Supplementing Pain management in the emergency department – Conventional treatment versus Intravenous Adjunctive Low dose Ketamine: A single blind randomised control trial of ketamine versus opioids for trauma patients with moderate to severe pain

Pain is a common feature of major traumatic injuries. Little research has been done into the utilisation of low dose Ketamine for analgesia in the ED. Ketamine has the potential to be a highly effective method of analgesic management in haemodynamically unstable trauma patients who are unsuitable for large doses of opioid drugs but it is not utilised for this purpose due to a lack of supporting evidence and clinical concern about potential side effects. The clinical impact of this trial is in the development of an evidence base to support the use of Ketamine for analgesic purposes in the ED. Our hypothesis is that low-dose Ketamine provides effective (statistically significant reduction in pain score), safe (low rates of emergence and adverse events) and tolerable (patient reported effects/willingness to use again) analgesia when used in sub-anaesthetic doses in patients with traumatic injuries. If proven this will have significant implications for the clinical care of patients and in pain management guidelines with traumatic injuries in the ED. The proposed research design is a single blind randomised trial of low dose Ketamine in trauma patients. Participants will be randomised to receive a single dose of 'study drug' which will be either Ketamine (0.2mg/kg) or IV opiate (the dose determined by the clinician), this will be followed up by ongoing standard care for pain management (intravenous morphine or equivalent). Participants will record pain scores every 15 minutes for one hour post analgesic dose. Participants will also be clinically assessed every 15 minutes and have their vital signs and any side effects recorded. Additional 'rescue' analgesia will be available across both arms to ensure that patients are treated for ongoing pain.Rescue analgesia use will also be recorded during the follow up period. Participants will be followed up 24-72hours after trial enrolment. Participants will have their vital signs recorded, will be assessed for adverse effects from the study drug and will be asked to complete a participant questionnaire. This short questionnaire will assess patient's satisfaction with pain management in the emergency department, their satisfaction with the 'study drug', any side effects experienced from the 'study drug' and their overall willingness to receive the 'study drug' again. Patients will be contacted at 6 and 12 months post enrolment to evaluate patient satisfaction and long term safety of Ketamine as an analgesic.