Date: February 18th, 2021

Guest Skeptic: Dr. Chris Bond is an emergency medicine physician and assistant Professor at the University of Calgary. He is also an avid FOAM supporter/producer through various online outlets including TheSGEM.

Reference: Brichko et al. Rapid Administration of Methoxyflurane to Patients in the Emergency Department (RAMPED): A Randomised controlled trial of Methoxyflurane vs Standard care. AEM Feb 2021.

Case: A 46-year-old female presents to the emergency department (ED) with sudden onset, severe right flank pain. She is pacing around at triage in tears and says she has a history of kidney stones. She is asking for something to help with her pain, but the department is very busy, and it will be some time before she can get into a treatment space.

Background: Pain is the primary reason patients present to the emergency in many cases (1-6).  Oligoanalgesia is the term used to describe poor pain management through the under use of analgesia (7-11).  Effective pain management is an important indicator of the quality of patient care (12).

Multiple factors have been thought to contribute to oligoanalgesia (overcrowding, language barriers, age, gender, ethnicity, insurance status) (13-16).  Delays in providing adequate analgesia leads to poorer patient outcomes, prolonged ED length of stay and reduced patient satisfaction (17, 18).

It can take a long time for someone in severe pain to receive an analgesic in the ED. Previous research in Australia has shown that the median time can be between 40-70 minutes for analgesia administration (19, 20).

Delays are not unique to Australia and a study done in the USA reported a mean of 116 minutes for patients presenting to the ED with pain to receive analgesia (21). To minimize delays, different strategies have been implemented to address the problem (advanced protocols, provision of oral analgesics at triage, and the use of novel analgesic agents that do not require intravenous access) (22).

Recently, there has been increased interest in using methoxyflurane (Penthrox), an inhaled non-opioid analgesic, to provide rapid short-term analgesia (23, 24).  In Australia, Methoxyflurane has been widely used at sub-anesthetic doses for analgesia in the pre-hospital setting since 1975. Its use has become more global in recent years and at low doses, it has a very reassuring safety profile.

Furthermore, there have been no reports of addiction or abuse related to these inhaler devices (25-28). The majority of studies of methoxyflurane for pain focus on traumatic pain, this study aimed to assess its effectiveness in treatment of both traumatic and non-traumatic pain.

Clinical Question: What is the effectiveness of methoxyflurane versus standard care for the initial management of severe pain among adult ED patients?

Reference:  Brichko et al. Rapid Administration of Methoxyflurane to Patients in the Emergency Department (RAMPED): A Randomised controlled trial of Methoxyflurane vs Standard care. AEM Feb 2021.

* Population: Adult patients aged 18-75 years with severe pain defined as an initial Numerical Rating Scale (NRS) pain score greater than or equal to 8.

* Exclusion criteria: Transferred patients, HR <40 or >140 bpm, SBP <90 or >180 mmHg, RR <6 or >36/min, GCS <15, possible ACS, headache, pregnancy, breastfeeding, known renal or hepatic failure, previous malignant hyperthermia, known sensitivity to fluorinated anesthetics, or agitated/aggressive per nursing staff.

* Intervention: Inhaled Methoxyflurane 3 mL

* Comparison: Standard analgesic care which could include paracetamol,