Abstract: A transcutaneous infusion system comprises an implantable infusate injection port for conducting infusate from the port to an infusion site in the body. The port is supplied with infusate through a penetrable septum located directly under the skin. To infuse the patient, a flexible injection cannula encircling a needle which is slightly longer than the cannula is inserted through the septum into the port and then the needle is withdrawn leaving the free end of the flexible cannula in the port. The opposite end of the cannula is provided with a fitting for connecting the cannula to the outlet of a fluid administration set. The system also includes a bracket removably connected to the cannula and taped to the patient adjacent the injection site so that the bracket anchors the cannula and its associated fittings and tubing against the patient's skin, while assuring that the cannula is not bent to an extent that will stop fluid flow into the port.

Abstract: Infusion apparatus includes a housing with an infusate chamber in the housing and means for conducting infusate from the chamber through a restrictive outlet passage to an additional small chamber having an entrance port closed by a self-sealing penetrable septum. An exit tube from the small chamber leads directly to a cannula at the infusion site so that liquid can be injected into the small chamber through its septum and delivered directly to the infusion site without backflowing into the infusate chamber.

Abstract: Implantable variable flow infusion apparatus comprises a collapsible infusate chamber having an outlet conduit leading to the infusion site by way of series-connected fixed and variable fluid flow restrictors. The infusate in the chamber is maintained under substantially constant pressure by a nonelectric energy storage cell to establish flow from the chamber to the site. The variable restrictor is controlled by commands from a preprogrammed microprocessor and programmable memory powered by a small long-lived battery. The processor sets the variable restrictor to the proper setting to establish the correct infusate flow for the particular time of day. A pressure transducer connected across the fixed restrictor senses the pressure differential across the fixed restrictor which differential indicates actual infusate flow from the chamber.

Abstract: A programmable implantable infusion pump includes a housing containing a variable volume infusate chamber and variable volume control fluid pressure and displacement reservoirs. A conduit conducts infusate from the chamber exteriorly of the housing. A restricted fluid path exists between the two reservoirs which are filled with an incompressible control fluid. A loaded spring applies a constant force to the pressure reservoir causing fluid flow between the two reservoirs. The differential pressure across the flow restriction is sampled by a microprocessor which computes the fluid flow rate, that rate being proportional to the infusate flow rate from the chamber. When the fluid flow rate deviates from a programmed value, the processor issues an error command to a battery-driven motor which reloads the spring to reestablish the constant force on the pressure reservoir.

Abstract: Apparatus for locating the septum through which an implanted prosthetic device is refilled with infusate includes means mounted in the device in juxtaposition with the septum for producing an energy pattern that extends outside the body. The pattern is shaped so as to indicate the location under the skin of the septum of the implanted device. The apparatus also includes a small portable detector which is responsive to the radiation pattern emanating from the body. The detector is arranged so that when manipulated over the patient's body at the approximate site of the implanted device, it designates the location of the septum.