European Journal of Anaesthesiology

Original Article

Effects of acupressure, manual acupuncture and Laserneedle® acupuncture on EEG bispectral index and spectral edge frequency in healthy volunteers

G. Litscher a1c1
a1 University of Graz, Department of Biomedical Engineering and Research in Anesthesia and Intensive Care, Graz, Austria

Article author query
litscher g   [PubMed][Google Scholar] 


Background and 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 ± 4.0 yr) 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.

(Accepted August 2003)

Key Words: ACUPRESSURE; ACUPUNCTURE; ELECTROENCEPHALOGRAPHY, bispectral index, spectral edge frequency.

c1 Correspondence to: Gerhard Litscher, Department of Biomedical Engineering and Research in Anesthesia and Intensive Care, University of Graz, Auenbruggerplatz 29, A-8036 Graz, Austria. E-mail:; Tel: +43 316 385 3907/83907; Fax: +43 316 385 3908