Outpatient intravenous ketamine for the treatment of complex regional pain syndrome: A double-blind placebo controlled study

– The results of this study warrant a larger randomized placebo controlled trial using higher doses of ketamine and a longer follow–up period. Methods

• Randomized double–blind placebo controlled trial.
• Before treatment, after informed consent was obtained, each subject was randomized into a ketamine or a placebo infusion group.
• Study subjects were evaluated for at least 2 weeks prior to treatment and for 3 months following treatment.
• All subjects were infused intravenously with normal saline with or without ketamine for 4 h (25 ml/h) daily for 10 days. The maximum ketamine infusion rate was 0.35 mg/kg/h, not to exceed 25 mg/h over a 4 h period.
• Subjects in both the ketamine and placebo groups were administered clonidine and versed.

Results

• Intravenous ketamine administered in an outpatient setting resulted in statistically significant reductions in many pain parameters.
• Subjects in the placebo group demonstrated no treatment effect in any parameter.