Effects of electrical cervical spinal cord stimulation on cerebral blood perfusion, cerebrospinal fluid catecholamine levels, and oxidative stress in comatose patients.

OBJECTIVES Electrical spinal cord stimulation (SCS) is used to treat of chronic pain, obstructive arterial-related ischemia, and anginal pain. This study investigated cerebral blood perfusion, cerebrospinal fluid (CSF) catecholamine levels, and oxidative stress before and after cervical SCS in comatose patients. METHODS We evaluated cerebral blood perfusion, catecholamine (dopamine, norepinephrine, and epinephrine) levels, and oxidative stress in 20 comatose patients before and after SCS. After SCS for six months, cerebral blood perfusion (SPECT index, 2.293 +/- 0.255 vs. 2.779 +/- 0.209, p < 0.001), dopamine (49.0 +/- 12.1 vs. 198.9 +/- 62.6, p = 0.025), and norepinephrine (197.6 +/- 62.9 vs. 379.6 +/- 52.6, p = 0.021) but not epinephrine were significantly increased. Moreover, superoxide free radicals in whole blood were significantly decreased (210,079 +/- 47,763 vs. 109,212 +/- 20,086, p = 0.011) after SCS. Nine patients recovered from the consciousness within 71-287 days. CONCLUSIONS Increase of cerebral blood perfusion and catecholamines (dopamine and norepinephrine) in CSF after SCS was observed, whereas epinephrine level was unchanged. The superoxide free radicals were decreased after SCS. The results suggest that SCS increases cerebral blood perfusion, attenuates oxidative stress and increases biogenic amines in comatose patients.