sampling space around the catheter side holes. By setting an anti-adhesion cage composed of 4 to 6 longitudinal ribs within 30mm of the catheter tip, a stable distance can be maintained between the catheter and the sealant-covered area, thereby improving the system's operational stability under conditions where sealing and drainage coexist.

[0026] Specifically, the anti-adhesion cage is positioned within 30mm of the catheter tip, covering the local area closest to the anastomosis. Four to six longitudinal ribs extending along the catheter axis form a stable support structure, and the rib height of 2.0mm to 2.5mm elevates the catheter side holes from the tissue surface, thereby reducing the risk of the sealing adhesive being directly aspirated into the catheter under negative pressure. Side holes communicating with the main drainage cavity are provided between adjacent longitudinal ribs, facilitating the collection of local exudate into the main drainage cavity. The polytetrafluoroethylene coating or hydrophilic hydrogel coating helps reduce the adhesion tendency between the catheter tip and surrounding tissues or adhesives.

[0027] In practical applications, this anti-adhesion cage structure better meets the needs of postoperative gastrointestinal anastomosis procedures that require both local closure and continuous drainage. Especially when the area covered by the sealing adhesive is close to the area where the catheter is placed, this structure significantly improves catheter patency and system stability, thus playing a crucial role in ensuring accurate local signal acquisition and continuous long-term monitoring.

[0028] Preferably, the negative pressure step output by the negative pressure generating unit is from -10 mmHg to -20 mmHg; The multi-band light source includes a first light source with an excitation wavelength of 780 nm and a second light source with an excitation wavelength of 490 nm; A lock-in amplifier circuit is provided between the multi-band optical detection unit and the central processing unit; The external intelligent terminal is connected to the external end of the intelligent drainage catheter via a magnetic interface.

[0029] The above technical solution enables channel-specific detection of different local abnormal signals and physical monitoring of the catheter status. By setting specific negative pressure step ranges, dual-wavelength light sources, and lock-in amplifier circuits, the stability of vacuum attenuation detection and the accuracy of fluorescence signal recognition can be improved simultaneously, thereby enhancing the system's comprehensive monitoring capabilities.

[0030] Specifically, the negative pressure generation unit outputs a negative pressure step of -10 mmHg to -20 mmHg. This range provides sufficient pressure disturbance to obtain catheter status information while avoiding unnecessary interference to the local environment caused by excessively high negative pressure. A first light source with an excitation wavelength of 780 nm is suitable for exciting indocyanine green-related signals, while a second light source with an excitation wavelength of 490 nm is suitable for exciting sodium fluorescein-related signals. This enables channel-specific identification of abnormal liquid signals from different sources. A lock-in amplifier circuit between the multi-band optical detection unit and the central processing unit extracts target signals consistent with the corresponding excitation frequency, thereby reducing background noise and ambient light interference. The external intelligent terminal connects to the external end of the intelligent drainage catheter via a magnetic interface, facilitating rapid docking and disassembly.

[0031] In practical applications, this terminal configuration better meets the requirements of postoperative continuous monitoring for stability, discriminative power, and portability. Especially when it is necessary to simultaneously determine the properties of local fluid and the status of the catheter, this design can accommodate both optical and pressure detection functions, thus significantly improving the system's monitoring accuracy, ease of operation, and clinical adaptability.

[0032] Preferably, the infusion chamber is a microfluidic channel independent of the main drainage chamber, and its outlet is located within the enclosure of the anti-adhesion cage.

[0033] The above technical solution ensures that the perfusion chamber is structurally independent of the main drainage chamber, and that its output position matches the anti-adhesion cage area at the catheter tip. By placing the outlet of the perfusion chamber within the anti-adhesion cage enclosure, the output medium can be closer to the local monitoring area of ​​the anastomosis, thereby improving the synergistic effect of local fluid perfusion and structure.

[0034] Specifically, the perfusion chamber is a microfluidic channel independent of the main drainage chamber, meaning that the perfusion pathway and drainage pathway are separated, avoiding direct interference between them inside the catheter. The outlet of the perfusion chamber is located within the enclosure of the anti-adhesion cage, allowing the output medium to enter the local space defined by the cage, the catheter tip, and the tissue surface. This is beneficial for verifying the continuity of the perfusion pathway and for ensuring the accessibility and local retention of the output medium within the target area.

[0035] In practical applications, this design of the perfusion cavity outlet position better adapts to the limited local space and complex structural relationships after gastrointestinal anastomosis surgery. By maintaining spatial consistency between the perfusion outlet and the monitoring area at the catheter tip, the synergy between different functional channels of the catheter can be improved, which is of great significance for enhancing the integrated layout and local stability of the system.

[0036] Compared with the prior art, the present invention has the following advantages: 1. This invention integrates a bioresponsive sealing adhesive, a smart drainage catheter, and an external smart terminal into a single unit, forming a continuous working relationship of sealing, data collection, identification, and pathway linkage at the anastomosis site. Compared to solutions with only a single drainage or detection function, this invention is more conducive to maintaining structural synergy during continuous postoperative monitoring, reducing the inconvenience of layout and information fragmentation caused by the dispersion of functional units.

[0037] 2. This invention utilizes two types of environmentally responsive microcapsules—acid-sensitive and enzyme-sensitive—along with optical conduction channels and vacuum attenuation detection structures, enabling the system to not only reflect local abnormal signal changes but also to make a comprehensive judgment based on catheter patency and tissue encapsulation status. This approach helps improve the detail of identifying the local condition around the anastomosis, facilitating postoperative observation and subsequent treatment planning. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the overall structure of the system of the present invention; Figure 2 This is a schematic diagram of the triggering and signal output of the two types of microcapsules of the present invention; Figure 3 This is a schematic diagram of the vacuum attenuation determination process of the present invention; Figure 4 This is a schematic diagram of the vacuum attenuation calibration curve of the present invention; Figure 5 This is a schematic diagram of the fluorescence response calibration curve of the present invention. Detailed Implementation

[0039] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be understood that the following embodiments are for illustrative purposes only and are not intended to limit the scope of protection of the present invention. All equivalent substitutions, improvements, and variations made within the spirit and principles of the present invention should fall within the scope of protection of the present invention.

[0040] I. Workflow, Operating Principle, and Verification Experiment of the Solution This invention provides an intelligent monitoring and repair system for gastrointestinal anastomoses, comprising a bioresponsive sealant, an intelligent drainage catheter, and an external intelligent terminal connected to the intelligent drainage catheter. During the procedure, the bioresponsive sealant is sprayed onto the anastomosis surface to form a sealing layer. The intelligent drainage catheter is then placed near the anastomosis, with the anti-adhesion cage at the catheter tip facing the anastomosis area. After the external intelligent terminal is connected to the external end of the catheter, background fluorescence scanning and vacuum attenuation baseline testing are performed first, followed by continuous monitoring at a preset cycle.

[0041] The bioresponsive sealing gel comprises a hydrogel matrix and environmentally responsive microspheres dispersed within the hydrogel matrix. The environmentally responsive microspheres include acid-sensitive microspheres and enzyme-sensitive microspheres. The acid-sensitive microspheres disintegrate in a gastric acid environment, releasing indocyanine green and a red chromogenic agent; the enzyme-sensitive microspheres lyse in a trypsin-rich liquid environment, releasing sodium fluorescein and a blue chromogenic agent. An in vitro intelligent terminal uses a first wavelength channel and a second wavelength channel for excitation and extracts the target fluorescence signal through lock-in amplification. The intelligent drainage catheter has a main drainage cavity, a pneumatic monitoring cavity, an optical conduction channel, and a perfusion cavity. An anti-adhesion cage at the catheter tip maintains a non-contact distance between the catheter suction port and the coated tissue, preventing negative pressure from drawing the sealing gel into the catheter.

[0042] To verify the feasibility and key technical effects of the system of the present invention, multiple sets of repeated experiments were conducted on material properties, fluorescence response characteristics, vacuum attenuation judgment boundary, and the effectiveness of the anti-adhesion cage.

[0043] 1. Performance verification test of bioresponsive sealing adhesive material A four-arm polyethylene glycol-dopamine solution was used as component A, and a sodium periodate solution was used as component B. Acid-sensitive microspheres and enzyme-sensitive microsphere suspensions were added to component A. The gelation time was determined using the inverted test tube method, and the shear bond strength of the sealing adhesive was determined using the isolated porcine gastric serosa and isolated porcine intestinal serosa overlap shear method.

[0044] The test data for gastric serosa shear adhesion strength, intestinal serosa shear adhesion strength, and gelation time are shown in Table 1. Table 1

[0045] The above results indicate that the bioresponsive sealing adhesive of the present invention has good adhesion to moist tissue surfaces, and the gelation time is within the range suitable for intraoperative spraying.

[0046] 2. Fluorescence response calibration test A simulated anastomotic leakage model was constructed. A 0.8 mm thick bioresponsive sealant was uniformly sprayed onto the model surface, and a smart drainage catheter tip was placed on the outside of the model. The model consisted of three groups: The first group was the simulated gastric juice group, which was supplemented with simulated gastric juice with a pH of 1.5; The second group was the enzyme solution group, which contained a simulated liquid with a trypsin concentration of 1.0 mg / mL. The third group served as the control group, and neutral phosphate buffer was added.

[0047] 50 μL of liquid was added to each group continuously, and the fluorescence signal was detected every 10 minutes for a total of 60 minutes. Five replicate experiments were performed at each time point, and the mean and standard deviation were calculated.

[0048] The statistical results of repeated experiments for fluorescence response calibration in the simulated gastric fluid group are shown in Table 2: Table 2

[0049] The statistical results of the repeated experiments for fluorescence response calibration in the enzyme solution group are shown in Table 3: Table 3

[0050] In the control group, the fluorescence signals of both channels remained near the background value, and were no higher than 1.10 times the background value at any time point.

[0051] Based on the statistical results of the five repeated experiments, an initial alarm threshold can be set when the fluorescence intensity of any channel reaches three times the background value, and a strong alarm threshold can be set when it reaches five times the background value. A schematic diagram of the experimental results is shown below. Figure 5 As shown in the figure. This result demonstrates that the present invention can distinguish and identify gastric juice-related signals and trypsin-rich fluid-related signals.

[0052] 3. Vacuum attenuation calibration test Establish separate models for catheter patency, catheter occlusion, and tissue encapsulation.

[0053] In the catheter patency model, the catheter tip is placed in the open fluid cavity to ensure that the drainage side hole is unobstructed. In the catheter occlusion model, a blood clot-like material was used to seal the main drainage side hole; In the tissue encapsulation model, elastic gelatin and isolated soft tissue are wrapped around the outside of the cage at the tip of the catheter, allowing it to undergo reversible deformation under negative pressure.

[0054] A negative pressure step of -15 mmHg was applied to all three models, maintained for 1 second, and then the micropump was turned off. The pressure recovery curves within 10 seconds were recorded. Twenty replicate experiments were performed for each of the unobstructed, blocked, and tissue-encapsulated models. The test results are shown in Table 4. Table 4

[0055] Accordingly, "pressure recovery within 10 seconds is less than 10%" can be used as the boundary for judging the blockage state, "time constant τ is less than 0.5 seconds" can be used as the boundary for judging the unobstructed state, and "time constant τ is 2 to 5 seconds and accompanied by fluctuations of 1 mmHg to 2 mmHg" can be used as the boundary for judging the tissue encapsulation state. Figure 4 Representative pressure recovery curves under three conditions are shown.

[0056] 4. Verification test of the effectiveness of anti-adhesion cage Two sets of catheters with identical structures were selected. One set was fitted with an anti-adhesion cage, while the other set had its rib structure removed. Both sets of catheters were placed on the simulated surface of an isolated porcine gastric anastomosis coated with bioresponsive sealant. Aspiration was performed continuously for 30 minutes under a negative pressure of -15 mmHg. The residual mass of the sealant before and after the experiment was measured, and the blockage of the side orifices was observed. The experimental results are shown in Table 5. Table 5

[0057] The group with anti-adhesion cages underwent ten repeated experiments, and no side hole blockage occurred in any of the ten repetitions. The group without anti-adhesion cages underwent ten repeated experiments, and side hole blockage occurred in seven of the ten repetitions, with a blockage rate of 70%.

[0058] The above results demonstrate that the anti-adhesion cage can significantly reduce the degree to which the sealing adhesive is sucked into the conduit under negative pressure conditions and can effectively maintain the patency of the side holes.

[0059] 5. System Operation Mode During postoperative monitoring, the in vitro intelligent terminal performs vacuum attenuation detection and fluorescence scanning at preset intervals. An increase in the returned fluorescence signal corresponding to the first wavelength channel indicates that the system has detected gastric fluid-related signals; an increase in the returned fluorescence signal corresponding to the second wavelength channel indicates that the system has detected intestinal fluid-related signals or pancreatic fluid-related signals. The perfusion chamber, as a microfluidic channel independent of the main drainage chamber, can be used for fluid perfusion verification, output of pre-prepared media, and maintenance of local pathway continuity. The system can also output monitoring results corresponding to catheter blockage, catheter patency, or tissue encapsulation status based on the pressure recovery curve.

[0060] Example 1: System Operation Example in the Scenario of Gastric Fluid-Related Signal Monitoring after Gastrectomy This embodiment uses the gastrointestinal anastomosis after gastrectomy as the application scenario. After the anastomosis is completed during the operation, a bioresponsive sealing adhesive is sprayed onto the surface of the anastomosis, with the spray thickness controlled at 0.8 mm. Then, the intelligent drainage catheter is placed near the anastomosis, with the anti-adhesion cage at the tip of the catheter facing the anastomosis area. The external intelligent terminal is then connected to the external end of the catheter for background fluorescence scanning and vacuum attenuation baseline testing.

[0061] The baseline test results showed that the fluorescence intensity of both the first and second wavelength channels was no more than 1.1 times the background value, and the time constant τ was 0.31 seconds, indicating that the catheter was in a patent state.

[0062] Postoperatively, continuous monitoring began. The external intelligent terminal performed vacuum attenuation detection every 15 minutes and fluorescence scanning every 60 minutes. On the second postoperative day, at the 8th hour, a small amount of gastric fluid seeped from the anastomosis area. The acid-sensitive microspheres disintegrated in the acidic environment, releasing indocyanine green and a red chromogenic agent. The first wavelength channel detected a return fluorescence intensity 5.6 times the background value, while the second wavelength channel showed no significant increase. At this time, the drainage fluid changed color to a light red, and the system output gastric fluid-related signals.

[0063] Subsequently, fluid perfusion verification was performed through the perfusion chamber. No significant increase in fluid perfusion resistance was observed, indicating that the perfusion chamber remained patent. Continued monitoring revealed that at 20 hours post-operation on day 2, the fluorescence signal of the first wavelength channel decreased to 2.1 times the background value. On the morning of day 3 post-operation, the fluorescence signal of the first wavelength channel further decreased to 1.3 times the background value. Vacuum attenuation testing on day 6 post-operation showed a time constant τ of 2.8 seconds, accompanied by rhythmic fluctuations of approximately 1.0 mmHg. On day 7 post-operation, the time constant τ was 3.4 seconds, continuing to exhibit a tissue-encapsulated curve. This embodiment demonstrates that the system of the present invention can achieve early signal identification, channel status verification, and monitoring of the healing stage in gastric fluid-related signal monitoring scenarios.

[0064] Example 2: System Operation Example in the Scenario of Pancreatic Fluid-Related Signal Monitoring and Catheter Status Recognition after Pancreaticoduodenectomy This embodiment uses the digestive tract reconstruction area after pancreaticoduodenectomy as the application scenario. After the target anastomosis is completed during the operation, a bioresponsive sealing adhesive is sprayed onto the surface of the anastomosis area, and a smart drainage catheter is placed nearby, maintaining a non-contact distance of 2.0 mm to 2.5 mm between the catheter tip cage and the anastomosis; then, an external smart terminal is connected, and individualized baseline data is established.

[0065] The benchmark test results are as follows: the fluorescence intensity returned by the second wavelength channel is 1.0 times the background value, the fluorescence intensity returned by the first wavelength channel is 1.1 times the background value, and the time constant τ is 0.27 seconds, indicating that the catheter is in a patent state.

[0066] On the first postoperative day, at 16 hours, a small amount of trypsin-rich exudate appeared near the anastomosis. The enzyme-sensitive microspheres lysed, releasing sodium fluorescein and a blue chromogenic agent. The second wavelength channel increased to 4.8 times the background value within 20 minutes, while the first wavelength channel never exceeded 1.4 times the background value. The system therefore output pancreatic juice-related signals.

[0067] To verify the independent structural characteristics between the perfusion chamber and the main drainage chamber, an equal volume of physiological saline was injected into the perfusion chamber as a channel verification solution. During the injection process, the main drainage chamber maintained continuous drainage, and no backflow was observed between the two chambers, indicating that the perfusion chamber can function as an independent microfluidic channel. During monitoring on the 3rd postoperative day, the system experienced a plateau in the pressure curve, with only 6.2% pressure recovery within 10 seconds. No abnormal increases were observed in either fluorescence channel, indicating that this stage primarily represented a localized catheter blockage. After catheter patency restoration, a retest was performed 30 minutes later, and the time constant τ recovered to 0.42 seconds. On the 7th and 8th postoperative days, the time constant τ was 2.9 seconds and 3.5 seconds, respectively, accompanied by rhythmic fluctuations of approximately 1.2 mmHg, suggesting the formation of tissue encapsulation around the catheter. The system output monitoring results corresponding to the healing stage. This embodiment demonstrates that the system of the present invention can simultaneously complete signal identification, channel independence verification, blockage identification, and healing stage monitoring in pancreatic juice-related signal monitoring scenarios.

[0068] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0069] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0070] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A smart monitoring and repairing system for gastrointestinal anastomotic stoma, characterized in that, It includes a bioresponsive sealing adhesive applied to the surface of the gastrointestinal anastomosis, a smart drainage catheter placed near the gastrointestinal anastomosis, and an external smart terminal connected to the external end of the smart drainage catheter. The intelligent drainage catheter includes a main drainage chamber, a pneumatic monitoring chamber, an optical transmission channel, and an infusion chamber. The head end of the intelligent drainage catheter is provided with an anti-adhesion cage. The aforementioned external intelligent terminal includes a negative pressure generating unit, a pressure sensing unit, a multi-band light source, a multi-band optical detection unit, and a central processing unit; The pressure sensing unit is connected to the pneumatic monitoring cavity, and the multi-band light source and the multi-band optical detection unit are connected to the optical transmission channel.

2. The intelligent monitoring and repairing system for gastrointestinal anastomosis according to claim 1, characterized in that, The bioresponsive sealant comprises a hydrogel matrix and environmentally responsive microcapsules dispersed in the hydrogel matrix. The hydrogel matrix is ​​a crosslinking system formed by four-arm polyethylene glycol-dopamine and sodium periodate. The four-arm polyethylene glycol-dopamine has a molecular weight of 10 kDa and a grafting rate of 85% to 95%. The shear bond strength of the bioresponsive sealant is not less than 30 kPa, and the gelation time is 20 to 40 seconds.

3. The intelligent monitoring and repairing system for gastrointestinal anastomosis according to claim 2, characterized in that, The environmentally responsive microcapsules include acid-sensitive microcapsules, the shell material of which is poly-β-amino ester or acrylic resin, the particle size of which is 20 to 50 μm, and the acid-sensitive microcapsules encapsulate a red colorimetric agent and an indocyanine green fluorescent tracer.

4. The intelligent monitoring and repairing system for gastrointestinal anastomosis according to claim 2, characterized in that, The environmentally responsive microcapsules include enzyme-sensitive microcapsules, the shell of which is a polypeptide cross-linked hydrogel, and the cross-linking agent of which includes a Gly-Arg-Gly-Asp-Ser sequence or an Arg-Lys sequence. The enzyme-sensitive microcapsules are encapsulated with a blue or green chromogenic agent and a sodium fluorescein fluorescent tracer.

5. The intelligent monitoring and repairing system for gastrointestinal anastomosis according to claim 1, wherein, The intelligent drainage catheter is a medical-grade silicone rubber multi-lumen catheter with a Shore hardness of A50 to A60 and an outer diameter of 18Fr. The main drainage cavity is located in the center of the catheter and has a kidney-shaped or crescent-shaped cross-section with an effective cross-sectional area of ​​not less than 15 mm². The pneumatic monitoring cavity is a circular cross-section cavity with a diameter of 0.8 mm; The optical transmission channel has a diameter of 1.0 mm and is embedded with a polymethyl methacrylate plastic optical fiber. The perfusion cavity has a diameter of 1.0 mm and is equipped with a one-way valve.

6. The intelligent monitoring and repair system for gastrointestinal anastomosis according to claim 5, characterized in that, The anti-adhesion cage is located within 30mm of the tip of the intelligent drainage catheter and is composed of 4 to 6 longitudinal ribs extending along the axial direction of the catheter, with the height of the longitudinal ribs being 2.0mm to 2.5mm. A side hole communicating with the main drainage cavity is provided between adjacent longitudinal ribs; The surface of the anti-adhesion cage is coated with a polytetrafluoroethylene coating or a hydrophilic hydrogel coating.

7. The intelligent monitoring and repair system for gastrointestinal anastomosis according to claim 1, characterized in that, The negative pressure step output by the negative pressure generating unit is from -10 mmHg to -20 mmHg; The multi-band light source includes a first light source with an excitation wavelength of 780 nm and a second light source with an excitation wavelength of 490 nm; A lock-in amplifier circuit is provided between the multi-band optical detection unit and the central processing unit; The external intelligent terminal is connected to the external end of the intelligent drainage catheter via a magnetic interface.

8. The intelligent monitoring and repair system for gastrointestinal anastomosis according to claim 5, characterized in that, The infusion chamber is a microfluidic channel independent of the main drainage chamber, and its outlet is located within the enclosure of the anti-adhesion cage.

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