In this case report, we describe the effect of
ketamine infusion in a case of severe refractory
complex regional pain syndrome I (CRPS I). The patient was initially diagnosed with CRPS I in her right upper extremity. Over the next 6 years, CRPS was consecutively diagnosed in her thoracic region, left upper extremity, and both lower extremities. The severity of her
pain, combined with the extensive areas afflicted by CRPS, caused traumatic emotional problems for this patient. Conventional treatments, including
anticonvulsants,
bisphosphonates, oral
steroids and
opioids, topical creams, dorsal column spinal
cord stimulation, spinal morphine infusion, sympathetic ganglion block, and
sympathectomy, failed to provide long-term relief from
pain. An
N-methyl-d-aspartate (
NMDA) antagonist inhibitor,
ketamine, was recently suggested to be effective at resolving
intractable pain. The patient was then given several infusions of intravenous
ketamine. After the third infusion, the
edema, discoloration, and temperature of the affected areas normalized. The patient became completely
pain-free. At one-year of follow-up, the patient reported that she has not experienced any
pain since the last
ketamine infusion. Treatment with intravenous
ketamine appeared to be effective in completely resolving
intractable pain caused by severe refractory CRPS I. Future research on this treatment is needed.