Surgery – Means for introducing or removing material from body for... – Treating material introduced into or removed from body...
Reexamination Certificate
2002-04-23
2003-12-02
Kennedy, Sharon (Department: 3762)
Surgery
Means for introducing or removing material from body for...
Treating material introduced into or removed from body...
C604S151000
Reexamination Certificate
active
06656158
ABSTRACT:
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 a dispenser for a fluid delivery device that utilizes a shape memory element.
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 are still desired are new and improved components, such as dispensers and reservoirs, for a device for delivering fluid to a patient. Preferably, the components will be simple in design, and relatively compact, lightweight, easy to manufacture and inexpensive, such that the resulting fluid delivery device can be effective, yet inexpensive and disposable.
SUMMARY OF THE INVENTION
The present invention provides a device for delivering fluid, such as insulin for example, to a patient. The device includes an exit port assembly, a reservoir including a side wall extending towards an outlet connected to the exit port assembly, and a threaded lead screw received in the reservoir and extending towards the outlet of the reservoir. A plunger is secured to the lead screw and has an outer periphery linearly slideable along the side wall of the reservoir. The plunger and the lead screw are operatively arranged such that rotation of the lead screw in a first direction causes the plunger to slide along the side wall towards the outlet of the reservoir, which in turn causes fluid within the reservoir to be dispensed to the exit port assembly.
The device also includes a dispenser having a gear secured to the lead screw, and a moveable pawl positioned for contacting teeth of the gear during reciprocating linear movement of the moveable pawl adjacent the gear in first and second opposing linear directions. The pawl and the teeth are shaped such that linear movement of the pawl past the gear in the first linear direction causes rotation of the gear in the first rotational direction, while linear movement of the pawl past the gear in the second linear direction causes no rotation of the gear.
The dispenser also includes 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 is connected between the moveable pawl such that the changeable length of the shape memory element decreasing from an uncharged length to a charged length causes linear movement of the moveable pawl past the gear in one of the first and the second linear directions. The use of a shape memory element helps provide a dispenser that is simple in design, and relatively compact, lightw
Flaherty J. Christopher
Garibotto John T.
Gregory Christopher Carter
Mahoney Derek Dwayne
Margicin John Michael
Insulet Corporation
Kennedy Sharon
McDermott & Will & Emery
LandOfFree
Dispenser for patient infusion device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Dispenser for patient infusion device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dispenser for patient infusion device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3094694