A systematic review has evaluated the efficacy of as an adjunctive treatment for acute postoperative pain management. American authors included 15 RCTs comparing acupuncture with sham control in their analysis. Opioid analgesic consumption, and postoperative pain intensity at 8 and 72h were significantly decreased in the acupuncture group compared with the control group. Acupuncture treatment was also associated with a lower incidence of opioid-related side-effects such as nausea, dizziness, sedation, pruritus and urinary retention.

Acupuncture and related techniques for postoperative pain: a systematic review of randomized controlled trials. Br J Anaesth. 2008 Aug;101(2):151-60.