Effects of Preoperative Acupuncture on Prevention of Nausea and Vomiting and Plasma Serotonin Values in the Hysterectomy Postoperative Period: a Randomized Clinical Trial

Background: Nausea and vomiting are frequent complications of anesthesia in the postoperative period. Acupuncture at the pericardium point 6 (PC6) is known to be effective in preventing postoperative nausea and vomiting (PONV). Objectives: The objective of the present study is to investigate the effects of acupuncture performed at the PC6 point in the prevention of PONV in women undergoing elective open hysterectomy under general inhalational anesthesia and to assess its association with plasma serotonin levels. Methods: 97 patients undergoing elective open hysterectomy were randomly divided into two groups: acupuncture group (bilateral acupuncture at PC6, n = 49), and a control group (no acupuncture, n = 48). All patients prophylactically received ondansetron and dexamethasone and, as rescue medication, metoclopramide in case of occurrence of PONV. The primary outcome evaluated was occurrence of nausea and vomiting within 24 hours after surgery. Serotonin plasma levels were measured before and after acupuncture prior to anesthesia induction. For the control group, the repeat measurement was performed 30 minutes after admission to the preoperative unit. Results: Acupuncture at PC6 significantly reduced the incidence of nausea (29.2% vs. 6.1%; p < 0.003), and the need of rescue medication (metoclopramide) (33.3% vs. 10.2%; p < 0.006), but not vomiting (4.2 vs. 4.1; p < 0.98). The plasma serotonin levels between control and acupuncture groups did not differ. Conclusion: This study shows that acupuncture at PC6 resulted in a lower incidence of postoperative nausea in patients undergoing hysterectomy.