Puncture device and system with hematoma monitoring function

Abstract

The invention discloses a puncture device and system with a hematoma monitoring function, and relates to the technical field of biomedical engineering. The device comprises an epidural puncture needle which comprises a needle body and a needle seat; the epidural catheter is used for entering the epidural space through the epidural puncture needle; the front end of the epidural catheter is an imbedding section, the imbedding section is longitudinally imbedded along the epidural cavity after entering the epidural cavity, and an electrical impedance measuring structure is arranged corresponding to the imbedding section and used for measuring the electrical impedance value of the periphery of the imbedding section and transmitting the electrical impedance value to the electrical impedance analyzer; and the electrical impedance analyzer is used for receiving the electrical impedance value and evaluating whether the epidural space has hematoma or not according to the change information of the electrical impedance. According to the invention, the occurrence and development risk of epidural hematoma can be sensitively, timely and accurately identified, so that the clinical medical safety quality can be improved, and the perioperative prognosis of patients can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of biomedical engineering, and particularly relates to a puncture device and system with a hematoma monitoring function. Background Art

[0002] In clinical surgery, anesthesia is a key means for the success of surgery and alleviating the pain of patients. Among them, epidural anesthesia (fully known as epidural space block anesthesia) is a technique commonly used for spinal analgesia, which can effectively reduce the use of opioid drugs while achieving satisfactory analgesic effects, and is widely used in limb surgeries below the abdomen (such as painless childbirth). The main component used in this anesthesia method is an anesthesia catheter, which needs to be inserted into the narrow epidural space. Since the catheter itself is usually made of high molecular material and is relatively soft and unable to penetrate human tissues, an epidural puncture needle is needed to establish a channel to the epidural space. The operation process is summarized as follows: first, the epidural puncture needle is inserted into the epidural space, then the epidural catheter (i.e., the anesthesia catheter) is inserted into the epidural space through the inner cavity of the puncture needle, and then the puncture needle is withdrawn, leaving the epidural catheter in the epidural space. In order to achieve a better anesthetic effect, after the epidural catheter enters the epidural space, it needs to move forward a certain distance along the longitudinal direction of the epidural space towards the head direction of the human body to achieve a better anesthetic effect, as shown in Figure 1 shown.

[0003] There are also potential hazards in the application of epidural anesthesia. One of the main risks is the occurrence of epidural hematoma (EH). Although this situation is relatively rare (about 6 / 1 million), once it occurs, it may lead to serious consequences: epidural hematoma will compress the spinal cord, resulting in neurological dysfunction, causing loss of movement and sensation, and even potentially leading to permanent paralysis. In addition, the formation of epidural hematoma is usually accompanied by symptoms such as acute pain, weakness in the lower limbs, and difficulty in urination, seriously affecting the quality of life of patients.

[0004] The main causes of epidural hematoma (EH) include puncture injury and abnormal coagulation function of patients. Although medical staff will perform strict aseptic operations and technical specifications during epidural puncture, there is still a risk of hematoma due to improper operation or individual vascular variation of patients, and the risk of hematoma formation around the indwelling epidural catheter is relatively high. At present, the detection of epidural hematoma mainly relies on imaging techniques, including magnetic resonance imaging (MRI), computed tomography (CT), ultrasonic exploration, etc. Among them, MRI technology has high resolution and can clearly show the location and scope of the hematoma, but it has the problems of high cost and long examination time; CT has a fast detection speed and high accuracy, but it has radiation and it is difficult to perform continuous or dynamic detection; ultrasonic exploration has the advantages of non-invasiveness, rapidity and bedside availability, but its detection ability for such deep hematomas is limited. In addition, there are also some detection schemes using neuroelectrophysiological examinations, such as electromyogram (EMG), evoked potential (EP), etc., which mainly judge whether a hematoma has occurred by evaluating the nerve function state, conduction ability, etc. The operation is complex, time-consuming, and it is difficult to achieve early diagnosis and timely treatment. It can be seen that the existing monitoring methods are not sensitive to the early detection of epidural hematoma (EH), especially in the initial stage of symptoms, doctors may not be able to identify it in time.

[0005] On the other hand, with the development of bioimpedance technology, the bioelectrical impedance analysis (BIA) technology has been widely used in basic science and clinical science. For example, the conduction and impedance characteristics of electric current by biological tissues such as skin, muscle, fat, blood, bone, and body cavity can be utilized to clearly evaluate the tissue state. As an example, for instance, Chinese Patent Application CN202411708739.8 provides a puncture surgery tissue recognition system based on bioelectrical impedance, including: a double-electrode impedance needle for real-time acquisition of electrical signal data; a feedback display device integrated with a trained random forest model inside, which is used to process the electrical signal data according to the trained random forest model to obtain a classification result; a multi-frequency bioelectrical impedance analyzer for displaying the real-time acquisition waveform and simultaneously displaying the classification result of the random forest model. Among them, the double-electrode impedance needle includes a needle tube structure and an electrode structure located at the head of the needle tube structure; the needle tube structure includes an outer needle tube, an insulating tube layer, and an inner needle core from the outside to the inside; the electrode structure includes an excitation electrode layer, an insulating layer, and a measurement electrode layer from the inside to the outside. The excitation electrode layer is connected with an excitation electrode external cable, and the measurement electrode layer is connected with a measurement electrode external cable; the outer needle tube is connected to the measurement electrode layer, and the inner needle core is connected to the excitation electrode layer. The above technical solution measures the impedance value of biological tissues in the puncture area by setting electrodes on the needle tube of the puncture needle, and then analyzes the clinical state of the organism according to the measurement result, infers the physiological state of the biological tissue, so as to identify the type of biological tissue during the puncture process. Summary of the Invention

[0006] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a puncture device and system with a hematoma monitoring function. Based on the bioelectrical impedance measurement technology and using the characteristic that the impedance of biological tissues changes when their state changes, after improving the puncture device used in epidural anesthesia surgery, the present invention provides a puncture device that can sensitively, timely, and accurately identify the occurrence and development risks of epidural hematoma, thereby helping to improve the quality of clinical medical safety and the prognosis of patients during the perioperative period.

[0007] To achieve the above objectives, the present invention provides the following technical solutions: A puncture device with a hematoma monitoring function, the device includes: An epidural puncture needle, including a needle body and a needle hub; An epidural catheter for entering the epidural space through the epidural puncture needle; the front end of the epidural catheter is an insertion section, which is longitudinally inserted along the epidural space after entering the epidural space. An impedance measurement structure is provided corresponding to the insertion section to measure the impedance value around the insertion section and transmit it to the impedance analyzer; An impedance analyzer is used to receive the aforementioned impedance value and evaluate whether there is a hematoma in the epidural space based on the change information of the impedance.

[0008] Furthermore, the impedance measurement structure at least includes excitation electrodes, a measurement circuit, and a processor. The excitation electrodes are located at both ends of the insertion section. The excitation electrodes are used to apply a current signal to the periphery of the insertion section. The measurement circuit is used to measure the voltage signal between the two excitation electrodes or the voltage signal between the measurement electrodes located between the two excitation electrodes when the excitation electrodes apply a current signal to the periphery of the insertion section. The processor is used to calculate the corresponding impedance based on the aforementioned current signal and voltage signal as the impedance of the periphery of the insertion section.

[0009] Furthermore, the electrode is in a ring structure and sleeved outside the insertion section catheter. The ring electrode protrudes relative to the outer surface of the insertion section catheter or is flush with the outer surface of the insertion section catheter.

[0010] Furthermore, an inflatable structure is arranged inside the ring electrode to form an inflation ring. When the inflatable structure is in a non-inflated state, the ring electrode is received in the catheter wall and is flush with the outer surface of the catheter. When the inflatable structure is in an inflated state, it drives the ring electrode to protrude outward relative to the catheter, so as to facilitate impedance measurement.

[0011] Furthermore, the inflatable structure includes an inflatable body and an inflation control circuit. A conductive material is arranged on the outer surface of the inflatable body to form an electrode. The inflation control circuit is communicatively connected with the impedance analyzer. The impedance analyzer is configured to: when it is judged that the epidural space is evolving towards a hematoma, send an inflation control instruction to the inflation control circuit. The inflation control circuit is configured to: after receiving the aforementioned inflation control instruction, control the inflatable body to inflate.

[0012] Furthermore, the inflatable body is an airbag with a hollow capsule body. The capsule body is connected to an external inflation structure so that the capsule body can be inflated.

[0013] Furthermore, the insertion section includes an inner tube and an outer tube. The inner tube serves as an anesthesia catheter, and at least a first electrode is arranged on the inner tube. The outer tube is nested outside the inner tube and can move relative to the inner tube. At least a second electrode is arranged on the outer tube. The outer tube is connected to an external traction controller through a traction structure. The traction controller is used to drive the traction structure to act to adjust the relative position between the outer tube and the inner tube, so as to adjust the distance between the two electrodes to adjust the monitoring range.

[0014] Further, the inserted segment includes an inner tube and an outer tube. The inner tube serves as an anesthesia catheter, and the outer tube is nested outside the inner tube and can move relative to the inner tube; The outer tube includes a plurality of tube units, which are connected by a dynamic measurement segment. Electrodes are respectively arranged on the tube units; the dynamic measurement segment is connected to an external adjustment controller, and the length of the dynamic measurement segment in the axial direction of the catheter in the inserted segment is changed through the adjustment controller to adjust the distance between the plurality of tube units, so as to adjust the distance between the electrodes and adjust the monitoring range.

[0015] Further, the dynamic measurement segment adopts a flexible airbag tube. The two ends of the airbag tube are respectively fixedly connected to the tube units on both sides, and the airbag tube is communicated with the adjustment controller through a delivery pipeline. The adjustment controller includes a filling device and a suction device; The adjustment controller is configured to: receive a dynamic measurement adjustment instruction. When the dynamic measurement adjustment instruction is to increase the monitoring range, control the delivery pipeline to be communicated with the filling device to inflate the airbag tube and increase the length of the dynamic measurement segment in the axial direction of the catheter in the inserted segment; when the dynamic measurement adjustment instruction is to decrease the monitoring range, control the delivery pipeline to be communicated with the suction device to deflate the airbag tube and decrease the length of the dynamic measurement segment in the axial direction of the catheter in the inserted segment.

[0016] The present invention also provides a hematoma monitoring and evaluation system, which includes a puncture device and a user terminal. The puncture device is the aforementioned puncture device with a hematoma monitoring function; The user terminal is configured to: receive the analysis result of the impedance analyzer and display and output it; and collect the operation instruction of the user, and control the impedance measurement structure and / or the impedance analyzer to execute the operation according to the operation instruction.

[0017] Due to the adoption of the above technical solutions, compared with the prior art, for example, the present invention has the following advantages and positive effects: Based on the bioelectrical impedance measurement technology, using the characteristic that the bioelectrical impedance of biological tissues will change when their states change, after improving the puncture device used in epidural anesthesia surgery, the present invention provides a puncture device that can sensitively, timely and accurately identify the occurrence and development risks of epidural hematoma, thereby helping to improve the quality of clinical medical safety and improve the prognosis of patients during the perioperative period.

[0018] Further, the electrode structure of the impedance measurement structure is improved to provide electrodes that can adjust the measurement state and monitoring range, so as to better measure the state of the epidural cavity near the inserted segment and evaluate the occurrence and development information of the epidural hematoma. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the indwelling of an epidural catheter in the epidural cavity.

[0020] Figure 2 It is a schematic diagram of a spinal section.

[0021] Figure 3 It is a schematic structural diagram of a puncture device with a hematoma monitoring function provided by an embodiment of the present invention.

[0022] Figure 4 It is a schematic diagram of an epidural puncture needle provided by an embodiment of the present invention.

[0023] Figure 5 It is a schematic diagram of an epidural catheter with an insertion section provided by an embodiment of the present invention.

[0024] Figure 6 It is a schematic diagram of the state after the catheter insertion section is left in place provided by an embodiment of the present invention.

[0025] Figure 7 It is a schematic structural diagram of an electrode before inflation provided by an embodiment of the present invention.

[0026] Figure 8 It is a schematic structural diagram of an electrode after inflation provided by an embodiment of the present invention.

[0027] Figure 9 It is a schematic structural diagram of an electrode using an airbag inflation ring provided by an embodiment of the present invention.

[0028] Figure 10 It is a schematic structural diagram of an insertion section including an inner tube and an outer tube provided by an embodiment of the present invention.

[0029] Figure 11 It is a schematic structural diagram of an insertion section with a dynamic measurement section provided by an embodiment of the present invention.

[0030] Explanation of reference numerals: Puncture device 10; Epidural puncture needle 100, needle body 110, needle tip 111, needle hub 120; Epidural catheter 200, catheter placement accessory 201, insertion section 210, inner tube 2101, outer tube 2102, tube unit 21, dynamic measurement section 22, catheter head section 211, electrode 212, conductive layer 2121, airbag cavity 2122, opening 2123, delivery pipeline 2124, wire 213; Electrical impedance analyzer 300; Anesthetic syringe 400. Detailed implementation manners

[0031] The following further elaborates on the puncture device and system with a hematoma monitoring function disclosed in the present invention in conjunction with the accompanying drawings and specific embodiments. It should be noted that the technical features or combinations of technical features described in the following embodiments should not be considered in isolation, and they can be combined with each other to achieve better technical effects. In the accompanying drawings of the following embodiments, the same reference numerals appearing in each drawing represent the same features or components, which can be applied to different embodiments. Therefore, once a certain item is defined in one drawing, it does not need to be further discussed in the subsequent drawings.

[0032] It should be noted that the structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those skilled in this technology to understand and read, and are not used to limit the limiting conditions under which the invention can be implemented. Any modification of the structure, change in the proportional relationship, or adjustment of the size, without affecting the efficacy that the invention can produce and the purpose that can be achieved, should fall within the scope covered by the technical content disclosed in the invention. The scope of the preferred implementation manner of the present invention includes additional implementations, in which the functions can be executed in a substantially simultaneous manner or in the reverse order according to the functions involved, rather than in the order described or discussed. This should be understood by those skilled in the technical field to which the embodiments of the present invention belong.

[0033] For technologies, methods, and devices known to those of ordinary skill in the relevant field, they may not be discussed in detail, but in appropriate cases, the said technologies, methods, and devices should be regarded as a part of the authorized specification. In all the examples shown and discussed here, any specific value should be interpreted as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values.

[0034] In the description of the embodiments of the present application, " / " means "or", and "and / or" is used to describe the association relationship of associated objects, indicating that three relationships can exist. For example, "A and / or B" means: A exists alone, B exists alone, and both A and B exist simultaneously. In the description of the embodiments of the present application, "a plurality of" means two or more. Embodiment

[0035] Impedance is a resistance that interferes with the flow of current and depends on the vector sum of resistance and reactance. In the human body, the difference between the values of impedance and resistance is small, and the two can be used interchangeably. As a basic physical parameter of biological tissues, impedance has long received extensive attention from biophysicists and physiologists.

[0036] Bioelectrical impedance measurement is a detection technique that utilizes the electrical properties of biological tissues and organs and their variation laws to extract biomedical information related to the physiological and pathological conditions of the human body. It usually sends a tiny alternating current or voltage to the detection object through an electrode system placed on the body surface, detects the corresponding impedance and its variation, and then obtains relevant physiological and pathological information according to different application purposes. Currently, in the measurement of biological tissue impedance, the commonly used methods are the two-electrode method and the four-electrode method. Among them, the two-electrode measurement technique introduces the current signal into the biological tissue to be measured through a pair of electrodes, and then detects the voltage at both ends through the same pair of electrodes; the measurement electrodes of the four-electrode method generally consist of four metal electrodes, and the four metal electrodes are arranged in a row. The outer pair of metal electrodes serve as excitation electrodes, and the inner pair of metal electrodes serve as measurement electrodes. During measurement, the metal electrodes can be inserted into the tissue to be measured or attached to the surface of the tissue to be measured.

[0037] The epidural space, also known as the epidural cavity, is the space between the dura mater spinalis and the periosteum on the inner surface of the vertebral canal, containing the internal vertebral venous plexus, loose connective tissue and fat, and the spinal nerves pass through it. Since the epidural space does not communicate with the intracranial cavity, this space is slightly negative in pressure. See Figure 2 As shown, the epidural space is a discontinuous space, roughly divided into 4 spaces in the front, back and both sides by the nerve roots on both sides. Among them, the posterior epidural space is located between the posterior side of the posterior root epidural and the periosteum of the vertebral arch and the ligamentum flavum. The posterior space in the entire cervical segment is very narrow, about 1.5 mm, and the upper cervical segment may be closed; from the thoracic segment downwards, the posterior space gradually widens. The middle thoracic segment is about 2 - 4 mm wide, and the segment of L2 - 3 can reach 6 mm. There is a relatively developed internal vertebral venous plexus in the posterior space, but it is less near the posterior midline. It is the site for indwelling the epidural catheter (the catheter is usually indwelled 2 - 5 cm in the epidural cavity and can be appropriately adjusted according to factors such as the patient's age and weight). When performing epidural catheterization, the catheter has to squeeze through and penetrate some connective tissue and fat in the epidural space during its advancement, and there is a relatively high risk of damaging blood vessels and forming a hematoma around the indwelling catheter during this process.

[0038] Based on the bioelectrical impedance measurement technology, the present invention utilizes the characteristic that the impedance of biological tissues changes when their state changes, and evaluates the existence and characteristics of the hematoma by detecting the impedance change of the epidural space - because the hematoma will cause changes in tissue impedance.

[0039] Specifically, the present invention provides a puncture device with a hematoma monitoring function. After the epidural catheter is inserted, a weak current is applied to the epidural tissue through the indwelling catheter and the voltage is measured, the impedance is calculated according to the measured value, and the occurrence information of the hematoma in the epidural space is evaluated according to the change of the impedance.

[0040] See Figure 3As shown, the typical structure of the puncture device with hematoma monitoring function provided by the present invention is exemplified. The puncture device 10 includes an epidural puncture needle 100 and an epidural catheter 200. An impedance measurement structure is provided corresponding to the epidural catheter 200 for measuring the impedance value around the inserted segment of the catheter and transmitting it to the impedance analyzer 300. An anesthetic syringe 400 is also connected corresponding to the epidural catheter.

[0041] See Figure 4 As shown, the epidural puncture needle 100 includes a needle body 110 and a needle hub 120.

[0042] The needle body 110 may include a needle tube, and the material of the needle tube is medical stainless steel. One end of the needle tube is a needle tip 111, and the other end is fixed with a needle hub 120 that communicates with the needle tube. The front end of the needle tip 111 is a needle opening, and the needle opening is an oval shape close to a circle. An operation handle and a catheter insertion joint may be provided on the needle hub 120, and a flap-type seal valve is hermetically provided at the rear end of the catheter insertion joint.

[0043] The rear end of the catheter insertion joint of the needle hub 120 is used for detachable connection with the catheter insertion accessory 201 of the epidural catheter 200. When catheter insertion is required, after inserting the catheter insertion accessory 201 into the rear end interface of the catheter insertion joint, the epidural catheter 200 is inserted through the inner cavity of the needle hub and the inner cavity of the needle tube, so that the epidural catheter 200 enters the epidural space through the epidural puncture needle 100.

[0044] During use, insert the needle tube of the epidural puncture needle into the human tissue at the current position. When the puncture needle passes through the ligamentum flavum and reaches the epidural space between the ligamentum flavum and the dura mater (there is an obvious sense of falling through), at this time, after judging that the needle tip 111 of the needle tube reaches the epidural space, insert the epidural catheter 200 into the needle tube. After the head end of the epidural catheter 200 enters the epidural space through the inner cavity of the puncture needle, it bends towards the patient's head direction through the needle opening under the guidance of the needle tip 111 and advances longitudinally in the epidural space. After the catheter insertion is completed, withdraw the puncture needle, leave the catheter in the epidural space, fix the catheter, and give local anesthetic drugs through the catheter. The epidural catheter 200 is a flexible tube and can adopt a reinforced epidural catheter (provided with a reinforcing liner). A spring is arranged inside the catheter wall of the reinforced epidural catheter to resist bending, is not easy to kink and break, and reduces the risks of blockage and catheter breakage.

[0045] See Figure 5 As shown, the front end of the epidural catheter 200 is an inserted segment 210, which is longitudinally inserted along the epidural space after entering the epidural space and is basically parallel to the longitudinal direction of the epidural space. See Figure 6 As shown.

[0046] The front end of the inserted segment 210 is the catheter tip segment 211, and openings are provided on the catheter tip segment 211 for liquid passage (such as administration of anesthetic drugs). The openings can be provided at the tip and / or the side wall of the catheter tip segment 211, and multiple rows can be provided, such as 4 rows, and one or more openings can be provided in each row.

[0047] An impedance measurement structure is provided corresponding to the inserted segment 210 for measuring the impedance value around the inserted segment and transmitting it to the impedance analyzer 300. The impedance analyzer 300 is used to receive the aforementioned impedance value and evaluate whether there is a hematoma in the epidural cavity based on the change information of the impedance.

[0048] When specifically arranged, the impedance measurement structure at least includes excitation electrodes, a measurement circuit, and a processor.

[0049] The excitation electrodes are a pair and can be respectively located at both ends of the catheter inserted segment 210. See Figure 5 and Figure 6 As shown, a pair of metal electrodes 212 are respectively arranged at both ends of the inserted segment 210 as excitation electrodes. Among them, the first electrode is close to the catheter tip segment 211 and is located at the distal end of the inserted segment 210, and the second electrode is far from the catheter tip segment 211 (close to the dural puncture needle) and is located at the proximal end of the inserted segment 210.

[0050] The excitation electrodes are used to apply a current signal to the periphery of the inserted segment. The applied current signal can be a constant current or an alternating current with a constant amplitude.

[0051] The measurement circuit is used to measure the voltage signal between the two excitation electrodes at both ends when the aforementioned excitation electrodes apply a current signal to the periphery of the inserted segment (corresponding to the two-electrode method, the excitation electrodes are also measurement electrodes). At this time, the measurement circuit directly measures the voltage between the two excitation electrodes, and only two electrodes need to be set at this time.

[0052] Alternatively, the measurement circuit is used to measure the voltage signal between the measurement electrodes located between the excitation electrodes at both ends when the excitation electrodes apply a current signal to the periphery of the inserted segment. At this time, a section is selected between the two excitation electrodes to measure the corresponding voltage of this section. At this time, at least two measurement electrodes also need to be provided on the inserted segment, and the tissue length between the two measurement electrodes is the measurement section. Taking the four-electrode setting as an example, the four metal electrodes can be arranged in a row. The pair of outer metal electrodes are used as excitation electrodes for injecting and measuring current, and the pair of inner metal electrodes are used as measurement electrodes for measuring the voltage drop (corresponding to the four-electrode method, separating current injection and voltage measurement). See Figure 7 as shown.

[0053] The processor is configured to calculate the corresponding impedance based on the aforementioned current signal and the real-time voltage signal, and use it as the impedance value of the periphery of the implanted segment at the current time. Specifically, the processor is configured to perform the following calculations: obtain the measured voltage drop V and the injected current I, calculate the resistance R = V / I according to Ohm's law, and use this calculated value as the impedance value of the periphery of the implanted segment; and, feedback the calculation result to the impedance analyzer in real time, and the feedback data includes the impedance value and the current time information.

[0054] In this embodiment, the electrodes of the impedance measurement structure are arranged on the implanted segment 210 (located in the epidural space). The measurement circuit may specifically include an external cable and a voltage measurement component. The voltage measurement component may be arranged at the tail end of the epidural catheter 200. The external cable is routed inside the catheter wall of the epidural catheter 200 to connect the in-vivo electrode and the external voltage measurement component; the processor is located outside the body and may be integrally arranged with the voltage measurement component, and is arranged at the tail end of the epidural catheter 200. The processor is communicatively connected to the impedance analyzer 300 for information interaction.

[0055] In this embodiment, the impedance analyzer 300 can receive the impedance data sent by the aforementioned processor in real time and continuously, and then evaluate whether there is a hematoma in the epidural space according to the change information of the impedance.

[0056] Specifically, a hematoma risk analysis module may be provided in the impedance analyzer 300. The hematoma risk analysis module is configured to: according to the received data, calculate the change amount Ri of the impedance value within each time interval period Ti according to a preset time interval period T, where i represents the number of periods, which is an integer greater than or equal to 1, i = 1, 2, 3,..., Ti represents the i-th time interval period, and Ri represents the change value of the impedance value within the i-th time interval period, with the unit of Ω; compare the change amount Ri with a preset change amplitude threshold Rk. When the change amount Ri is greater than or equal to the change amplitude threshold Rk, it is determined that there is a risk of the epidural space evolving towards a hematoma, that is, there is a hematoma risk, and a hematoma risk warning can be issued and a prompt for hematoma depth detection can be given. When the change amount Ri is less than the change amplitude threshold Rk, it can be determined that there is no hematoma risk at present. At this time, the monitoring can continue in the existing manner.

[0057] The change amplitude threshold Rk is mainly related to factors such as the type of biological tissue, the magnitude of the injected current during measurement, and the alternating current amplitude (if alternating current testing is used). In this embodiment, it can be set by the system default or can be personalized by the user according to needs.

[0058] Preferably, in the impedance analyzer, corresponding reference resistance values Rb and amplitude threshold reference ratios λ are configured for different types of biological tissues in combination with several common current injection situations. The reference resistance value Rb represents the reference resistance value of this type of biological tissue under normal conditions (without hematoma). The amplitude threshold reference ratio λ is used to calculate the aforementioned change amplitude threshold Rk. As an example, for a certain type of biological tissue, the corresponding current injection situations are divided into two types (one is a preset constant current injection, and the other is a preset amplitude alternating current injection), and corresponding reference resistance values Rb and amplitude threshold reference ratios λ are configured for these two situations respectively.

[0059] At this time, the impedance analyzer may include a user interface and an initialization module.

[0060] The user interface is used to collect information on the type of biological tissue and the type of current injection input by the user in the information collection column. Alternatively, the user interface is used to collect information on the target biological tissue type and the type of current injection selected by the user. At this time, an option list is provided for the user to select, and the user can select the specific types of biological tissue types and current injection types displayed in the option list.

[0061] The initialization module is configured to: obtain the target biological tissue type and the type of current injection input or selected by the user, obtain the corresponding reference resistance value Rb and amplitude threshold reference ratio λ from the aforementioned configuration information, and determine the corresponding change amplitude threshold Rk according to the reference resistance value Rb and the amplitude threshold reference ratio λ. The change amplitude threshold Rk is the product of the aforementioned reference resistance value Rb and the amplitude threshold reference ratio λ.

[0062] As an example but not a limitation, for example, the biological tissue type selected by the user is the epidural space tissue, and the current injection type is to inject a constant current I 0 , and the obtained corresponding amplitude threshold reference ratio λ is 10%, then the change amplitude threshold Rk is the aforementioned reference resistance value Rb multiplied by 10%.

[0063] Furthermore, considering that hematoma is a gradually forming process, and during this process, the impedance change of the epidural space tissue shows a certain regularity. Therefore, a corresponding hematoma-impedance change law model is configured for each type of biological tissue in the impedance analyzer. The hematoma-impedance change law model records the impedance change law of this biological tissue from no hematoma to gradually developing into a hematoma of a preset size (which can be obtained based on a bioelectrical impedance measurement experiment on this biological tissue).

[0064] At this time, the hematoma risk analysis module is further configured to: obtain the target biological tissue type input or selected by the user, and obtain the hematoma-impedance change rule model corresponding to the target biological tissue type; sort the impedance values and the corresponding current time information obtained from the impedance measurement structure in chronological order to form the real-time change rule of the impedance value over time, and compare the real-time change rule with the impedance change rule recorded in the aforementioned hematoma-impedance change rule model. When the matching degree between the real-time change rule and the impedance change rule is greater than or equal to a preset threshold (such as 70%), it is determined that there is a risk of hematoma development, a hematoma development warning is issued and it is prompted to perform hematoma depth detection; when the matching degree between the real-time change rule and the impedance change rule is less than the preset threshold, it can be determined that there is no risk of hematoma development at present. At this time, the monitoring can continue in the existing manner.

[0065] Preferably, the hematoma development warning information may further include hematoma development stage information. As an example, for instance, the hematoma development stage may include five stages: the micro-miniature hematoma stage, the small hematoma stage, the medium hematoma stage, the medium-large hematoma stage, and the large hematoma stage. In the hematoma-impedance change rule model, the impedance reference ranges for the above-mentioned hematoma development stages are configured. After it is determined that there is a risk of hematoma development, the hematoma risk analysis module may further be configured to: obtain the impedance value data at the latest N moments, determine which stage's impedance reference range the impedance value data at the aforementioned N moments is located in, and take the corresponding stage as the current hematoma development stage. The N is an integer greater than or equal to 2.

[0066] Furthermore, when N = 2 and the two impedance value data are respectively located in two hematoma development stages, the more severe stage can be selected as the current hematoma development stage; when N is greater than or equal to 3 and the N impedance value data are located in different hematoma development stages, the stage in which the most data fall can be selected as the current hematoma development stage.

[0067] In this way, the impedance analyzer can receive the impedance data sent by the aforementioned processor in real time and continuously, and then evaluate whether there is a hematoma in the epidural cavity and the hematoma development information according to the change information of the impedance.

[0068] In a preferred embodiment, the electrode is in a ring structure and sleeved outside the catheter of the insertion section 210. The ring electrode can protrude relative to the outer surface of the insertion section catheter or be flush with the outer surface of the insertion section catheter. See Figure 7 As shown, at this time, that is, the outer surface diameter of the ring electrode is equal to the outer surface diameter of the catheter. The inner side of the ring electrode can be embedded in the catheter wall of the insertion section 210 but the outer surface is exposed in the epidural cavity to be able to apply a current signal to the cavity.

[0069] In one embodiment, an expandable structure may be further disposed inside the annular electrode to form an expansion ring.

[0070] The expandable structure has a non-expanded state and an expanded state. In the non-expanded state, the annular electrode is received in the catheter wall and flush with the outer surface of the catheter; in the expanded state, it can drive the annular electrode to protrude outward relative to the catheter, forming a protruding electrode structure, as shown in Figure 8 shown, so as to facilitate measuring the impedance.

[0071] Specifically, the expandable structure may include an expandable body and an expansion control circuit. The expansion control circuit is communicatively connected to the impedance analyzer and can perform information interaction.

[0072] The impedance analyzer is configured to: when it is determined that the epidural space is evolving towards a hematoma, send an expansion control instruction to the expansion control circuit.

[0073] The expansion control circuit is configured to: after receiving the expansion control instruction sent by the aforementioned impedance analyzer, control the expandable body to expand.

[0074] In a preferred embodiment, the expandable body is an airbag, which has a hollow bladder. The bladder is connected to an external inflation structure so that the bladder can be inflated and expanded, as shown in Figure 9 shown. An opening 2123 is provided on the bladder. The opening 2123 is connected to an external inflation structure (such as an air pump) through a delivery pipeline 2124. A conductive layer 2121 is provided on the outer side of the bladder as an electrode. The conductive layer 2121 is connected to an external voltage measurement component through a wire 213 (and an external cable). At this time, the wire 213 can be led out through the delivery pipeline 2124. The delivery pipeline 2124 can be provided on the catheter wall of the epidural catheter 200. After the bladder is inflated and expanded, an airbag cavity 2122 is formed, driving the annular electrode to expand and protrude outward.

[0075] Preferably, the conductive layer 2121 is a conductive material coated on the surface of the bladder, or a metal ring formed by a metal spiral, which can expand and contract with the bladder. Alternatively, the conductive layer 2121 is a conductive ring assembled by a plurality of arc-shaped metal sheets, and the arc-shaped metal sheets can be connected by a conductive elastic structure (such as a spring) to adapt to the expansion and contraction of the bladder.

[0076] Considering the need for adjusting the monitoring range, the catheter structure of the implanted segment is improved in this embodiment.

[0077] See Figure 10As shown, in one embodiment, the inserted section 210 of the epidural catheter 200 may include an inner tube 2101 and an outer tube 2102 which are nested. The inner tube 2101 serves as an anesthesia catheter, and at least a first electrode is provided on the inner tube 2101. The outer tube 2102 is sleeved outside the inner tube and can move relative to the inner tube 2101, and at least a second electrode is provided on the outer tube 2102.

[0078] A traction structure is provided corresponding to the outer tube 2102. The traction structure is connected to an external traction controller. By driving the traction structure to act through the traction controller, the relative position between the outer tube 2102 and the inner tube 2101 is adjusted, that is, the outer tube 2102 is controlled to move relative to the inner tube 2101, so as to adjust the distance between the electrodes 212, thereby adjusting the monitoring range.

[0079] As an example of a typical method, the traction structure may adopt a traction wire. The traction wire may be one or more. One end of each traction wire is fixedly connected to the outer tube, and the other end is connected to an external traction controller. By driving the traction wire to wind, the outer tube moves relative to the inner tube.

[0080] Continue to refer to Figure 10 As shown, taking the two-electrode method as an example, current is introduced into the biological tissue to be measured through a pair of excitation electrodes 212, and then the voltage at both ends of the pair of excitation electrodes 212 is measured. By adjusting the distance between the two excitation electrodes 212, the monitoring range around the inserted section is adjusted.

[0081] When the four-electrode method is adopted, it further includes a pair of measurement electrodes. In order to adjust the distance between the measurement electrodes to adjust the measurement range, a first excitation electrode and a first measurement electrode may be provided on the inner tube 2101. The first excitation electrode is located outside the first measurement electrode. A second excitation electrode and a second measurement electrode are provided on the outer tube 2102. The second excitation electrode is located outside the second measurement electrode. By controlling the outer tube 2102 to move relative to the inner tube 2101, the distance between the two excitation electrodes 212 changes, and at the same time the distance between the two measurement electrodes also changes, thereby adjusting the measurement range.

[0082] Refer to Figure 11As shown, in another embodiment, the inserted segment 210 of the epidural catheter 200 may include an inner tube 2101 and an outer tube 2102 nested with each other. The inner tube 2101 serves as an anesthesia catheter, and the outer tube 2102 is sleeved outside the inner tube and can move relative to the inner tube 2101. The outer tube 2102 includes a plurality of tube units 21, and adjacent tube units 21 are connected by a dynamic measurement segment 22. Excitation electrodes 212 are respectively arranged on the tube units 21; the dynamic measurement segment 22 is connected to an external adjustment controller, and the length of the dynamic measurement segment 22 in the axial direction of the inserted segment catheter is changed through the adjustment controller to adjust the distance between the plurality of tube units, so as to adjust the distance between the electrodes, thereby adjusting the monitoring range.

[0083] In a preferred embodiment, the dynamic measurement segment 22 adopts a flexible airbag tube. Both ends of the airbag tube are fixedly connected to the two side tube units 22 respectively, and the airbag tube is communicated with the adjustment controller through a delivery pipeline. The adjustment controller includes a filling device and a suction device.

[0084] The adjustment controller is configured to: receive a dynamic measurement adjustment instruction. When the dynamic measurement adjustment instruction is to increase the monitoring range, control the delivery pipeline to be communicated with the filling device to inflate the airbag tube, increasing the length of the dynamic measurement segment in the axial direction of the inserted segment catheter; when the dynamic measurement adjustment instruction is to decrease the monitoring range, control the delivery pipeline to be communicated with the suction device to deflate the airbag tube, decreasing the length of the dynamic measurement segment in the axial direction of the inserted segment catheter.

[0085] It should be noted that Figure 11 taking the two-electrode method as an example to illustrate the adjustment of the distance between two electrodes. When the four-electrode method is adopted, it further includes a pair of measurement electrodes. At this time, preferably, at least 4 tube units 21 can be provided, and adjacent tube units 21 are all connected by a dynamic measurement segment 22, that is, 3 dynamic measurement segments 22 are provided. Electrodes are respectively arranged on each tube unit 21. For example, a first excitation electrode can be arranged on the first tube unit 21, a first measurement electrode can be arranged on the second tube unit 21, a second measurement electrode can be arranged on the third tube unit 21, and a second excitation electrode can be arranged on the fourth tube unit 21. The first excitation electrode is located outside the first measurement electrode, and the second excitation electrode is located outside the second measurement electrode. When the dynamic measurement segment 22 between the tube units 21 is inflated or deflated, the length of the dynamic measurement segment 22 changes, and the distance between the tube units 21 also changes, prompting the distance between the electrodes to change, thereby adjusting the monitoring range.

[0086] Another embodiment of the present invention further provides a hematoma monitoring and evaluation system.

[0087] The system includes a puncture device and a user terminal.

[0088] The puncture device includes an epidural puncture needle and an epidural catheter. An impedance measurement structure is provided corresponding to the epidural catheter for measuring the impedance value around the inserted section of the catheter and transmitting it to an impedance analyzer. An anesthetic syringe is also connected to the epidural catheter.

[0089] The epidural puncture needle includes a needle body and a needle hub.

[0090] The epidural catheter is used to enter the epidural space through the epidural puncture needle; the front end of the epidural catheter is the inserted section, which is longitudinally inserted along the epidural space after entering the epidural space. An impedance measurement structure is provided corresponding to the inserted section for measuring the impedance value around the inserted section and transmitting it to the impedance analyzer.

[0091] The impedance analyzer is used to receive the aforementioned impedance value and evaluate whether there is a hematoma in the epidural space based on the change information of the impedance.

[0092] The user terminal is configured to: receive the analysis result of the impedance analyzer and display and output it; and collect the operation instructions of the user, and control the impedance measurement structure and / or the impedance analyzer to perform corresponding operations according to the operation instructions.

[0093] For other technical features, refer to the description of the previous embodiments and will not be elaborated here.

[0094] In the above description, the disclosure of the present invention is not intended to limit itself to these aspects. Instead, within the scope of the object protection of the present disclosure, each component can be selectively and operably combined in any number. Additionally, terms such as "including", "comprising", and "having" should be construed as inclusive or open by default, rather than exclusive or closed, unless it is explicitly defined to the contrary. All technical, scientific, or other terms conform to the meanings understood by those skilled in the art, unless it is defined to the contrary. Common terms found in the dictionary should not be interpreted too idealistically or too unrealistically in the context of the relevant technical documents, unless the present disclosure explicitly defines it as such. Any changes and modifications made by those of ordinary skill in the art of the present invention based on the above disclosure fall within the protection scope of the claims.

Claims

1. A puncture device with hematoma monitoring function, characterized in that include: An epidural puncture needle, comprising a needle body and a needle seat; An epidural catheter is used to enter the epidural space through the epidural puncture needle; the front end of the epidural catheter is an insertion section, which is inserted longitudinally along the epidural space after entering the epidural space, and the corresponding insertion section is set to measure the electrical impedance value around the insertion section and transmit it to the electrical impedance analyzer; The electrical impedance analyzer is used to receive the aforementioned electrical impedance value and evaluate whether there is a hematoma in the epidural space based on the change information of the electrical impedance.

2. The puncture device according to claim 1, characterized in that: The electrical impedance measurement structure at least includes an excitation electrode, a measurement circuit and a processor, wherein the excitation electrodes are located at both ends of the implantation section; The excitation electrode is used to apply a current signal to the periphery of the implanted segment; The measuring circuit is used to measure the voltage signal between the excitation electrodes at both ends or the voltage signal between the measuring electrodes located between the excitation electrodes at both ends when the excitation electrodes apply a current signal to the periphery of the implanted segment; The processor is used to calculate the corresponding electrical impedance according to the above-mentioned current signal and voltage signal as the electrical impedance around the implanted segment.

3. The puncture device according to claim 2, characterized in that: The electrode is an annular structure and is sleeved outside the insertion section catheter; The annular electrode protrudes relative to the outer surface of the implanted section catheter or is flush with the outer surface of the implanted section catheter.

4. The puncture device according to claim 3, characterized in that: An expandable structure is arranged inside the annular electrode to form an expansion ring. When the expandable structure is in a non-expanded state, the annular electrode is housed in the catheter wall and flush with the outer surface of the catheter; when the expandable structure is in an expanded state, the annular electrode is driven to bulge outward relative to the catheter, thereby facilitating the measurement of electrical impedance.

5. The puncture device according to claim 4, characterized in that: The expandable structure includes an expandable body and an expansion control circuit, a conductive material is arranged on the outer surface of the expandable body to form an electrode, and the expansion control circuit is in communication connection with the electrical impedance analyzer; The electrical impedance analyzer is configured to: when it is determined that the epidural space is evolving in the direction of hematoma, send an expansion control instruction to the expansion control circuit; The expansion control circuit is configured to control the expansion of the expandable body after receiving the aforementioned expansion control instruction.

6. The puncture device according to claim 4, characterized in that: The expandable body is an air bag having a hollow balloon body, and the balloon body is connected to an external inflatable structure so that the balloon body can be inflated and expanded.

7. The puncture device according to any one of claims 2 to 6, characterized in that: The insertion section comprises an inner tube and an outer tube, wherein the inner tube is used as an anesthesia catheter and at least a first electrode is arranged on the inner tube; the outer tube is nested outside the inner tube and can move relative to the inner tube and at least a second electrode is arranged on the outer tube; The outer tube is connected to an external traction controller via a traction structure, and the traction controller drives the traction structure to adjust the relative position of the outer tube and the inner tube, thereby adjusting the distance between the electrodes to adjust the monitoring range.

8. The puncture device according to any one of claims 2 to 6, characterized in that: The insertion section comprises an inner tube and an outer tube, wherein the inner tube serves as an anesthesia catheter, and the outer tube is nested outside the inner tube and can move relative to the inner tube; The outer tube includes a plurality of tube units, adjacent tube units are connected by a dynamic measuring section, and electrodes are respectively arranged on the tube units; the dynamic measuring section is connected to an external adjustment controller, and the adjustment controller is used to change the axial length of the dynamic measuring section in the insertion section catheter to adjust the distance between the plurality of tube units, thereby adjusting the distance between the electrodes to adjust the monitoring range.

9. The puncture device according to claim 8, characterized in that: The dynamic measurement section adopts a flexible airbag tube, the two ends of the airbag tube are respectively fixedly connected to the tube units on both sides, and the airbag tube is connected to the regulating controller through a conveying pipeline, and the regulating controller includes a filling device and a suction device; The adjustment controller is configured to: receive a dynamic measurement adjustment instruction, and when the dynamic measurement adjustment instruction is to increase the monitoring range, control the delivery pipeline to be connected with the filling device to inflate the balloon tube, thereby increasing the axial length of the dynamic measurement section in the insertion section catheter; when the dynamic measurement adjustment instruction is to reduce the monitoring range, control the delivery pipeline to be connected with the suction device to exhaust the balloon tube, thereby reducing the axial length of the dynamic measurement section in the insertion section catheter.

10. A hematoma monitoring and evaluation system, characterized in that: comprising a puncture device and a user terminal, The puncture device is a puncture device with a hematoma monitoring function as described in any one of claims 1 to 9; The user terminal is configured to: receive the analysis result of the electrical impedance analyzer and display the output; and collect the user's operation instruction, and control the electrical impedance measurement structure and / or the electrical impedance analyzer to perform corresponding operations according to the operation instruction.

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