Safety device for emergency shutoff of an extracorporeal blood system with a needle dislocation detection mechanism and a shutoff mechanism

Abstract

The invention relates to a shut-off device for an extracorporeal blood treatment machine, preferably a dialysis machine, for triggering an emergency shut-off of an extracorporeal blood line system of the extracorporeal blood treatment machine in the event of needle dislocation. The shut-off device comprises a shut-off mechanism (8) adapted to reduce or shut off a blood flow through a line (7, 9) of the extracorporeal blood treatment machine, and an actuating / triggering device (11) adapted to actuate / trigger the shut-off mechanism (8) when a venous patient access / venous patient connection (10), preferably an access cannula, and an arterial patient access / arterial patient connection (6), preferably an access cannula, of the extracorporeal blood line system, the venous patient access / venous patient connection (10) and the arterial patient access / arterial patient connection (6) having a predetermined relative starting position relative to one another or being set such that they are moved out of or are moved out of the predetermined relative starting position.

Description

Technical Field

[0001] The present invention relates to a shutoff device for an extracorporeal blood treatment machine, in particular a dialysis machine, which actuates or triggers a shutoff mechanism in response to a relative movement of two patient accesses, in particular access cannulas, out of a predetermined relative position, in order to shut off or reduce blood flow through a (blood) line of the extracorporeal blood treatment machine. In other words, the present invention relates to an extracorporeal blood line system for an extracorporeal blood treatment machine (dialysis machine), comprising a safety system / safety device (comprising a needle dislocation detection device, in particular a relative position detection device / position detection device, and a shutoff device). The safety system / safety device responds to a change in the relative position between the venous patient access / venous patient connection and the arterial patient access / arterial patient connection of the extracorporeal blood line system (the patient access / patient connection being the patient connection of the blood line system itself). When a defined or predeterminable (detectable) value for the change in the relative position of the venous patient access / venous patient connection and the arterial patient access / arterial patient connection of the extracorporeal blood line system exists, the safety system / safety device at least partially (at least in one position) shuts off or reduces the flow cross section thereof. Background Art Background of the Invention

[0003] Dialysis, particularly hemodialysis, hemofiltration and hemodiafiltration, is the most common treatment for renal failure and requires frequent and regular treatment by the patient, either in a hospital or at home by the patient himself.

[0004] During dialysis treatment, arterial access is provided via an arterial access cannula (arterial connection of the extracorporeal blood tubing system) and venous access is provided via a venous access cannula (venous connection of the extracorporeal blood tubing system) to connect the patient to the dialysis machine. For this purpose, an indwelling venous cannula or indwelling venous catheter is used, wherein a plastic tube or indwelling tube is inserted into the patient's vein via a metal cannula / insertion needle and remains in the patient's vein as a (patient) access after the metal cannula / insertion needle is removed. Such indwelling venous cannulas are well known in the prior art.

[0005] When the venous patient access, or more specifically the plastic tubing retained in the vein, becomes loose during dialysis treatment and partially or completely slips out of the patient's blood vessel / vein, this is known as venous needle dislocation (VND). This presents significant difficulties and risks for the patient. In this case, the blood flowing through the dialysis machine does not flow back into the patient's circulation but is instead pumped into the surrounding environment, particularly by the blood pump of the hemotherapy machine. In the case of VND (venous needle dislocation), the average patient can lose up to 50% of their total blood volume within five minutes, and two minutes is enough to significantly impair the patient's vital signs. Therefore, VND (venous needle dislocation) must be identified as quickly as possible. Depending on the reaction time, it can result in relatively minor blood loss, an increased risk of infection, irreversible brain damage, or even death. In addition to the physical and psychological consequences for the patient, the required blood bags and subsequent treatment also incur high costs. Especially for home dialysis and nocturnal treatments, where the patient is mostly asleep, VND (venous needle dislocation) is critical because the patient himself cannot notice it, cannot react as promptly as possible, and cannot draw attention to it.

[0006] A particular challenge is that VND (venous needle dislocation) can occur at any time. Although some risk factors are known, such as patient anxiety or mental impairment, and the onset of muscle spasms during the treatment, VND (venous needle dislocation) can still occur under ideal conditions and is therefore difficult to predict.

[0007] Existing technology

[0008] To reduce the risk of VND (venous needle dislocation), there are guidelines regarding the manner and methods of placing and securing access points. Furthermore, there are solutions that can detect the occurrence of VND (venous needle dislocation) and trigger an alarm, and if necessary, shut down the blood pump of the blood treatment machine or reduce the flow cross-section of the extracorporeal blood tubing system.

[0009] This solution usually involves pressure monitoring in the venous line or in the venous access, for example using the VAM system from Fresenius Medical Care, which is standardly installed in dialysis machines. However, monitoring changes in venous pressure is notoriously unstable, especially since the pressure can fluctuate drastically depending on a variety of factors. Consequently, some VNDs (venous needle dislocations) are only recognized with a delay, which is why the patient may have lost a significant amount of blood before the alarm is triggered. Furthermore, it can happen that, for example due to flow resistance on the needle or its fixing material and in the event of incomplete loosening of the needle, the pressure drop is so low that it is not recognized as a VND (venous needle dislocation) and the alarm is not triggered at all.

[0010] Another solution is to detect leaks at the access point using leak or moisture sensors attached at that location. These sensors monitor the loss of blood into the surrounding environment, such as the VenAcc from Fresenius Medical Care and the Redsense from Redsense Medical. These devices have disposable sensor pads that adhere to the needle and can detect even small amounts of leaking liquid. However, these devices incur considerable additional costs, as they require expensive additional equipment and disposable components, and human error cannot be ruled out.

[0011] Therefore, known solutions cannot detect VND (venous needle dislocation) with 100% reliability. Furthermore, due to the high probability of false alarms due to misuse or incorrect operation, or due to overly narrow thresholds, venous alarms are often simply disabled, resulting in the possibility that VND (venous needle dislocation) may not be detected in time despite the alarm sounding. Furthermore, such known systems are very complex because (pressure / humidity) sensors must be attached, and their signals are processed in the device's own control system. This makes the device or the extracorporeal blood tubing system more expensive as a disposable system. Summary of the Invention

[0012] The object of the present invention is therefore to provide an extracorporeal blood line system with a (system-specific) safety device, in particular in the event of a VND (venous needle dislocation), which in particular overcomes the aforementioned disadvantages of existing systems / safety devices and, in particular, allows, for example, a reliable and rapid detection of a VND (venous needle dislocation) and the fastest and most reliable possible interruption / reduction of blood flow. Furthermore, the extracorporeal blood line system or its safety device for preventing blood loss, for example in the event of a VND (venous needle dislocation), should be as simple and inexpensive as possible.

[0013] This object is achieved by a safety device for an extracorporeal blood line system or an extracorporeal blood line system of / for an extracorporeal blood treatment machine according to the invention.

[0014] For a better understanding it should be noted that the terms "upstream" and "downstream" used hereinafter are always considered with reference to the direction of blood flow.

[0015] This object is achieved in particular by a safety device according to the invention, comprising a needle dislocation detection mechanism and a shut-off mechanism for an extracorporeal blood tubing system for an extracorporeal blood treatment machine, preferably a dialysis machine, for triggering an emergency shut-off of the extracorporeal blood tubing system of the extracorporeal blood treatment machine in the event of needle dislocation (in particular VDN). The safety device comprises a shut-off mechanism (e.g., a tube clamp or a shut-off valve) which is suitable for (configured to) reduce or shut off the blood flow through a tubing of the extracorporeal blood tubing system of / for the associated blood treatment machine. Furthermore, the safety device comprises a (purely mechanically operating) actuating / triggering device (also referred to as a needle dislocation detection device), which is suitable for (configured to) actuate / trigger the blocking mechanism (automatically / spontaneously) when the venous patient access / venous patient connection piece of the extracorporeal blood tubing system, preferably the access cannula, and the arterial patient access / arterial patient connection piece of the extracorporeal blood tubing system, preferably the access cannula, the venous patient access / venous patient connection piece and the arterial patient access / arterial patient connection piece have a predetermined starting relative position relative to one another or are configured such that they move or are moved out of the predetermined starting relative position (by a predetermined or predeterminable amount).

[0016] Therefore, the operating device / triggering device of the safety device according to the present invention basically performs two functions, namely, detecting (responding to) changes in the originally set / current relative position between the two patient accesses of the extracorporeal blood system, and triggering at least one of the shut-off mechanisms when a limited / predeterminable change amount is reached / exceeded.

[0017] The safety device according to the invention can be used for any extracorporeal blood treatment, in particular dialysis treatment, such as hemodialysis, hemofiltration and hemodiafiltration, in which at least two patient accesses / patient connections, preferably access cannulas, are required.

[0018] The advantage of this novel safety device over known systems is that it is no longer necessary to detect a pressure loss / pressure change in the extracorporeal blood tubing system, which only indirectly indicates needle dislocation, but rather a change in the position or relative position of the two (venous and arterial) patient connections of the extracorporeal blood tubing system is detected directly, thereby enabling a direct, rapid and reliable emergency shut-off of the extracorporeal blood tubing system.

[0019] Basically, the safety device according to the invention is divided into two variants. The first of which is

[0020] - a mechanical engagement of the two patient accesses, by which the shut-off mechanism can be triggered, and another

[0021] - Monitoring of the relative position of the two patient accesses in the form of sensors and electronic control of the shut-off mechanism.

[0022] Each of these variations can be implemented or improved in different ways. These variations and some embodiments will be described in more detail below.

[0023] The present invention utilizes the technical necessity of placing several, in particular two, patient accesses in an extracorporeal blood treatment in order to connect the extracorporeal blood treatment machine (the extracorporeal blood tubing system) to the patient's blood circulation system or blood vessels, wherein the patient accesses are preferably adhesively fixed to a patient surface, such as the skin, and are thus fixed in their position relative to the patient and to each other, i.e., in their starting relative position. It follows that, in the event of needle dislocation in one of the patient accesses, the corresponding patient access or even both patient accesses moves, thus causing a displacement of the two patient accesses relative to each other, which displacement is recognizable / detectable. Accordingly, according to the present invention, the shut-off mechanism is triggered / operated depending on the relative position.

[0024] Furthermore, the detection device according to the invention triggers the pressure monitoring system, which is installed in a standard manner in the extracorporeal blood treatment machine (extracorporeal blood tubing system), thereby actuating the machine's own shut-off mechanism, and / or the safety device according to the invention has its own shut-off mechanism (in addition to the machine's own shut-off mechanism). The machine's own or the safety device's own shut-off mechanism blocks the blood flow through the corresponding line on the venous side of the extracorporeal blood tubing system, i.e., for example, downstream of the dialysis filter of the dialysis machine, in particular at the venous patient access, resulting in an increased blood pressure downstream of the location where the blood flow is blocked. The machine's own or the safety device's own shut-off mechanism blocks the blood flow through the corresponding line on the arterial side of the extracorporeal blood tubing system, i.e., for example, upstream of the dialysis filter of the dialysis machine, in particular at the arterial patient access, resulting in a decreased blood pressure downstream of the location where the blood flow is blocked. In any case, the blocking prevents the blood pump of the extracorporeal blood treatment machine from pumping blood from the patient's blood vessels into the surroundings.

[0025] The pressure changes described above occur quickly and are large enough to be reliably detected by the standardized pressure monitoring system in the treatment system, in particular the dialysis machine. This allows a response from the blood treatment machine, i.e., an alarm can be directly output and, if necessary, the blood pump can be shut down / stopped. It is particularly advantageous that the alarm can be manually turned off, but will immediately sound again due to a continued cutoff or reduction in blood flow. In principle, the shutoff mechanism of the safety device can be located anywhere in the extracorporeal blood tubing system and is not limited to the venous or arterial access.

[0026] The shut-off mechanism of the safety device may consist of one or more spatially separate components (e.g., valves, tube clamps, etc.). Furthermore, the shut-off mechanism may be adapted to specifically shut off or reduce the blood flow through the extracorporeal blood tubing system at a predetermined location, or the shut-off mechanism may be adapted to randomly shut off or reduce the blood flow at one of a plurality of predetermined locations.

[0027] According to a preferred aspect of the invention, the initial relative position of the venous patient access / venous patient connection element and the arterial patient access / arterial patient connection element is mechanically set or fixed by the detection device, in particular the operating device / triggering device, or is settable or fixable by the detection device. In other words, according to this aspect of the invention, the venous patient access and the arterial patient access are mechanically joined together in their initial relative position during the extracorporeal blood treatment (e.g., by forming a connecting rod or an articulation mechanism of the detection device). This corresponds to the first basic variant of the detection device according to the invention described above.

[0028] In this case, let's take an extracorporeal blood treatment, preferably double-needle dialysis, with a double-needle patient connector as an example, where the two patient accesses are inserted, for example, into an arterial and venous vessel of a patient. Thus, the two connectors / needles / cannulas are arranged adjacent to one another and along the vessel, broadly speaking, in a linear or parallel manner across the respective sections. Accordingly, it can be assumed that the patient accesses are approximately linear or parallel to one another in their initial relative positions. Thus, for example, the formation of a mechanical joint can be facilitated or at least simplified by a connecting rod / connecting link.

[0029] Advantageously, the detection device according to this aspect of the invention utilizes very simple components that can be manufactured inexpensively, for example, by injection molding. The simplicity of the detection device facilitates its operation and reduces the likelihood of incorrect operation by medical personnel. Furthermore, due to the mechanical engagement, the two patient accesses provide mutual strain relief, thereby preventing the patient accesses from slipping out under slight tension or impact, which would otherwise cause needle dislocation.

[0030] According to another preferred aspect of the present invention, the detection device or operating / triggering device comprises a connection portion, preferably in the form of a stick, and at least one operating / triggering portion, preferably in the form of a plug. The operating / triggering portion engages or is engageable with the blocking mechanism of the safety device, preferably attached to the venous patient access / venous patient connection piece and / or preferably attached to the arterial patient access / arterial patient connection piece. Furthermore, the operating / triggering portion is adapted to operate / trigger the blocking mechanism.

[0031] The preferred attachment of the shut-off mechanism to the venous and / or arterial patient access is understood to mean that the shut-off mechanism or a part of the shut-off mechanism is preferably arranged in the immediate vicinity of the respective patient access or is directly connected next to the patient access to the (blood) line connected to the respective patient access or is provided as a connector between the patient access and the line.

[0032] In principle, the mechanical connection of the detection device can have any suitable shape, such as a curved or plate-shaped connection. Similarly, the operating part / trigger part of the safety device can also have any shape that is suitable for operating or triggering the shut-off mechanism of the safety device. Preferably, at least one of the operating part / trigger part is designed to be plug-shaped (as already indicated above) and is suitable for being inserted into an insertion hole or eyelet of the shut-off mechanism in order to operate the shut-off mechanism or to unlock the blood flow through the corresponding pipeline. The length of the plug is designed to be dimensioned so that, on the one hand, the plug is long enough so that it can be safely inserted into the shut-off mechanism and cannot easily fall out, and on the other hand, the plug is short enough so that it falls out of the shut-off mechanism at one of the patient access points in the event of needle dislocation, and this occurs before the pulling force transmitted through the connection part causes the other patient access point to also slip out of the patient's blood vessel.

[0033] The connection part can preferably be slightly elastically deformable. In this way, slight deviations in the position of the patient access ports relative to one another can be compensated. However, the elasticity should not be too great, otherwise, in the event of needle dislocation, only the connection part would deform, while the engagement between the blocking mechanism and the operating / triggering device would not be disengaged / released.

[0034] According to another preferred aspect of the present invention, when the operating / triggering part, which is preferably in the form of a plug, is engaged with the shut-off mechanism, the shut-off mechanism, for example in the form of a hose clamp preloaded in the closing direction by a spring (shown only schematically in the figures), is held in the open position, and when the operating / triggering part is separated from the shut-off mechanism, the shut-off mechanism switches to the closed position. This ensures that patient blood can only flow through the extracorporeal blood tubing system when the operating / triggering device is connected to the shut-off mechanism. Therefore, if the operating / triggering device is not attached to the shut-off device, or in other words, if the shut-off device is not activated, the extracorporeal blood treatment cannot be started.

[0035] According to another preferred aspect of the present invention, at least one operating part / triggering part of the operating / triggering device is movable and fixed along the longitudinal axis of the connecting portion of the detection device. In this case, the movability can be ensured, for example, by a track along the connecting portion, and at least one operating part / triggering part can be secured or fixed in position along the connecting portion, for example, by a clamp or bolt. This has the advantage that the distance between the operating parts / triggering parts is infinitely adjustable.

[0036] Alternatively or additionally, a plurality of operating / triggering parts are preferably arranged along the connecting portion, preferably at equal distances from one another. If the connecting portion is configured as a stick and the operating / triggering part is configured as a plug, the operating / triggering device has a comb-like shape. This makes manufacturing very cheap, and unlike the above-described embodiments with slidable operating / triggering parts, no additional handle is required to secure them and to enable the shut-off device to function. Consequently, the possibility of incorrect operation is minimized.

[0037] According to another preferred aspect of the present invention, the shutoff mechanism comprises a plurality of separate partial shutoff mechanisms that can be manipulated / activated separately from one another. In this case, the arterial partial shutoff mechanism is attached to the arterial patient access / arterial patient connection piece and is preferably manufactured integrally therewith. Furthermore, the venous partial shutoff mechanism is attached to the venous patient access / venous patient connection piece and is preferably manufactured integrally therewith.

[0038] In other words, each of the two partial cut-off mechanisms can be adapted (configured) to cut off or reduce the blood flow through the corresponding pipeline. It is not certain which of the two partial cut-off mechanisms will trigger the cut-off or reduction of the blood flow. This only depends on which of the two partial cut-off mechanisms the operating device will fall off first and thereby trigger the cut-off through the corresponding partial cut-off mechanism. In this case, the operating device / trigger device is a detachable component that can be engaged with the two partial cut-off mechanisms in the same way. In addition, the two patient accesses are basically configured as identical components, and each patient access is preferably formed integrally with one of the partial cut-off mechanisms. This increases the number of pieces to be produced, thereby reducing production costs.

[0039] According to another preferred aspect of the present invention, the operating device / triggering device (detection device) forms a first operating device / triggering device, which is suitable for (configured to) operate / trigger the venous part shut-off mechanism. To this end, the first operating device / triggering device is mechanically engaged or engageable with the venous part shut-off mechanism and is hingedly connected or fixedly connected to the arterial patient access / arterial patient connection or the arterial part shut-off mechanism, preferably formed in one piece with it. In addition, the operating device / triggering device (detection device) according to the present invention forms a second operating device / triggering device, which is suitable for (configured to) operate / trigger the arterial part shut-off mechanism. For this purpose, the second operating device / triggering device is mechanically engaged or engageable with the arterial part shut-off mechanism and is hingedly connected or fixedly connected to the venous patient access / venous patient connection or the venous part shut-off mechanism, preferably formed in one piece with it. That is, in this preferred case, the two rods or connecting rods are arranged parallel to each other and trigger one of the two shut-off mechanisms respectively.

[0040] During needle dislocation, for example, on the venous side of the extracorporeal blood system, the venous patient access, along with the venous partial shut-off mechanism, moves relative to the arterial patient access and the arterial partial shut-off mechanism attached thereto. Thus, for example, the first actuator / trigger device detaches from the venous partial shut-off mechanism, thereby triggering / operating the venous partial shut-off mechanism and shutting off blood flow through the tubing associated with the venous partial shut-off mechanism. Simultaneously, if necessary, the second actuator / trigger device also detaches from the arterial partial shut-off mechanism, thereby potentially triggering / operating the arterial partial shut-off mechanism and shutting off blood flow through the tubing associated with the arterial partial shut-off mechanism, and vice versa.

[0041] It should be noted that it is sufficient to trigger only one partial blocking mechanism. In this respect, it is generally sufficient to provide a corresponding blocking mechanism on one of the two patient connection pieces / patient accesses, while the actuating device / triggering device is only articulated / mounted on the other patient connection piece / patient access (without a blocking mechanism).

[0042] The first operating device / trigger is attached to, for example, the arterial partial shutoff mechanism or the arterial patient access or is fixedly connected thereto. Similarly, the second operating device / trigger is attached to, for example, the venous partial shutoff mechanism or the venous patient access or is fixedly connected thereto. Each patient access or the partial shutoff mechanism disposed thereon may be provided with, for example, an eyelet or slot, into which one of the operating devices / trigger is hung or can be hung, or clipped or can be clipped. This is preferably configured in the form of a comb or a toothed rod. In this case, the operation of engaging the operating device / trigger with the corresponding partial shutoff mechanism is simplified. It is only necessary to ensure that the distance between the two patient connection parts is substantially fixed by the rigidity of the connection. Alternatively, the operating part / trigger can be integrally connected or injection molded with the corresponding patient access and / or the partial shutoff mechanism attached thereto. In this case, the shutoff device can be manufactured more easily and more cheaply. Thus, the two partial shutoff mechanisms can be the same component or assembly as the associated patient access, thereby increasing the number of parts to be manufactured. Furthermore, in this case the shut-off device has no separate / detachable parts that could be lost or dropped.

[0043] In principle, the system can be modified so that only one actuating / triggering device (as described above) is provided, which is connected to one of the patient accesses as described above and actuates the blocking mechanism provided only at the other patient access.

[0044] According to another preferred aspect of the present invention, the operating / triggering device is adapted (configured) to monitor the initial relative positions of the venous patient access / venous patient connection and the arterial patient access / arterial patient connection relative to each other in a sensor-like or optical manner. Furthermore, the operating / triggering device is adapted (configured) to control the shut-off mechanism electrically, preferably wirelessly.

[0045] This corresponds to the above-described second basic variant of the shut-off device according to the invention.

[0046] As in the first variant, the shut-off device according to the second variant can be designed such that the shut-off mechanism shuts off or reduces the blood flow through the corresponding line as long as the shut-off device or the operating / triggering device is not activated, for example by pressing a button or a switch. This ensures that extracorporeal blood treatment cannot be started if the shut-off device is not ready for use.

[0047] Advantageously, according to this aspect of the invention, the shutoff mechanism can be attached to any suitable location on the extracorporeal blood tubing system, for example, directly upstream of the blood pump of the extracorporeal blood treatment machine. This allows for greater design flexibility and makes the access cannula more lightweight. Similarly, compared to variants with mechanical engagement, the shutoff mechanism is no longer prevented from becoming untriggerable due to a jamming of the operating / triggering mechanism.

[0048] The data connection can be provided, for example, by radio, Bluetooth or cable. The data processing module can be provided as a separate device, installed in the extracorporeal blood treatment machine itself, or arranged at any suitable location. For the position monitoring, markers or sensors can be attached to the patient access. Furthermore, for the position monitoring, in principle, any suitable position sensor and / or distance sensor, such as an infrared sensor or an inductive sensor, can be used. Other examples include GPS monitoring, ultrasonic or laser sensors, or position detection by a camera and associated image processing.

[0049] In principle, the safety device according to this aspect of the invention can be used with any arrangement of patient accesses. For example, in the case of patient accesses attached to different patient arms, additional reference points / markers may be provided on the patient's skin next to the corresponding accesses to prevent arm movements from triggering the shutoff. This shows that the shutoff device according to this aspect of the invention is also suitable for other applications where only one patient access is provided. For example, in infusions, the shutoff device according to the invention can prevent leakage of medication, etc., in the event of needle dislocation.

[0050] According to another preferred aspect of the present invention, the shutoff mechanism has a pipeline clamping element that is resettable by a spring element, the pipeline clamping element being used to clamp the pipeline of the extracorporeal blood treatment machine, or has a shutoff valve.

[0051] The shut-off valve can be, for example, a solenoid-driven, electric-motor-driven or mechanically-driven valve. It can be mechanically controllable, for example by creating an electrical contact in the shut-off mechanism via an actuating element according to one of the aforementioned aspects of the invention, or it can be electrically controllable. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The present invention will be described below with reference to preferred embodiments, wherein features of the various embodiments may be interchanged and / or combined. It should be understood that the details of the preferred embodiments described are not intended to limit the invention itself, and that various changes, modifications, and / or equivalents will be apparent to those skilled in the art, all of which are within the scope of protection of the present invention. In addition, in the following description of the preferred embodiments, the same reference numerals are used for features that correspond to each other, and the features may be described only once, but are applicable to each of the embodiments described.

[0053] Figure 1 shows a safety device according to the invention according to a first embodiment during extracorporeal blood treatment;

[0054] Figure 2 shows a side view and a top view of a connecting element of the safety device according to the first embodiment;

[0055] Figure 3 shows a detailed view of a patient access / patient connection piece with a safety device according to the invention according to said first embodiment;

[0056] Figure 4 Various arrangements or starting relative positions of the patient access / patient connection components of the safety device according to the first embodiment are shown;

[0057] Figure 5 shows a safety device according to the invention according to a second embodiment of the invention;

[0058] Figure 6 A schematic diagram shows a safety device according to the invention according to a third embodiment of the invention during extracorporeal blood treatment.

[0059] Reference Signs List

[0060] D Dialysis Machine

[0061] 1 Patient's arm

[0062] 2 Patient's vein

[0063] 3 Patient arteries

[0064] 4 shunts

[0065] 5 Blood flow direction

[0066] 6 Arterial patient access / arterial patient connector (arterial access cannula)

[0067] 7 Arterial (blood) lines

[0068] 8 Cut-off Agency

[0069] 8a Arterial partial cut-off mechanism

[0070] 8b Venous cut-off mechanism

[0071] 9 Venous (blood) lines

[0072] 10 Venous patient access / venous patient connector (venous access cannula)

[0073] 11. Control device / trigger device / detection device

[0074] 11a First operating device / triggering device / detection device

[0075] 11b Second operating device / triggering device / detection device

[0076] 12. Connection

[0077] 13. Control part / trigger part (plug)

[0078] 14. Control unit / trigger unit (data processing module)

[0079] 15. Connection (data connection) DETAILED DESCRIPTION

[0080] Figure 1 A patient's arm 1 is shown schematically during extracorporeal blood treatment, using double-needle dialysis as an example, which requires the arrangement described below. A patient vein 2 and a patient artery 3 are connected via a shunt 4. A broad arrow marks the direction of blood flow 5 through the patient vein 2. The shunt 4 ensures that an extracorporeal blood treatment machine D can be connected to a large-capacity patient vessel, particularly the patient vein 2, at a sufficiently high flow rate. In the following figures and embodiments, the extracorporeal blood treatment machine D is not shown separately, but it should be understood that it is provided in each of the described embodiments.

[0081] Downstream of the flow diverter 4 and in the blood flow direction 5, an arterial access cannula 6 serving as an arterial patient access / arterial patient connection is inserted into the patient's blood vessel 2. The access cannula 6 is fluidically connected to an arterial (blood) line 7 of an extracorporeal blood line system 7, 9 of an extracorporeal blood treatment machine (not shown), so that blood is transported from the patient's blood vessel 2 to the extracorporeal blood treatment machine via the arterial access cannula 6.

[0082] At the arterial line 7, an arterial partial shutoff mechanism 8a, which is a portion of the (entire) shutoff mechanism 8, is arranged in close proximity to (or directly on) the arterial access cannula 6, particularly at the connection between the arterial line 7 and the arterial access cannula 6, where the two are fluidically connected to each other. The arterial partial shutoff mechanism 8a is adapted to shut off or reduce blood flow through the arterial line 7 when manipulated or triggered.

[0083] The blood drawn from the patient's blood vessel 2 flows through the extracorporeal blood treatment machine or filter (not shown further) and is returned to the patient's blood vessel 2 via the venous (blood) line 9 of the extracorporeal blood tubing system and via a venous access cannula 10 fluidically connected to the venous line 9. Simultaneously, the venous access cannula 10 is inserted into the patient's blood vessel 2 on the side downstream of the arterial access cannula 6 in the direction of blood flow 5 and serves as a venous patient access / patient connection.

[0084] A venous partial shut-off mechanism 8b, which is part of the (entire) shut-off mechanism 8, is arranged on the venous line 9 in close proximity to (or directly on) the venous access cannula 10, and in particular at the connection between the venous line 9 and the venous access cannula 10, where the two are fluidically connected. The venous partial shut-off mechanism 8b is adapted to interrupt or reduce blood flow through the venous line 9 when actuated or triggered. The arterial partial shut-off mechanism 8a and the venous partial shut-off mechanism 8b together constitute the shut-off mechanism 8.

[0085] The two access cannulas 6, 10 are arranged in a predetermined starting relative position relative to one another, wherein the distance between the two access cannulas 6, 10 does not exceed a predetermined maximum distance, as will be described in more detail below. The arterial access cannula 6 and the venous access cannula 10 are each preferably adhesively fixed to a patient surface, in particular to the patient's skin, in their starting relative position.

[0086] exist Figure 1 In the state shown, in which the two access cannulas (connecting pieces) 6, 10 have a predetermined starting relative position relative to one another, the arterial access cannula 6 or the arterial line 7 is connected by

[0087] - the arterial portion cut-off mechanism 8a,

[0088] - an operating device / triggering device (detection device) 11 in the form of a comb, a grid or a toothed bar, and

[0089] - The venous partial cut-off mechanism 8b

[0090] Mechanically engaged with the venous access cannula 10 or the venous line 9 .

[0091] The operating / triggering device 11 interacts with the two partial shut-off mechanisms 8a, 8b such that, on the one hand, when the partial shut-off mechanisms 8a, 8b are engaged with the operating / triggering device 11, the partial shut-off mechanisms 8a, 8b are in (or remain in) an open position, thereby releasing blood flow through the respective associated lines 7, 9, and, on the other hand, when the partial shut-off mechanisms 8a, 8b are not engaged with the operating / triggering device 11, the partial shut-off mechanisms 8a, 8b are in (or remain in) a blocked position, in which the blood flow through the associated lines 7, 9 is blocked or reduced. In other words, when, for example, the engagement between the arterial partial shut-off mechanism 8a and the operating / triggering device 11 is released or released, the arterial partial shut-off mechanism 8a switches from the open position to the blocked position, thereby interrupting or reducing blood flow through the arterial line 7. The same applies to the operating principle of the venous partial shut-off mechanism 8b.

[0092] At this point it should be clearly pointed out that it is sufficient to provide only one partial shut-off mechanism for the function of the safety device, wherein in this case the operating / triggering device 11 is engaged with the one partial shut-off mechanism at one end and is, for example, directly mounted to the other access cannula at the other end. It is also possible to provide two operating / triggering devices, for example in the form of rods as shown, each of which actuates one of the two partial shut-off mechanisms (independent of each other).

[0093] The following will refer to Figure 2 and 3 The operating device / triggering device 11 and its operating principle are described in more detail.

[0094] Figure 2The operating / triggering device 11 according to a first embodiment is shown, designed as a connecting rail or rod with comb-like or axially spaced connection points. In this particular case, the operating / triggering device 11 comprises a substantially stick-shaped connecting portion (straight stick) 12, which is rigid or elastically deformable / stretchable only to a limited extent in its longitudinal direction, so that its ends are always substantially at the same distance from one another. The length of the connecting portion 12 defines the maximum distance that the two partial shut-off means 8a, 8b, and therefore the two access cannulas 6, 10, can have relative to one another when they are in the predetermined starting relative position. Along the connecting portion 12, equidistantly spaced plugs / protrusions 13, preferably with a circular cross-section, are provided as operating / triggering portions. These plugs / protrusions 13 are located in a plane and are designed as a single piece with the connecting portion 12, preferably as an injection-molded part.

[0095] Figure 3 The arterial access cannula 6 is shown by way of example, with an arterial line 7 connected thereto and a portion of the safety device according to the present invention according to the first embodiment, specifically, the arterial partial blocking mechanism 8a, which engages with the operating / triggering device 11. This engagement is ensured by inserting a plug / protrusion 13 into an insertion hole provided in the arterial partial blocking mechanism 8a, thereby moving the arterial partial blocking mechanism 8a into / maintaining the open position. For example, the plug 13 presses against a restoring force or spring force against a rod or pin extending into the insertion hole. The rod or pin is configured to clamp the line 7 or significantly reduce blood flow through the line 7 when the plug 13 is not pressing against the rod or plug on one side.

[0096] Figure 4 Various exemplary arrangements or starting relative positions of the two access cannulas 6 , 10 with respect to each other of the shut-off device according to the first embodiment are shown.

[0097] In the first arrangement (top), the two access cannulas 6, 10 are oriented substantially parallel to one another; in the second arrangement (center), they are oriented substantially in opposite directions or opposite one another; and in the third arrangement (bottom), the distance between the two access cannulas 6, 10 is significantly reduced, and the operating / triggering device 11 protrudes noticeably from one of the partial shutoff mechanisms 8a, 8b. This flexible arrangement is possible due to the circular cross-section of the plugs 13 and the number of plugs 13 distributed along the connecting portion 12. Thus, the operating / triggering device 11 can be rotated relative to each partial shutoff mechanism 8a, 8b about the longitudinal axis of the plug 13 inserted into the corresponding partial shutoff mechanism 8a, 8b. Furthermore, any two plugs 13 of the operating / triggering device 11 can be inserted into the partial shutoff mechanisms 8a, 8b, thereby allowing the operating / triggering device 11 to adapt the distance between the partial shutoff mechanisms 8a, 8b and, therefore, their predetermined starting relative positions.

[0098] Because the stoppers are positioned at a fixed distance from one another, the distance between the partial blocking mechanisms 8a, 8b, and therefore the access cannula on which the partial blocking mechanisms are mounted / provided, remains fixed during use during an extracorporeal blood treatment procedure. If, for example, a venous needle is dislodged due to an impact on the venous line 9, the venous access cannula 10 may accordingly at least partially slip out of the patient's vein 2, thereby also displacing the associated venous partial blocking mechanism 8b. In other words, the two access cannulas 6, 10 and the corresponding partial blocking mechanisms 8a, 8b may move relative to one another out of their predetermined / predeterminable starting position by the operating / triggering device 11, and their relative distance may change. However, since the connecting portion 12 of the operating / triggering device 11 is substantially rigid or elastically deformable only to a limited extent, the plug 13 inserted into the insertion hole of the partial shutoff mechanism 8a, 8b may slide out of at least one of the partial shutoff mechanisms 8a, 8b due to reaching / exceeding a maximum permissible position change (determined, in particular, by the elasticity of the connecting portion 12 and the clearance between the plug and the insertion hole), and thus the shutoff mechanism 8 is actuated by operating the corresponding partial shutoff mechanism 8a, 8b and switching it to the shutoff position. The length of the plug is preferably designed so that the plug safely slides out of the insertion hole of one of the partial shutoff mechanisms 8a, 8b before the impact transmitted from the venous access cannula 10 to the arterial access cannula 6 via the operating / triggering device 11 causes the arterial needle to be dislocated.

[0099] In this respect, the operating device / triggering device 11 can also be referred to as a detection device, since it triggers at least one partial shut-off mechanism in response to a change in the relative position of the two access cannulas, thereby urgently locking the entire extracorporeal blood tubing system.

[0100] Figure 5 A safety device according to the present invention according to a second embodiment is schematically shown. The safety device comprises a first operating / triggering device 11a, which is fixedly connected or injection-molded with the arterial cutoff mechanism 8a (schematically represented by a black block) and engages with the venous cutoff mechanism 8b for operation thereof when necessary. Furthermore, a corresponding second operating / triggering device 11b is provided, which is fixedly connected or injection-molded with the venous cutoff mechanism 8b and engages with the arterial cutoff mechanism 8a for operation thereof when necessary. Thus, the patient access and the parts of the safety device arranged or fixed thereto can be designed as a single component.

[0101] Figure 6 A safety device according to the invention according to a third embodiment of the invention is schematically shown during an extracorporeal blood treatment. This embodiment differs from the first embodiment primarily in that the two partial shut-off mechanisms 8a, 8b are not mechanically coupled via the operating / triggering device 11, but rather the shut-off mechanism 8 or the partial shut-off mechanisms 8a, 8b are electrically controllable or triggerable. The operating / triggering device 11 according to the third embodiment comprises a data processing module 14 as an operating / triggering section, wherein during the extracorporeal blood treatment, a data connection 15 is established as a connection between the data processing module 14 and the partial shut-off mechanisms 8a, 8b. Markers or sensors, for example, are attached to the partial shut-off mechanisms 8a, 8b, with the aid of which the data processing module 14 monitors the relative position of the partial shut-off mechanisms 8a, 8b and can detect movement out of a predetermined starting relative position during the extracorporeal blood treatment. When such a movement is detected, the data processing module 14 is adapted to control the shut-off mechanism 8 or the partial shut-off mechanisms 8 a , 8 b via the data connection 15 in such a way that they switch from the open position to the shut-off position.

Claims

1. A safety device for an extracorporeal blood tubing system of an extracorporeal blood treatment machine, the safety device being configured to trigger an emergency shutoff of the extracorporeal blood tubing system in the event of needle dislocation. It is characterized by: include a shut-off mechanism (8) adapted to reduce or shut off the blood flow through the tubes (7, 9) of the extracorporeal blood treatment machine, and an operating / triggering device (11) adapted to detect a change in a predetermined starting relative position of a venous patient access / venous patient connection piece (10) and an arterial patient access / arterial patient connection piece (6) of the extracorporeal blood tubing system relative to one another, the venous patient access / venous patient connection piece (10) and the arterial patient access / arterial patient connection piece (6) having or being arranged relative to one another in the predetermined starting relative position, and to operate / trigger the shut-off mechanism (8) when the venous patient access / venous patient connection piece (10) and the arterial patient access / arterial patient connection piece (6) move or are moved out of the predetermined starting relative position by a predetermined or predeterminable amount of change, The operating device / triggering device (11) comprises a connecting portion (12) and at least one operating portion / triggering portion (13), wherein the operating portion / triggering portion (13) is engaged with or can be engaged with the shut-off mechanism (8), the shut-off mechanism (8) being attached to the venous patient access / venous patient connection (10) and / or the arterial patient access / arterial patient connection (6), and the operating portion / triggering portion (13) is suitable for operating / triggering the shut-off mechanism (8).

2. The safety device according to claim 1, wherein: When the operating part / trigger part (13) is engaged with the shut-off mechanism (8), the shut-off mechanism (8) is in the open position, and when the operating part / trigger part (13) is separated from the shut-off mechanism (8), the shut-off mechanism (8) is in the shut-off position.

3. The safety device according to claim 1 or 2, wherein: The at least one operating part / triggering part (13) of the operating device / triggering device (11) is movable and fixable along the longitudinal axis of the connecting part (12), or a plurality of operating parts / triggering parts (13) are arranged along the connecting part (12).

4. The safety device according to claim 1, wherein: The shut-off mechanism (8) has a plurality of separate shut-off mechanism parts (8a, 8b), which can be actuated / triggered separately from one another, and An arterial portion cut-off mechanism (8a) is attached to the arterial patient access / arterial patient connection (6), and a venous portion cut-off mechanism (8b) is attached to the venous patient access / venous patient connection (10).

5. The safety device according to claim 4, wherein The operating device / triggering device (11) has a first operating device / triggering device (11a) and a second operating device / triggering device (11b). The first operating device / triggering device (11a) is engaged or engageable with the venous part shut-off mechanism (8b), the first operating device / triggering device (11a) is further adapted to operate / trigger the venous part shut-off mechanism (8b), and the first operating device / triggering device (11a) is connected to the arterial patient access / arterial patient connection (6) and / or the arterial part shut-off mechanism (8a), and The second operating device / triggering device (11b) is engaged with or can be engaged with the arterial part shut-off mechanism (8a), the second operating device / triggering device (11b) is also suitable for operating / triggering the arterial part shut-off mechanism (8a), and the second operating device / triggering device (11b) is connected to the venous patient access / venous patient connection (10) and / or the venous part shut-off mechanism (8a).

6. The safety device according to claim 1, wherein: The operating device / triggering device (11) is suitable for monitoring the initial relative position of the venous patient access / venous patient connection (10) and the arterial patient access / arterial patient connection (6) relative to each other in the form of a sensor and / or for electrically controlling the shut-off mechanism (8).

7. The safety device according to claim 1, wherein: The shut-off mechanism (8) has a pipeline clamping element which can be reset by a spring element and is used for clamping the pipeline (7, 9) of the extracorporeal blood treatment machine, or has a non-return valve.

8. The safety device according to claim 1, wherein: The venous patient access / venous patient connection piece (10) and the arterial patient access / arterial patient connection piece (6) of the extracorporeal blood tubing system are configured as access cannulas.

9. The safety device according to claim 1, wherein: The connecting portion (12) is in the shape of a stick.

10. The safety device according to claim 1, wherein: The operating part / trigger part is plug-shaped.

11. The safety device according to claim 4, wherein: The arterial part cut-off mechanism (8a) is integrally formed with the arterial patient access / arterial patient connection (6), and / or the venous part cut-off mechanism (8b) is integrally formed with the venous patient access / venous patient connection (10).

12. The safety device according to claim 5, wherein: The first operating device / triggering device (11a) is configured as a whole with the arterial patient access / arterial patient connection (6) and / or the arterial part shut-off mechanism (8a), and / or the second operating device / triggering device (11b) is configured as a whole with the venous patient access / venous patient connection (10) and / or the venous part shut-off mechanism (8a).

13. The safety device according to claim 6, wherein: The operating device / triggering device (11) controls the blocking mechanism (8) wirelessly.

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