US20060282290A1 - Components and Methods For Patient Infusion Device - Google Patents

Abstract

A fluid delivery device including a housing, a reservoir positioned within the housing, and a transcutaneous access tool positioned within the housing and including, a cannula in fluid communication with the reservoir and linearly moveable along an axis of the transcutaneous access tool through a port in a wall of the housing, a deployment member secured to the cannula and movable along the axis of the transcutaneous access tool against the wall of the housing defining the port, and an annular seal coaxially positioned about the cannula and positioned between the deployment member and the wall of the housing defining the port, so that the seal provides a substantially fluid-tight seal between the deployment member and the wall of the housing when the deployment member is moved against the wall of the housing.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS
• The present application is a divisional of U.S. patent application Ser. No. 10/260,192, which is related to U.S. Pat. No. 6,740,059 entitled DEVICES, SYSTEMS AND METHODS FOR PATIENT INFUSION, which is assigned to the assignee of the present application and incorporated herein by reference.
FIELD OF THE INVENTION
• The present invention relates generally to medical devices, systems and methods, and more particularly to small, low cost, portable infusion devices and methods that are useable to achieve precise, sophisticated, and programmable flow patterns for the delivery of therapeutic liquids such as insulin to a mammalian patient. Even more particularly, the present invention is directed to various new and improved components and methods for an infusion device.
BACKGROUND OF THE INVENTION
• Today, there are numerous diseases and other physical ailments that are treated by various medicines including pharmaceuticals, nutritional formulas, biologically derived or active agents, hormonal and gene based material and other substances in both solid or liquid form. In the delivery of these medicines, it is often desirable to bypass the digestive system of a mammalian patient to avoid degradation of the active ingredients caused by the catalytic enzymes in the digestive tract and liver. Delivery of a medicine other than by way of the intestines is known as parenteral delivery. Parenteral delivery of various drugs in liquid form is often desired to enhance the effect of the substance being delivered, insuring that the unaltered medicine reaches its intended site at a significant concentration. Also, undesired side effects associated with other routes of delivery, such as systemic toxicity, can potentially be avoided.
• Often, a medicine may only be available in a liquid form, or the liquid version may have desirable characteristics that cannot be achieved with solid or pill form. Delivery of liquid medicines may best be accomplished by infusing directly into the cardiovascular system via veins or arteries, into the subcutaneous tissue or directly into organs, tumors, cavities, bones or other site specific locations within the body.
• Parenteral delivery of liquid medicines into the body is often accomplished by administering bolus injections using a needle and reservoir, or continuously by gravity driven dispensers or transdermal patch technologies. Bolus injections often imperfectly match the clinical needs of the patient, and usually require larger individual doses than are desired at the specific time they are given. Continuous delivery of medicine through gravity feed systems compromise the patient's mobility and lifestyle, and limit the therapy to simplistic flow rates and profiles. Transdermal patches have special requirements of the medicine being delivered, particularly as it relates to the molecular structure, and similar to gravity feed systems, the control of the drug administration is severely limited.
• Ambulatory infusion pumps have been developed for delivering liquid medicaments to a patient. These infusion devices have the ability to offer sophisticated fluid delivery profiles accomplishing bolus requirements, continuous infusion and variable flow rate delivery. These infusion capabilities usually result in better efficacy of the drug and therapy and less toxicity to the patient's system. An example of a use of an ambulatory infusion pump is for the delivery of insulin for the treatment of diabetes mellitus. These pumps can deliver insulin on a continuous basal basis as well as a bolus basis as is disclosed in U.S. Pat. No. 4,498,843 to Schneider et al.
• The ambulatory pumps often work with a reservoir to contain the liquid medicine, such as a cartridge, a syringe or an IV bag, and use electromechanical pumping or metering technology to deliver the medication to the patient via tubing from the infusion device to a needle that is inserted transcutaneously, or through the skin of the patient. The devices allow control and programming via electromechanical buttons or switches located on the housing of the device, and accessed by the patient or clinician. The devices include visual feedback via text or graphic screens, such as liquid crystal displays known as LCD's, and may include alert or warning lights and audio or vibration signals and alarms. The device can be worn in a harness or pocket or strapped to the body of the patient.
• Currently available ambulatory infusion devices are expensive, difficult to program and prepare for infusion, and tend to be bulky, heavy and very fragile. Filling these devices can be difficult and require the patient to carry both the intended medication as well as filling accessories. The devices require specialized care, maintenance, and cleaning to assure proper functionality and safety for their intended long term use. Due to the high cost of existing devices, healthcare providers limit the patient populations approved to use the devices and therapies for which the devices can be used.
• Clearly, therefore, there was a need for a programmable and adjustable infusion system that is precise and reliable and can offer clinicians and patients a small, low cost, light-weight, easy-to-use alternative for parenteral delivery of liquid medicines.
• In response, the applicant of the present application provided a small, low cost, light-weight, easy-to-use device for delivering liquid medicines to a patient. The device, which is described in detail in co-pending U.S. application Ser. No. 09/943,992, filed on Aug. 31, 2001, includes an exit port, a dispenser for causing fluid from a reservoir to flow to the exit port, a local processor programmed to cause a flow of fluid to the exit port based on flow instructions from a separate, remote control device, and a wireless receiver connected to the local processor for receiving the flow instructions. To reduce the size, complexity and costs of the device, the device is provided with a housing that is free of user input components, such as a keypad, for providing flow instructions to the local processor. What is still desired, however, are additional new and improved components and methods for devices for delivering fluid to a patient.
SUMMARY OF THE INVENTION
• The present invention provides a transcutaneous access tool for use as part of device for delivering fluid, such as insulin for example, to a patient. The transcutaneous access tool includes a first cannula moveable along an axis of the transcutaneous access tool, a fixed member including an elongated prong extending parallel with the axis, and a deployment member secured to the first cannula. The deployment member is movable along the axis away from the fixed member and includes spaced-apart, resiliently flexible fingers extending parallel with the axis and slidingly received on the prong of the fixed member. The fingers having distal ends that are laterally enlarged with respect to the axis.
• The transcutaneous access tool also includes a second cannula disposed within the lumen of the first cannula, and a retraction member secured to the second cannula and movable along the axis between the fixed member and the deployment member. The retraction member includes at least one catch extending laterally inwardly with respect to the axis. The catch catches on the laterally enlarged distal ends of the fingers of the deployment element, and prevents the retraction member from being moved away from the deployment member, when the fingers are laterally held apart by the prong of the fixed member.
• According to one aspect of the present invention, the transcutaneous access tool further includes a deployment spring biasing the deployment member away from the fixed member, and a retraction spring biasing the retraction member away from the deployment member and towards the fixed member. According to another aspect, the first cannula is flexible and the second cannula is rigid.
• The present invention also provides a fluid delivery device including a housing, a reservoir positioned within the housing, and a transcutaneous access tool positioned within the housing. The transcutaneous access tool includes a cannula in fluid communication with the reservoir and linearly moveable along an axis of the transcutaneous access tool through a port in a wall of the housing, a deployment member secured to the cannula and movable along the axis of the transcutaneous access tool against the wall of the housing defining the port, and an annular seal coaxially positioned about the cannula and positioned between the deployment member and the wall of the housing defining the port, so that the seal provides a substantially fluid-tight seal between the deployment member and the wall of the housing when the deployment member is moved against the wall of the housing. The seal allows a fluid or gas, such as a sterilization medium, to enter the exit port from outside the housing prior to deployment of the cannula, but seals the housing in a fluid-tight manner upon deployment of the cannula.
• According to one aspect of the present invention, the device also includes an outlet plug removably connected to a distal end of the cannula extending out of the housing, and the port in the wall of the housing comprises an internal exit port and the housing further includes an external exit port for the flexible cannula and a sterilization access port adjacent the external exit port.
• The present invention additionally provides a fluid delivery device including a housing having a port providing communication with an interior of the device, an adhesive layer provided on an exterior surface of the housing surrounding the port of the housing and including resilient flaps normally sealing the port in a substantially fluid-tight manner, and a protective layer removably covering the adhesive layer and including a sterilization access tube extending through the flaps of the adhesive layer and into the housing. The sterilization access tube allows a fluid or gas, such as a sterilization medium, to enter the port from outside the housing prior to removal of the protective layer, and the flaps seal the port in a fluid-tight manner after removal of the protective layer.
• The present invention also provides a flow path assembly including a base layer having opposing first and second surfaces. The base layer defines a fill chamber outlet port extending through the base layer and between the opposing first and second surfaces, an auxiliary chamber inlet port extending through the base layer and between the opposing first and second surfaces, and a first groove on the second surface of the base layer connecting the fill chamber outlet port to the auxiliary chamber inlet port. The base layer also defines an auxiliary chamber outlet port extending through the base layer and between the opposing first and second surfaces, a reservoir inlet port extending through the base layer and between the opposing first and second surfaces, and a second groove on the second surface of the base layer connecting the auxiliary chamber outlet port to the reservoir inlet port. The base layer further defines a reservoir outlet port extending through the base layer and between the opposing first and second surfaces, a cannula inlet port extending through the base layer and between the opposing first and second surfaces, and a third groove on the second surface of the base layer connecting the reservoir outlet port to the cannula inlet port. The flow path assembly also includes a cover layer substantially covering the second surface of the base layer in a substantially fluid-tight manner.
• According to one aspect of the present invention, the base layer is relatively rigid and the cover layer is relatively flexible. According to another aspect, the flow path assembly includes a cannula connector member secured to the first surface of the base layer in a substantially fluid-tight manner and defining a cannula connector chamber in fluid communication with the cannula inlet port of the base layer. According to an additional aspect, the flow path assembly includes a fill port member secured to the first surface of the base layer in a substantially fluid-tight manner and defining a fill port chamber in fluid communication with the fill chamber outlet port of the base layer.
• According to another aspect of the present invention, the first surface of the base layer defines an auxiliary recess connecting the auxiliary chamber inlet port and the auxiliary chamber outlet port. According to a further aspect, the assembly includes a sensor assembly secured to the auxiliary chamber recess of the first surface of the base layer in a substantially fluid-tight manner, and the sensor assembly has a sensor chamber in fluid communication with the auxiliary chamber inlet port and the auxiliary chamber outlet port of the base layer.
• According to an additional aspect, the first surface of the base layer defines a reservoir shelf connecting the reservoir inlet port and the reservoir outlet port. According to another aspect, the assembly further includes a reservoir secured to the reservoir shelf of the first surface of the base layer in a substantially fluid-tight manner and the reservoir has a reservoir chamber in fluid communication with the reservoir inlet port and the reservoir outlet port. According to yet another aspect, the reservoir includes an end cap closing the open first end of cylindrical side wall in a substantially fluid-tight manner and defining a reservoir port providing fluid communication between the reservoir chamber and the reservoir inlet port and the reservoir outlet port.
• The present invention provides another flow path assembly including a cylindrical side wall having opposing first and second open ends and defining a reservoir chamber, an end cap closing the second open end of the side wall and defining a port providing fluid communication with the reservoir chamber, a plunger received in the reservoir chamber and slidingly moveable along the side wall and between the opposing first and second open ends, and a lead screw extending into the first open end of the side wall and having a distal end secured to the plunger.
• According to one aspect of the present invention, the flow path assembly further includes a base layer having opposing first and second surfaces, a fill chamber outlet port extending through the base layer and between the opposing first and second surfaces, a reservoir inlet port extending through the base layer and between the opposing first and second surfaces, a reservoir outlet port extending through the base layer and between the opposing first and second surfaces, and a cannula inlet port extending through the base layer and between the opposing first and second surfaces. The second surface of the base layer defines a first groove connecting the fill chamber outlet port to the reservoir inlet port, and a second groove connecting the reservoir outlet port to the cannula inlet port. The first surface of the base layer defines a reservoir recess connecting the reservoir inlet port and the reservoir outlet port and receiving the end cap of the reservoir in a substantially fluid-tight manner. The port of the end cap provides fluid communication between the reservoir chamber and the reservoir inlet port and the reservoir outlet port.
• The present invention provides an additional flow path assembly including a first portion and a second portion of a housing of a fluid delivery device assembled together to form an end wall of the housing. The end wall includes a fill port, a reservoir connection port, a cannula connection port, and at least one flow path connecting the fill port, the reservoir connection port and the cannula connection port.
• According to one aspect of the present invention, the first portion of the housing includes a first portion of the end wall and the second portion of the housing includes a second portion of the end wall. The first and the second portions of the end wall have mating surfaces defining corresponding grooves which together define the flow path of the end wall when the first and the second portions of the housing are assembled together.
• These aspects of the invention together with additional features and advantages thereof may best be understood by reference to the following detailed descriptions and examples taken in connection with the accompanying illustrated drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is a perspective view of a first exemplary embodiment of a fluid delivery device constructed in accordance with the present invention shown secured on a patient, and a remote control device for use with the fluid delivery device (the remote control device being enlarged with respect to the patient and the fluid delivery device for purposes of illustration);
• FIGS. 2aand2bare enlarged top and bottom perspective views, respectively, of the fluid delivery device ofFIG. 1;
• FIG. 3 is a further enlarged top perspective view of the fluid delivery device ofFIG. 1, shown with a top housing portion removed to reveal interior portions of the fluid delivery device, including an exemplary embodiment of a transcutaneous access tool constructed in accordance with the present invention and an exemplary embodiment of a laminated flow path constructed in accordance with the present invention;
• FIGS. 4a-4care simplified schematic views of the transcutaneous access tool of the fluid delivery device ofFIG. 3 illustrating deployment of a needle of the tool;
• FIG. 5 is a further enlarged end perspective view of the transcutaneous access tool ofFIG. 3 showing an exemplary embodiment of an exit port seal constructed in accordance with the present invention for sealing the exit port of the device housing upon deployment of the needle of the deployment of a needle of the tool;
• FIG. 6 is a sectional view of a fluid delivery device including an exemplary embodiment of a exit port seal assembly constructed in accordance with the present invention;
• FIG. 7 is an enlarged sectional view of a portion of the exemplary embodiment of the exit port seal assembly contained incircle7 ofFIG. 6, illustrating how the assembly allows an interior of the device to be sterilized prior to use of the device;
• FIG. 8 is a sectional view of the fluid delivery device ofFIG. 6 showing a protective bottom layer of the exit port seal assembly removed;
• FIG. 9 is an enlarged sectional view of a portion of the exemplary embodiment of the exit port seal assembly contained incircle9 ofFIG. 8, illustrating how the assembly seals the interior of the device upon removal of the protective bottom layer and prior to use of the device;
• FIG. 10 is an enlarged sectional view of an exemplary embodiment of an outlet plug constructed in accordance with the present invention shown positioned within an outlet port of a housing a fluid delivery device, and wherein the housing includes a sterilization access port adjacent the outlet port;
• FIG. 11 is an enlarged end perspective view of a portion of the laminated flow path assembly of the fluid delivery device ofFIG. 3;
• FIG. 12 is an enlarged sectional view of an exemplary embodiment of a fluid reservoir and a reservoir end wall constructed in accordance with the present invention, and an exemplary embodiment of a plunger and a lead screw constructed in accordance with the present invention and received in the reservoir for forcing fluid towards the end wall;
• FIG. 13 is a first end view of the plunger ofFIG. 12;
• FIG. 14 is a second end view of a portion of an exemplary embodiment of a laminated flow path constructed in accordance with the present invention for attachment to the end wall of the reservoir ofFIG. 12;
• FIG. 15 is a sectional view of an exemplary embodiment of a fluid reservoir constructed in accordance with the present invention, and an exemplary embodiment of a device housing including a laminated flow path constructed in accordance with the present invention; and
• FIG. 16 is a sectional view taken along line16-16 ofFIG. 15 of the device housing showing the laminated flow path connected to the reservoir.
• Like reference characters designate identical or corresponding components and units throughout the several views.
DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
• Referring toFIGS. 1 through 3, there is illustrated an exemplary embodiment of afluid delivery device10 constructed in accordance with the present inventions. Referring toFIG. 3, thefluid delivery device10 includes exemplary embodiments of areservoir12 for receiving and holding fluid to be delivered by thedevice10, atranscutaneous access tool14 for providing fluid communication between thereservoir12 and a patient, and a laminatedflow path assembly16 connecting afill port18 to thereservoir12 and the reservoir to thetranscutaneous access tool14, all constructed in accordance with the present inventions.
• Thefluid delivery device10 can be used for the delivery of fluids to a person or animal. The types of liquids that can be delivered by thefluid delivery device10 include, but are not limited to, insulin, antibiotics, nutritional fluids, total parenteral nutrition or TPN, analgesics, morphine, hormones or hormonal drugs, gene therapy drugs, anticoagulants, analgesics, cardiovascular medications, AZT or chemotherapeutics. The types of medical conditions that thefluid delivery device10 might be used to treat include, but are not limited to, diabetes, cardiovascular disease, pain, chronic pain, cancer, AIDS, neurological diseases, Alzheimer's Disease, ALS, Hepatitis, Parkinson's Disease or spasticity. The volume of thereservoir12 is chosen to best suit the therapeutic application of thefluid delivery device10 impacted by such factors as available concentrations of medicinal fluids to be delivered, acceptable times between refills or disposal of thefluid delivery device10, size constraints and other factors.
• Thefluid delivery device10 also includes adispenser20 for causing fluid from thereservoir12 to flow to thetranscutaneous access tool14. A processor or electronic microcontroller (hereinafter referred to as the “local” processor)22 is connected to thedispenser20, and is programmed to cause a flow of fluid to thetranscutaneous access tool14 based on flow instructions from a separate,remote control device1000, an example of which is shown inFIG. 1. Awireless receiver24 is connected to thelocal processor22 for receiving flow instructions from theremote control device1000 and delivering the flow instructions to thelocal processor22. Thedevice10 also includes ahousing26 containing theflow path assembly16, thetranscutaneous access tool14, thereservoir12, thedispenser20, thelocal processor22, and thewireless receiver24.
• As shown best inFIGS. 2aand2b, thehousing26 of thefluid delivery device10 is free of user input components for providing flow instructions to the local processor, such as electromechanical switches or buttons on an outer surface of thehousing26, or interfaces otherwise accessible to a user to adjust the programmed flow rate through the local processor. The lack of user input components allows the size, complexity and costs of thedevice10 to be substantially reduced so that thedevice10 lends itself to being small and disposable in nature. Examples of such devices are disclosed in co-pending U.S. patent application Ser. No. 09/943,992, filed on Aug. 31, 2001 (Atty. Docket No. INSL-110), and entitled DEVICES, SYSTEMS AND METHODS FOR PATIENT INFUSION, which is assigned to the assignee of the present application and has previously been incorporated herein by reference.
• In order to program, adjust the programming of, or otherwise communicate user inputs to the local processor, thefluid delivery device10 includes the wireless communication element, orreceiver24, as shown inFIG. 3, for receiving the user inputs from the separate,remote control device1000 ofFIG. 1. Signals can be sent via a communication element (not shown) of theremote control device1000, which can include or be connected to anantenna1300, shown inFIG. 1 as being external to thedevice1000.
• Theremote control device1000 has user input components, including an array of electromechanical switches, such as themembrane keypad1200 shown. Theremote control device1000 also includes user output components, including a visual display, such as a liquid crystal display (LCD)1100. Alternatively, thecontrol device1000 can be provided with a touch screen for both user input and output. Although not shown inFIG. 1, theremote control device1000 has its own processor (hereinafter referred to as the “remote” processor) connected to themembrane keypad1200 and theLCD1100. The remote processor receives the user inputs from themembrane keypad1200 and provides “flow” instructions for transmission to thefluid delivery device10, and provides information to theLCD1100. Since theremote control device1000 also includes avisual display1100, thefluid delivery device10 can be void of an information screen, further reducing the size, complexity and costs of thedevice10.
• Thecommunication element24 of thedevice10 preferably receives electronic communication from theremote control device1000 using radio frequency or other wireless communication standards and protocols. In a preferred embodiment, thecommunication element24 is a two-way communication element, including a receiver and a transmitter, for allowing thefluid delivery device10 to send information back to theremote control device1000. In such an embodiment, theremote control device1000 also includes an integral communication element comprising a receiver and a transmitter, for allowing theremote control device1000 to receive the information sent by thefluid delivery device10.
• Thelocal processor22 of thedevice10 contains all the computer programs and electronic circuitry needed to allow a user to program the desired flow patterns and adjust the program as necessary. Such circuitry can include one or more microprocessors, digital and analog integrated circuits, resistors, capacitors, transistors and other semiconductors and other electronic components known to those skilled in the art. Thelocal processor22 also includes programming, electronic circuitry and memory to properly activate thedispenser20 at the needed time intervals.
• In the exemplary embodiment ofFIG. 3, thedevice10 also includes apower supply28, such as a battery or capacitor, for supplying power to thelocal processor22. The power supply is preferably integrated into thefluid delivery device10, but can be provided as replaceable, e.g., a replaceable battery. Thedevice10 can also include sensors or transducers such as a flowcondition sensor assembly30 or dispenser position monitors32, for transmitting information to thelocal processor22 to indicate how and when to activate thedispenser20, or to indicate other parameters determining fluid flow, as well as conditions such as the reservoir being empty or leaking, or the dispensing of too much or too little fluid from thereservoir12, etc.
• As shown inFIG. 2b, thedevice10 can also be provided with anadhesive layer34 on the outer surface of thehousing26 for securing thedevice10 directly to the skin of a patient, as illustrated inFIG. 1. Theadhesive layer34 is provided on an external “bottom” surface of thehousing26. Theadhesive layer34 is also preferably provided in a continuous ring encircling anexternal exit port36 of thehousing26 in order to provide a protective seal around the penetrated patient's skin to prevent the penetrated skin from becoming contaminated when acannula38 of thetranscutaneous access tool14 extends through the skin. It is preferable that thefill port18 extend through the bottom surface of thehousing26 to discourage and prevent filling and re-filling of thefluid delivery device10 when thedevice10 is attached to a patient's skin. Thehousing26 can be made from flexible material, or can be provided with flexible hinged sections that allow thefluid delivery device10 to flex during patient movement to prevent detachment and aid in patient comfort.
• As shown inFIGS. 2band3, anoutlet plug40 is secured to the distal end of thecannula38 of thetranscutaneous access tool14 prior to use of thedevice10. Theoutlet plug40 has an air removal filter that allows air but not fluid to exit thecannula38, and acts as a flow restriction system that operates to substantially prime (i.e., purge of air) the flow path of thefluid delivery device10 prior to operation of thedevice10, to ensure that a desired volume of fluid is accurately delivered by thedevice10 during operation.
• In the exemplary embodiment ofFIG. 3, thereservoir12 is not pressurized, and thedispenser20 is adapted to control flow from thereservoir12 by driving or pumping the fluid from the reservoir to thetranscutaneous access tool14. Examples of such “driving or pumping” dispensers are shown in co-pending U.S. patent application Ser. No. 09/955,623, filed on Sep. 19, 2001 (Atty. Docket No. INSL-117), and entitled PLUNGER FOR PATIENT INFUSION DEVICE, which is assigned to the assignee of the present application and incorporated herein by reference. Other examples of dispensers are shown in co-pending U.S. patent application Ser. No. 10/128,205, filed on Apr. 23, 2002 (Atty. Docket No. INSL-122), and entitled DISPENSER FOR PATIENT INFUSION DEVICE, which is assigned to the assignee of the present application and incorporated herein by reference, and co-pending U.S. patent application Ser. No. 10/128,203, filed on Apr. 23, 2002 (Atty. Docket No. INSL-123), and entitled DISPENSER FOR PATIENT INFUSION DEVICE, which is assigned to the assignee of the present application and incorporated herein by reference. Further examples of dispensers are shown in co-pending U.S. patent application Ser. No. 10/163,688, filed on Jun. 9, 2002 (Atty. Docket No. INSL-124), and entitled PLUNGER FOR PATIENT INFUSION DEVICE, which is assigned to the assignee of the present application and incorporated herein by reference, and in co-pending U.S. patent application Ser. No. 10/163,690, filed on Jun. 9, 2002 (Atty. Docket No. INSL-125), and entitled PLUNGER FOR PATIENT INFUSION DEVICE, which is also assigned to the assignee of the present application and incorporated herein by reference.
• In the embodiment shown inFIGS. 4 and 5, thereservoir12 includes acylindrical side wall42 extending towards anoutlet44 connected to thetranscutaneous access tool14. A threadedlead screw46 is received in thereservoir12 and extends towards theoutlet44 of thereservoir12 generally parallel with theside wall42 of thereservoir12, and aplunger48 is secured to an end of thelead screw46. Thelead screw46, theplunger48 and thereservoir12 are adapted (e.g., provided with o-rings) such that a fluid-tight seal is formed between theplunger48 and thelead screw46 and a fluid-tight seal is formed between theplunger48 and the side wall of thereservoir12, so that movement of theplunger48 towards theoutlet44 of thereservoir12 forces fluid through theoutlet44 to thetranscutaneous access tool14.
• Thedispenser20 causes fluid flow by causing linear movement of thelead screw46 and theplunger48 towards theoutlet44 of thereservoir12. Although not shown inFIG. 3, thedispenser20 includes an elongated shape memory element connected to thelocal processor22 and having a changeable length decreasing from an uncharged length to a charged length when at least one charge is applied to the shape memory element. The shape memory element is operatively connected to theplunger48 such that the changeable length of the shape memory element causes theplunger48 to move along theside wall42 of thereservoir12.
• In the exemplary embodiment shown inFIG. 3, thedispenser20 includes arotatable gear50 linearly fixed with respect to thereservoir12. Thegear50 is coaxially fixed to an exterior surface of a slottedtube52 such that rotation of thegear50 causes rotation of the slottedtube52 about a common longitudinal axis “A”. Thelead screw46 is coaxially positioned within the slottedtube52 and includes aradially extending pin54 slidingly received in longitudinal slots of the slottedtube52 such that rotation of the slottedtube52 causes rotation of thelead screw46. Thelead screw46 is also threadedly engaged with a fixednut assembly56, such that rotation of thegear50 causes linear movement of thelead screw46 through the fixednut assembly56 and linear movement of theplunger48 towards theoutlet44 of thereservoir12. In one exemplary embodiment, the fixednut assembly56 is configured to be disengaged from thelead screw46 prior to use of the device to allow thelead screw46 and theplunger48 to be linearly moved away from aninlet58 of thereservoir12 during filling of thereservoir12 through thefill port18.
• Thedispenser20 further includes aratchet member60 for engaging radially extending teeth of thegear50, wherein theratchet member60 and thegear50 are adapted such that linear movement of theratchet member60 in a first direction adjacent thegear50 causes rotation of thegear50, while linear movement of theratchet member60 in a second direction adjacent thegear50 causes no rotation of thegear50. The elongated shape memory element (not viewable) is connected to theratchet member60 such that the changeable length of the shape memory element decreasing from an uncharged length to a charged length causes linear movement of theratchet member60 in one of the first and the second directions. Thedispenser20 can also include a return element, such as a hinge spring (not viewable), connected to theratchet member60 for causing linear movement of theratchet member60 in the first direction.
• It should be understood, however, that other types of dispensers can also be used with a device incorporating thereservoir12, thetranscutaneous access tool14, or the laminatedflow path assembly16 of the present inventions. For example, thereservoir12 can be pressurized and a dispenser that does not create a driving or pumping force, but rather acts as a metering device, allowing pulses of fluid to pass from thepressurized reservoir12, through the dispenser, to thetranscutaneous access tool14. Examples of such “metering” dispensers are shown in co-pending U.S. patent application Ser. No. 09/977,434, filed Oct. 12, 2001 (Atty. Docket No. INSL-116), and entitled LAMINATED PATIENT INFUSION DEVICE, which is assigned to the assignee of the present application and incorporated herein by reference. In any event, in the exemplary embodiment shown the dispenser is controlled by thelocal processor22, which includes electronic programming, controls, and circuitry to allow sophisticated fluid delivery programming and control of the dispenser.
• Referring now toFIGS. 3 through 5, the exemplary embodiment of thetranscutaneous access tool14 constructed in accordance with the present invention includes thefirst cannula38, which is preferably flexible, and a rigidsecond cannula62 disposed within the lumen of the flexiblefirst cannula38. Thetranscutaneous access tool14 also includes amovable deployment member64 secured to thefirst cannula38, amovable retraction member66 secured to thesecond cannula62, and a stationary fixedmember68 secured to thehousing26.
• Thetranscutaneous access tool14 further includes alatch72 that normally maintains thedeployment member64 and thefirst cannula38 in a pre-deployment position against the bias force of a compressedhelical deployment spring70. Ashape memory element74 activated upon the application of an electrical charge removes thelatch72 from the travel path of thedeployment member64, thereby allowing thedeployment spring70 to drive thedeployment member64 and theretraction member66 away from the fixedmember68 and toward aninternal exit port76 of awall78 of thehousing26, and force the distal tips of both thefirst cannula38 and thesecond cannula62 through theexternal exit port36 and into the skin of the patient.FIG. 4ashows thetranscutaneous access tool14 prior to deployment, whileFIG. 4bshows thetranscutaneous access tool14 after deployment with thedeployment member64 and theretraction member66 moved fully away from the fixedmember68 by thedeployment spring70.
• Thetranscutaneous access tool14 is in fluid communication with thereservoir12 of thedevice10 at all times before and after injection of thefirst cannula38 into the skin of the patient. Thehousing26 includes acannula guide portion80 which deflects the cannula (e.g., by approximately 40°) as thecannula38 passes between theinternal exit port76 and theexternal exit port36. However, thecannula38 does not have a bent distal end (e.g., bent approximately 90°).
• A compressedhelical retraction spring82 biases theretraction member66 away from thedeployment member64. After thesecond cannula62 has injected the distal tip of thefirst cannula38 into the skin of the patient, theretraction spring82 is allowed to force theretraction member66 away from thedeployment member64 and towards the fixedmember68, and withdraw thesecond cannula62 from the skin of the patient, as shown inFIG. 4c. Thedeployment member64, however, maintains thefirst cannula38 in the skin of the patient such that a relatively comfortable flow path is created between thereservoir12 and the patient.
• In the exemplary embodiment ofFIGS. 3 through 5, thetranscutaneous access tool14 includes anelongated prong84 extending from the fixedmember68 parallel with an axis “B” of thetranscutaneous access tool14, spaced-apart, resilientlyflexible fingers86 extending from thedeployment member64 parallel with the axis “B” and slidingly received on theprong84 of the fixedmember68, and acatch88 of theretraction member66 extending laterally inwardly with respect to the axis “B”. Thecatch88 catches on laterally enlarged distal ends90 of thefingers86 of thedeployment member64, and prevents theretraction member66 from being moved away from thedeployment member64 when thefingers86 are laterally held apart by theprong84 of the fixedmember68, as shown inFIGS. 4aand4b.
• Theprong84 and thefingers86, however, are sized so that thefingers86 slide off a distal end of theprong84 when thedeployment member64 is fully deployed by thedeployment spring70, as shown inFIG. 4c. The force of theretraction spring82 causes thecatch88 of theretraction member66 to force the laterally enlarged distal ends90 of thefingers86 laterally together (i.e., squeeze thefingers86 together) and be released from the laterally enlarged distal ends90. Theretraction spring82 then forces theretraction member66 away from thedeployment member64 and towards the fixedmember68, and withdraws thesecond cannula62 from the skin of the patient, as shown inFIG. 4c.
• Referring toFIGS. 3 through 5, thetrancutaneous access tool14 also includes anseal92 that is moved between thedeployment member64 and thewall78 of thehousing26 defining theinternal exit port76 upon deployment of thecannula38. Theseal92 provides a substantially fluid-tight seal between thedeployment member64 and thewall78 of thehousing26 when thedeployment member64 is moved against thewall78, as shown inFIG. 4c. Theseal92 allows a fluid or gas, such as a sterilization medium (e.g., ethylene oxide), to enter theinternal exit port76 from outside thehousing26 prior to deployment of thecannula38, but seals thehousing26 in a fluid-tight manner upon deployment of thecannula38.
• In the exemplary embodiment shown, theseal92 is annular in shape, is coaxially positioned about thefirst cannula38, and is secured to thedeployment member64. Theseal92 is made from a resiliently flexible material such as an elastomer or rubber. Theseal92 can also be bonded to an outer surface of thefirst cannula38.
• Referring toFIG. 10, if theoutlet plug40, which includes aside collar portion94 and a centralair filter portion96, is connected to the distal end of thecannula38 prior to use of thefluid delivery device10, thehousing26 can further be provided with asterilization access port98 adjacent theexternal exit port36. As its name implies, thesterilization access port98 allows a sterilization medium to enter thehousing26 when theoutlet plug40 is blocking theexternal exit port36. Alternatively, theoutlet plug40 can be provided with its own sterilization access port, which would be formed in theside collar portion94 of the outlet plug.
• Referring now toFIGS. 3 and 11, the exemplary embodiment of theflow path assembly16 includes abase layer100 having opposing first andsecond surfaces102,104. Thebase layer100 defines a fillchamber outlet port106 extending through thebase layer100 and between the opposing first andsecond surfaces102,104, an auxiliarychamber inlet port108 extending through thebase layer100 and between the opposing first andsecond surfaces102,104, and afirst groove110 on thesecond surface104 of thebase layer100 connecting the fillchamber outlet port106 to the auxiliarychamber inlet port108. Thebase layer100 also defines an auxiliarychamber outlet port112 extending through thebase layer100 and between the opposing first and second surfaces, thereservoir inlet port58 extending through thebase layer100 and between the opposing first and second surfaces, and asecond groove114 on thesecond surface104 of thebase layer100 connecting the auxiliarychamber outlet port112 to thereservoir inlet port58. Thebase layer100 further defines thereservoir outlet port44 extending through thebase layer100 and between the opposing first and second surfaces, acannula inlet port116 extending through thebase layer100 and between the opposing first and second surfaces, and athird groove118 on thesecond surface104 of thebase layer100 connecting thereservoir outlet port44 to thecannula inlet port116.
• As shown inFIG. 3, theflow path assembly16 also includes acover layer118 substantially covering thesecond surface104 of thebase layer100 in a substantially fluid-tight manner, such that thegrooves110,114,118 in thesecond surface104 of thebase layer100 are formed into fluid passageways. Preferably, thebase layer100 is relatively rigid and thecover layer118 is relatively flexible. Thebase layer100 is preferably comprised of a relatively rigid plastic that is formed through injection molding, for example, while thecover layer118 is made from a relatively flexible fluid-tight plastic, such as an elastomer, rubber or thermoplastic. Thebase layer100 and thecover layer118 are secured together in a suitable manner through bonding or by using an adhesive, for example, in order to seal thegrooves110,114,118 of thebase layer100 in a fluid-tight manner. Among other benefits and features, the laminated construction of theflow path assembly16 simplifies manufacturing (and thus the cost) of the resultingfluid delivery device10.
• Referring toFIGS. 3 and 11, theflow path assembly16 also includes acannula connector member120 secured to thefirst surface102 of thebase layer100 in a substantially fluid-tight manner and defining a cannula connector chamber (not viewable) in fluid communication with thecannula inlet port116 of thebase layer100. Theconnector member120 includes aneedle septum122 fitted in an opening of the connector chamber. Thesecond cannula62 of thetranscutaneous access tool14 extends through theneedle septum122 to provide fluid communication between thereservoir12 and thefirst cannula38. Preferably, theconnector member120 is unitarily formed as a single piece with thebase layer100, by injection molding for example.
• Still referring toFIGS. 3 and 11, theflow path assembly16 also includes thefill port18 secured to thefirst surface102 of thebase layer100 in a substantially fluid-tight manner and defining a fill port chamber (not viewable) in fluid communication with the fillchamber outlet port106 of thebase layer100. Thefill port18 includes a needle septum124 (as shown inFIG. 2b) fitted in an opening of the fill port chamber. Preferably, thefill port18 is unitarily formed as a single piece with thebase layer100, by injection molding for example.
• Although not viewable, thefirst surface102 of thebase layer100 defines an auxiliary recess connecting the auxiliarychamber inlet port108 and the auxiliarychamber outlet port112. Theflow sensor assembly30 is secured to the auxiliary recess of thefirst surface102 of thebase layer100 in a substantially fluid-tight manner, and theflow sensor assembly30 has a flow sensor chamber (not viewable) in fluid communication with the auxiliarychamber inlet port108 and the auxiliarychamber outlet port112 of thebase layer100. The flow sensor assembly provides an indication of fluid pressure within theflow path assembly16, so that conditions within the flow path assembly can be determined. Examples of flow sensor assemblies are shown in co-pending U.S. patent application Ser. No. 10/087,507, filed on Mar. 1, 2002 (Atty. Docket No. INSL-118), and entitled FLOW CONDITION SENSOR ASSEMBLY FOR PATIENT INFUSION DEVICE, which is assigned to the assignee of the present application and incorporated herein by reference.
• While the exemplary embodiment of theflow path assembly16 ofFIGS. 3 and 11 includes theflow sensor assembly30 in fluid communication with the auxiliarychamber inlet port108 and the auxiliarychamber outlet port112 of thebase layer100, the auxiliarychamber inlet port108 and the auxiliarychamber outlet port112 can be used to attach other types of “auxiliary” sensors or devices to theflow path assembly16. For example, an auxiliary sensor connected to the auxiliarychamber inlet port108 and the auxiliarychamber outlet port112 can be provided to not only detect flow conditions but other parameters such as detection of air, temperature monitoring, drug parameter monitoring (concentration, pH, etc.) and other parameters important to infusion of liquid therapeutics, in addition to flow rate. An auxiliary device can include an air removal filter, a fluid sterilization filter, a pressure release valve, and other types of devices as desired.
• Referring toFIG. 3, thefirst surface102 of thebase layer100 defines areservoir shelf126 connecting thereservoir58 inlet port and thereservoir outlet port44. Thereservoir12 includes thecylindrical side wall42 having opposing open ends, and one of the open ends is received in a fluid-tight manner on theshelf126 of thebase layer100 so that a interior chamber of thereservoir12 is in fluid communication with thereservoir inlet port58 and thereservoir outlet port44 of thebase layer100. Theside wall42 of thereservoir12 can be made of any suitably strong and rigid material that is compatible with the fluid to be held by thereservoir12 and that can be sterilized. In one exemplary embodiment, theside wall42 is comprised of stainless steel (inFIG. 3 theside wall42 is shown as being transparent only for purposes of illustration). It is also contemplated that theside wall42 can be formed unitarily as a single piece with thebase layer100, if desired.
• Referring now toFIGS. 6 through 9, anotherfluid delivery device130 constructed in accordance with the present invention is shown. Thefluid delivery device130 includes ahousing132 having aport134, anadhesive layer136 provided on an exterior surface of thehousing132 surrounding theport134 and including resilientlyflexible flaps138 normally sealing theport134 in a substantially fluid-tight manner. Theadhesive layer136 is for securing thedevice130 to a patient during use.
• Aprotective layer140 removably covers theadhesive layer136 and includes asterilization access tube142 extending through theflaps138 of theadhesive layer136 and into thehousing132. Among other benefits and features, thesterilization access tube142 allows a fluid or gas, such as a sterilization medium (e.g., ethylene oxide), to enter theport134 from outside thehousing132 prior to removal of theprotective layer140. Theflaps138 then seal theport134 in a fluid-tight manner after removal of theprotective layer140, to reduce the risks of contamination of thefluid delivery device130 during use.FIGS. 6 and 7 shown thedevice130 prior to removal of theprotective layer140, whileFIGS. 8 and 9 show thedevice130 after removal of theprotective layer140. Theport134 may also be used for passage of a deployable cannula or other transcutaneous access tool (not shown), or may be provided just to allow access of a sterilization medium through thesterilization access tube142 prior to use.
• Referring toFIG. 12, another exemplary embodiment of areservoir150 constructed in accordance with the present invention is shown. Thereservoir150 includes acylindrical side wall152 having opposing first and second open ends154,156 and defining a reservoir chamber, anend cap158 closing the secondopen end156 of theside wall152 and defining aport160 providing fluid communication with the reservoir chamber, aplunger162 received in the reservoir chamber and slidingly moveable along theside wall152 and between the opposing first and second open ends154,156, and alead screw164 extending into the firstopen end154 of theside wall152 and having a distal end secured to theplunger162.
• In the exemplary embodiment ofFIGS. 12 and 13, a resiliently flexible o-ring166 is provided in a circumferential groove of theplunger162 to maintain a fluid-tight seal between theplunger162 and theside wall152 of thereservoir150. The distal end of thelead screw164 is preferably rotatably secured within asocket168 of theplunger162 so that thelead screw164 can be rotated independently of theplunger162. In addition, the distal end of thelead screw164 is preferably snap-fit into thesocket168 for ease of assembly. Theend cap158 is made of a suitably rigid and strong material that is compliant with the fluid to be held in thereservoir150 and that can be easily sterilized, such as stainless steel. Theend cap158 can be secured to theside wall152 by welding for example.
• An exemplary embodiment of a flow path assembly constructed in accordance with the present invention includes thereservoir150 ofFIGS. 12 and 13 assembled to abase layer170 ofFIG. 14. Thebase layer170 has opposing first and second surfaces172 (only the second surface is viewable inFIG. 14), a fillchamber outlet port174 extending through thebase layer170 and between the opposing first and second surfaces, areservoir inlet port176 extending through thebase layer170 and between the opposing first and second surfaces, areservoir outlet port178 extending through thebase layer170 and between the opposing first and second surfaces, and acannula inlet port180 extending through thebase layer170 and between the opposing first and second surfaces. Thesecond surface172 of thebase layer170 defines afirst groove182 connecting the fillchamber outlet port174 to thereservoir inlet port176, and asecond groove184 connecting thereservoir outlet port178 to thecannula inlet port180.
• The first surface of thebase layer170 defines areservoir recess186 connecting thereservoir inlet port176 and thereservoir outlet port178 and for receiving theend cap158 of thereservoir150 ofFIG. 12 in a substantially fluid-tight manner. Theport160 of theend cap158 provides fluid communication between thereservoir150 and thereservoir inlet port176 and thereservoir outlet port178. During assembly, theend cap158 of thereservoir150 is snap-fit into thereservoir recess186 of thebase layer170.
• Referring toFIG. 14, the first surface of thebase layer170 also defines afill port recess188 over the fillchamber outlet port174 and acannula connector recess190 over thecannula inlet port180. Thebase layer170 is made of a suitable strong and rigid material, such as injection molded plastic or stainless steel. Although not shown, the flow path assembly further includes a cover layer secure over thesecond surface172 of thebase layer170 in a fluid-tight manner such that thegrooves182,184 are formed into fluid passageways. Among other benefits and features, the mating construction of thereservoir150 and thebase layer170 ofFIGS. 12 through 14 simplifies assembly (and thus the cost) of the resulting fluid delivery device.
• Referring toFIGS. 15 and 16, an additionalflow path assembly200 constructed in accordance with the present invention is shown. In general, theflow path assembly200 ofFIGS. 15 and 16 is unitarily formed as part of anend wall202 of ahousing204 of a fluid delivery device. Among other benefits and features, theflow path assembly200 ofFIGS. 15 and 16 simplifies assembly (and thus the cost) of the fluid delivery device by incorporating the flow path into theend wall202 of thehousing204, which can be two injection moldedpieces206,208 assembly together.
• In the exemplary embodiment shown, theflow path assembly200 includes afirst portion206 and asecond portion208 of thehousing204 assembled together to form theend wall202 of the housing. Theend wall202 includes afill port210, areservoir connection port212, acannula connection port214, and at least oneflow path216 connecting the fill port, the reservoir connection port and the cannula connection port.
• In the exemplary embodiment shown, thefirst portion206 of thehousing204 includes a first portion of theend wall202 and thesecond portion208 of thehousing204 includes a second portion of theend wall202. The first and the second portions of theend wall202 have mating surfaces defining corresponding grooves which together define theflow path216 of the end wall when the first and thesecond portions206,208 of thehousing204 are assembled together.
• Theend wall202 of thehousing204 further includes an interior surface defining areservoir recess218 in fluid communication with thereservoir connection port212, and areservoir side wall220 is received in therecess218. A circumferential o-ring groove is provided in thereservoir recess218, and a resiliently flexible o-ring222 is positioned in the groove to provide a fluid-tight seal between theside wall220 of the reservoir and theend wall202 of thehousing204. Thefill port210 extends between the mating surface of the second portion of theend wall202 and an exterior surface of thesecond portion208 of thehousing204, and contains aneedle septum224.
• As illustrated by the above described exemplary embodiments, the present invention generally provides new and improved components for a device for delivering fluid, such as insulin for example, to a patient. It should be understood that the embodiments described herein are merely exemplary and that a person skilled in the art may make variations and modifications to the embodiments described without departing from the spirit and scope of the present invention. All such equivalent variations and modifications are intended to be included within the scope of this invention as defined by the appended claims.

Claims (13)

1. A fluid delivery device comprising:

a housing;

a reservoir positioned within the housing; and

a transcutaneous access tool positioned within the housing and including,

a cannula in fluid communication with the reservoir and linearly moveable along an axis of the transcutaneous access tool through a port in a wall of the housing,

a deployment member secured to the cannula and movable along the axis of the transcutaneous access tool against the wall of the housing defining the port, and

an annular seal coaxially positioned about the cannula and positioned between the deployment member and the wall of the housing defining the port, so that the seal provides a substantially fluid-tight seal between the deployment member and the wall of the housing when the deployment member is moved against the wall of the housing.

2. A device according toclaim 1, wherein the annular seal is secured to the deployment member.

3. A device according toclaim 1, wherein the annular seal comprises at least one of an elastomer and rubber.

4. A device according toclaim 1, wherein the cannula comprises a flexible cannula.

5. A device according toclaim 1, wherein the transcutaneous access tool further comprises a deployment spring biasing the deployment member towards the port in the wall of the housing.

6. A device according toclaim 5, wherein the transcutaneous access tool further includes a deployment latch mechanism maintaining the deployment member against the bias force of the deployment spring.

7. A device according toclaim 6, wherein the deployment latch mechanism comprises:

a movable latch positioned in the path of the deployment member to maintain the deployment member against the bias force of the deployment spring; and

an elongated shape memory element having a changeable length decreasing from an uncharged length to a charged length when at least one charge is applied to the shape memory element, the shape memory element connected between the latch and a fixed portion of the device such that the changeable length of the shape memory element decreasing from an uncharged length to a charged length causes the latch to be moved out of the path of the deployment member.

8. A device according toclaim 1, wherein the cannula of the transcutaneous access tool comprises a first cannula and the transcutaneous access tool further includes:

a second cannula disposed within the lumen of the first cannula; and

a retraction member secured to the second cannula and movable along the axis of the transcutaneous access tool with respect to the deployment member.

9. A device according toclaim 8, wherein the transcutaneous access tool further comprises a retraction spring biasing the retraction member away from the deployment member.

10. A device according toclaim 8, wherein the first cannula is flexible and the second cannula is rigid.

11. A device according toclaim 1, further comprising an outlet plug removably connected to a distal end of the cannula.

12. A device according toclaim 11, wherein the outlet plug includes an air removal filter allowing air to exit the cannula.

13. A device according toclaim 11, wherein the port in the wall of the housing comprises an internal exit port and the housing further includes an external exit port for the flexible cannula and a sterilization access port adjacent the external exit port.

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