P6 acustimulation reduced retching following laparoscopic fundoplication: Results of a randomized clinical effectiveness trial

Mark R Wendling, MD, Rebecca Dettorre, W. Scott Melvin, MD, Kyle A Perry, MD

The Ohio State University

Introduction: Post-operative nausea and vomiting (PONV) and retching are common side effects of surgery and anesthesia. Patients undergoing laparoscopic fundoplication represent a high-risk population. Standard therapy includes anti-emetic medication, but concern exists regarding their efficacy and side effect profiles. Transcutaneous stimulation of the P6 acupoint has been shown to effectively reduce nausea and vomiting due to motion sickness and pregnancy, as well as PONV. To date, no data exists regarding its effectiveness in patients undergoing laparoscopic fundoplication. In a prospective comparative effectiveness trial, we tested the hypothesis that 7 day P6 acustimulation in combination with medical therapy would reduce PONV and retching following laparoscopic fundoplication compared to medical therapy alone.

Methods: A single center, prospective, randomized study of 100 patients undergoing laparoscopic fundoplication was conducted between August 24, 2011 and August 24, 2012. Standard medical therapy included 24 hours of scheduled ondansetron and promethazine as needed. The experimental group received 7 days of P6 acustimulation immediately after surgery and standard medical therapy. All patients undergoing laparoscopic antireflux surgery, paraesophageal hernia repair, or Heller myotomy were assessed for inclusion. The primary outcome measure was incidence of PONV at 6 and 24 hours after surgery. Secondary outcomes included incidence of retching/emesis 6 hours after surgery, breakthrough anti-emetic use, and time to discharge from the post-anesthesia care unit. Results are reported as incidence (%), mean ± standard deviation or median (range). Statistical analysis was performed using the Student’s T-test for continuous variables, Mann-Whitney U test for ordinal variables, and Chi-squared for binary data with p<0.05 defined as statistical significant.

Results: 100 patients were enrolled in the study and randomized to either standard medical therapy (n=51) or P6 acustimulation plus standard medical therapy (n=49). The study groups did not differ in terms of age, gender, BMI, or operative time. In total 79 patients completed the study protocol. Three withdrew because they did not wish to continue to record symptoms, the remainder failed to return data after discharge. All patients tolerated the stimulator. Analysis was performed on an intention to treat basis. The study groups did not differ in either 6-hour (2.32±3.11 versus 2.68±3.22, p=0.267) or 24-hour (1.81±2.17 vs 2.03±2.83, p=0.464) PONV scores. Thirteen percent of patients in the P6 acustimulation group experienced retching within 6 hours after surgery compared to 30% of patients treated with standard medical therapy alone (p=0.045). There were no differences in time to recovery room discharge (137±85 min versus 132±70 min, p=0.798) and total breakthrough Phenergan use (42.0±75.6 mg versus 57.6±128.2 mg, p=0.234) between groups. There were no instances of early fundoplication failure or hiatal hernia recurrence in this series.

Conclusion: Patients undergoing laparoscopic fundoplication represent a population at high risk for complications related to PONV and retching. While it produces little effect on nausea and antiemetic medication use, P6 acustimulation is a useful adjunct to standard antiemetic therapy to reduce retching and stress on newly created fundoplications in the immediate post-operative period.

Session: Poster Presentation

Program Number: P245