Method and system for determining a progress inserting a needle

Abstract

The invention relates to a system for determining a progress inserting a needle under the skin of a patient, comprising a step (110) of retrieving a force curve, and characterised in that it comprises a step (114) of searching for points of interest representative of a probable position of the needle under the skin of the patient based on the force curve and on a knowledge base (210), a step (112) of calculating a plurality of characteristic metrics of the force curve, a step (122) of classifying by metric based on at least one metric of a database (214) so as to classify the force curve, and a step (120) of determining an insertion position of the needle depending on the points of interest and on the classification by metric. The invention also relates to an associated determining method and associated inserting machine.

Description

[0001] DESCRIPTION

[0002] TITLE OF THE INVENTION: METHOD AND SYSTEM FOR DETERMINING THE PROGRESSION OF NEEDLE INSERTION

[0003] Technical field of the invention

[0004] The invention relates to a method and system for determining the progression of subcutaneous insertion of a needle from an insertion device, for example, insertion into a vein, artery, or nerve of a patient's limb, such as an arm or leg, to perform a cutaneous, venous, arterial, or nerve injection, a venous or arterial puncture, or the placement of a medical device for venous or arterial access. In the remainder of the application, the term "vein" may be used generally to refer to a blood vessel and also to an artery, unless otherwise specified.

[0005] In particular, the invention relates to a method and system for determining insertion progression comprising retrieving data representative of the needle insertion force under the patient's skin captured by a force sensor arranged on the insertion device.

[0006] Technological background

[0007] The applicant has already proposed, notably in patent application WO2015158978, an automated blood sampling device that allows for the automatic insertion of a needle into a patient's vein or artery. Such a device automates blood sampling procedures and includes means for capturing an image of the patient's arm, means for detecting a vein in the captured image, a device for holding the detected vein, a needle, and means for inserting the needle into the detected vein.

[0008] The difficulties encountered, in general, by automatic blood sampling devices lie on the one hand in the problem of the automatic detection of insertion and stoppage of the needle in the vein, artery or nerve of the patient; but also in detecting that the needle is not in the vein, artery or nerve.

[0009] Indeed, determining the progression of needle insertion into the patient's vein, artery, or nerve has two main objectives:

[0010] The goal is to ensure the needle is correctly positioned within the patient's vein, artery, or nerve so that blood is drawn or an injection is administered directly into that vein, artery, or nerve, without complete penetration (transfixation) and without creating a hematoma. The objective of determining the insertion progression is therefore to stop the needle's movement once it is in the vein, artery, or nerve, allowing the blood draw or injection to be performed under optimal conditions.

[0011] The ability to withdraw the needle in case of an anomaly during insertion into the patient's skin is crucial. Specifically, it's essential to detect if the insertion has not been made into the vein, artery, or nerve, but into another tissue, or in the case of transfixion if the needle has not been stopped after insertion into the vein, artery, or nerve. The objective of anomaly detection is linked to patient safety. Solutions have already been proposed for determining the progression of needle insertion within the vein or artery.

[0012] For example, some of these solutions use imaging devices, such as an ultrasound scanner, to determine the depth of the vein and control the automatic insertion based on that depth. The ultrasound scanner can also be used to adjust the control during insertion.

[0013] However, this solution has several drawbacks. In particular, the ultrasound scanner is a costly piece of equipment, which leads to additional expenses for procedures such as blood sampling.

[0014] In addition, the image processing software used to generate the command is highly complex, making it difficult to certify for medical use by the authorities.

[0015] Finally, the use of coupling gel, applied to the patient's skin for the proper functioning of the ultrasound machine, can impact the needle insertion procedure into the patient's vein, artery, or nerve. For example, the needle may become blocked, gel may be introduced into the vein, artery, or nerve during needle insertion, or the mechanical properties of the skin may be altered, which can lead to insertion problems or even injury.

[0016] The inventors therefore sought to improve their system described in the aforementioned patent application by proposing a new solution enabling the determination of the insertion progress of a needle in a vein, artery or nerve of a patient which at least partially overcomes the disadvantages of known solutions.

[0017] Objectives of the invention

[0018] The invention aims to provide a method and system for determining the progression of insertion under the skin of a patient of a needle of an insertion device into a vein, artery or nerve of a patient in a high-performance and safe manner.

[0019] The invention aims in particular to provide a method and a system for determining the progression of needle insertion into a vein, artery or nerve in a limb of a patient, for example an arm or a leg, which can be used alone or in conjunction with an ultrasound scanner to visualize the venous, arterial or nervous network.

[0020] The invention also aims to provide a method and system for determining the progression of needle insertion into a patient's vein, artery, or nerve that is simple and inexpensive.

[0021] Description of the invention

[0022] To this end, the invention also relates to a system for determining the progression of insertion under a patient's skin of a needle of an insertion device, comprising at least one force sensor configured to capture data representative of the insertion force of the needle under the patient's skin so as to obtain a curve formed by the data representative of the needle insertion force, called the force curve, characterized in that it comprises:

[0023] - a module for searching for points of interest based on the force curve and a knowledge base of characteristic elements observable on force curves, said points of interest being representative of a probable position of the needle under the patient's skin,

[0024] - a calculation module for a plurality of metrics characteristic of the force curve,

[0025] - a module for classifying the force curve from said metrics, called classification by metric, from a database of metrics, so as to classify the force curve from at least one metric from said database, - a module for determining a needle insertion position based on points of interest and classification by metric.

[0026] The invention also relates to a method for determining the progression of insertion under the skin of a patient of a needle of an insertion device, comprising a step of retrieving data representative of the insertion force of the needle under the patient's skin captured by at least one force sensor arranged on the insertion device, so as to obtain a curve formed by the data representative of the insertion force of the needle, called the force curve, and characterized in that it comprises:

[0027] - a step of searching for points of interest from the force curve and from a knowledge base of characteristic elements observable on force curves, said points of interest being representative of a probable position of the needle under the patient's skin,

[0028] - a step involving the calculation of a plurality of metrics characteristic of the force curve,

[0029] - a step of classifying the force curve based on said metrics, called classification by metric, from a database of metrics, so as to classify the force curve based on at least one metric from said database,

[0030] - a step of determining a needle insertion position based on points of interest and classification by metric.

[0031] Advantageously, the determination system according to the invention is configured to implement a determination method according to the invention.

[0032] Advantageously, the determination method according to the invention is configured to be implemented by a determination system according to the invention.

[0033] In particular, the determination system may include one or more modules, sub-modules and / or devices enabling the implementation of one, several or part of each step of a determination process according to the invention.

[0034] Throughout the text, the term module refers to a software element, a subset of a software program, which can be compiled separately, either for independent use or to be assembled with other modules of a program, or a hardware element, or a combination of a hardware element and a software subprogram.Such a hardware component can include an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a digital signal processor (DSP), a central processing unit (CPU), a graphics processing unit (GPU), a neural processing unit (NPU), or any equivalent hardware or combination thereof. Generally speaking, a module is therefore a component (software and / or hardware) that performs a function.

[0035] The force sensor is arranged on the insertion device, for example on a needle holder or guide support, so as to allow measurement of the force of insertion of the needle under the skin of a patient.

[0036] The system may include a parameterization module allowing for the modification of classification parameters for the stress curve, range of motion relative to the stress curve, etc. This parameterization module can manage input parameters such as insertion angle, insertion speed, patient characteristics, etc., and determination parameters, allowing, for example, specifying which metrics are taken into account during classification by metric.

[0037] The system and method according to the invention may also include consideration of these classification parameters.

[0038] A system and method for determining insertion progress according to the invention thus allow the monitoring of needle insertion by measuring the insertion force of said needle. The variations in force, measured by a force sensor and processed by the processing module, make it possible to deduce whether the needle insertion is proceeding correctly or if there is an anomaly in the needle insertion.

[0039] The points of interest obtained in said point of interest search step from the force curve and from a knowledge base of characteristic elements observable on force curves, said points of interest being representative of a probable position of the needle under the patient's skin, can be called initial points of interest.

[0040] The system and method according to the invention make it possible in particular to offer a high-performance and low-cost solution for inserting the needle into a patient's vein, artery or nerve and for detecting the progression of insertion under a patient's skin, which can be implemented without an external imaging device to detect this progression, or which can possibly be implemented in addition to such an external imaging device while providing data independent of this external imaging device.

[0041] The detection of all or some of the points of interest and the metrics associated with the force curve can allow for a more precise determination of whether the needle has been inserted into the vein, artery, or nerve. This confirmation can be transmitted as confirmation data to a control device, which can then, for example, deduce that a blood draw or an injection into the vein, artery, or nerve is possible.

[0042] Similar to the comparison of force curve databases, the use of metrics databases allows for the determination of insertion position not only using force data, as in the prior art, but also by comparing this force data with previous insertions whose final outcome is known through the use of metrics. Specifically, by comparing force curve metrics from databases, it is possible to detect whether the force curve used to determine insertion progression closely resembles, due to similar metrics, a previously known force curve that resulted in a successful insertion or, conversely, led to transfixation of the vein, artery, or nerve, or to insertion adjacent to the vein, artery, or nerve.

[0043] These metric data contained in the databases are obtained in particular through prior tests, experiments or simulations, and / or obtained through the implementation of said process according to the invention by one or more determination systems according to the invention.

[0044] An additional step of validating points of interest can advantageously be implemented, in order to ensure for a period of time after identifying a given point of interest that no other is better in the continuation of the force curve, to reduce the risk that points of the force curve have characteristics similar to the points of interest sought.

[0045] Advantageously and according to the invention, the interest point search module is further configured to search for interest points, called complementary interest points, from the force curve and from a force curve database, so as to classify the force curve from at least one force curve from the database, and so as to obtain complementary interest points by comparison with the interest points of at least one force curve from the database according to the classification of the force curve, and in that the needle insertion position determination module is configured to determine said position also as a function of the complementary interest points.

[0046] Advantageously and according to the invention, the method includes a step of searching for points of interest, called complementary points of interest, from the force curve and from a database of force curves, so as to classify the force curve from at least one force curve from the database, and so as to obtain complementary points of interest by comparison with the points of interest of at least one force curve from the database according to the classification of the force curve, and the step of determining a needle insertion position is also carried out according to the complementary points of interest.

[0047] According to this aspect of the invention, the search for points of interest is carried out in different ways to ensure that the detected insertion progress is correct. In particular, the force curve formed by the data representing the needle insertion force as a function of time evolves over time, and the objective is to find the points of interest as early as possible in order to accurately assess the insertion progress. The different methods of searching for points of interest make it possible, in particular, to avoid incorrectly considering a point as a point of interest. For example, if the objective of the search is to find a minimum value in the force curve, a global minimum will be a point of interest, whereas a local minimum should not be considered a point of interest.

[0048] The use of force curve databases makes it possible to determine insertion progress not only using force data, as in the prior art, but also by comparing this force data with previous insertions whose outcome is known. Specifically, by comparing with force curves from databases, it is possible to detect whether the force curve being used to determine insertion progress closely matches a known force curve that resulted in a successful insertion or, conversely, led to transfixation of the vein, artery, or nerve, or to insertion adjacent to the vein, artery, or nerve. Thanks to these database comparisons, force curves can be obtained and processed regardless of the speed, movement, and angle of the needle relative to the skin.

[0049] These force curve data present in the databases are in particular obtained via prior tests, experiments or simulations, and / or obtained via the implementation of said process according to the invention by one or more determination systems according to the invention.

[0050] Initial interest points and supplementary interest points are grouped under the generic term "interest points" in the overall demand when the method of obtaining these interest points does not affect the use of these interest points.

[0051] Advantageously, the system according to the invention is configured for generating a command to move the needle or stop the needle, depending on the determined insertion position and depending on the classification by metric.

[0052] Advantageously and according to the invention, the determination method includes a step of generating a command to move the needle or stop the needle, depending on the determined insertion position and depending on the classification by metric.

[0053] According to this aspect of the invention, the analysis of metrics makes it possible, in particular, to send a command to withdraw the needle from the patient's skin in order to stop the insertion of the needle into the patient's skin. The command to withdraw the needle from the patient's skin can, for example, control a needle retraction device within a needle retraction system according to the invention.

[0054] Advantageously, and according to the invention, the command generation step generates a command to stop the needle insertion if the insertion position exceeds a predetermined maximum depth. Advantageously, the system according to the invention is configured for recording the force curve in a force curve database and / or recording metrics in the metrics database.

[0055] Advantageously and according to the invention, the determination method includes a step of recording the force curve in a force curve database and / or recording the metrics in the metrics database.

[0056] Recording in the different databases allows each execution of the process to be used as useful information for subsequent executions of the process, either during an insertion by the same insertion device, or during an insertion by another insertion device having access to the said database(s).

[0057] Advantageously, the system according to the invention is configured to receive a signal representative of blood detection downstream of the needle, and the generation of a needle movement command or needle stop command is further carried out as a function of said signal representative of blood detection downstream of the needle.

[0058] Advantageously and according to the invention, the determination method includes a step of receiving a signal representative of a detection of blood downstream of the needle, and the step of generating a command to move the needle or stop the needle is further carried out as a function of said signal representative of the detection of blood downstream of the needle.

[0059] According to this aspect of the invention, the signal representing blood detection downstream of the needle can be generated using a flash sensor and allows confirmation or refutation of information indicating that the needle has entered the vein or artery. This signal representing blood detection downstream of the needle is particularly useful during blood sampling.

[0060] Advantageously, the system according to the invention is configured to receive a signal representing a filling rate of an injection or sampling tube, and the generation of a needle movement or needle stop command is further carried out as a function of said signal representing the filling rate of the injection or sampling tube.

[0061] Advantageously and according to the invention, the determination method includes a step of receiving a signal representative of a filling rate of an injection or sampling tube, and the step of generating a command to move the needle or stop the needle is further carried out as a function of said signal representative of the filling rate of the injection or sampling tube.

[0062] According to this aspect of the invention, the signal representing the filling rate of the injection or sampling tube can be relevant additional information for determining the command to be generated. In particular, in the case of a perfectly functioning filling of a sampling tube or emptying of an injection tube followed by a stoppage of the filling or emptying process, the generated command can be to move the needle until the filling or injection resumes. For example, a forward or backward movement can be commanded to return to the center of the vein, artery, or nerve in the event of a stoppage in tube filling or product injection.

[0063] Advantageously and according to the invention, the representative data of the insertion force are retrieved periodically, and in that the step(s) of searching for points of interest and classification by metrics are executed periodically.

[0064] According to this embodiment of the invention, the insertion progress can be determined periodically to obtain a precise and rapid determination of the insertion progress. In particular, the data retrieval period and the period for searching for points of interest and classifying by metrics are advantageously on the order of milliseconds. The data retrieval window is advantageously on the order of seconds.

[0065] Advantageously, and according to this latter aspect of the invention, the search for points of interest includes calculating an average of the representative data of the needle insertion force contained in the sliding window. According to this aspect of the invention, the periodic search takes in particular the form of a sliding average allowing the smoothing of the force data obtained.

[0066] Advantageously, and according to the invention, each search for points of interest is configured to search for at least one of the following points of interest:

[0067] - a first point of interest relating to contact of the needle on the skin, - a second point of interest relating to a release of the force of insertion of the needle,

[0068] - a third point of interest relating to an optimal stopping position for the needle,

[0069] - a fourth point of interest relating to a transfixion.

[0070] According to this aspect of the invention, these points of interest are the expected points that can be found during needle insertion procedures. Transfixion, which involves passing through the vein, artery, or nerve and traversing the second wall after successful insertion, must be avoided but must also be detectable quickly to prevent any problems with sampling or injection.

[0071] Advantageously, and according to the invention, the search for points of interest includes a step of detecting each point of interest comprising:

[0072] - a substep verifying a condition whereby each point of interest can only be detected once for each force curve,

[0073] - a preliminary sub-step of defining an order for detecting points of interest,

[0074] - a sub-step of analyzing the variations in force over time according to the points of interest already detected and the predefined detection order, by using force amplitude thresholds or time thresholds.

[0075] According to this aspect of the invention, the system and the method make it possible to ensure that the points of interest are detected in the expected order and that the force variations are consistent with the expected values.

[0076] Advantageously, the system according to the invention is configured for receiving external force curve data intended to supplement the force curve database and / or external metric data intended to supplement the metric curve database.

[0077] Advantageously and according to the invention, the determination method includes a step of receiving external force curve data intended to supplement the force curve database.

[0078] Advantageously and according to the invention, the determination method includes a step of receiving external metric data intended to supplement the metric database.

[0079] According to this aspect of the invention, these steps allow for the updating of database data in order to continuously improve the performance of the process.

[0080] Advantageously, the system according to the invention is configured for sending force curve data to one or more external force curve databases and / or metric data to one or more external metric databases.

[0081] Advantageously and according to the invention, the determination method includes a step of sending force curve data to one or more external force curve databases and / or metric data to one or more external metric databases.

[0082] Advantageously and according to the invention, the calculation of a plurality of characteristic metrics of the force curve includes the calculation of at least one of the following metrics:

[0083] time difference between two points of interest,

[0084] difference in amplitude between two points of interest,

[0085] slope between two points of interest,

[0086] area under the curve, coefficient of skewness of the curve,

[0087] kurtosis of the curve,

[0088] value of the maximum of the force curve.

[0089] According to this aspect of the invention, these metrics allow the force curve to be characterized by comparison to a metric database and allow in particular a second step of searching for points of interest by using this metric database for comparison with the metrics of the force curve.

[0090] The metrics correspond to known characteristics relating to the insertion of a needle, and allow us to ensure that the insertion corresponds to a normal insertion, a transfixation or an insertion next to the vein, artery or nerve.

[0091] In particular, the metrics correspond to events during needle insertion, for example, crossing the first layer of skin epidermis, crossing another different layer of epidermis, crossing the first venous or arterial wall or entering a nerve, crossing the second venous or arterial wall or nerve, etc.

[0092] Advantageously, and according to the invention, the needle is intended to be inserted into a patient's vessel, and in that the pre-established force curve classifications include at least:

[0093] - an initial classification of force curves corresponding to needle insertion into the vessel,

[0094] - a second force curve classification corresponding to needle insertion next to the vessel,

[0095] - a third classification of force curve corresponding to a complete passage of the needle through the vessel,

[0096] - a fourth force curve classification corresponding to an insertion in progress before contact with a first wall of the vein or finalized before contact with the first wall of the vein.

[0097] According to this aspect of the invention, the force curve is compared to three types of classifications which are present in the force curve database and which allow detection of an insertion in the vessel, an insertion beside and a transfixion by comparison to these curves in the force curve database.

[0098] Advantageously, the system according to the invention is configured for force curve classification comprising comparing the force curve with a plurality of force curves in the database, selecting the force curve from the database that most closely matches the force curve to be classified based on predefined metrics, and classifying the force curve to be classified based on the classification of said force curve from the closest database.

[0099] Advantageously and according to the invention, the force curve classification step includes a substep of comparing the force curve with a plurality of force curves from the database, a substep of selecting the force curve from the database closest to the force curve to be classified from predefined metrics, and a substep of classifying the force curve to be classified from the classification of said force curve from the closest database.

[0100] According to this aspect of the invention, the classification is carried out by comparison with the closest curve among the curves in the force curve database.

[0101] The invention also relates to an automatic or semi-automatic needle insertion machine for a patient's limb, comprising:

[0102] - equipment for receiving the patient's limb to be punctured, - a mechatronic assembly carrying a needle holder adapted to receive a needle intended to be inserted into a vein of the patient, - a control unit configured to control said mechatronic assembly and said needle holder and to control the insertion of the needle into the patient's skin, characterized in that it further comprises a system for determining a progression of insertion under the skin of the needle according to the invention.

[0103] The invention also relates to a method for determining the progression of insertion under the skin of a patient of a needle of an insertion device, a system for determining the progression of insertion under the skin of a patient of a needle of an insertion device and a needle insertion machine characterized in combination by all or part of the characteristics mentioned above or below.

[0104] List of figures

[0105] Other objects, features and advantages of the invention will become apparent from the following description, given by way of non-limiting example only, and which refers to the accompanying figures in which:

[0106] [Fig. 1] is a schematic view of a device for inserting a needle into a patient's vein, artery or nerve, which can be used in conjunction with a system or method for determining the progression of insertion under a patient's skin of a needle according to an embodiment of the invention.

[0107] [Fig. 2] is a schematic representation of a method for determining the progression of insertion under the skin of a patient of a needle of an insertion device, according to an embodiment of the invention.

[0108] [Fig. 3] is a schematic graph representing a first evolution of data representative of an insertion force, measured by a force sensor of a determination system according to an embodiment of the invention.

[0109] [Fig. 4] is a table representing different metrics that can be used in a method for determining the progression of insertion under the skin of a patient of a needle of an insertion device, according to an embodiment of the invention.

[0110] [Fig. 5] is a schematic representation of a method for determining the progression of insertion under the skin of a patient of a needle of an insertion device, according to an embodiment of the invention. Detailed description of an embodiment of the invention. In the figures, the scales and proportions are not strictly respected for the purposes of illustration and clarity.

[0111] In addition, identical, similar or analogous elements are designated by the same references in all figures.

[0112] Figure 1 schematically represents a device 10 for inserting a needle into a vein, artery, or nerve of a patient, such as can be used in a determination method or a determination system according to an embodiment of the invention. The insertion device 10 comprises a needle 12 for insertion into a vein, artery, or nerve of a patient by passing through the patient's skin. The needle is, for example, inserted into a limb of the patient, such as an arm or leg, particularly into the cubital fossa (also called the antecubital fossa or ulnar fossa) of the patient's arm, and allows, for example, blood sampling or injection. The needle extends longitudinally along a preferred axis, referred to as the needle axis 14, corresponding to the axis of penetration of the needle into the patient's skin.

[0113] The needle 12 is carried by a needle holder 16 of the insertion device 10, generally extending along the axis 14 of the needle. The needle holder 16 includes means 18 for holding the needle in place and includes a collection or injection tube 20 for retrieving the drawn blood or storing the fluid to be injected. The tube 20 is carried by a tube holder 22 of the needle holder 16. The needle holder 16 may also carry a needle retraction device (not shown) of the insertion device 10, configured to withdraw the needle from the patient's skin during needle insertion, if a command to withdraw the needle from the skin is received. The needle may, for example, be retracted into the needle holder 16 by this needle retraction device.

[0114] The insertion device 10 also includes a guide support 24, configured to guide the needle according to needle insertion control instructions. For example, the guide support 24 can be mounted on a mechatronic system with multiple axes of freedom, such as a robotic arm (not shown), allowing the guide support 24 to move in the directions necessary for needle insertion (at a minimum, translation along the needle axis, preferably translation along multiple axes and rotations about one or more axes).

[0115] The needle insertion device 10 is equipped with a force sensor 30 of the determination system configured to measure data representative of the needle insertion force through the patient's skin until entry into the patient's vein, artery, or nerve, and a data processing module 34. According to an embodiment of the invention (not shown), the insertion force is acquired by two sensors at a configurable frequency (between 100 and 1000 Hz).

[0116] The guide support 24 and the needle holder 16 are connected by a pivot link 36 allowing the direct transmission of the force exerted by the tissues on the needle 12 to the force sensor 30.

[0117] The force sensor 30 is arranged in the guide support 24 and opposite a bearing surface 32 attached to the needle holder 16. Applying a force to the needle, particularly when it is in contact with or inserted into the patient's skin, results in the application of a force by the bearing surface 32 on the force sensor, representative of the needle insertion force, preferably proportional to it. The detection device thus enables the measurement of data representative of the needle insertion force in the patient's skin. The data recorded by the sensor can be processed by a data processing module 34 for representative insertion force data, arranged in the guide support 24 or in a remote processing system.The data processing module 34 can advantageously be part of the determination system and thus implement the determination process according to an embodiment of the invention.

[0118] Figure 2 schematically represents a method for determining the progression of insertion under the skin of a patient of a needle of an insertion device, according to an embodiment of the invention.

[0119] The process 100 includes a step 110 of retrieving data representative of the force of insertion of the needle under the patient's skin captured by a force sensor arranged on the insertion device.

[0120] The process then includes a step 112 of calculating a plurality of metrics characteristic of a curve formed by the representative data of the needle insertion force, for example as a function of time, called the force curve. These metrics are mathematical characteristics used to characterize the shape of the force curve, and can be, for example:

[0121] a time difference between two points of interest, a difference in amplitude between two points of interest, the slope between two points of interest,

[0122] the area under the curve,

[0123] the coefficient of skewness of the curve,

[0124] the kurtosis of the curve,

[0125] value of the maximum of the force curve.

[0126] Some metrics are only accessible after one or more points of interest on the force curve have been determined, as described below. Furthermore, because the force curve is continuously updated based on new force data representing the insertion force collected over time, these metrics may change over time.

[0127] The procedure also includes a step 114 for identifying points of interest, called initial points of interest, from the force curve and from a knowledge base 210 of characteristic features observable on force curves. These initial points of interest are representative of a probable position of the needle under the patient's skin. The knowledge base includes, for example, characteristic values ​​of force, force variation, or rate of force variation typically associated with needle insertion in the target area of ​​the patient. These initial points of interest allow for a preliminary estimation of the insertion progression.

[0128] This step includes, in particular:

[0129] a substep 114a of verifying a condition whereby each point of interest can only be detected once for each force curve,

[0130] a preliminary sub-step 114b defining an order for detecting points of interest,

[0131] a substep 114c of analysis of force variations over time as a function of points of interest already detected and of the predefined detection order, by the use of force amplitude thresholds or time thresholds.

[0132] The process also includes a step 116 of validation of said points of interest according to predetermined validation parameters, to obtain validated points of interest.

[0133] The process also includes a step 118 of searching for complementary points of interest from a force curve and from a base 212 of force curve data, so as to classify the force curve from at least one force curve in the database, and so as to obtain complementary points of interest by comparison with the points of interest of at least one force curve in the database according to the classification of the force curve.

[0134] This step allows the force curve to be compared with known force curves stored in the database, so as to allow a better determination of points of interest.

[0135] Figure 3 schematically represents a graph 300 showing a curve of data representing an insertion force, measured by a force sensor arranged on an insertion device 10 according to an embodiment of the invention. The graph expresses the measured insertion force F as a function of time t.

[0136] The graph represents a theoretical curve 302 of representative data of the insertion force measured by a force sensor as described with reference to Figure 1, and used by a determination method as described with reference to Figure 2.

[0137] The two interest point search steps of the determination process are configured to search for at least the following interest points:

[0138] a first point A of interest relating to contact of the needle on the skin,

[0139] a second point B of interest relating to a release of the force exerted by the needle insertion,

[0140] a third point C of interest relating to an optimal stopping position of the needle,

[0141] a fourth point D of interest relating to a transfixation of a vein, artery or nerve.

[0142] Within the curves, it is possible to identify up to four main events: contact between the needle and the skin, the main tissue relaxation, the presence of the needle with its bevel in the vein, artery, or nerve, and the beginning of transfixation (in cases of transfixation). It should be noted that these last two events can correspond to the same point. The properties (amplitude, maximum, minimum, shapes, such as plateaus, etc.) of these events depend on several parameters that can be associated with the characteristics of the puncture (type of needle, speed and angle of insertion, needle movements) or with the patient's physiological characteristics (skin elasticity, depth and width of the vein, artery, or nerve, etc.).

[0143] Returning to Figure 2, the process also includes a step 120 of determining a needle insertion position based on the initial and additional points of interest.

[0144] The process also includes a step 122 of classifying the force curve based on said metrics, referred to as metric classification, using a database 214 of metrics, so as to classify the force curve based on at least one metric from said database. This metric comparison provides additional information from the force curve and allows determining whether the current force curve corresponds to a known classification. The use of metrics based on the force curve between these points of interest makes it possible to differentiate between an insertion and a successful puncture. Metric classification thus allows for refining the determination of the insertion position by providing additional information from the metrics.

[0145] Step 122 of force curve classification includes a substep of comparing the force curve with a plurality of force curves in the database, a substep of selecting the force curve in the database closest to the force curve to be classified from predefined metrics, and a substep of classifying the force curve to be classified from the classification of said force curve in the closest database.

[0146] For example, when the needle is intended to be inserted into a patient's vessel, and the pre-established force curve classifications include at least:

[0147] an initial classification of force curves corresponding to needle insertion into the vessel,

[0148] a second force curve classification corresponding to needle insertion next to the vessel,

[0149] a third classification of force curve corresponding to a complete passage of the needle through the vessel,

[0150] a fourth force curve classification corresponding to an insertion in progress before contact with a first wall of the vein or completed before contact with the first wall of the vein.

[0151] Data representing insertion force are retrieved periodically, for example on the order of every millisecond, and the steps of searching for points of interest and classifying by metrics are executed periodically, the objective being to enable rapid command generation based on the determined insertion stage.

[0152] The process finally includes a step 124 of generating a command to move the needle or stop the needle, depending on the determined insertion position and the classification by metric.

[0153] The command generation step 124 may also depend on other data. In particular, when using data from a blood sample, the process may include a step 126 of receiving a signal representing blood detection downstream of the needle. The subsequent step of generating a command to move or stop the needle is further based on this signal representing blood detection downstream of the needle. This signal is transmitted by a sensor known as a "Flash" sensor and ensures proper blood flow during a blood draw.

[0154] The method may also include a step 128 of receiving a signal representative of a filling rate of an injection or sampling tube, the step of generating a command to move the needle or stop the needle, being further carried out according to said signal representative of the filling rate of the injection or sampling tube.

[0155] The procedure may also include a step 129 of receiving a signal representative of the maximum insertion depth reached. This maximum insertion depth parameter is generally predetermined and may depend on known anatomical data and / or data acquired during previous insertions.

[0156] The data obtained following insertion can be recorded for future use. In particular, the process may include a step 130 of recording the force curve in the force curve database and / or recording the metrics in the metrics database.

[0157] In addition, the databases can be fed and / or can feed external databases, so as to allow data sharing with external determination systems, for example installed with several injection devices distributed at different locations.

[0158] In particular, the method may include a step 132 of receiving external force curve data to supplement the force curve database and / or external metrics data to supplement the metrics curve database. The method may also include a step 134 of sending external force curve data to one or more external force curve databases and / or external metrics data to one or more external metrics databases.

[0159] Figure 4 schematically represents a table comprising various metrics that can be used in a method for determining the progression of subcutaneous insertion of a needle from an insertion device in a patient, according to an embodiment of the invention. These metrics can be divided into three categories: differences (temporal and amplitude), slopes, and asymmetries. They allow for the separate and joint description of the increasing and decreasing portions (after needle-skin contact) of the force curve.

[0160] The fit metrics are estimated from the fitting of two mathematical models to the force curves between Ps and Pm. The first model, a third-order polynomial, has the advantage of being simple to fit (linear minimization), but its parameters are difficult to interpret. The second model is a modified Gaussian that takes into account the asymmetry between the growth and decay of the curve. The parameter estimation is more complex (non-linear minimization), but the parameters are interpretable (amplitude, center, width, and asymmetry of the peak formed by the growth and decay of the force curve). The equations for these two models are given below:

[0161] Third-order polynomial:

[0162] [Math. 1]

[0163] y

[0164]

[0165] (0, t) = a Q t 3 + a ± t 2 + a2t + a3

[0166] Modified Gaussian:

[0167] [Math. 2]

[0168] i / tn t 2

[0169] y

[0170]

[0171] (0,t) = se Aff-kO / ô / Metrics allow us to determine different characteristics of the curves, in which:

[0172] P s is the point associated with the beginning of the growth of the force curve, P M is the point associated with the maximum of the force curve,

[0173] P m is the point associated with the minimum of the force curve (after P M ), - The exponent 't' associated with a point indicates the time associated with that point, - The exponent 'a' associated with a point indicates the amplitude (the force) associated with that point,

[0174] - A(P x ,P y ) is the area under the curve between the points P x and P y ,

[0175] - y is the measured force,

[0176] N is the number of points and n is the index of the current point,

[0177] S is the summation operator,

[0178] s is the coefficient of skewness of the curve, k is the kurtosis of the curve,

[0179] mi is the central moment of order i,

[0180] <j est l’écart-type.

[0181] Figure 5 schematically represents a system 500 for determining the progression of needle insertion under a patient's skin. This system consists of an insertion device 510 comprising at least one force sensor 530 configured to capture data representative of the needle's insertion force under the patient's skin, thus obtaining a curve formed by the representative data of the needle's insertion force, referred to as the force curve. The sensor is carried by the insertion device 510, which may, for example, be an insertion device as described previously with reference to Figure 1. The insertion device forms a mechatronic assembly carrying a needle holder adapted to receive a needle intended for insertion into a patient's vein. The patient's limb may be positioned on a limb receiving device for the puncture.

[0182] The 500 determination system also includes a 514 module for searching for points of interest, called initial points of interest, from the force curve and from a knowledge base of characteristic elements observable on force curves, said initial points of interest being representative of a probable position of the needle under the patient's skin.

[0183] The 500 determination system also includes a 512 module for calculating a plurality of metrics characteristic of the force curve.

[0184] The 500 determination system also includes a 522 module for classifying the force curve from said metrics, called classification by metric, from a database of metrics, so as to classify the force curve from at least one metric from said database.

[0185] The 500 determination system also includes a 520 module for determining a needle insertion position based on initial points of interest and classification by metric.

[0186] The 500 determination system also includes modules and sub-modules not shown configured to implement all or part of the process as described with reference to Figure 2.

[0187] These modules can be integrated into a control unit configured to control said mechatronic assembly and said needle holder and to control the insertion of the needle into the patient's skin.

[0188] The complete insertion device, control unit and receiving equipment for the patient limb to be punctured form an automatic or semi-automatic needle insertion machine for a patient limb.

[0189] In particular, the 514 interest point search module of the 500 determination system can also be further configured to search for points of interest, referred to as complementary points of interest, from the force curve and from a force curve database. This allows the force curve to be classified based on at least one force curve in the database, and complementary points of interest to be obtained by comparison with the points of interest in at least one force curve in the database, according to the force curve classification. Furthermore, the needle insertion position determination module can be configured to determine said position also based on the complementary points of interest. The 500 determination system thus enables the execution of step 118, the search for complementary points of interest, as described above.

[0190] The 500 determination system can also be configured to generate a needle movement or needle stop command, based on the determined insertion position and the metric classification. The 500 determination system thus enables the execution of step 124, which generates a needle movement or needle stop command as described above.

[0191] The 500 determination system can also be configured to record the force curve in a force curve database and / or to record metrics in a metrics database. The 500 determination system thus allows the execution of recording step 130 as described above.

[0192] The 500 determination system can also be configured to receive a signal representing blood detection downstream of the needle, and the generation of a needle movement or needle stop command is further performed based on this representative blood detection signal. The 500 determination system thus enables the execution of step 126, which involves receiving a representative blood detection signal downstream of the needle as described above.

[0193] The 500 determination system can also be configured to receive a signal representing the fill level of an injection or sampling tube, and the generation of a needle movement or needle stop command is further performed based on this signal representing the fill level of the injection or sampling tube. The 500 determination system thus allows the execution of step 128, which involves receiving a signal representing the fill level of an injection or sampling tube. The 500 determination system can also be configured to retrieve representative insertion force data periodically, and the interest point search module can be configured to periodically search for points of interest, while the metric classification module can be configured to periodically classify the force curve.The 500 determination system thus makes it possible to implement the periodic recovery as described above in connection with the determination process already described.

[0194] The 500 determination system can also be configured so that each point of interest search is set up to search for at least one of the following points of interest:

[0195] - a first point (A) of interest relating to contact of the needle on the skin,

[0196] - a second point (B) of interest relating to a relaxation of the needle insertion force,

[0197] - a third point (C) of interest relating to an optimal stopping position of the needle,

[0198] - a fourth point (D) of interest relating to a transfixion. The 500 determination system thus allows the use of inflection points such as those described above in connection with the associated determination procedure.

[0199] The 500 determination system can also be configured so that the point of interest search module is set up to detect each point of interest, including:

[0200] - a verification of a condition according to which each point of interest can only be detected once for each force curve, - a prior definition of an order of detection of the points of interest, - an analysis of the variations of force over time as a function of the points of interest already detected and the predefined order of detection, by the use of force amplitude thresholds or time thresholds.

[0201] The 500 determination system thus allows the execution of substeps 114a to 114c as described above.

[0202] The 500 determination system can also be configured to receive external force curve data to supplement the force curve database and / or external metric data to supplement the metric curve database.

[0203] The 500 determination system thus allows the execution of step 132 of receiving external data as described above.

[0204] The 500 determination system can also be configured to send force curve data to one or more external force curve databases and / or metric data to one or more external metric databases.

[0205] The 500 determination system thus allows the execution of step 134 of sending external data as described above.

[0206] The 500 determination system can also be configured to calculate, via the 512 metric plurality calculation module, a plurality of metrics characteristic of the force curve, including the calculation of at least one of the following metrics:

[0207] time difference between two points of interest,

[0208] difference in amplitude between two points of interest,

[0209] slope between two points of interest,

[0210] area under the curve,

[0211] curve skewness coefficient,

[0212] kurtosis of the curve,

[0213] - value of the maximum of the force curve.

[0214] The 500 determination system can also be configured so that the needle is intended to be inserted into a patient vessel, and so that the pre-established force curve classifications include at least:

[0215] - an initial classification of force curves corresponding to needle insertion into the vessel,

[0216] - a second force curve classification corresponding to needle insertion next to the vessel, - a third force curve classification corresponding to complete passage of the needle through the vessel

[0217] - a fourth force curve classification corresponding to an insertion in progress before contact with a first wall of the vein or finalized before contact with the first wall of the vein.

[0218] The 500 determination system can also be configured with a force curve classification that includes comparing the force curve with a plurality of force curves in the database, selecting the force curve from the database that is closest to the force curve to be classified based on predefined metrics, and classifying the force curve to be classified based on the classification of said force curve from the closest database.

Claims

DEMANDS 1. A system for determining the progression of needle insertion under a patient's skin of an insertion device (10), comprising at least one force sensor (30) configured to capture data representative of the needle insertion force under the patient's skin so as to obtain a curve formed by the data representative of the needle insertion force, called the force curve, characterized in that it comprises: - a module (514) for searching for points of interest from the force curve and from a knowledge base of characteristic elements observable on force curves, said points of interest being representative of a probable position of the needle under the patient's skin, - a module (512) for calculating a plurality of metrics characteristic of the force curve, - a module (522) for classifying the force curve from said metrics, called classification by metric, from a database of metrics, so as to classify the force curve from at least one metric from said database, - a module (520) for determining an insertion position of the needle as a function of the points of interest and the classification by metric.

2. A determination system according to claim 1, characterized in that the interest point search module is further configured for a search for interest points, called complementary interest points, from the force curve and from a force curve data base (212), so as to classify the force curve from at least one force curve from the data base (212), and so as to obtain complementary interest points by comparison with the interest points of at least one force curve from the data base (212) according to the classification of the force curve, and in that the needle insertion position determination module (520) is configured to determine said position also as a function of the complementary interest points.

3. A determination system according to claim 1 or 2, characterized in that it is configured for generating a command to move the needle or stop the needle, depending on the determined insertion position and depending on the classification by metric.

4. A determination system according to any one of claims 1 to 3, characterized in that it is configured for recording the force curve in a force curve database and / or recording metrics in the metrics database.

5. A determination system according to claim 7, characterized in that it is configured for receiving a signal representative of blood detection downstream of the needle, and that the generation of a command to move the needle or stop the needle is further carried out as a function of said signal representative of blood detection downstream of the needle.

6. A determination system according to any one of claims 4 or 5, characterized in that it is configured for receiving a signal representative of a filling rate of an injection or sampling tube, and that the generation of a needle movement command or needle stop command is further carried out as a function of said signal representative of the filling rate of the injection or sampling tube.

7. A determination system according to any one of claims 1 to 6, characterized in that the representative data of the insertion force are retrieved periodically, and in that the interest point search module is configured to periodically search for interest points and in that the metric classification module is configured to periodically classify the force curve.

8. A determination system according to any one of claims 1 to 7, characterized in that each search for points of interest is configured to search for at least one of the following points of interest: - a first point (A) of interest relating to contact of the needle on the skin, - a second point (B) of interest relating to a relaxation of the needle insertion force, - a third point (C) of interest relating to an optimal stopping position of the needle, - a fourth point (D) of interest relating to a transfixion.

9. A determination system according to any one of claims 1 to 8, characterized in that the interest point search module is configured for the detection of each interest point comprising: - a verification of a condition according to which each point of interest can only be detected once for each force curve, - a prior definition of an order of detection of the points of interest, - an analysis of the variations of force over time as a function of the points of interest already detected and the predefined order of detection, by the use of force amplitude thresholds or time thresholds.

10. A determination system according to any one of claims 1 to 9, characterized in that it is configured for receiving external force curve data intended to supplement the force curve data base (212) and / or external metric data intended to supplement the metric curve data base (214).

11. A determination system according to any one of claims 1 to 10, characterized in that it is configured for sending force curve data to one or more external force curve databases and / or metric data to one or more external metric databases.

12. A determination system according to any one of claims 1 to 11, characterized in that it is configured for calculating a plurality of characteristic metrics of the force curve, comprises the calculation of at least one of the following metrics: time difference between two points of interest, difference in amplitude between two points of interest, slope between two points of interest, area under the curve, curve skewness coefficient, kurtosis of the curve, - value of the maximum of the force curve.

13. A determination system according to any one of claims 1 to 12, characterized in that the needle is intended to be inserted into a vessel of the patient, and in that the pre-established force curve classifications include at least: - a first force curve classification corresponding to an insertion of the needle into the vessel, - a second force curve classification corresponding to needle insertion next to the vessel, - a third classification of force curve corresponding to a complete passage of the needle through the vessel, - a fourth force curve classification corresponding to an insertion in progress before contact with a first wall of the vein or finalized before contact with the first wall of the vein.

14. A determination system according to any one of claims 1 to 13, characterized in that it is configured for a force curve classification comprising a comparison of the force curve with a plurality of force curves from the database, a selection of the force curve from the database closest to the force curve to be classified from predefined metrics, and a classification of the force curve to be classified from the classification of said force curve from the closest database.

15. A method for determining the progression of insertion under the skin of a patient of a needle from an insertion device (10), comprising a step (110) of retrieving data representative of the insertion force of the needle under the patient's skin captured by at least one force sensor (30) arranged on the insertion device (10), so as to obtain a curve formed by the data representative of the insertion force of the needle, called the force curve, and characterized in that it comprises: - a step (114) of searching for points of interest from the force curve and from a basis (210) of knowledge of the characteristic elements observable on force curves, said points of interest being representative of a probable position of the needle under the patient's skin, - a step (112) of calculating a plurality of metrics characteristic of the force curve, - a step (122) of classifying the force curve from said metrics, called classification by metric, from a database (214) of metrics, so as to classify the force curve from at least one metric from said database (214), - a step (120) of determining an insertion position of the needle according to the points of interest and the classification by metric.

16. Automatic or semi-automatic needle insertion machine for a patient's limb comprising: - equipment for receiving the patient's limb to be punctured, - a mechatronic assembly (10) carrying a needle holder adapted to receive a needle intended to be inserted into a vein of the patient, - a control unit configured to control said mechatronic assembly and said needle holder and to control the insertion of the needle into the patient's skin, characterized in that it further comprises a system (500) for determining a progression of insertion under the skin of the needle according to any one of claims 1 to 14.

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