We compared analgesic efficacy and safety of sub-dissociative dose ketamine (SDK) to morphine for managing acute traumatic pain in geriatric emergency department (ED) patients.
A subset of geriatric patients from a randomized double-blind trial experiencing moderate to severe acute traumatic pain who received SDK at 0.3 mg/kg or morphine at 0.1 mg/kg by short intravenous infusion over 15 minutes was analyzed at 15, 30, 60, 90, and 120 minutes post-medication administration. Primary outcome was reduction in pain at 30 minutes. Secondary outcomes included adverse effects and rates of rescue analgesia.
Twelve patients (5 in the SDK group and 7 in the morphine group) were eligible for analysis. The change in mean pain scores was not significantly different in SDK and morphine groups: 8.6 versus 9.1 at baseline and 5.8 versus 5.9 at 30 minutes. Patients in SDK group had a greater percentage change in pain reduction from the baseline in comparison to morphine at the 15-minute mark (48.8% decrease versus 30.8% decrease). In the morphine group more, patients experienced dizziness (57% vs. 20%) and fatigue (71% vs. 40%), and required more rescue analgesia at 60, 90 and 120 minutes (14% vs. 0%; 14% vs. 0%, and 29% vs. 0%, respectively).
SDK at 0.3 mg/kg over 15 minutes provided analgesia comparable to morphine for short-term treatment of acute pain with a reduced need for rescue analgesia for up to two hours and minimal rates of rates of psychoperceptual adverse effects.