Objective: To evaluate the efficacy of multimodal antiemetic management on PONV prevention in patients undergoing ambulatory gynecologic endoscopic surgery.

Material and Method: The study was a randomized double blind control trial conducted in Songklanagarind hospital. 340 patients, undergoing ambulatory gynecologic endoscopic surgeries, were enrolled into the study. All patients were randomized to receive conventional management (The control group), or multimodal antiemetic management (The multimodal group) under volatile-based general anesthesia. Patients in the control group received thiopental induction and used nitrous oxide for maintenance of anesthesia. Whilst, patients in the multimodal group received propofol induction without the use of nitrous oxide. Patients were then classified into risk levels, according to the risk factors of PONV using a simplified risk score and administered antiemetic according to the protocol: The multimodal group received ondansetron±dexamethasone±dimenhydrinate prophylaxis, while the control group received no drugs, or only an ondansetron prophylaxis. This was dependant on the patients risk level. The incidence of nausea, emesis and antiemetic requirements were recorded at recovery room. The severity score of PONV was collected every 30 minutes up until 180 minutes and then again at 24 hours after surgery by telephone call.

Results: 166 patients (The control group) along with 162 patients (The multimodal group) underwent analysis. There were no statistically significant differences between the two groups in concerns to; age, weight, history of PONV, type of surgery, duration of anesthesia, and opioids usage. Patients in the control group had a higher incidence of nausea than those in the multimodal group significantly at PACU (16.9% vs 8.0%, p = 0.02), and at 24 hours (16.3% vs 5.6%, p<0.01). Those in the control group also had more severe degrees of PONV than those within the multimodal group significantly at 30, 60 and 120 min in PACU (p = 0.01, 0.03 and 0.04, respectively) and at 24 hours (p<0.01). Moreover, the control group required antiemetic treatment during PACU stays which was higher than those patients in the multimodal group significantly (19.9% vs 6.8%, p<0.001).

Conclusion: Multimodal antiemetic management is more effective on the prevention of PONV in terms of reducing incidence of nausea, degree of PONV and rescued antiemetic requirements during PACU as well as at 24 hours, than those receiving no intervention, or the single drug prophylaxis in patients undergoing ambulatory gynecologic endoscopic surgery.

Keywords: multimodal antiemetics management, postoperative nausea and vomiting, ambulatory, endoscopic surgery