Oral Aspirin/ketamine versus oral ketamine for emergency department patients with acute musculoskeletal pain

Abstract

Objective: The purpose of this study is to investigate if an orally administered combination of aspirin and ketamine will provide better analgesia than a ketamine alone in adult patients presenting to the Emergency Department (ED) with acute musculoskeletal pain.

Methods: We conducted a prospective, randomized, open-label trial of ED patients aged 18 and older presenting with moderate to severe acute musculoskeletal pain as defined by an 11-point numeric rating scale (NRS) with an initial score of ≥5. Patients were randomized to receive either 324 mg of VTS-Aspirin™ and 0.5 mg/kg of oral ketamine (AOK) that is directly swallowed or 0.5 mg/kg of oral ketamine (OK) alone that is swished first and then swallowed. Patients were assessed at baseline, 30, 60, 90, and 120 min. The primary outcome was a difference in pain scores between the two groups at 60 min post-administration. Secondary outcomes included adverse events and the need for rescue analgesia.

Results: We enrolled 60 patients in the study (30 per group). The difference in mean pain scores at 60 min between the AOK and OK groups was 2.6 [95% CI: 1.38-3.77] showing a lower mean pain score in the OK group. At 60 min, the AOK group had a change in mean pain score from 8.4 to 6.3 (difference 2.1; 95% CI: 1.35-3.00). The OK group had a change in mean pain score from 7.8 to 3.7 (difference 4.1, 95% CI: 3.25-4.90). No clinically concerning changes in vital signs were observed. No serious adverse events occurred in either group. The most commonly reported adverse effects were dizziness and fatigue. None of the participants required rescue analgesia at 60 min post-medications administration.

Conclusion: The administration of an oral combination of VTS-Aspirin ™ and ketamine resulted in less analgesia compared to oral ketamine alone, for the short-term treatment of moderate to severe acute musculoskeletal pain in the ED.

Clinicaltrials: govRegistration: NCT04860804.

Keywords: Analgesia; Emergency department; Ketamine; Musculoskeletal pain; VTS-aspirin.