抄録
Objective. To study the effect of ketamine on post-stroke pain, a drug challenge test was performed and the effects of a low-dose drip infusion of ketamine were examined in post-stroke pain patients.
Methods. In the drug challenge test, 5 mg of ketamine hydrochloride (i.v.) was given every 5 min up to a total of 25 mg in 120 post-stroke pain patients, and the pain reduction rate was assessed using a visual analogue scale (VAS). On the basis of the results of the drug challenge test, the effects of a low-dose ketamine drip infusion (LDKDI) were examined in 55 ketamine-sensitive post-stroke pain patients. For the LDKDI, 20 mg of ketamine hydrochloride added to 100 ml of saline was administered intravenously by 1-hour drip infusion.
Results. Fifty-five (45.8%) of 120 patients were evaluated as ketamine-sensitive with regard to their spontaneous pain. All of the 55 ketamine-sensitive patients treated with LDKDI could clearly experience pain reduction. The duration in which patients experienced pain reduction caused by LDKDI ranged from 1 to 6 hours in 27 patients (49%) and experienced in 38 patients (69.0%) up to 24 hours. In contrast, 17 (31%) of 55 patients experienced pain reduction lasting over 24 hours, and 4 (7.2%) of the 55 patients experienced pain reduction lasting about 1 week. In addition, 52 (94.5%) of the 55 patients were satisfied and expressed a desire to continue the LDKDI.
Conclusions. About half of the post-stroke pain patients were ketamine-sensitive, and LDKDI is useful for the treatment of post-stroke pain if candidates are selected on the basis of the results of a drug challenge test of ketamine.
