This systematic review aims to review clinical studies on the use of
ketamine infusion for patients with treatment-resistant
complex regional pain syndrome (CRPS). The following systematic review was registered on the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42021228470). Studies for the systematic review were identified through three databases: PubMed, Cumulative Index of Nursing and Allied Health Literature (CINAHL), and Cochrane Reviews. Inclusion criteria for studies consisted of randomized clinical trials or cohort studies that conducted trials on the use of
ketamine infusion for
pain relief in patients with CRPS. Exclusion criteria for studies included any studies that were systematic reviews, meta-analyses, case reports, literature reviews, or animal studies. In the included studies, the primary outcome of interest was the post-
drug administration
pain score. In this systematic review, 14 studies met the inclusion criteria and were reviewed. In these studies, the dosage of
ketamine infusion used ranged from 0.15 mg/kg to 7 mg/kg with the primary indication being the treatment of CRPS. In 13 of the studies,
ketamine infusion resulted in a decrease in
pain scores and relief of symptoms. Patients who received
ketamine infusion for treatment-resistant CRPS self-reported adequate
pain relief with treatment. This suggests that
ketamine infusion may be a useful form of treatment for patients with no significant
pain relief with other conservative measures. Future large-scale studies, including randomized double-blind placebo-controlled trials on the use of
ketamine infusion for CRPS, must be conducted in a large-scale population to further assess the effectiveness of
ketamine infusion in these populations.