Access needle indication system for positioning and accessing a subcutaneous medical device

Abstract

Embodiments disclosed herein relate to access devices configured to access a subcutaneous medical device. The access device can include a needle supported by a needle hub, and in some embodiments a housing in slidable engagement with the needle hub and configured to align the needle axis at a predetermined angle. The access device can include an indicator system configured to detect when the needle is properly aligned with a target window of the port. This can allow for a port profile that is smaller, shallower, with a smaller target window, while mitigating mis-sticks. The indicator system can be incorporated into the access device with little or no increase in the overall size of the access device. The indicator system can employ various modalities, including capacitive, inductive, magnetic, thermal, acoustic, or radio frequency (RF).

Description

Background Technology

[0001] Subcutaneous medical devices such as "ports" provide a convenient method for repeated vascular access. Ports can be implanted in the body and allow the infusion of medications, parenteral solutions, blood products, or other fluids. Ports are also used for blood sampling. In typical practice, the port is implanted subcutaneously in the body, and a catheter is connected to the port in fluid communication. The catheter is guided into the vascular system to deliver or remove fluid within it. To deliver fluid, caregivers locate the septum of the port by palpating the patient's skin.

[0002] Port access is achieved by percutaneously inserting a needle (usually a non-cored needle) through the septum of the port and into the port's reservoir chamber. Fluid containing a drug or other beneficial substance can then be administered into the port's chamber via rapid concentration or continuous infusion. The fluid then flows through the chamber into the catheter and eventually reaches the remote location where fluid is needed.

[0003] Ports, especially port septa, need to be of a certain size for successful palpation. However, these relatively large ports can affect wound healing and cause skin stretching and scarring. Furthermore, since any slight movement between the palpation port and the alignment needle can lead to accidental puncture and discomfort for the patient, both require experience and training. Smaller or lower-profile ports can improve wound healing, reduce scarring, and improve aesthetics, thus improving the patient's overall quality of life. However, these smaller, lower-profile ports, especially port septa, are more difficult to locate by palpation and increase the risk of accidental puncture.

[0004] This paper discloses an entry device and related methods, which are configured to indicate when a pin is correctly aligned with a port, enabling improved alignment accuracy and the creation of smaller, lower profile ports. Summary of the Invention

[0005] The present invention discloses an access component configured for detecting and accessing a subcutaneous medical device. The access component includes a needle supported by a needle bushing and an indicator system. The indicator system includes a capacitive sensor and an LED light. The capacitive sensor is configured to detect changes in the dielectric constant between the subcutaneous medical device and surrounding tissue, and the LED light is configured to indicate when the needle is aligned with the subcutaneous medical device.

[0006] In some embodiments, the access component further includes a housing that supports and slidably engages with the needle bushing, the needle bushing being configured to switch between a retracted position and an extended position. The housing defines a bottom surface configured to engage the skin surface, and a sensor is disposed in the bottom surface. An LED is disposed on either the housing or the needle bushing. The subcutaneous medical device is a port comprising a port body and a septum, the port body and septum cooperating to define a reservoir. A needle is configured to penetrate the septum to enter the reservoir beneath the septum when aligned with the subcutaneous medical device. The subcutaneous medical device includes a material disk that increases the difference in dielectric constant with the surrounding tissue. The material disk includes one of platinum, silver, tungsten, gold, cobalt, titanium, silicon dioxide, or zirconium oxide. The disk is disposed below the reservoir and defines a diameter extending to the same diameter as the reservoir. The sensor is capable of detecting changes in dielectric constant at depths between 0.15 inches and 3 inches below the skin surface.

[0007] The present invention also discloses a vascular access system comprising: an access device including a needle supported by a needle bushing and including a voltmeter sensor and an indicator; and a subcutaneous port device including a port body defining a reservoir and a needle diaphragm disposed above the port body, the port body including an induction coil configured to sense current in the voltmeter sensor to activate the indicator and provide an alarm.

[0008] In some embodiments, the induction coil is capable of sensing current within a range of 0.15 inches to 3 inches along an axis extending perpendicular to the skin surface. The alarm is one of a visual, audible, or tactile alarm. The indicator is an LED bulb illuminated by current induced by the induction coil from a voltmeter. In some embodiments, the pulse-entry system also includes an integrated circuit or a 555 timer configured to receive a first voltage from the voltmeter and provide a first output to activate the indicator, and to receive a second voltage from the voltmeter and provide a second output to activate the indicator.

[0009] The present invention also discloses a method for accessing a subcutaneous port, the method comprising: engaging the bottom surface of a housing with a skin surface, slidably engaging the housing with a needle bushing supporting a needle, the housing aligning the axis of the needle relative to the skin surface at a predetermined angle, detecting a first dielectric constant of tissue disposed below the bottom surface of the housing, sliding the housing parallel to the skin surface, detecting a second dielectric constant different from the first dielectric constant, activating an indicator to provide an alarm, and sliding the needle bushing relative to the housing to allow the needle to penetrate the skin surface and enter the subcutaneous port.

[0010] In some embodiments, the alarm includes a visual, auditory, or tactile alarm. In some embodiments, actuating the indicator to provide the alarm includes illuminating an LED bulb to align the axis of the indicator needle with a reservoir at the subcutaneous port. The bottom surface of the housing includes a capacitive sensor configured to detect the dielectric constant of tissue disposed beneath the bottom surface. The subcutaneous port includes a material disk configured to provide a second dielectric constant. The disk includes one of platinum, silver, tungsten, gold, cobalt, titanium, silicon dioxide, or zirconium oxide. In some embodiments, the method further includes detecting one of a first or second dielectric constant at a depth between 0.15 inches and 3 inches below the skin surface. The predetermined angle is less than or equal to 90° relative to the skin surface.

[0011] The present invention also discloses a method for detecting and accessing a subcutaneous medical device, the method comprising: providing an access device having a needle extending along an axis and supported by a needle bushing; and an indicator system including a voltmeter sensor and an indicator; aligning the axis of the needle with a skin surface at a predetermined angle; sliding the access device parallel to the skin surface; sensing a current in the voltmeter sensor to activate the indicator; and penetrating the skin surface with the needle to access the subcutaneous medical device.

[0012] In some embodiments, the method further includes a housing slidably engaged with a needle bushing and including a bottom surface configured to engage with a skin surface and align with the axis of the needle at a predetermined angle. A voltmeter sensor is disposed in one of the bottom surfaces of the needle bushing or the housing. The predetermined angle is equal to or less than 90° relative to the skin surface. A subcutaneous medical device is a port including an induction coil disposed therein, the induction coil being configured to sense a current in the voltmeter sensor. In some embodiments, the method further includes receiving a first voltage from the voltmeter sensor and providing a first output to activate an indicator, and receiving a second voltage from the voltmeter sensor and providing a second output to activate the indicator. The first output activates the indicator at a first rate, and the second output activates the indicator at a second rate different from the first rate.

[0013] The present invention also discloses an entry system configured for detecting alignment with a subcutaneous medical device. The entry system includes a needle supported by a needle bushing and an indicator system having an acoustic transducer sensor and an LED light. The acoustic transducer sensor is configured to emit an acoustic signal and detect a first reflected signal. The LED light is arranged on the needle bushing and configured to indicate when the axis of the needle is aligned with the subcutaneous medical device.

[0014] In some embodiments, the access system further includes a housing that supports and slidably engages with the needle bushing, the needle bushing being configured to switch between a retracted position and an extended position. The housing defines a bottom surface configured to engage with the skin surface, in which an acoustic transducer sensor is disposed. The subcutaneous medical device is a port comprising a port body and a diaphragm that cooperate to define a reservoir. The needle is configured to penetrate the diaphragm to enter the reservoir beneath the diaphragm when aligned with the subcutaneous medical device. In some embodiments, an acoustic signal impinges on the subcutaneous medical device to provide a second reflected signal, distinct from a first reflected signal, which triggers an LED to illuminate.

[0015] In some embodiments, the first reflected signal is relatively weak or absent compared to the second reflected signal. In some embodiments, the first reflected signal indicates a first distance, and the second reflected signal indicates a second distance different from the first distance, the second distance being within a predetermined distance range, to indicate the presence of a subcutaneous medical device. The subcutaneous medical device includes a material disk that amplifies the difference between the first and second reflected signals. The material disk includes one of platinum, silver, tungsten, gold, cobalt, titanium, silicon dioxide, or zirconium oxide. The disk is disposed below a reservoir and defines a diameter extending to the same diameter as the reservoir.

[0016] These and other features of the concepts provided herein will become more apparent to those skilled in the art in light of the accompanying drawings and the following description, which disclose specific embodiments of such concepts in more detail. Attached Figure Description

[0017] A more specific description of the invention will be presented with reference to specific embodiments of the invention illustrated in the accompanying drawings. It should be understood that these drawings depict only typical embodiments of the invention and should not be considered as limiting its scope. Exemplary embodiments of the invention will be described and explained with additional features and details using the drawings, wherein:

[0018] Figure 1 An exemplary usage environment of the access system according to an embodiment of the present invention is illustrated.

[0019] Figure 2A The illustration shows a side view of an exemplary implantable medical device according to an embodiment of the present invention.

[0020] Figure 2B The illustration shows a side view of the entry component according to an embodiment of the present invention.

[0021] Figures 3A-3C The illustration shows a side view of an entry system according to an embodiment of the present invention.

[0022] Figures 4A-4CThe illustration shows a side view of an entry system according to an embodiment of the present invention.

[0023] Figures 5A-5C The illustration shows a floor plan of an entry system according to an embodiment of the present invention.

[0024] Figures 6A-6C The illustration shows a side view of an entry system according to an embodiment of the present invention. Detailed Implementation

[0025] Referring now to the accompanying drawings, in which the same structures have the same reference numerals. It should be understood that the drawings are illustrations and schematic representations of exemplary embodiments of the invention and are neither limiting nor necessarily drawn to scale. Before disclosing some specific embodiments in more detail, it should be understood that the specific embodiments disclosed herein do not limit the scope of the concepts provided herein. It should also be understood that features of specific embodiments disclosed herein can be readily separated from those specific embodiments and optionally combined with or substituted for features of any of the many other embodiments disclosed herein.

[0026] Regarding the terminology used herein, it should also be understood that these terms are for the purpose of describing certain specific embodiments, and that these terms do not limit the scope of the concepts presented herein. Ordinal numbers (e.g., first, second, third, etc.) are generally used to distinguish or identify different features or steps in a set of features or steps, and do not provide for sequential or numerical limitations. For example, features or steps “first,” “second,” and “third” do not necessarily appear in that order, and a particular embodiment including such features or steps is not necessarily limited to three features or steps. Markings such as “left,” “right,” “front,” “back,” “top,” “bottom,” “forward,” “reverse,” “clockwise,” “counterclockwise,” “up,” “down,” or other similar terms such as “upper,” “lower,” “back,” “front,” “vertical,” “horizontal,” “proximal,” “farthest,” etc., are used for convenience and are not intended to imply, for example, any particular fixed position, orientation, or direction. Rather, such markings are used to reflect, for example, relative position, orientation, or direction. The singular forms “a,” “an,” and “the” include plural references unless the context clearly indicates otherwise. Furthermore, as used herein, including in the claims, the words “comprising,” “having,” and “possessing” shall have the same meaning as the word “including.”

[0027] The terms "proximal," "proximal portion," or "proximal portion" of a needle, as disclosed herein, include the portion of the needle intended to be close to the clinician when the needle is used on a patient. Similarly, the term "proximal length" of a needle includes the length of the needle intended to be close to the clinician when the needle is used on a patient. For example, the term "proximal end" of a needle includes the end of the needle intended to be close to the clinician when the needle is used on a patient. The proximal portion, proximal portion, or proximal length of a needle may include the proximal end of the needle; however, the proximal portion, proximal portion, or proximal length of a needle does not necessarily include the proximal end of the needle. That is, unless the context otherwise suggests, the proximal portion, proximal portion, or proximal length of a needle is not the distal portion or distal length of the needle.

[0028] The term "distal," "distal portion," or "distal part" of a needle, as disclosed herein, includes a portion of the needle intended to be near or within the patient when used with the needle. Similarly, for example, the "distal length" of a needle includes the length of the needle near or within the patient when used with the needle. For example, the "distal end" of a needle includes the end of the needle near or within the patient when used with the needle. The distal portion, distal end, or distal length of the needle may include the distal end of the needle; however, the distal portion, distal part, or distal length of the needle does not need to include the distal end of the needle. That is, unless the context otherwise suggests, the distal portion, distal part, or distal length of the needle is not the distal end portion or distal length of the needle.

[0029] As used herein, an "integrated circuit" ("IC") may include one or more of the following: analog-digital or mixed circuits, monolithic integrated circuits, silicon chips, semiconductor chips, "chips", "microchips", "555" timers, processors, non-transitory memory, etc.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art.

[0031] Embodiments of the present invention generally relate to access systems configured to indicate proper alignment with an implantable medical device placed within a patient to mitigate accidental puncture. Examples of such medical devices include implantable vascular access ports, although a variety of other implantable devices may benefit from the use of this system. Once the port is implanted under the skin, it can be difficult to locate, particularly with low-profile port septa, and even more difficult to properly align the access needle. Therefore, access devices are needed to confirm proper alignment and mitigate accidental puncture.

[0032] Figure 1An exemplary use environment of an access system 100 according to one embodiment is illustrated. The access system 100 includes an access device 150 and a subcutaneous medical device, such as a vascular access port (“port”) 200. As used herein, port 200 serves as an exemplary medical device; however, it should be understood that embodiments of system 100 may also include other implantable medical devices, such as catheters, stents, pumps, combinations thereof, etc. Furthermore, port 200 is shown throughout the figures as having certain features, such as diaphragmatic protrusions, suture holes, etc., which are optional. Additionally, port 200 is shown as having a certain shape, which is also optional. It should be understood that the access system described herein can be used with any type of vascular access port or other implantable medical device. Port 200 is subcutaneously implanted in the patient 10, and catheter 300 fluidly connects port 200 to the patient 10's vascular system 20.

[0033] The access device 150 can be percutaneously accessed through port 200 to deliver medication or other fluids through catheter 300 to port 200 and the patient's vascular system 20. As used herein, the access device 150 may include any infusion device, extension device, or needle device that can be used to deliver medication or other fluids through fluid access to the implantation port 200.

[0034] Figure 2A-2B Further details of an access system 100 for aligning an access device 150 with an implantable medical device 200 (e.g., a port), according to one embodiment, are illustrated. Figure 2A As shown, port 200 includes a body 212 and a needle-permeable septum 214, the septum 214 cooperating with the body 212 to define a fluid reservoir 216. Optionally, the port body 212 may include a suture hole 208. An indwelling catheter 300 is fluidly connected to the outlet 218 of the reservoir 216 of port 200 so that medication or other fluids delivered percutaneously to the port reservoir 216 via the needle 152 of the access device 150 (through needle puncture of the septum 214) can be delivered to the vascular system 20 of the patient 10.

[0035] like Figure 2B As shown, the access device 150 may include a needle 152 supported by a needle bushing 154. The needle 152 may be a coreless needle, a non-traumatic needle, a "flexible" needle, or a similar needle configured to pierce the skin surface 90 and the port septum 214 to access a reservoir 216 of a subcutaneous port 200. The needle 152 may define a lumen 156 that provides fluid communication between a distal opening 158 located adjacent to the distal tip of the needle 152 and an extension leg 160 extending from the needle bushing 154.

[0036] In one implementation scheme, such as Figures 6A-6CAs shown, needle 152A may include a “flexible” needle 152A or a cannula. The flexible needle 152A may be inserted into port 200, as described herein. Once the distal opening 158 is positioned within reservoir 216, a portion of the needle adjacent to the skin surface may be configured to bend, such that the proximal portion of the needle positioned outside the body can lie flat on the skin surface. In one embodiment, a portion of needle 152A may be heat-treated to make it ductile to allow the needle to bend. This can contrast with the untreated portion of needle 152A that remains substantially rigid or stiff. In one embodiment, a portion of needle 152A may include a different material or may include a different physical structure (e.g., braid, coil, perforation, etc.) to allow that portion of needle 152A to bend. In one embodiment, entry device 150 may also include a cannula needle 162, or a similar device disposed within the needle lumen, to support the needle during insertion and prevent premature buckling of the flexible portion of the needle. Once needle 152A has been inserted, cannula 162 can be removed and the needle can be bent to lie flat on the skin surface, as described herein. Advantageously, the "flexible" needle 152A can be inserted into ports 200 arranged at different depths below the skin surface, while the remainder of needle 152A can be bent to lie flat against the skin surface.

[0037] In one embodiment, the access device 150 may further include a housing 170 configured to support and slidably engage one of the needle 152 or the needle bushing 154. The housing 170 may define a bottom surface 172 configured to engage a patient's skin surface 90. The bottom surface 172 may be aligned with the axis (a) of the needle 152 relative to the skin surface 90. In one embodiment, the bottom surface 172 may be aligned with the axis of the needle 152 relative to the skin surface 90 at a predetermined angle (θ). The predetermined angle (θ) may be less than or equal to 90° relative to the skin surface 90. Advantageously, the predetermined angle (θ) may be aligned with the distal needle opening 158 for access to the reservoir.

[0038] like Figure 2A As shown, in an embodiment where the predetermined angle (θ) is substantially 90° relative to the skin surface 90°, the diaphragm 214 provides the maximum possible target window (x) for entry into the reservoir 216, mitigating accidental puncture. Furthermore, the needle 152 can traverse the diaphragm 214 with minimal vertical distance, extending the lifespan of the diaphragm 214. However, when the needle 152 forms an angle <90° relative to the skin surface 90°, the target window (y) is significantly reduced. As will be understood, without the benefits of the embodiments disclosed herein, any unintentional deviation by the user from a 90° angle can significantly increase the probability of accidental puncture.

[0039] In one embodiment, with a predetermined angle (θ) of <90° relative to the skin surface, the distal needle opening 158 can be fully positioned within the reservoir 216, requiring a shorter overall vertical height of the reservoir 216 to provide a lower overall profile for the port 200. Further details of such ports can be found in WO2020 / 028847, filed August 2, 2019, which is incorporated herein by reference in its entirety. In embodiments described herein, where a 90° angle is maintained or where the predetermined angle (θ) is intentionally less than 90°, the embodiments can improve accuracy for the user and reduce accidental punctures by the low-profile port.

[0040] In one embodiment, the needle bushing 154 is slidably engaged with the housing 170 along an axis extending parallel to the axis (a) of the needle 152. Thus, the needle bushing 154 can be in a retracted position ( Figure 2B , 3B ) and extended position ( Figure 3C The needle 152 can be switched between the retracted and extended positions. In the retracted position, the distal tip of the needle 152 is positioned above the bottom surface 172 of the housing 170, allowing the needle 152 to be positioned within the housing 170. Advantageously, the needle 152 in the retracted position can mitigate accidental needle prick injuries. In the extended position, the distal tip of the needle 152 can extend below the bottom surface 172 of the housing 170, allowing the needle 152 to penetrate the skin surface 90 that engages with the bottom surface 172.

[0041] like Figures 3A-3C As shown, in use, the clinician engages the bottom surface 172 of the housing 170 with the skin surface 90 and manipulates the insertion device 150 until the needle 152 is aligned with the target window of the septum 216 arranged subcutaneously beneath it. The clinician can then retract the needle sheath 154 from its retracted position. Figure 3B Slide to the extended position ( Figure 3C This allows the needle 152 to penetrate the port diaphragm 216, and the distal opening 158 to enter the reservoir 216.

[0042] As described herein, positioning the port 200 can be performed by palpating the patient's skin surface to align the needle 152 with the port septum 216. However, this requires the port 200 and / or the port septum 216 to be large enough to be successfully palpated. During the placement of such a large port, the skin is stretched, leading to prolonged wound healing, increased scarring, and increased discomfort, which is detrimental to the patient.

[0043] In one embodiment, the access device 150 may include an indicator system 180 configured to instruct a clinician when the needle 150 is aligned with the target window of the port 200. Advantageously, the indicator system 180 can indicate to the clinician when the needle 150 is aligned with the port 200 without requiring any palpation of the port 200. Furthermore, the indicator system 180 can achieve highly precise alignment of the needle 152 with the port 200 to allow for smaller, lower-profile ports 200, or angled insertion ports. These smaller ports can improve wound healing, reduce scarring, and decrease patient discomfort.

[0044] Advantageously, the indicator system 180 is included within the insertion device 150, i.e., within the needle bushing 154 and / or housing 170, to provide convenient indication of proper alignment with the port reservoir 216 at the insertion site. This eliminates the need for clinicians to divert their attention from the insertion site to confirm alignment. Furthermore, the insertion device 150 requires no additional imaging equipment, console, monitor, or coupled computing device for alignment confirmation. This further reduces the cost and expertise required to operate additional devices.

[0045] In one embodiment, the indicator system 180 may include an indicator 182 configured to alert a user when the needle 152 is aligned with the port 200 via a visual, auditory, or tactile alarm. For example, the entry device may include an LED indicator 182 configured to emit light or change color when the needle 152 is correctly aligned. In one embodiment, the LED may project an image or symbol onto the skin surface 90. In one embodiment, the entry device 150 may provide a vibratory or audible alarm when the needle 152 is correctly aligned. In one embodiment, either the needle bushing 154 or the housing 170 may be formed of a transparent or translucent material, allowing light from the LED 182 to refract through it.

[0046] In one embodiment, the indicator system 180 may include one or more sensors 184 disposed within the access device 150 and configured to detect the presence of a port 200 disposed below it. When the presence of port 200 is detected, the indicator system 180 may activate an indicator to alert a clinician that the axis of needle 152 is correctly aligned with port reservoir 216. Optionally, the indicator system 180 may include a power supply configured to power the sensors 184, the indicator 182, and any associated circuitry.

[0047] like Figures 3A-3C As shown, in one embodiment, the sensor may be disposed in the bottom surface 172 of the housing and configured to contact the skin surface 90. Figures 4A-4CAs shown, in one embodiment, sensor 184 may be arranged in needle sleeve 154. In one embodiment, as Figures 5A-5C As shown, sensor 184 may be an array of two or more sensors arranged around axis (a) of needle 152. In one embodiment, sensor 184 may define an annular shape and be arranged circumferentially around axis (a) of needle 152.

[0048] Figures 4A-4C An embodiment of an access device 150 including an indicator system 180 disposed within a needle sheath 154 is shown. As shown, the access device 150 can be configured without a housing 170. A clinician can guide the access device 150 above the skin surface 90. Figure 4A ), until sensor 184 detects that the axis of needle 152 is correctly aligned with port memory 216. Figure 4B The indicator system 180 can be activated by activating indicator 182. The clinician can then percutaneously insert a needle to access port 200. Figure 4C Advantageously, including indicator system 180 Figures 4A-4C The entry device 150 adds little to no increase in overall size compared to the separate needle and needle bushing assembly. This allows clinicians to access a smaller, lower-profile port without any additional monitors, computing devices, etc., while reducing accidental puncture attempts and keeping their attention focused on the insertion site.

[0049] Figures 5A-5C A floor plan of an implementation scheme for accessing system 100 is shown. (See diagram below.) Figure 5A As shown, the entry device 150 is not aligned with the target window of the diaphragm 216. The sensor 184 cannot detect the port located below it, and the indicator 182 is not activated. Figures 5B-5C As shown, by sliding the device 150 onto the surface of skin 90 towards port 200, sensor 184 can detect when the axis of needle 152 is fully aligned with diaphragm 216 to enter the reservoir below. Sensor 184 can be activated by indicator 182 ( Figure 5C It detects the presence of the subcutaneously placed port 200 and alerts the clinician when the needle is fully aligned with the port storage 216.

[0050] In one implementation, the indicator system 180 may detect the presence of port 200 via one or more modalities. Exemplary modalities may include capacitive, inductive, magnetic, thermal, acoustic, radio frequency (RF), combinations thereof, as described in more detail herein.

[0051] Capacitive mode

[0052] In one embodiment, the indicator system 180 may employ a capacitive mode and includes a capacitive sensor plate 184 and associated circuitry configured to detect changes in the dielectric constant of tissue disposed beneath the bottom surface 172 of the access device 150.

[0053] For example, such as Figure 3A As shown, the capacitance of the skin surface tissue provides a first reading of the dielectric constant. Figure 3B As shown, the capacitance of the subcutaneously arranged port 200 can provide a second dielectric constant reading different from the first dielectric constant reading. The indicator system 180 can detect changes in capacitance of the tissue disposed beneath it and, for example, indicate the alignment of the needle 152 with the port diaphragm 214 and the reservoir 216 by illuminating an LED 182. Figure 3C As shown, the clinician can slide the needle sheath 154 from the retracted position to the extended position to access the port 200. The capacitive modal sensor 184 can extend between 0.15 inches and 3 inches below the skin surface, although larger or smaller ranges are also considered. Advantageously, the capacitive modality of the indicator system 180 can detect the presence of the port 200 without requiring the port 200 to provide any valid or return signal. Thus, the access device 150 can be used with a variety of subcutaneous medical devices that do not require any specific fitting.

[0054] In one embodiment, port 200 or a portion thereof may include a material that provides a different capacitance relative to the surrounding tissue or a different dielectric constant relative to the surrounding material. For example, port body 212 or a portion thereof (e.g., disk 220) may include materials such as platinum, silver, tungsten, gold, cobalt, titanium, silicon dioxide, zirconium oxide, or similar materials that increase the difference in capacitance or dielectric constant relative to the surrounding material. In one embodiment, the material disk 220 may result in an increased density relative to the material forming port 200 or the surrounding tissue. In one embodiment, a portion of the material, such as disk 220, may be positioned below or form the base of the reservoir 216 and may indicate a target window (e.g., target window (x)) of the reservoir 216 (see [link to relevant documentation]). Figures 5A-5C In other words, the diameter of disk 220 can be substantially aligned with the diameter of reservoir 216. The capacitance variation between the surrounding tissue and the port body 212 including disk 220 can clearly indicate the presence of port 200 and improve the alignment of needle 152 with port 200.

[0055] Induction mode

[0056] In one embodiment, the indicator system 180 may include an induction coil 222 disposed within the port body 212. The induction coil 222 can sense a current within a voltmeter sensor 184 disposed within the access device 150, which in turn can illuminate an LED indicator 182. The strength of the induction coil 222 can be configured to sense current within a predetermined range of the port or from a predetermined direction of the port. Exemplary ranges may be between 0.15 inches and 3 inches, although larger or smaller ranges are also considered. Furthermore, the induction coil 222 can be aligned to sense current along an axis extending perpendicular to the skin surface 90. This allows for better sensing when the access device is positioned directly above the port reservoir 216 (e.g., ...). Figure 3B The induction coil 222 can sense the current in the voltmeter sensor 184. When the entry device 150 is not aligned with the port memory, the voltmeter sensor 184 is outside the range of the induction coil 222, there is no induced current and the LED indicator 182 does not light up.

[0057] Advantageously, the LED 182, voltmeter sensor 184, and associated circuitry provide a compact indicator system 180 because the entry device 150 requires no power supply. Instead, power is supplied by an induction coil 222 arranged within the port 200. Thus, the induction indicator system 180 can be included within the entry device 150 with little or no increase in overall size compared to a comparable entry device 150 without the indicator system 180.

[0058] In one embodiment, the voltmeter sensor 184 may include a coil. When the needle 152 is aligned with port 200, an induction coil 222 disposed in port 200 draws voltage from the coil disposed in the voltmeter sensor 184. The voltmeter can then detect the voltage drop in the coil disposed within the voltmeter 184 to confirm that the induction coil 222 is within range, i.e., disposed below the voltmeter sensor 184, such that the axis (a) of the needle 152 is aligned with the port reservoir 216. The indicator system 180 can then alert the user by illuminating an LED, as described herein.

[0059] In one embodiment, the indicator system 180 may include one or more integrated circuits (“ICs”) configured to detect a predetermined voltage setpoint received from sensor 184 and provide a predetermined output to one or more visual, auditory, or tactile indicators (such as LED 182, etc.). For example, as Figures 5A-5CAs shown, system 100 may include circuitry such as a "555" timer configured to detect a first voltage input to indicate a first proximity to port 200 and provide a first output at a first rate for blinking LED 182. As the access device 150 moves closer to port 200, and thus more aligned with memory 216, subsequent voltage readings, such as a second or third voltage reading, can indicate a progressively improving alignment of needle 152 with port memory 216. Thus, the IC or "555" timer can provide a second blinking rate of LED 182 faster than the first rate and a third blinking rate greater than the second rate until needle 152 is aligned with port memory 216.

[0060] In one embodiment, different voltage readings from sensor 184 can be provided by increasing the signal strength detected by sensor 184. In another embodiment, different voltage readings can be provided by different numbers of sensors within sensor array 184, which detects the presence or absence of port 200 disposed below it. For example, as... Figures 5A-5C As shown, two or more sensors of the sensor array 184 can be arranged in a ring around the axis of the needle 152. Figure 5B As shown, when the edge of port 200 is positioned below the first sensor of sensor array 184, a first voltage reading can be provided, indicating that the port is close to but not properly aligned with entry device 150. Figure 5C As shown, when all sensors in the sensor array 184 detect the presence of port 200, a second voltage reading different from the first voltage reading is provided, indicating that port 200 is correctly aligned with needle 152.

[0061] As will be understood, this is exemplary, and the IC or “555” timer may provide other modalities of the indicator system 180, or other indicators such as changes in LED color, audible signals such as signal rate, tone, frequency, amplitude, or the rate, frequency, or amplitude of a vibration signal. These and other configurations of modalities or indicator signals are considered to fall within the scope of this invention.

[0062] Magnetic modes

[0063] In one embodiment, the indicator system 180 may employ a magnetic mode. Port 200 may include a portion, such as a disk 200, comprising an ferromagnetic or magnetic material that provides a passive magnetic field strength. Sensor 184 may include a magnetic or "Hall effect" sensor configured to detect a difference in magnetic field strength between surrounding tissue and port 200, which includes disk 220. When access device 150 is aligned with port 200, the magnetic field strength may indicate when port reservoir 216 is aligned below needle 152, as described herein. The user can then manipulate needle bushing 154 to access port reservoir 216.

[0064] thermal modes

[0065] In one embodiment, the indicator system 180 may employ a thermal mode and includes a thermal sensor 184 and associated circuitry configured to detect temperature changes in tissue disposed below the access device 150. Figure 3A As shown, the temperature of the skin surface tissue provides the initial temperature. Figure 3B As shown, the subcutaneously positioned port 200 can provide a temperature different from the surrounding tissue, for example in Figure 3B The indicator system 180 can detect temperature changes and, for example, indicate the alignment of the needle 152 with the port diaphragm 214 and the reservoir 216 disposed below the port diaphragm 214 by illuminating the LED 182. Figure 3C As shown, the clinician can slide the needle bushing 154 from the retracted position to the extended position to access the port 200. The temperature modal sensor 184 can range from 0.15 inches to 3 inches, although larger or smaller ranges are also considered. Advantageously, the surface contact temperature sensor 184 provides a precise window for temperature detection arranged below the access device 150 to provide accurate alignment of the needle with the port reservoir 216.

[0066] acoustic modes

[0067] In one embodiment, the indicator system 180 may employ an acoustic modality and includes an acoustic transducer and sensor 184, along with associated circuitry, configured to transmit acoustic signals, such as ultrasonic signals, into tissue disposed below the access device 150. Furthermore, the acoustic sensor 184 may detect reflected acoustic signals from the tissue disposed below the access device 150.

[0068] like Figure 3A As shown, transducer sensor 184 can provide an acoustic signal that is directly directed into the tissue directly below the access device 150. The skin surface tissue can provide a first reflected acoustic signal. (As shown...) Figure 3BAs shown, when the entry device 150 is aligned with the port storage 216, the emitted acoustic signal is reflected from the subcutaneously arranged port 200 to provide a second reflected acoustic signal that is different from the first reflected acoustic signal.

[0069] In one embodiment, the first reflected signal may be a signal that is relatively weaker or non-existent compared to the second reflected signal. Thus, due to the presence of the second reflected signal or the increased intensity of the second reflected signal compared to the first reflected signal, the transducer sensor 184 can detect port 200.

[0070] In one embodiment, a first reflected signal can detect a first subcutaneous object, such as bone, at a first distance calculated from the time elapsed between the emitted and reflected signals. A second reflected signal can detect a second subcutaneous object, such as port 200, at a second distance less than the first distance or within a predetermined range. Thus, if the second reflected signal is within the predetermined range, the presence of port 200 is confirmed. In one embodiment, the predetermined range of the acoustic signal can be between 0.15 inches and 3 inches, although larger or smaller ranges are also possible.

[0071] The indicator system 180 can detect reflected acoustic signals and determine the presence of port 200 disposed below it. The indicator system 180 can then alert the user, for example, by illuminating LED 182, that the pin 152 is aligned with port diaphragm 214 and the reservoir 216 disposed below port diaphragm 214. Figure 3C As shown, the clinician can then slide the needle liner 154 from the retracted position to the extended position to access the port 200. In one embodiment, the acoustic modality of the indicator system 180 can detect the presence of the port 200 without requiring the port 200 to provide any valid signal. Thus, the acoustic modality access device 150 can be used with a variety of subcutaneous medical devices that do not require any specific fit.

[0072] In one embodiment, port 200 or a portion thereof may include a material that provides different acoustic reflection properties relative to the surrounding tissue. For example, as described herein, port 200 may include a material disk 220 disposed within port body 212 and below reservoir 216. Variations in acoustic reflection properties between the surrounding tissue and port body 212, including disk 220, can clearly indicate the presence of port 200 and alignment with needle 152. In one embodiment, material disk 220 may have an increased density relative to the material forming port 200 or the surrounding tissue. In one embodiment, disk 220 may include one of platinum, silver, tungsten, gold, cobalt, titanium, silicon dioxide, or zirconium oxide. However, other materials with different acoustic properties are also contemplated.

[0073] RFID mode

[0074] In one embodiment, the indicator system 180 may employ a radio frequency (RF) mode and includes an RFID transmitter and sensor 184 and associated circuitry configured to transmit RF signals to tissue disposed below the access device 150 and detect RFID signals reflected from the tissue disposed below the access device 150.

[0075] like Figure 3A As shown, the RFID transmitter and sensor 184 can provide RF signals directly directed into the tissue directly beneath the access device 150. Without any port 200 and the associated RFID tag 220A disposed below it, no reflected signal is provided, and the indicator needle 152 is not aligned with the port storage 216. Figure 3B As shown, when the entry device 150 is aligned with the port reservoir 216, an RFID signal emitted from sensor 184 is reflected from the RFID tag 220A disposed within the subcutaneously arranged port 200 to provide a distinct reflection response signal. The transducer sensor 184 of the indicator system 180 can detect the reflected response signal and, for example, illuminate LED 182 to indicate that the needle 152 is aligned with the port diaphragm 214 and the reservoir 216 disposed beneath the port diaphragm 214. Figure 3C As shown, the clinician can then slide the needle sheath 154 from the retracted position to the extended position to enter port 200. The RFID signal emitted from the RFID transmitter and sensor 184 has a range of penetrating skin surface tissue to a depth between 0.15 inches and 3 inches. Larger or smaller ranges are also considered.

[0076] Advantageously, the RFID reflected signal can provide a specific response signal from port 200 and mitigate the presence of false positives. This improves the accuracy of detection and alignment of the entry device 150 with the port memory 216 and reduces false spikes. Furthermore, the RFID tag 220A arranged within port 220 does not require any additional power to provide the response signal. Instead, the power to provide the response signal is obtained from the energy emitted by the RFID transmitter sensor 184 of the entry device 150.

[0077] Embodiments of the invention may be embodied in other specific forms without departing from the spirit of this disclosure. The described embodiments are to be considered illustrative in all respects only, and not restrictive. Therefore, the scope of the embodiments is indicated by the appended claims rather than by the foregoing description. All variations within the equivalent meaning and scope of the claims are included within their scope.

Claims

1. An access assembly configured for detecting and accessing a subcutaneous medical device, the access assembly comprising: a needle supported by a needle hub; and an indicator system, the indicator system comprising: a capacitive sensor configured to detect a change in dielectric constant between the subcutaneous medical device and surrounding tissue; and an LED light configured to indicate when the needle is aligned with the subcutaneous medical device.

2. The access assembly of claim 1, further comprising a housing supporting the needle hub and slidably engaged with the needle hub, the needle hub configured to transition between a retracted position and an extended position, the housing defining a bottom surface configured to engage a skin surface, the sensor disposed in the bottom surface.

3. The access assembly of claim 2, wherein the LED light is disposed on one of the housing or the needle hub.

4. The access assembly of any of claims 1-3, wherein the subcutaneous medical device is a port comprising a port body and a septum, the port body and the septum cooperating to define a reservoir, the needle configured to penetrate the septum to access the reservoir beneath the septum when the needle is aligned with the subcutaneous medical device.

5. The access assembly of claim 1, wherein the subcutaneous medical device comprises a disk of material that increases a difference in dielectric constant with the surrounding tissue.

6. The access assembly of claim 5, wherein the disk of material comprises one of platinum, silver, tungsten, gold, cobalt, titanium, silicon dioxide, or zirconium oxide.

7. The access assembly of claim 5 or 6, wherein the subcutaneous medical device is a port comprising a port body and a septum, the port body and the septum cooperating to define a reservoir, the needle configured to penetrate the septum to access the reservoir beneath the septum when the needle is aligned with the subcutaneous medical device, and wherein the disk is disposed beneath the reservoir and defines a diameter that extends the same diameter as the reservoir.

8. The access assembly of claim 2, wherein the sensor is capable of detecting a change in dielectric constant for a depth between 0.15 inches and 3 inches beneath the skin surface.

9. A vascular access system comprising: an access device comprising a needle supported by a needle hub, and comprising a volt meter sensor and an indicator; and a subcutaneous port device comprising a port body defining a reservoir and a needle septum disposed above the port body, the port body comprising an inductive coil configured to induce a current in the volt meter sensor to activate the indicator to provide an alert when an axis of the needle is aligned with the reservoir.

10. The vascular access system of claim 9, wherein the inductive coil is capable of inducing a current along an axis extending perpendicular to a skin surface in a range between 0.15 inches and 3 inches.

11. The vascular access system of claim 9 or 10, wherein the alert is one of a visual, audible, or tactile alert.

12. The vascular access system of claim 9, wherein the indicator is an LED light bulb that is illuminated by current from a voltmeter induced by the inductive coil.

13. The vascular access system of claim 9, further comprising an integrated circuit or "555" timer configured to receive a first voltage from the voltmeter and provide a first output to activate the indicator, and to receive a second voltage from the voltmeter and provide a second output to activate the indicator.

14. An access system configured for detecting alignment with a subcutaneous medical device, the access system comprising: a needle supported by a needle hub; and an indicator system, the indicator system comprising: an acoustic transducer sensor configured to emit an acoustic signal and detect a first reflected signal; and an LED light disposed on the needle hub configured to indicate when an axis of the needle is aligned with the subcutaneous medical device.

15. The access system of claim 14, further comprising a housing supporting the needle hub and slidably engaged with the needle hub, the needle hub configured to transition between a retracted position and an extended position, the housing defining a bottom surface configured to engage a skin surface, the acoustic transducer sensor disposed in the bottom surface.

16. The access system of claim 14 or 15, wherein the subcutaneous medical device is a port comprising a port body and a septum, the port body and the septum cooperating to define a reservoir, the needle configured to penetrate the septum to access the reservoir beneath the septum when the needle is aligned with the subcutaneous medical device.

17. The access system of claim 14, wherein the acoustic signal impinges on the subcutaneous medical device to provide a second reflected signal different from the first reflected signal, the second reflected signal triggering the LED light to emit light.

18. The access system of claim 17, wherein the first reflected signal is relatively weak or non-existent relative to the second reflected signal.

19. The access system of claim 17, wherein the first reflected signal indicates a first distance, and the second reflected signal indicates a second distance different from the first distance, the second distance within a predetermined distance range to indicate presence of the subcutaneous medical device.

20. The access system of any one of claims 17 to 19, wherein the subcutaneous medical device comprises a material disc that increases the difference between the first reflected signal and the second reflected signal.

21. The access system of claim 20, wherein the material disc comprises one of platinum, silver, tungsten, gold, cobalt, titanium, silicon dioxide, or zirconium oxide.

22. The access system of claim 20, wherein the subcutaneous medical device is a port comprising a port body and a septum that cooperate to define a reservoir, the needle is configured to penetrate the septum to access the reservoir beneath the septum when the needle is aligned with the subcutaneous medical device, and wherein the disc is disposed beneath the reservoir and defines a diameter that extends the same diameter as the reservoir.

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