173 Case report: novel use of methoxyflurane (penthrox®) for severe pain on dressing changes in palliative care

<h3></h3> Methoxyflurane is a volatile liquid anaesthetic used for moderate-to-severe pain associated with trauma. It is self-administered by inhalation under medical supervision using a Penthrox® inhaler device. It can be used on alternate days and has a rapid onset of action. We describe a potential novel method for incident pain control in palliative patients in hospice and community. Case- A 61 year old lady with significant peripheral vascular disease was admitted to our hospice for symptom control. She had a left below knee amputation and an ischaemic right leg with painful ulceration. Due to frailty she was not for further amputation. Ulcer dressing changes were incredibly painful and pain remained for several hours after each change, despite attempts with significant pre-dressing medications. Background pain was well controlled on methadone and other analgesics. She and her family dreaded dressing changes, which needed to be done approximately every second day. Penthrox® was tried simultaneously with dressing changes and she experienced no pain, discomfort or distress during the procedure or following it. Multiple ulcers were able to be dressed during a single episode. She was mildly euphoric and pleasantly confused while using the Penthrox®, and slept after. She experienced no other side effects. As well as improving physical symptoms, Penthrox® led to improvement in emotional and psychological wellbeing by lessening the fear of dressing changes. The improvement was so significant that she was discharged home, and continued to use Penthrox® 3 times a week at home with district nurses doing the dressings for 4 weeks without adverse event before being readmitted for end of life care. <h3>Conclusion</h3> This case demonstrates the safe and effective use of Penthrox® in a hospice and subsequently community setting for severe pain on dressing changes. This novel medication should become part of Palliative Medicine’s armamentarium for uncontrollable incident pain.