Effects of acupressure, manual acupuncture and Laserneedle acupuncture on EEG bispectral index and spectral edge frequency in healthy volunteers.
OBJECTIVE
The main purpose of this study was to investigate the effects of sensory (acupressure and acupuncture) and optical stimulation (Laserneedle acupuncture) on electroencephalographic bispectral index, spectral edge frequency and a verbal sedation score.


METHODS
Twenty-five healthy volunteers (mean age +/- SD: 25.5 +/- 4.0yr) were investigated during the awake state. The acupuncture point Yintang and a placebo control point were stimulated. The study was performed as a randomized, controlled and partly blinded cross-over trial.


RESULTS
Bispectral index and spectral edge frequency values both decreased significantly (P < 0.001) during acupressure on Yintang to values of 62.9 (minimum 35) +/- 13.9 bispectral index and to 13.3 (minimum 2.9) +/- 8.1 Hz (spectral edge frequency right) and 13.8 (minimum 2.7) +/- 7.3 Hz (spectral edge frequency left), respectively. Bispectral index was also significantly (P < 0.05) affected by Laserneedle acupuncture and acupressure on the control point but the changes were not clinically relevant, 95.4 +/- 4 and 94.2 +/- 4.8, respectively. All interventions significantly (Yintang: P < 0.001; control point: P < 0.012) reduced verbal sedation score.


CONCLUSIONS
The study highlights the electroencephalographic similarities of acupressure induced sedation and general anaesthesia as assessed by bispectral index and spectral edge frequency.
Litscher
G
G
University of Graz, Department of Biomedical Engineering and Research in Anesthesia and Intensive Care, Graz, Austria. gerhard.litscher@uni-graz.at
D019050:Acupressure / Q000379:methods*; D026881:Acupuncture / Q000295:instrumentation / Q000379:methods*; D000328:Adult; D001794:Blood Pressure; D016292:Procedural Sedation; D018592:Cross-Over Studies; D004569:Electroencephalography / Q000187:drug effects*; D005260:Female; D006339:Heart Rate; D006801:Humans; D007834:Lasers; D008297:Male; D009339:Needles