Testing devices for an invasive device entry indicator

Abstract

A device tester is described for use with an invasive device entry indicator comprising a pressure sensor configured to be in fluid communication with a needle bore of the needle in use, at least one selectively activated indicator, wherein the invasive device entry indicator is configured to activate the indicator while pressure acting on the pressure sensor is above a minimum threshold. The device tester comprises a hollow deformable portion, and a fluid port configured to fluidly connect an interior of the hollow deformable portion to the pressure sensor in use. The hollow deformable portion comprises at least one air bleed aperture between the interior of the hollow deformable portion and external atmosphere.

Description

TESTING DEVICES FOR AN INVASIVE DEVICE ENTRY INDICATORSTATEMENT OF CORRESPONDING APPLICATIONS

[0001] This application is based on the Provisional specification filed in relation to Australian Patent Application Number 2024904269, the entire contents of which are incorporated herein by reference.TECHNICAL FIELD

[0002] The present technology relates to testing devices for an invasive device entry indicator configured to indicate when an invasive device such as a catheter needle enters a body cavity, duct, or vessel of a human or non-human animal vessel - more particularly a blood vessel (e.g., a vein or artery).BACKGROUND

[0003] Peripheral intravenous catheters are the most commonly used invasive devices for the purpose of obtaining blood samples, or to administer drugs, fluids and blood products. Both intravenous cannulation and arterial cannulation involve puncturing a vein or an artery with an intravascular needle, then sliding a plastic tube (i.e., catheter) over the needle and into the said vein or artery. The catheter then remains inside the vein or artery, whilst the needle is discarded.

[0004] It is not uncommon for several punctures to be required in order to achieve successful catheterization. If the tip of the needle leaves the inside of the vein or artery during cannulation, for example due to patient movement or a double puncture of a vein, before the catheter is advanced, it is then impossible to successfully advance the catheter into the vein.

[0005] These successive attempts can produce pain and delay the start of diagnostic treatments or tests. Additionally, repeated punctures can degrade vascular walls which complicate subsequent attempts. This may produce serious complications associated with vascular access, such as bruising, catheter-associated infection, extravasation, haemorrhages, phlebitis, and sepsis.

[0006] Devices for indicating the position of a needle have been proposed. However, such devices are not considered sufficiently reliable so as to be clinically useful, and / or are cost prohibitive due to complexity of components and construction, and / or are poorly suited to use in high pressure scenarios such as when providing emergency medical treatment at a point of wounding in a combat or training environment.

[0007] PCT Application No. PCT / NZ2024 / 050031 describes an invasive device entry indicator configured to output an indication of whether a needle is inserted into a vein based on pressure through the needle bore.

[0008] For medical equipment, it is generally desirable for users to be able to test a device prior to use.Ideally, the means for testing should ideally be capable of sterilisation with the device. Further, the means for testing should remain inactive under changing environmental conditions (for example, changes in air pressure due to variation in altitude during air transport).

[0009] It is an object of the present disclosure to address at least one of the foregoing problems or at least to provide the public with a useful choice.

[0010] Further aspects and advantages of the present disclosure will become apparent from the ensuing description which is given by way of example only.SUMMARY

[0011] According to an aspect of the present technology there is provided a device to indicate entry of a needle into a body cavity, duct, or vessel of a human or non-human animal, the device comprising: a pressure sensor configured to be in fluid communication with a needle bore of the needle in use; and at least one selectively activated indicator, wherein the device is configured to activate the indicator while pressure acting on the pressure sensor is above a minimum threshold.

[0012] In examples the device may be configured to deactivate the indicator while the pressure acting on the pressure sensor is below minimum threshold.

[0013] Examples of the device of the present technology may be configured for use in various body cavities, ducts, or vessels of a human or non-human animal. While examples of the present technology may be configured for use in indicating entry of a needle into a blood vessel of a human (e.g., a vein or artery), it should be appreciated that principles of those examples may be adapted for use in other body cavities, ducts, or vessels.

[0014] According to another aspect of the present technology there is provided a device to indicate entry of a needle into a body cavity, duct, or vessel of a human or non-human animal, the device comprising: a pressure sensor configured to be in fluid communication with a needle bore of the needle in use; and at least one selectively activated indicator, wherein the device is configured to activate the indicator while pressure acting on the pressure sensor is about 25 cmF O and above.

[0015] In examples, the device may be configured to activate the at least one indicator while pressure acting on the pressure sensor is about 30 cmF O and above.

[0016] In examples, the device may be configured to activate the at least one indicator at all pressures from the minimum threshold through to least 100 cmHzO. In examples, the device may be configured to activate the indicator at all pressures from the minimum pressure through to at least about 250 cmF O. In examples, the device may be configured to activate the at least one indicator at all pressures from the minimum threshold through to about 500 cmHjO.

[0017] In examples, the at least one indicator may be configured to output a visual signal when activated. For example, the at least one indicator may be configured to output light when activated. In examples, the indicator may comprise a light configured to output light in the visible spectrum. In examples, the indicator may comprise a light configured to output light in the non-visible spectrum. In examples the indicator may output near-infrared or infrared light when activated.

[0018] In examples, the at least one indicator may be configured to output an audible signal when activated.

[0019] In examples, the pressure sensor may comprise at least one diaphragm that is deformable under fluid pressure from a first configuration to a second configuration, wherein in the first configuration the indicator is not activated, and in the second configuration the indicator is activated. In examples, in the second configuration the diaphragm closes a switch to activate the indicator.

[0020] In examples, the device may comprise at least one flexible printed circuit. In examples, the device may be configured such that in its second configuration the diaphragm displaces at least a movable portion of the flexible printed circuit to complete an electrical circuit and activate the indicator.

[0021] In examples, the pressure sensor may comprise a digital pressure sensor. In examples, the digital pressure sensor may be configured as a pressure switch, outputting a signal to activate the indicator when the sensed pressure is above the minimum threshold. In examples the pressure sensor may output a signal indicative of pressure to a controller, and the controller may selectively activate the indicator based on a determination of whether the pressure is above the minim threshold.

[0022] In examples the device may comprise a body containing the pressure sensor. In examples comprising at least one diaphragm, the body may comprise a first internal cavity between a first face of the diaphragm and a fluid port in fluid communication with the needle bore of the needle in use. In examples the body may comprise a second internal cavity formed in part by a second face of the diaphragm opposing the first face. In examples the body may comprise at least one air port between the second cavity and an exterior of the body. In examples the at least one air port may be provided in an end surface of the body distal from the fluid port. In examples the body comprises a plurality of air ports.

[0023] In examples the fluid port may comprise an inlet at an exterior of the body and an outlet at the first internal cavity. In examples the inlet and the outlet of the fluid port may be axially aligned with a central portion of the diaphragm.

[0024] In examples, the device may comprise at least one battery. In examples the at least one battery may be an alkaline battery. In examples the at least one battery may be a button cell. In examples the device may include a plurality of batteries. In examples the plurality of batteries may be stacked in series. In examples the plurality of batteries may be provided along a longitudinal axis between a first end of the body and a second end of the body.

[0025] According to another aspect of the present technology there is provided a device to indicate entry of a needle into a body cavity, duct, or vessel of a human or non-human animal, the device comprising: a pressure sensor configured to be in fluid communication with a needle bore of the needle in use; and at least one selectively activated indicator, wherein the at least one selectively activated indicator has at least a first indicator output and a second indicator output; wherein the device is configured to: activate the first indicator output when the pressure acting on the pressure sensor is within a first pressure range; and activate the second indicator output when the pressure acting on the pressure sensor is within a second pressure range, wherein the second pressure range is greater than the first pressure range.

[0026] In examples, the first pressure range may be indicative of central venous pressure (CVP). In examples the second pressure range may be indicative of non-CVP. In examples, the first pressure range may be from about 3 cmh O to about 40 cmHzO. in examples the second pressure range may be from about 40 cmh O and above.

[0027] In examples the device comprises a first selectively activated indicator providing the first indicator output and a second selectively activated indicator providing the second indicator output.

[0028] In examples, the pressure sensor may comprise at least two diaphragms, each diaphragm configured to be deformable under fluid pressure from a first configuration to a second configuration. In examples, the device may be configured such that the first indicator output is activated when a first diaphragm is in the second configuration, and a second diaphragm is in the first configuration. In examples, the device may be configured such that the second indicator output is activated when the first diaphragm is in the second configuration, and the second diaphragm is in the second configuration. In examples the at least two diaphragms may be arranged in stages.

[0029] In examples the device may comprise at least one flexible printed circuit portion, comprising a first contact portion configured to contact the first diaphragm when the first diaphragm is in the second configuration, and a second contact portion configured to contact the second diaphragm when the second diaphragm is in the second configuration.

[0030] In examples, the pressure sensor may comprise a digital pressure sensor. In examples, the digital pressure sensor may be configured as a pressure switch, outputting a first signal to activate the first indicator output when the sensed pressure is the within the first pressure range, and outputting a second signal to activate the second indicator output when the sensed pressure is the within the second pressure range. In examples the pressure sensor may output a signal indicative of pressure to a controller, and the controller may selectively activate the first indicator output or the second indicator output at least one indicator based on a determination of whether the pressure is within the first pressure range or the second pressure range.

[0031] In examples the at least one selectively activated indicator may be a light. In examples the first indicator output may be a first colour and the second indicator output may be a second colour different to the first colour. In examples the first colour may be green, and the second colour may be red.

[0032] According to another aspect of the present technology there is provided a device to indicate entry of a needle into a human or animal vessel or cavity comprising: a diaphragm that is deformable under fluid pressure from a first configuration to a second configuration; an electrical circuit having at least one powerable indicator; wherein when the diaphragm is in its first configuration the indicator is not powered; when the diaphragm is in its second configuration the indicator is powered, and wherein deformation of the diaphragm into its second configuration completes the electrical circuit and powers the indicator.

[0033] By providing a diaphragm that touches a surface so as to complete an electrical circuit a simply constructed and inexpensive indicating device may be created. Further, by providing a powered indicator that is more readily detectable in comparison to prior art indicators a user is able to concentrate on the task at hand (for example cannulation) rather than concentrating on monitoring whether or not an indicator is activated. Beneficially a powered indicator may operate in low light situations such as battlefields or other emergency non-hospital environments. A visual indicator such as a light (such as an LED) may be observed by a user's peripheral vision. An audio indicator such as a buzzer may be heard by a user regardless of where they are looking.

[0034] In examples the electrical circuit may comprise at least one flexible printed circuit portion, and in its second configuration the diaphragm displaces a movable part of the flexible printed circuit such that the movable part touches a surface so as to complete the electrical circuit and power the indicator.

[0035] In examples the surface may be another part of the flexible printed circuit, or a terminal of a battery.

[0036] In examples a spacer may be provided to determine a distance of travel for the movable part of the flexible printed circuit.

[0037] In examples the diaphragm may comprise a conductive material that connects the electrical circuit when the diaphragm is in its second position. In examples the diaphragm may be substantially formed of conductive elastomeric material.

[0038] In examples when the diaphragm is in its second position it touches a single contact to connect the circuit, or when the diaphragm is in its second position it touches two contacts to connect the circuit. In examples, when the diaphragm is in its second position it touches and activates a pressure-operated switch to connect the circuit.

[0039] In examples a diaphragm may be retained over a projection, wherein a face of the projection comprises an outlet for fluid to deform the diaphragm.

[0040] In examples a face of the projection may comprise a substantially central outlet for fluid to deform the diaphragm.

[0041] In examples a face of the projection comprises at least one indentation. Provision of at least one indentation may reduce the possibility of a membrane being hindered from moving by sticking to the face of the projection. For example, a face of the projection may be concave or funnel-shaped.

[0042] In examples a face of the projection may comprise at least one groove in its surface extending from the outlet, or comprises a plurality of grooves in its surface extending from the outlet.

[0043] In examples the projection may be substantially circular, and the face may be substantially circular.

[0044] In examples embodiments the diaphragm may be retained upon the projection by a ring.

[0045] In examples the diaphragm may be deformable into its second configuration under arterial pressure, but not under venous pressure.

[0046] In examples the diaphragm may be deformable into its second configuration under venous pressure and alterable into a third configuration under arterial pressure, and when the diaphragm is in its third configuration the indicator is not powered.

[0047] In examples, in its third configuration the diaphragm is ruptured.

[0048] In examples a male conduit portion configured to mate with a cannulas' female recess is one or more of: at least 5mm in length, at least 6mm in length, at least 7mm in length, and at least 8mm in length. By providing a male conduit portion that is at least 8mm in length, empty space that is formed when the conduit portion is mated with an 8mm deep female recess may be minimized.

[0049] In examples, a chamber in which the diaphragm deforms may be in fluid communication with the external atmosphere by means of at least one aperture.

[0050] In examples the diaphragm may be crimped.

[0051] According to another aspect of the present technology there is provided a device tester for an invasive device entry indicator comprising a pressure sensor configured to be in fluid communication with a needle bore of a needle in use, at least one selectively activated indicator, wherein the invasive device entry indicator is configured to activate the indicator while pressure acting on the pressure sensor is above a minimum threshold, the device tester comprising: a hollow deformable portion; and a fluid port configured to fluidly connect an interior of the hollow deformable portion to the pressure sensor in use, wherein the hollow deformable portion comprises at least one air bleed aperture between the interior of the hollow deformable portion and external atmosphere.

[0052] In examples, the hollow deformable portion comprises a first air bleed aperture in a first surface portion, and a second air bleed aperture in a second surface portion opposing the first surface portion.

[0053] In examples, the at least one air bleed aperture may be provided in a locating feature. In examples the locating feature may include a depression surrounding the air bleed aperture.

[0054] In examples, a longitudinal cross-sectional shape of the hollow deformable portion is substantially flat. In examples, the longitudinal cross-sectional shape is substantially ovaloid. In examples, the at least one air bleed aperture is located in a region proximal to a co-vertex of the hollow deformable portion.

[0055] According to another aspect of the present technology there is provided a method of testing an invasive device entry indicator comprising a pressure sensor configured to be in fluid communication with a needle bore of a needle in use, and at least one selectively activated indicator, wherein the invasive device entry indicator is configured to activate the indicator while pressure acting on the pressure sensor is above a minimum threshold, the method comprising: providing a device tester to the invasive device entry indicator, the device tester comprising: a hollow deformable portion; and a fluid port configured to fluidly connect an interior of the hollow deformable portion to the pressure sensor in use, wherein the hollow deformable portion comprises at least one air bleed aperture between the interior of the hollow deformable portion and external atmosphere; positioning a digit of a user over the at least one air bleed aperture; and deforming the hollow deformable portion to apply increased pressure to the pressure sensor of the invasive device entry indicator.

[0056] According to another aspect of the present technology there is provided a device tester for an invasive device entry indicator comprising a pressure sensor configured to be in fluid communication with a needle bore of the needle in use, at least one selectively activated indicator, wherein the invasive device entry indicator is configured to activate the indicator while pressure acting on the pressure sensor is above a minimum threshold, the device tester comprising: a hollow deformable portion; and a fluid port having a bore configured to fluidly connect an interior of the hollow deformable portion to the pressure sensor in use, wherein the bore comprises at least one recessed air bleed feature between the interior of the hollow deformable portion and external atmosphere.

[0057] According to another aspect of the present technology there is provided a device tester for an invasive device entry indicator comprising a pressure sensor configured to be in fluid communication with a needle bore of the needle in use, at least one selectively activated indicator, wherein the invasive device entry indicator is configured to activate the indicator while pressure acting on the pressure sensor is above a minimum threshold, and the invasive device entry indicator comprises at least one air-port between the pressure sensor and external atmosphere, the device tester comprising: a hollow receptacle portion having an interior configured to receive the invasive device entry indicator in use such that the at least one air-port is blocked from external atmosphere during testing; and an actuator portion configured to be pulled by a user in use to create a suction effect through the at least one air-port on the pressure sensor.

[0058] According to another aspect of the present technology there is provided a device tester for an invasive device entry indicator comprising a pressure sensor configured to be in fluid communication with a needle bore of the needle in use, at least one selectively activated indicator, wherein the invasive device entry indicator is configured to activate the indicator while pressure acting on the pressure sensor is above a minimum threshold, the device tester comprising: a shaft configured to be inserted into the invasive device entry indicator in use to mechanically apply pressure to the pressure sensor; and a stopper configured to restrict travel of the shaft into the invasive device entry indicator beyond a predetermined point.

[0059] According to another aspect of the present technology there is provided a kit of parts comprising the device of any preceding embodiment described above and the device tester of any preceding embodiment described above.

[0060] In examples, the kit of parts may comprise a sealed package containing the device and the device tester.

[0061] The above and other features will become apparent from the following description and the attached drawings.BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Further aspects of the present disclosure will become apparent from the following description which is given by way of example only and with reference to the accompanying drawings in which:

[0063] Figure 1A is a perspective view of another example of a device made in accordance with an aspect of the present technology.

[0064] Figure IB is a top view of the device of Figure 1A.

[0065] Figure 1C is a cross-sectional side view of the device of Figure 1A.

[0066] Figure ID is an exploded perspective view of the device of Figure 1A.

[0067] Figure IE is a bottom view of the device of Figure 1A.

[0068] Figure 2A is a top perspective view of an exemplary diaphragm used in devices made in accordance with an aspect of the present technology.

[0069] Figure 2B is a bottom view of the diaphragm of Figure 2A.

[0070] Figure 2C is a top view of the diaphragm of Figure 2A.

[0071] Figure 2D is a side view of the diaphragm of Figure 2A.

[0072] Figure 2E is a cross-sectional side view of the diaphragm of Figure 2A.

[0073] Figure 3A is a top perspective view of an exemplary switch component used in devices made in accordance with an aspect of the present technology.

[0074] Figure 3B is a side view of the switch component of Figure 3A.

[0075] Figure 4 is a diagrammatic view of example of a device made in accordance with an aspect of the present technology.

[0076] Figure 5 is a diagrammatic view of example of a device made in accordance with an aspect of the present technology.

[0077] Figure 6A is a perspective view of a first device tester made in accordance with an aspect of the present technology.

[0078] Figure 6B is a cross-section of the first device tester.

[0079] Figure 6C is an end view of the first device tester.

[0080] Figure 6D is a cross-section of the first device tester illustrating how it attaches to a device made in accordance with an aspect of the present technology.

[0081] Figure 7A is a perspective view of a second device tester made in accordance with an aspect of the present technology.

[0082] Figure 7B is a perspective view of the second device tester illustrating how it attaches to a device made in accordance with an aspect of the present technology.

[0083] Figure 7C is a side view of the second device tester attached to the device.

[0084] Figure 7D is a top view of the second device tester attached to the device.

[0085] Figure 8A is a perspective view of a third device tester made in accordance with an aspect of the present technology.

[0086] Figure 8B is a cross-section of the third device tester.

[0087] Figure 8C is a cross-section of the third device tester illustrating how it attaches to a device made in accordance with an aspect of the present technology.

[0088] Figure 9A is a perspective view of a fourth device tester made in accordance with an aspect of the present technology.

[0089] Figure 9B is a cross-section of the fourth device tester illustrating how it is used with a device made in accordance with an aspect of the present technology.DETAILED DESCRIPTION

[0090] Although in the present embodiment the invasive device entry indicator is a blood vessel entry indication device, the technology is not limited to detecting blood pressure for the purpose of cannulation. In other embodiments a device embodying the technology could be employed for detecting the entry of a needle into any other liquid containing vessel or cavity of the body such as the bladder or spinal cord. Some embodiments of the technology may be intended for use with gaseous fluids.

[0091] It should therefore be noted that in this specification the word "fluid" is intended to have its normal meaning of a flowing substance such as a liquid or gas, and is not intended to be limited to a liquid such as blood.Operating Parameters

[0092] In the use case of arterial and venous cannulations, exemplary devices according to aspects of the present technology are configured such that at least one indicator is activated when pressure acting on the pressure sensor is at or above a minimum threshold. Exemplary devices according to aspects of the present technology have been developed to provide a reliable indication of correct positioning of the needle when considering that training and professional advice directs the use of a tourniquet when performing peripheral venous cannulations.

[0093] The torniquet increases Peripheral Venous Pressure (PVP), whilst surrounding tissue pressure remains about the same. PVP ranges from approximately 10 to 25 cmH20 in a healthy patient, but could be as low as 2 to 3 cmH20 in a critically unwell patient. With a tourniquet applied, even poorly or on a patient with very low blood pressure, the minimum PVP may be in the order of 25 cmH20. Subcutaneous tissue pressure can range from about 1 cmH20 to about 13.5 cmH20: subcutaneous tissue pressure around the vein / artery is up to 4 cmH20 without a tourniquet, the subcutaneous tissue pressure is up to 6 cmH20 with a tourniquet, and the subcutaneous tissue pressure is up to about 13.5 c H20 in a swollen limb.

[0094] As such, the exemplary devices of the present technology have been configured to activate the at least one indicator under all pressures that have a very high likelihood of being indicative of the needle being located in a vein or artery. In examples, the minimum threshold may be about 25 cmH20. More preferably, the minimum threshold may be about 30 cmH20.

[0095] In addition to accuracy with respect to the magnitude of the pressure, the rate of response of the device - i.e., the speed at which the indicator is activated and / or deactivated in response to a change in pressure - is considered to be highly important for clinical utility. The purpose of the device is to provide a user with feedback as to correct placement of the intravascular needle. If the indicator does not activate or deactivate in good time, there is an increased risk that the needle may be incorrectly placed. As such, exemplary devices of the present technology may be configured to activate and / or deactivate the indicator in less than about one (1) second of exceeding or dropping below the minimum threshold pressure value. Generally speaking, the smaller the pressure differential between vein and tissue, the slower the response time. As such, it is anticipated that a minimum threshold of greater than 25 cmH20 (e.g., about 30 cmH20) may be helpful in achieving a desirable response time.

[0096] Another requirement for clinical utility is that the indicator remain activated through the pressure range that may be expected from a patient while the needle is located in a vein or artery. If the pressure sensor and / or indicator fails under such expected conditions, then the usefulness of the devicediminishes, it will be appreciated that various examples of the device may be configured to operate with different levels of upper operating ranges, depending on the acceptable likelihood of failing to the detect the presence of the needle in a vein or artery of outlier patients. For example, it is estimated that 99% of all patients may fall within the pressure range of about 30 cmhhO to about 250 cmhhO. As such, it is anticipated that examples of the device may be configured to activate the indicator at all pressures from the minimum pressure to at least about 250 cmHzO.

[0097] For completeness, it should be appreciated that alternative configurations are contemplated. For example, it is estimated that 90% of all patients may fall within the pressure range of about 30 cmhhO to about 100 cmb O. In examples, the device may be configured to activate the at least one indicator at all pressures from the minimum threshold through to least 100 cmH?0. As a further example, the device may¬ be configured to configured to activate the at least one indicator from the minimum threshold through to a value above about 250 cmhhO - for example at least 500 cmhhO - in order to increase the likelihood of the device functioning for any given individual. This is not intended to exclude embodiments in which the device activates the indicator above this value, but rather emphasise an intention that the device continue to function up to at least that point.Needle Entry Indicator Device

[0098] Figures 1A to IE illustrate an exemplary device 100 for indicating entry of a needle into a body cavity, duct, or vessel of a human or non-human animal. In this example the device 100 comprises a body 120, comprising a first body portion 122 and a second body portion 124. The first body portion 122 comprises a male conduit portion 126 surrounded by an annular ridge 128 defining an annular recess 130 for receiving a cannula (not shown) such that a Luer taper connection is formed. A fluid port 132 in the male conduit portion 126 comprises an inlet 134 at an exterior of the body 120 and an outlet 136 at a first internal cavity 138 of the body 120.

[0099] Referring to Figures 1C and ID, an annular diaphragm retention member 140 is held in place internally between the first body portion 122 and the second body portion 124. The diaphragm retention member 140 in turn clamps a diaphragm 200 against the first body portion 122 to retain it in place. Referring to Figures 2A to 2E, in this example the diaphragm 200 includes an outer annular rim 202, a central portion 204, and an annular corrugation 206 extending between the annular rim 202 and the central portion 204. A cylindrical protrusion 208 extends from the central portion 204.

[0100] Referring to Figure 1C, the diaphragm 200 is installed such that the protrusion 208 faces away from the fluid port 132. In this example, the inlet 134 and the outlet 136 of the fluid port 132 are axially aligned with the central portion 204 of the diaphragm 200. The surface of the diaphragm 200 from which the protrusion 208 extends faces a second internal cavity 142. A switch unit 300, batteries 400, and spacer 600 are provided in the second internal cavity 142.

[0101] Referring to Figure 3A and Figure 3B, the switch unit 300 is made of a flexible circuit board having conductive tracks printed thereon. The switch unit 300 includes a first contact portion 302, a second contact portion 304, and a bridge portion 306 between the first contact portion 302 and the second contact portion 304. An indicator in the form of LED 500 is provided to second contact portion 304. In examples the LED 500 may output light in the visible light spectrum. However, alternative examples are contemplated in which the light is in the non-visible spectrum (e.g., near-infrared or infrared light) - for example, for use in conjunction with a night-vision device.

[0102] As shown in Figure 1C, two batteries 400 are positioned between the first contact portion 302 and the second contact portion 304. In this example the batteries 400 are alkaline in order to facilitate disposal of the device 100, particular in single-use cases. In this example the batteries 400 are stacked in series, enabling a sufficiently high voltage to be achieved while maintaining a narrow diameter footprint. For example, the batteries 400 may be LR41 button cell batteries - although it should be appreciated that this is not intended to be limiting to all embodiments of the present technology.

[0103] A spacer 600, in this example made of a silicone material, is provided between the LED 500 and the distal end of the second internal cavity 142, to assist in achieving a desired positioning of the switch unit 300 relative to the diaphragm 200 and the batteries 400.

[0104] In use, once pressure from fluid entering the first cavity 138 reaches a minimum threshold, or activation pressure, this pressure displaces diaphragm 200 such that protrusion 208 presses first contact portion 302 of the switch unit 300 into contact with the proximal battery 400 and complete the circuit to turn on LED 500. Because the circuit is only completed to activate LED 500 under targeted pressures, there is no power draw on the batteries 400 while the device 100 is not actively being used or the pressure is below the minimum threshold. This means that the battery life of the device 100 is preserved for a greater period of time than devices which constantly draw power to monitor pressure. This may allow the use of smaller capacity batteries, potentially reducing footprint and / or weight and / or cost of the device as a result, or may allow for a longer shelf-life of the device, or may avoid the need for power saving measures which would otherwise increase complexity and cost of the device.

[0105] In the use case of arterial and venous cannulations, the device 100 is configured such that the LED 500 is turned on while pressure within the first cavity 138 (i.e., acting against diaphragm 200) is within the range of about 30 cmHzO to at least 500 cmH20. For completeness, this configuration means that: (1) the LED 500 is turned on once pressure reaches 30 cmHzO, (2) the LED 500 remains on while the pressure is at least 30 cmHzO or above, (3) the device is capable of keeping the LED 500 activated while experiencing pressure of 30 cmHzO up to at least 500 cmHzO, and (4) the LED 500 is deactivated when the pressure is below 30 cmHzO.

[0106] In examples, the second body portion 124 comprises air ports 144 between the second cavity 142 and an exterior of the body 120. The air ports 144 allow the pressure in the second cavity 142 to equalise with atmosphere, allowing for use of the device 100 at various altitudes and enabling transport at outlier pressures (for example, in aircraft) without damaging the membrane of the diaphragm. In this example the air ports 144 are provided through an end wall 146 of the second body portion distal from the fluid port 132. Positioning of the air ports 144 at this location ensures they are away from the welding site between the first body portion 122 and the second body portion 124.

[0107] External ridges 148 on the exterior of the second body portion 124 provides grip, whether by a user's fingers or a holder as generally described with reference to Figures 6A and 6B.

[0108] Devices constructed in the manner described above with respect to Figures 1A to IE were tested to ensure correct operation. A hydraulic test jig was established, comprising a cylindrical reservoir having a dry break valve into which the devices were inserted to expose the diaphragm to pressure within the reservoir. The reservoir was filled to a fill line with simulated blood, and pressurised to a targeted pressure value using a pneumatic pump via a Schrader valve into a headspace. Three devices were tested at 20 cmHzO and 25 cmHjO to ensure the device does not activate below the design pressure of 30 cmh O. The testing procedure was repeated, with the test pressure increased in increments of 10 cmh O from SOcmF O to 250cmH2O. After testing at 250cmH2O, the test pressure increased in SOcmF O increments until the maximum pressure of SOOcmFhO was reached. This was repeated three times for each device. This testing procedure was then repeated with three devices.

[0109] Initially, the response time was going to be recorded for each test to ensure activation / deactivation times were less than one second. However, it was observed that the LED activation was near instantaneous, and results were primarily dependent on the test operator's reaction time which would give misleading results. The decision was made to instead only record the activation and deactivation using a pass / fail criteria based on the device activating and deactivating immediately in response to the pressure changes.

[0110] Overall, all three devices functioned correctly. The LED did not activate at pressures below 30 cmH20. The devices all worked consistently from the design pressure of 30 cmH20, throughout the range of pressures, up to the maximum pressure of 500 cmH20. All three devices also successfully deactivated instantly when the dry break valve was closed.

[0111] Figure 4 schematically illustrates another exemplary device 1000 for indicating entry of a needle into a human or animal vessel or cavity. In this example, the device 1000 comprises a digital pressure sensor 1100 in fluid communication with a needle bore of the needle in use. In examples, the digital pressure sensor 1100 may be configured as a pressure switch, outputting a signal to activate an indicator 1200 (e.g., an LED) when the sensed pressure is within a target pressure range - for example betweenabout 30 cmHzO to about 500 cmHzO. In an alternative example, the pressure sensor 1100 may output a signal indicative of pressure to a controller 1300, and the controller may selectively activate the indicator 1200 based on a determination of whether the pressure is from about 30 cmhhO to about 500 cmHjO.

[0112] Figure 5 schematically illustrates another exemplary device 2000 for indicating entry of a needle into a human or animal vessel or cavity, more particular during central line (or central venous catheter) placement. In central line placement, complications with accidental arterial puncture are widely recognised. In a first embodiment, the device 2000 comprises a first pressure sensor arrangement 2100a in fluid communication with a needle bore of the needle in use, having two diaphragms, each diaphragm configured to be deformable under fluid pressure from a first configuration to a second configuration. The first diaphragm is configured to be deformed to the second configuration when the pressure is within a first pressure range, and the second diaphragm is configured to be deformed to the second configuration when the pressure is within a second pressure range. In examples, the first pressure range may be indicative of central venous pressure (CVP). In examples the second pressure range may be indicative of non-CVP. In examples, the first pressure range may be from about 3 cmhhO to about 40 cmHzO. in examples the second pressure range may be from about 40 cmhhO to about 500 cmHzO.

[0113] The device 2000 includes circuitry 2200 to selectively control activation of an indicator 2300 having first indicator output 2302a and a second indicator output 2302b, depending on actuation of the first and / or second diaphragm. For example, the indicator 2300 may be a multicolour LED capable of selectively outputting green light and red light. In use, the green light is activated when the pressure is within the first range - i.e., indicating that the needle is correctly positioned within the vein. The red light is activated when the pressure increases to the second range - i.e., indicating that an arterial puncture has occurred, to guide remedial action.

[0114] In an alternative example, the device 2000 comprises a second pressure sensor arrangement 2100b in fluid communication with a needle bore of the needle in use, in the form of a digital pressure sensor. In examples the pressure sensor 2100b may output a signal indicative of pressure to a circuitry 2200 comprising a controller, and the controller 2200 may selectively activate the first indicator output 2302a or the second indicator output 2302b based on a determination of whether the pressure is within the first pressure range or the second pressure range.

[0115] Although in the present embodiment the diaphragms are formed of non-conductive material in other embodiments diaphragms may be formed of an electrically conductive rubber material. For example, a non-conductive diaphragm may be provided with a conductive coating, conductive particles throughout or a conductive connector.

[0116] In the present specification the phrase 'touches a surface' is intended in its broadest sense to include both at least merely contacting a surface (in the event that the diaphragm is conductive) and also applying pressure thereto (in the event that the diaphragm activates a pressure-operated switch.Device Tester

[0117] In examples, a device tester may be provided to enable a user to test operation of a device 100 prior to use. In examples, the device tester may be delivered to the user pre-assembled with the device 100, for example within a sealed package (e.g., a medical pouch). In examples, the sealed package may be deformable so as to permit operation of the device tester within the sealed package, and is at least translucent to enable operation of the indicator to be viewed. For example, the sealed package may comprise a base portion and a translucent or transparent window portion. This allows for the device 100 to be tested prior to opening the sealed package - facilitating ease of disposal should the device 100 fail testing.

[0118] Turning to Figures 6A to 6D, a first exemplary device tester 600 according to an aspect of the present technology comprises a deformable hollow bulb 602 having an interior 604, and connector portion 610. In this example the bulb 602 may be overmoulded or inserted onto the connector portion 610. The connector portion 610 comprises a tubular connector 612 having inner bore 614 with a bore surface 616 that is adapted to snugly house and form an airtight fit with a male conduit portion 126 of a device 100 (see, Figure 6D).

[0119] Prior to use of device 100, a user may squeeze bulb 602 so as to inject air into device 100 and observe if the indicator thereof is powered, and to thereby test whether or not device 100 is operational. Bulb 602 is sized so as to inject sufficient air into device 100 to deform the diaphragm of device 100 and operate its indicator, whilst at the same time inject insufficient air to the damage the diaphragm.

[0120] In this example, the connector portion 610 comprises an air bleed feature in the form of a recess 618 (also referred to herein as a groove 618) in the bore surface 616 extending from an external point 622 to an internal point 622. In use, when male conduit portion 126 of a device 100 is inserted into inner bore 614, the groove 618 provides an air bleed between the interior 604 of the bulb 602, and the external environment.

[0121] The cross-sectional area of the groove 618 is such that sufficient pressure may still build through fluid port 132 to activate the device 100 when the bulb 602 is deformed - i.e., the cross-section of the groove 618 is substantially smaller than the diameter of fluid port 132. The air bleed may serve several purposes. For example, where the device 100 delivered to the user pre-assembled with the device tester 600, the air bleed may enable the air pressure in the bulb 602 to equalise to the surrounding environmental air pressure when at altitude (e.g., during air-shipping) so that the device 100 doesn'tactivate. Further, the air bleed may allow gas to enter the bulb 602 during gas sterilisation - e.g., Ethylene Oxide ("EtO") sterilisation.

[0122] Turning to Figures 7A to 7D, a second exemplary device tester 700 according to an aspect of the present technology comprises a bulb 710, and connector portion 750. In this example, a bulb connector portion 712 may be overmoulded or inserted onto the connector portion 750, with a deformable hollow bulb portion 714 extending from the bulb connector portion 712. The connector portion 750 comprises a tubular connector 752 having inner bore 754 that is adapted to snugly house and form an airtight fit with a male conduit portion 126 of a device 100 (see, Figure 7B).

[0123] In examples, the longitudinal cross-sectional shape of the bulb 710 is substantially flat - i.e., having a length along a first axis (e.g., width) that is greater than a length along a second axis perpendicular to the first axis (e.g., height). In the illustrated example the cross-sectional shape is substantially ovaloid, but alternative shapes are contemplated (e.g., stadium or oblong). For an oval shape, reference to a lateral surface 716 of the bulb 710 should be understood to mean a region spanning over a vertex of the oval, while reference to superior or inferior surface portions 718 should be understood to mean a region spanning over a co-vertex of the oval.

[0124] In examples the bulb 710 comprises at least one airbleed aperture 720, providing a flow passage between the interior and exterior of the bulb 710. In examples, an airbleed aperture 720 may be provided on one or both of the superior / inferior surface portions 718. In examples, the airbleed aperture 720 may be provided in a locating feature 722 (e.g., a curved depression) configured to aid in positioning of a user's digits relative to the airbleed aperture 720. In use, a user's digit(s) cover the airbleed aperture(s) 720 while gripping the bulb 710, blocking the escape of air while the bulb 710 is deformed and the device 100 is tested.

[0125] In examples the at least one airbleed aperture 720 may be substantially centred in the surface portion in which it is provided (as shown in FIG. 7D). It is envisaged that this may assist with intuitive use of the device tester 700, increasing the likelihood of the airbleed aperture 720 being covered by the user's finger when the device tester 700 is grasped.

[0126] It is envisaged that the flat shape of the bulb 710 may assist with maintaining the orientation of the device tester 700 within a flat medical pouch, restricting rotation which might otherwise reduce the ease of the user locating the air bleed aperture 722 while within the pouch.

[0127] For completeness, alternative embodiments are contemplated in which (a) the bulb 710 is not flat perse (e.g., may be substantially circular in cross-section, as depicted in Figure 6A), and / or (b) the airbleed aperture 720 may be positioned in another location on the bulb 710 (e.g., in an end of the bulb 710 distal from the tubular connector 752).

[0128] Figures 8A to 8C illustrate a third device tester 800 according to an aspect of the present technology, for testing of a device 100 including air ports 144 (see, Figure IE). The third device tester 800 comprises a hollow receptacle portion 802 having an interior 804, and an actuator portion 806 (in the example a substantially cylindrical projection) configured to be gripped by the user. The interior 804 is sized and shaped to be fitted snugly over the second body portion 124 of the device.

[0129] The third device tester 800 comprises a deformable portion 808 between the receptacle portion 802 and the actuator portion 806. In use, the user grips the actuator portion 806 and pulls to create a suction effect on the diaphragm 200 through air ports 144. This activates the device 100.

[0130] In examples, as shown in Figures 8B and 8C, the actuator portion 806 may comprise an actuator bore 810. The actuator bore 810 may allow for the device 100 to be used without removal of the third tester device. Further, the actuator bore 810 may allow for the passage of gas, such as during EtO sterilisation. In such embodiments, at least a portion of the actuator portion 806 may be deformable, such that the actuator bore 810 collapses and seals when gripped by the user for testing of the device 100. In alternative embodiments the actuator port 806 may be solid.

[0131] Figures 9A and 9B illustrate a fourth device tester 900 comprising a shaft 902 configured to be inserted to a male conduit portion 126 of a device 100, to mechanically depress diaphragm 200 and activate the device 200 for testing purposes. In examples (as shown in Figure 9B), a stopper 904 is provided on shaft 902 so as to prevent excessive pressure being placed on the diaphragm 200 and consequential damage thereto. In examples, the end of the shaft 902 configured to come in contact with the diaphragm 200 is rounded to reduce the likelihood of damage. In the illustrated example, a grip portion 906 having a greater cross-section than the shaft 902 is provided for ease of grasping by the user.

[0132] In examples, a tester device 900 (and more particularly shaft 902) may be incorporated into packaging in which the device 100 is supplied. It is envisaged that the shaft 902 may be actuated by a user to test the device 100 prior to opening the packaging. In examples, the packaging may be configured to maintain the position of the shaft 902 until actuated, and / or guide the shaft 902 when actuated. In examples the shaft 902 may be integrally formed with the packaging.

[0133] All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the field of endeavour in any country in the world.

[0134] Unless the context clearly requires otherwise, throughout the description and the claims, thewords "comprise", "comprising", and the like, are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense, that is to say, in the sense of "including, but not limited to".

[0135] The present disclosure may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, in any or all combinations of two or more of said parts, elements or features. Where in the foregoing description reference has been made to integers or components having known equivalents thereof, those integers are herein incorporated as if individually set forth.

[0136] It should be noted that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the spirit and scope of the present disclosure and without diminishing its attendant advantages. It is therefore intended that such changes and modifications be included within the present disclosure as defined by the appended claims.

Claims

CLAIMS1. A device tester for an invasive device entry indicator comprising a pressure sensor configured to be in fluid communication with a needle bore of the needle in use, at least one selectively activated indicator, wherein the invasive device entry indicator is configured to activate the indicator while pressure acting on the pressure sensor is above a minimum threshold, the device tester comprising:a hollow deformable portion; anda fluid port configured to fluidly connect an interior of the hollow deformable portion to the pressure sensor in use,wherein the hollow deformable portion comprises at least one air bleed aperture between the interior of the hollow deformable portion and external atmosphere.

2. The device tester of claim 1, wherein the hollow deformable portion comprises a first air bleed aperture in a first surface portion, and a second air bleed aperture in a second surface portion opposing the first surface portion.

3. The device tester of claim 1 or claim 2, wherein the at least one air bleed aperture is provided in a locating feature.

4. The device tester of claim 3, wherein the locating feature includes a depression surrounding the air bleed aperture.

5. The device tester of claims 1 to 4, wherein a longitudinal cross-sectional shape of the hollow deformable portion is substantially flat.

6. The device tester of claims 1 to 6, wherein the longitudinal cross-sectional shape is substantially ovaloid.

7. The device tester of claim 6, wherein the at least one air bleed aperture is located in a region proximal to a co-vertex of the hollow deformable portion.

8. The device tester of claims 1 to 7, wherein the at least one air bleed aperture is substantially centred between sides of the hollow deformable portion.

9. A kit of parts comprising:an invasive device entry indicator comprising a pressure sensor configured to be in fluid communication with a needle bore of the needle in use, at least one selectively activated indicator, wherein the invasive device entry indicator is configured to activate the indicator while pressure acting on the pressure sensor is above a minimum threshold; andthe device tester of any one of claims 1 to 8.

10. A kit of parts comprising:an invasive device entry indicator comprising a pressure sensor configured to be in fluid communication with a needle bore of the needle in use, at least one selectively activated indicator, wherein the invasive device entry indicator is configured to activate the indicator while pressure acting on the pressure sensor is above a minimum threshold;the device tester of any one of claims 1 to 8; anda sealed package containing the invasive device entry indicator and the device tester, wherein at least a portion of the sealed package is deformable so as to permit operation of the device tester within the sealed package.

11. A method of testing an invasive device entry indicator comprising a pressure sensor configured to be in fluid communication with a needle bore of a needle in use, and at least one selectively activated indicator, wherein the invasive device entry indicator is configured to activate the indicator while pressure acting on the pressure sensor is above a minimum threshold, the method comprising:providing a device tester to the invasive device entry indicator, the device tester comprising: a hollow deformable portion; anda fluid port configured to fluidly connect an interior of the hollow deformable portion to the pressure sensor in use,wherein the hollow deformable portion comprises at least one air bleed aperture between the interior of the hollow deformable portion and external atmosphere; positioning a digit of a user over the at least one air bleed aperture; anddeforming the hollow deformable portion to apply increased pressure to the pressure sensor of the invasive device entry indicator.

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