Abstract: An anesthesia machine includes a breathing system for delivering a gas mixture, including an anesthetic gas, to a patient for inhalation and for collecting exhaled gas from the patient. A cannister flow communicates with the breathing system and removes carbon dioxide from the exhaled gas. A pressure relief valve includes a housing that defines a chamber in flow communication with the breathing system, a valve member for regulating a flow of gas from the breathing system into the chamber and venting gas into the chamber when pressure in the breathing system exceeds a pressure threshold setting, and a plunger for preventing the flow of gas into the chamber independent of the pressure in the breathing system without changing the pressure threshold setting. The cannister, pressure relief valve, and other components are secured to a manifold having internal flow channels.

Abstract: An anesthesia machine includes a breathing system for delivering a gas mixture, including an anesthetic gas, to a patient for inhalation and for collecting exhaled gas from the patient. A cannister flow communicates with the breathing system and removes carbon dioxide from the exhaled gas. A pressure relief valve includes a housing that defines a chamber in flow communication with the breathing system, a valve member for regulating a flow of gas from the breathing system into the chamber and venting gas into the chamber when pressure in the breathing system exceeds a pressure threshold setting, and a plunger for preventing the flow of gas into the chamber independent of the pressure in the breathing system without changing the pressure threshold setting. The cannister, pressure relief valve, and other components are secured to a manifold having internal flow channels.