Implantable microsphere reservoir
A drug delivery system including an implantable reservoir containing drug microspheres, with an innocuous fluid flushed through the implantable microsphere reservoir to form a drug containing solution for delivery within a body of a patient.
1 . An implantable medical device, comprising:
an access port configured to receive a percutaneous injection of an amount of innocuous fluid;
a fluid receptacle chamber fluidly coupled to the access port and configured to receive the percutaneous injection of the amount of innocuous fluid;
a microsphere reservoir comprising microspheres containing a quantity of therapeutic agent, the microsphere reservoir being fluidly coupled to the fluid receptacle chamber and configured to receive the amount of innocuous fluid, wherein the microspheres are configured to elude less than the quantity of the therapeutic agent into the amount of innocuous fluid to form a therapeutic agent solution having an equilibrium concentration of the therapeutic agent, and wherein further release of the therapeutic agent from the microspheres ceases upon reaching the equilibrium concentration; and
a catheter access chamber between and fluidly coupled to the microsphere reservoir and a catheter connector, the catheter access chamber being configured to receive the therapeutic agent solution and enable at least one of sampling of the therapeutic agent solution prior to delivery, checking a patency of a delivery route to a targeted delivery site within a body of a patient, sampling fluid from the patient, or delivering another agent.
2 . The implantable medical device of claim 1 , wherein the catheter connector is fluidly coupled to a catheter implanted within the body of the patient for delivering the therapeutic agent solution.
3 . The implantable medical device of claim 1 , wherein the fluid receptacle chamber comprises a self-sealing septum.
4 . The implantable medical device of claim 1 , wherein the fluid receptacle chamber comprises one or more positional markers or tactile feedback mechanisms.
5 . The implantable medical device of claim 4 , wherein the one or more positional markers comprise at least one of: a light emitting diode, an acoustic device, a wireless location/orientation sensor, or a combination thereof, as an aid in properly positioning a needle of a percutaneous injection device within the fluid receptacle chamber.
6 . The implantable medical device of claim 1 , wherein the fluid receptacle chamber comprises one or more needle detection sensors.
7 . The implantable medical device of claim 6 , wherein the one or more needle detection sensors comprise at least one of: a mechanical switch, a resonant circuit, an ultrasonic transducer, a voltmeter, an ammeter, an ohmmeter, a pressure sensor, a flow sensor, a capacitive probe, an acoustic sensor, an optical sensor, or a combination thereof, configured to detect a presence of a needle of a percutaneous injection device within the fluid receptacle chamber.
8 . The implantable medical device of claim 1 , further comprising one or more physiological sensors.
9 . The implantable medical device of claim 8 , wherein the physiological sensors comprise at least one of: a heart rate sensor, a respiratory sensor, a pulse oximeter, a blood pressure sensor, an intracranial pressure sensor, a cerebrospinal fluid pressure sensor, an intra-abdominal pressure sensor, a temperature sensor, or a combination thereof.
10 . The implantable medical device of claim 1 , further comprising a transceiver circuit configured to wirelessly receive information from and transmit information to at least one of an external programmer or a server.
11 . The implantable medical device of claim 1 , further comprising a clock/calendar element and an alarm drive configured to activate one or more notifications, alerts, or alarms.
12 . The implantable medical device of claim 1 , further comprising a memory configured to maintain an access log of the fluid receptacle chamber.
13 . The implantable medical device of claim 1 , further comprising at least one flow sensor configured to monitor a flow of fluid through the implantable medical device.
14 . The implantable medical device of claim 1 , further comprising a filter positioned upstream of the microsphere reservoir and a second filter positioned downstream of the microsphere reservoir.
15 . The implantable medical device of claim 14 , wherein at least one of the first filter or the second filter is configured to inhibit a flow of particles having a nominal diameter in a range of between about 1 μm and about 1000 μm.
16 . The implantable medical device of claim 1 , wherein the therapeutic agent is encapsulated inside the microspheres, dissolved into a matrix of the microspheres, or attached to the microspheres via one or more binding sites.
17 . The implantable medical device of claim 1 , wherein the access port comprises one or more needle detection sensors.
18 . An implantable medical port, comprising:
an access port configured to receive a percutaneous injection of an amount of innocuous fluid;
a fluid receptacle chamber fluidly coupled to the access port and configured to receive the percutaneous injection of the amount of innocuous fluid;
a microsphere reservoir comprising microspheres containing a quantity of therapeutic agent, the microsphere reservoir being fluidly coupled to the and fluid receptacle chamber and configured to receive the amount of innocuous fluid, wherein the microspheres are configured to elude less than the quantity of the therapeutic agent into the amount of innocuous fluid to form a therapeutic agent solution having an equilibrium concentration of the therapeutic agent in the fluid, and wherein further elution of the therapeutic agent from the microspheres ceases upon reaching the equilibrium concentration;
a catheter access chamber fluidly coupled to the microsphere reservoir, the catheter access chamber being configured to receive the therapeutic agent solution from the microsphere reservoir; and
a catheter connector fluidly connected to the catheter access chamber and configured to enable the implantable medical port to be selectively coupled to a catheter implanted within a body of a patient,
wherein the catheter access chamber is configured to enable at least one of sampling of the therapeutic agent solution prior to delivery within the body of the patient, checking a patency of a delivery route to a targeted delivery site within the body of the patient, sampling fluid from the patient, or delivering another agent, and
wherein a risk of an accidental overdose due to percutaneous injection of an excess amount of innocuous fluid through the access port is reduced because only a small additional amount of the therapeutic agent is eluded into the excess amount of innocuous fluid that flows through the microsphere reservoir until the equilibrium concentration of the therapeutic agent is reached in the excess amount of innocuous fluid.
19 . The implantable medical port of claim 18 , wherein the catheter connector is fluidly coupled to a catheter implanted within the body of the patient for delivering the therapeutic agent solution.
20 . The implantable medical port of claim 18 , wherein the therapeutic agent is encapsulated inside the microspheres, dissolved into a matrix of the microspheres, or attached to the microspheres via one or more binding sites.
21 . An implantable medical system, comprising:
an implantable microsphere reservoir comprising microspheres containing a quantity of therapeutic agent;
an implantable pump in fluid connection with the implantable microsphere reservoir, the implantable pump configured to pump an amount of innocuous fluid from a fluid receptacle chamber into the implantable microsphere reservoir, wherein the microspheres contained within the microsphere reservoir are configured to elude less than the quantity of the therapeutic agent into the innocuous fluid to form a therapeutic agent solution having an equilibrium concentration of the therapeutic agent, and wherein further dissolution or elution of the therapeutic agent from the microspheres ceases upon reaching the equilibrium concentration; and
a catheter access chamber fluidly coupled to the implantable microsphere reservoir and a catheter connector, the catheter access chamber being configured to receive the therapeutic agent solution, the catheter connector being configured to enable the implantable medical system to be selectively coupled to a catheter implanted within a body of a patient,
wherein the implantable pump comprises the fluid receptacle chamber reservoir and a refill port, and
wherein the refill port is configured to enable at least one of sampling of the therapeutic agent solution prior to delivery within the body of the patient, checking a patency of a delivery route to a targeted delivery site within the body of the patient, sampling fluid from the patient, or delivering another agent.
22 . The implantable medical system of claim 21 , wherein the refill port is in fluid communication with the fluid receptacle chamber of the implantable pump and configured to receive the amount of innocuous fluid percutaneously.
23 . The implantable medical system of claim 21 , wherein the therapeutic agent is encapsulated inside the microspheres, dissolved into a matrix of the microspheres, or attached to the microspheres via one or more binding sites.