Patent ID: 6520936
Filing Date: 2003-02-18
Classification: A61M

Abstract:
An implantable infusion pump for dispensing a fluid to a patent, comprising:a pump housing capable of being implanted in a body of a patient; an inlet in the housing for receiving the fluid to be dispensed, the inlet in the housing including a first septum and a second septum; an outlet in the housing from which fluid is dispensed; a first reservoir of variable size for holding the fluid, wherein the inlet and first reservoir are connected at least periodically by a flow path so as to allow fluid supplied to the inlet to flow to the first reservoir, and wherein the outlet and first reservoir are at least periodically connected by a flow path so as to allow fluid in the first reservoir to be dispensed through the outlet; a second reservoir of variable size for holding a gas; a volume comprising the first reservoir and the second reservoir, such that as the second reservoir expands in size the first reservoir diminishes in size; and a gas generating source for controllably and variably producing quantities of gas that expand the size of the second reservoir, thereby decreasing the size of the first reservoir to cause dispensing of fluid through the outlet to the patient.