Oxygen supply for implantable medical device

A method for replenishing gas in a subcutaneously implanted medical device containing functional cells comprising:

• inserting at least one needle capable of penetrating the skin and connecting to the subcutaneously implanted medical device;
• connecting said at least one needle to a gas replenishing apparatus;
• extracting gas from a gas reservoir in the implanted medical device into said gas replenishing apparatus;
• sensing oxygen level in the gas extracted from said gas reservoir;
• calculating the amount of gas needed for replenishing oxygen in said gas reservoir based on the sensed oxygen level in the extracted gas;
• and
• supplying gas from a gas tank in said gas replenishing apparatus to said gas reservoir in the implanted medical device.

A method for replenishing gas in a subcutaneously implanted medical device containing functional cells comprising:

• inserting at least one needle capable of penetrating skin and connecting to a subcutaneously implanted medical device;
• connecting said at least one needle to a gas replenishing apparatus;
• measuring a gas pressure in a gas reservoir in the implanted medical device;
• calculating the amount of gas needed for replenishing oxygen in said gas reservoir based on sensed pressure in the extracted gas;
• and
• supplying gas from a gas tank in said gas replenishing apparatus to said gas reservoir in the implanted medical device.

A system for maintaining functional cells in medical device subcutaneously implanted in a patient body comprising:

• a gas reservoir provided within the implanted medical device;
• a gel layer disposed with a plurality of the functional cells, wherein said gel layer is capable of protecting the functional cells from the body immune system by a first membrane, and wherein said gel layer is capable of receiving oxygen from said gas reservoir;
• and
• at least one gas port provided to the implanted medical device that is capable of receiving replenishing gas supply;
• gas replenishing apparatus located outside the patient body and capable of supplying replenishing gas to said gas reservoir through said at least one gas port wherein said gas replenishing apparatus comprising:
• at least one needle capable of penetrating the skin of the patient body and connecting to the implanted medical device through said at least one gas port;
• a gas tank holding gas for replenishing gas;
• a gas handling sub-system capable of supplying gas from said gas tank into said gas reservoir;
• at least one gas sensor selected from an oxygen sensor for sensing oxygen level in the gas;
• and a pressure transducer for measuring pressure in said gas reservoir;
• and
• a processor capable of controlling said gas handling sub-system in response to reading of said at least one of said oxygen sensor and said pressure transducer.