PC6 injection enhanced the preventive effect against postoperative nausea of granisetron compared with intravenous injection in gynecological laparoscopic patients: a randomized controlled study

Background Moderate to severe postoperative nausea and vomiting significantly impedes recovery and is inadequately managed by current pharmacotherapy. This study investigates whether granisetron injection at the PC6 acupoint enhances prevention of postoperative moderate to severe postoperative nausea and vomiting compared to intravenous injection. Methods 244 participants undergoing elective gynecologic endoscopic surgery under general anesthesia were randomly assigned to PC6 granisetron group, IV granisetron group, PC6 saline group and control group. All patients receive 5 mg dexamethasone during anesthesia induction. At the end of surgery, 2 mg granisetron was injected at the PC6 acupoint in PC6 granisetron group, 2 mg granisetron was injected intravenously in IV granisetron group, 2 ml saline was injected at the PC6 acupoint in PC6 saline group, no additional measures to prevent postoperative nausea and vomiting in control group. Results The incidence of moderate-to-severe postoperative nausea in PC6 granisetron group was significantly lower than that in IV granisetron group, PC6 saline group and control group within 24 h after surgery. (14.8% [9/61] vs. 32.8% [20/61]; RR = 0.45, [95% CI: 0.22, 0.91]; P = 0.02 (14.8% [9/61] vs. 29.5% [18/61]; RR = 0.50 [95% CI: 0.24, 1.02]; P = 0.058, (14.8% [9/61] vs. 43.9% [25/57]; RR = 0.34 [95% CI: 0.17, 0.66]; P < 0.01.) These differences started from 2 h after surgery. There was no adverse events about PC6 acupoint injection was found. Conclusion Granisetron injection at the PC6 acupoint enhances prevention of moderate-to-severe postoperative nausea within 24 h after surgery in patients undergoing elective gynecologic laparoscopic surgery under general anesthesia. Clinical Trial Registration This study was registered at http://www.chictr.org.cn (ChiCTR2400085300).