Penthrox Versus Tramadol for SCDF

Introduction Current practice in Singapore Emergency Ambulance Service (EAS) includes the use of analgesia delivered via inhalation Enthanox (Nitrous Oxide). However there are difficulties administering Enthanox on-scene due to the added weight of carrying bulky cylinder tanks. It is common for a delay in administration of analgesia. Inhaled methoxyflurane (Penthrox) is a potential agent for early administration of analgesia by Singapore Civil Defense Force (SCDF) EAS. It is extensively used in the pre-hospital setting in Australia. However data on its use as an analgesic agent in general are limited and there are few published controlled trials of methoxyflurane in an analgesic role. Intramuscular (IM) tramadol is a common medication used in the hospital setting for analgesia. It is well proven, simple to deliver and is not a controlled drug. Aim To compare Penthrox and Tramadol in the treatment of acute pain in patients transported by the SCDF EAS. Methodology The trial will recruit 400 eligible patients over 1 year (200 Penthrox and 200 tramadol). Patients managed by SCDF EAS for treatment of acute pain and who meet the eligibility criteria will be recruited into the study. Half of SCDF's 30 ambulances (15 ambulances), will be randomly assigned, equipped and trained to carry the new medication (Penthrox). The other half (15 ambulances), will be trained and equipped with tramadol. Allocation will be on a per station level. After 6 months, they will cross over to Penthrox and tramadol respectively. All paramedics will be trained to use both medications, pain scales and Ramsey scores, and will record patient's pain, sedation scores and patient satisfaction as part of routine clinical practice. All patients will be followed up by a review of their Emergency Department and hospital records for any medication related adverse effects. Hypothesis The investigators hypothesize that in patients with acute pain (pain score ≥3), presenting to the ambulance service wi