◊ SUMMARY:
The number of publications on the peri-operative use of auricular acupuncture has rapidly increased within the last decade. The aim was to evaluate clinical evidence on the efficacy of auricular acupuncture for postoperative pain control. Electronic databases: Medline, MedPilot, DARE, Clinical Resource, Scopus and Biological Abstracts were searched from their inception to September 2007. All randomised clinical trials on the treatment of postoperative pain with auricular acupuncture were considered and their quality was evaluated using the Jadad scale. Pain intensity and analgesic requirements were defined as the primary outcome measures. Of 23 articles, nine fulfilled the inclusion criteria. Meta-analytic approach was not possible because of the heterogeneity of the primary studies. In eight of the trials, auricular acupuncture was superior to control conditions. Seven randomised clinical trials scored three or more points on the Jadad scale but none of them reached the maximum of 5 points. The evidence that auricular acupuncture reduces postoperative pain is promising but not compelling.
◊ Reviewed by H. Wulf, MD, PhD
Professor and Chairman, Department of Anaesthesiology and Intensive Care Medicine
University Hospital Marburg, Marburg, The Netherlands
Systematic reviews are a valuable tool to develop standards of care in modern medicine. Best results are obtained if a meta-analysis approach is chosen. The review of Usichenko et al. on auricular acupuncture to treat postoperative pain shows that this is not without problems. Only a (less reliable) systematic review could be performed since a meta-analysis was not possible due to the heterogeneity of methods and endpoints:
- Only 9 out of 23 studies were of sufficient quality to be included in the analysis (randomized controlled trials, RCTs). Even with some of these RCTs there were significant problems such as small sample sizes, inadequate control of non-specific effects, or deblinding. Sham acupuncture as a control and therapist blinding were rarely used.
- Endpoints were sometimes “pain intensity”, sometimes “no-opioid consumption”, and sometimes “opioid requirement”.
- Various acupuncture points at the ear were used.
- Some studies used electro-acupuncture whereas others used conventional methods.
- Independent study replications are missing. The majority of data originates from two research groups.
- Publication bias: A small study poorly powered but showing (by chance) a significant effect will be published, while a larger study without significant difference will not be submitted (because the investigator is disappointed) or rejected.
In summary, the evidence that acupuncture reduces postoperative pain is not compelling. The good news is that it will harm only in rare cases, while our standard therapy is frequently limited by side effects.
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