Inhaled fluorinated hydrocarbon volatile anesthetic
Penthrox®
EMR: Self-administered relief from moderate to severe pain in conscious, hemodynamically stable patients
Consider the CHECK mnemonic:
EMR: Self-administered relief from moderate to severe pain in conscious, hemodynamically stable patients
Patients must self-administer as needed under direct EMR or paramedic supervision
Not approved by Health Canada for use in patients under 18 years.
Methoxyflurane is a fast-acting inhaled fluorinated hydrocarbon volatile anesthetic. Unfortunately, like many anesthetic agents, the exact mechanism of action is not known.
Inhaled:
Doses of methoxyflurane that exceed therapeutic doses have been shown to produce serious, irreversible nephrotoxicity. Follow dosing guidelines and do not exceed recommended amounts.
Although unlikely in the out-of-hospital setting, patients should not receive more than 6 mL in any 24 hour period and no more than 15 mL over 1 week.
Methoxyflurane has a flashpoint of 62°C or, in a closed, oxygen-rich system, a flashpoint of 32.8°C. Do not store methoxyflurane in any space where temperatures exceed 40°C.
The Penthrox® activated carbon chamber must always be attached to the device during administration. When possible, fill the Penthrox® inhaler outside of the response vehicle (i.e., ambulance or aircraft) and begin administration in a well-ventilated space such as the patient's home or outdoors.
Follow vehicle safety considerations established for infectious diseases at all times during preparation and administration of methoxyflurane. Ensure the vehicle cab fan is on high, close the passthrough/partition window, and set the patient compartment exhaust to high.
EMRs and paramedics must limit their exposure to a maximum of three (3) doses (9 mL) total in any 24 hour period.