Anesthesia vaporizer reservoir and system

A vaporizer reservoir for an anesthesia vaporizer system, the vaporizer reservoir configured to contain liquid anesthetic agent and to be refilled by a refill container containing liquid anesthetic agent, the vaporizer reservoir having a length between a first end and a second end, the vaporizer reservoir comprising:

• a piston in the vaporizer reservoir, wherein the piston forms a first chamber at the first end of the vaporizer reservoir;
• wherein the piston is movable along the length of the vaporizer reservoir between a first position within the vaporizer reservoir and a second position within the vaporizer reservoir, wherein the volume of the first chamber increases as the piston moves from the first position to the second position, wherein the first chamber of the vaporizer reservoir has a larger maximum volume than the refill container;
• a fill port configured to removably receive the refill container containing liquid anesthetic agent;
• a valve in the fill port configured to permit flow of the liquid anesthetic agent from an exterior of the vaporizer reservoir into the first chamber;
• wherein the system is configured such that as the piston moves from the first position towards the second position, the liquid anesthetic agent is drawn from the refill container into the first chamber;
• a sump chamber configured to contain liquid anesthetic agent, the sump chamber at the second end of the vaporizer reservoir;
• a transfer valve configured to permit the liquid anesthetic agent to flow from the first chamber into the sump chamber;
• and
• an outlet port that delivers the liquid anesthetic agent from the sump chamber to a vaporizing system that vaporizes the liquid anesthetic agent for delivery to a patient.