Effects of intensity of electroacupuncture upon experimental pain in healthy human volunteers: a randomized, double-blind, placebo-controlled study

Barlas, P.

Ting, S.L.

Chesterton, L.S.

Jones, P.W.

Sim, J.

Pain

2006

122(43467)

81-89

RCT

Healthy Subjects

Anesthesia and Analgesia

Pain

Rct

Acu Versus > 1 Control

Electroacupuncture

TCM Acupuncture Style

Fixed Acupuncture Protocol

Restricted Modalities, Acupuncture Only

No Treatment Control

Sham Control

Non Penetrating Sham, Mechanical

Non Penetrating Sham, Electrical

Verum Acupoint Control

Electroacupuncture is commonly used for pain relief. Despite an extensive evidence-base guiding the selection of stimulation parameters, little methodologically robust research exists regarding the level of intensity required to provide effective doses. This study investigated the hypoalgesic effects of two stimulation intensities compared to placebo on pressure pain thresholds (PPTs) in pain-free humans. Forty-eight acupuncture-naive volunteers (mean age 23), stratified by gender, were screened for relevant contraindications and randomly allocated to four groups: control, placebo, high-intensity ("to tolerance but sub-noxious") or low-intensity ("strong but comfortable"). True or placebo electroacupuncture, using the Streitberger placebo needle, was administered to acupoints on dominant forearm (LI10, TH5) and ipsilateral leg (GB34, ST38). True needles (30 mm long, 0.3 mm diameter) were inserted 20-25 mm and "de-qi" was elicited from active groups, prior to administering 30 min of 4 Hz, 200 micros electroacupuncture. No electrical stimulation was performed on control and placebo groups, and placebo needles were used. After the intervention period, all needles were removed. Volunteers were monitored for 30 further minutes. Two PPT measurements were taken bilaterally from muscle bellies of first dorsal interosseous by an independent rater, at baseline and at six subsequent 10-min intervals. Square-root transformed data were analysed using repeated-measures ANOVA, with baseline data as covariate. The high-intensity group was significantly different from the placebo group for both measurement sites (p=.020, p=.033). The control group displayed stable PPT readings over time. No significant differences were observed between the placebo and control groups. These findings suggest that high-intensity levels may be important in optimal dose selection.

Date of Input: 5/21/2015; Date Modified: 8/6/2015; Availability: --In File--; Priority: Normal; Anesthesia and Analgesia; School of Health and Rehabilitation, Keele University, Staffordshire ST5 5BG, UK.; eng; Web: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=16527396

Healthy Subjects

48

1 Day