A Pilot Study on the Use of Methoxyflurane (Penthrox®) for Pain Control in the Emergency Department

Each patient in the methoxyflurane group will use one Penthrox inhaler under supervision of trained personnel. After priming the inhaler with 3 mL of methoxyflurane, patient is instructed to inhale through the mouthpiece to obtain analgesia, and then exhale back into the mouthpiece so that any unmetabolized methoxyflurane can be adsorbed by activated charcoal chamber. First few breaths should be gentle and then breathe normally through Inhaler. Onset of pain relief is rapid and occurs after 6-10 inhalations. If stronger analgesia is required, patient can cover the diluter hole with a finger during inhalation. Patients are able to titrate the amount of methoxyflurane inhaled and should be instructed to inhale intermittently to achieve adequate pain control.

Each patient in the ketorolac group will receive one dose of 30mg intramuscular ketorolac injected at gluteal muscle by nursing staff as usual daily practice.