Acupuncture decreases somatosensory evoked potential amplitudes to noxious stimuli in anesthetized volunteers.

UNLABELLED: The effect of acupuncture on pain perception is controversial. Because late amplitudes of somatosensory evoked potentials (SEPs) to noxious stimuli are thought to correlate with the subjective experience of pain intensity, we designed this study to detect changes of these SEPs before and after acupuncture in a double-blinded fashion. Sixteen volunteers were anesthetized by propofol and exposed to painful electric stimuli to the right forefinger. Then, blinded to the research team, the acupuncture group (n = 8) was treated with electric needle acupuncture over 15 min at analgesic points of the leg, whereas the sham group (n = 8) received no treatment. Thereafter, nociceptive stimulation was repeated. SEPs were recorded during each noxious stimulation from the vertex Cz, and latencies and amplitudes of the N150 and P260 components were analyzed by analysis of variance. P260 amplitudes decreased from 4.40 +/- 2.76 microV (mean +/- SD) before treatment to 1.67 +/- 1.21 microV after treatment (P < 0.05), whereas amplitudes of the sham group remained unchanged (2.64 +/- 0.94 microV before versus 2.54 +/- 1.54 microV after treatment). In conclusion, this double-blinded study demonstrated that electric needle acupuncture, as compared with sham treatment, significantly decreased the magnitudes of late SEP amplitudes with electrical noxious stimulation in anesthetized subjects, suggesting a specific analgesic effect of acupuncture. IMPLICATIONS: This double-blinded study demonstrates that electric needle acupuncture, as compared with sham treatment, significantly decreases the magnitudes of late somatosensory evoked potential amplitudes with electrical noxious stimulation in anesthetized subjects, suggesting a specific analgesic effect of acupuncture.

Thyroid hormone response to moderate hypothermia in severe brain injury.

OBJECTIVE: To examine the effect of controlled moderate hypothermia on thyroid response in head-injured patients. DESIGN: Prospective, controlled, randomized study. SETTING: University hospital intensive care unit (ICU). PATIENTS: Twenty-eight patients with severe blunt head injury (Glasgow Coma Scale < or =9). INTERVENTION: Patients were randomly assigned to a hypothermia or a normothermia group. Hypothermia (32-33 degrees C) was induced within 8 h after trauma and maintained for a mean of 36 h. All patients were sedated and mechanically ventilated. MEASUREMENTS AND RESULTS: Thyroid-stimulating hormone( TSH), free and total triiodothyronine (FT3/TT3), reverse triiodothyronine (RT3) and thyroxine (FT4/TT4) were measured during the hypothermia or corresponding normothermia period, after regaining normothermia and 4-6 days later. Of 28 patients included in the study, 11 subjects were treated with hypothermia and 13 patients with normothermia. Four patients had to be excluded. In both groups, serum concentrations of TT3 and FT3 were just below the lower normal range whereas RT3 serum concentrations were near the upper limit of the normal range. TSH serum concentrations were not increased. No statistically significant intra- or inter-group differences were observed. CONCLUSIONS: Thyroid hormone patterns during moderate hypothermia in head-injured patients did not differ from the well known "low T3 state" which is observed in other forms of severe illness.