Abstract: A cassette for vaporization of anesthetic agent for delivery to a patient is arranged to be received by an anesthesia machine which has control mechanisms for controlling vaporization of the agent. In a preferred arrangement, the cassette includes a housing for receiving, containing and emitting anesthetic agent. A sensor, such as a pressure sensor or a temperature sensor is embedded in the housing for obtaining a value of the agent contained in the reservoir. The sensor is operatively connected to the reservoir to obtain an accurate value of the agent. A communication link is provided between the sensor and the control mechanisms of the anesthesia machine when the cassette is received by the anesthesia machine. The cassette thus provides a simplified arrangement that efficiently and accurately provides values of the anesthetic agent being vaporized in the reservoir.

Abstract: An emergency oxygen system that provides a flow of oxygen to the patient undergoing anesthesia in the event of a detected fault in the overall supply and mixing system of the anesthesia system. The normal design of such supply and mixing systems for an anesthesia system provides oxygen and at least one other gas that are mixed together in a desired proportion to be provided to a vaporizer and then to the anesthesia system as fresh gas. In the present system, a processor continuously monitors the output flows from those proportioning mixing valves. When the processor determines that those flows from the proportioning valves are off by a predetermined amount, indicative of a fault in the system, the processor immediately shuts off the supply of any gases other than oxygen and also provides a flow of oxygen to a bypass line that bypasses the oxygen proportioning valve, thus assuring a supply of oxygen to the patient despite the fault.

Abstract: An anesthetic vaporizer having a means of mixing the anesthetic agent with a relatively low flow of carrier gas or a larger amount of carrier gas. A valve is operable by the user to select between the high flow anesthesia where the carrier gas and anesthetic agent are mixed in a mixing chamber and the low flow anesthesia where the carrier gas and anesthetic agent are diverted directly into the patient circuit. Accordingly, the anesthetic vaporizer is usable for high flow anesthesia, however, when used for low flow, the diverted flow allows more rapid response by eliminating the large volume of the mixing chamber.