Prospective Placebo-controlled Randomized Trial to compare the Efficacy of Ketamine as an Adjuvant to Epidural Steroids in preventing Repeat Blocks in Chronic Low Back Pain

ABSTRACT Introduction Low back pain behaves as a “silent epidemic,” ranking first among complications related to work. Often there is a large gap between a patient's desired pain reduction and the minimum percentage of improvement that would make a treatment worthwhile. Consequently, debate continues as to the value of epidural steroid injections, supremacy of one adjuvant over others, various doses, and concentrations in optimizing pain management. Objective To compare the efficacy of ketamine vs normal saline as an adjuvant to epidural steroids in chronic low back pain. Study design Randomized prospective placebo-controlled study. Materials and methods The study was conducted on 60 patients of age group 18 to 70 years having chronic lower backache with or without radiculitis of minimum 3 months duration and having no relief with conventional treatment. The patients selected were randomly allocated into two groups of 30 patients each: Group I (n = 30) given triamcinolone 40 mg, preservative-free ketamine 30 mg (0.6 mL) made up to 6 mL solution with 0.25% bupivacaine and group II (n = 30) given 0.6 mL normal saline instead of ketamine. Outcome measures The primary outcome measured was number of patients requiring repeat blocks and number of repeat blocks administered in 3 months. Other outcome measures were functional improvement quantified by visual analog scale (VAS) and Oswestry disability index (ODI) as well as improvement in psychological status by depression scoring, all taken at 2 weeks interval for 3 months. The periprocedural complications were also noted at the end of the study. Results In managing lumbar radicular pain with lumbar epidural steroid injection (LESI), ketamine's role as an adjuvant proved to be advantageous for long-term relief by its inhibition of dorsal horn “wind up” phenomenon through N-methyl-D-aspartate (NMDA) receptor antagonism, thus reducing frequency of repeat blocks in group II (ketamine). Conclusion Thus to conclude, ketamine's advantage as a drug that prolongs pain relief from LESI is an avenue for further research and promises a bright future in the field of interventional pain medicine. How to cite this article Gupta R, Bawa C, Singh S, Mahajan L, Kaur B, Kaur T. Prospective Placebo-controlled Randomized Trial to compare the Efficacy of Ketamine as an Adjuvant to Epidural Steroids in preventing Repeat Blocks in Chronic Low Back Pain. Curr Trends Diagn Treat 2017;1(1):15-21.