فصلنامه علمی­ پژوهشی بیهوشی و درد

burning pain, allodynia and hyperalgesia, even after stopping the irritant factor. Opioid-induced

hyperalgesia and peripheral nerve injuries in lower extremities orthopedic surgeries can also

make the same symptoms, which sometimes make it difficult to diagnose it from causalgia (type

II complex regional pain syndrome). Post-traumatic neuralgia is not so common, often does not

respond well to usual medications and prolongs the patient’s stay in hospital. Noting the

anatomical and physiological aspects of pain transmission pathways and also role of pain

transmission inhibitors via NMDA receptors in pain management, opens us a new window to the

role of medicines such as ketamine in prevention and treatment of neuropathic or chronic postoperative

pains. We report a case involving refractory neuropathic pain which is eventually

controlled with low dose of ketamine.