Efficacy and safety of ketamine in the treatment of neuropathic pain: A
systematic review and meta-analysis of randomized controlled trials
Abstract
Neuropathic pain may develop after neuronal injury and distinguishes
itself from other painful conditions due to its unique clinical
characteristics and for being refractory to treatment with conventional
analgesics and non-steroidal anti-inflammatory drugs (NSAIDs).
N-methyl-D-aspartate receptors (NMDARs) are known for their relation to
neuroplasticity and play a role in neuropathic pain and opioid induced
hyperalgesia. Ketamine is a N-methyl-D-aspartate (NMDA) antagonist with
strong analgesic and anti-hyperalgesic properties and its addition to
the treatment of neuropathic pain may reduce pain intensity in the short
and long term and may improve overall quality of life. Therefore, a
systematic review and meta-analysis were performed to investigate the
addition of ketamine to the treatment of patients with neuropathic
pain.Methods: Randomized controlled trials (RCTs) investigating the
effect of ketamine on pre-defined outcomes including pain intensity at
several time points, multidimensional pain scales, quality of life,
mood, impact on interpersonal interaction, quality of sleep, impact on
general daily activities, impact on work, and adverse outcomes, such as
nausea and vomiting, and psychedelic effects were searched in the
following databases: MEDLINE, CENTRAL, LILACS and EMBASE, from inception
to April 2021. Reviewers independently screened potentially eligible
articles, extracted data and assessed the risk of bias among eligible
articles. We used the GRADE approach to rate the overall certainty of
the evidence for each outcome.