Acute pain management research in the emergency department - considerations for model development

Acute pain management trials are often conducted with operative procedures (dental, orthopedic, abdominal). However, there are other acute painful models that are not post-operative and may respond to analgesic therapy differently. One such model involves pain following acute trauma. This model is complicated by the environment in which these patients are studied – the Emergency Department (ED). We evaluated an intranasal analgesic under development in an open-label, ascending dose design with pain following acute trauma. Our goal was to understand the origin and severity of the pain and its response to analgesic treatment. We further examined the dynamics of enrolling and completing well-controlled trials in this environment. Patients (113) were enrolled in this trial at five ED centers over 8 months. Two sites accounted for 81% of the patients enrolled. One site (51 patients) was a rural hospital with a relatively small population served while the other (40 patients) was a large teaching hospital. Most patients were male (68%) and in the 18-29 year old group (33%). Injuries included sprains and strains (46%), fractures (33%), blunt trauma (5%), compression crush injuries (3.5%), lacerations (2.5%) and burns (1.7%). The mean baseline pain intensity reported by patients on a 0-10 scale was 8.02. Pain was reduced with the most effective dose of analgesic by 24% in 10 minutes and 43% in 30 minutes post intranasal administration. Patients following acute trauma experiencing moderate to severe pain were responsive to an intranasal analgesic. While the busy EDs present large populations to study, smaller hospital settings can offer equal quality and efficiency. Injuries mostly involved sprains, strains and fractures. We conclude that the acute trauma patient population is suitable for study of pain; can be successful in small and large EDs; and has significant need for rapid onset analgesia.

Supported by Intranasal Therapeutics, Inc.