Methods and apparatus for high gas flow

A system comprising:

• a patient interface;
• a flow source;
• and
• a controller configured to:
• provide a first flow rate of gas flow to a patient interface during preoxygenation of a patient;
• and
• provide a second flow rate of gas flow to the patient interface when anesthetic drugs are administered during an anesthetic procedure.

A method of providing respiratory support to a patient during an anesthetic procedure, the method comprising:

• providing a first flow rate of gas flow during preoxygenation of the patient;
• and
• providing a second flow rate of gas flow when anesthetic drugs are administered during the anesthetic procedure,
• wherein the second flow rate of gas flow is higher than the first flow rate of gas flow, wherein the first flow rate of gas flow and the second flow rate of gas flow are each greater than 15 L/min.