Optimization of anesthesia antiemetic measures versus combination therapy using dexamethasone or ondansetron for the prevention of postoperative nausea and vomiting.

BACKGROUND: More than half of the patients undergoing laparoscopic cholecystectomy experience postoperative nausea and vomiting (PONV). This condition is related to the surgical, anesthetic, and patient factors. Volatile anesthetics, nitrous oxide, and opioids are known anesthetic risk factors for PONV, and thus preventive measures are justified. Propofol-based total intravenous anesthesia (TIVA), ondansetron, and dexamethasone each are reported to reduce PONV by approximately 30%. Avoiding or reducing perioperative narcotic analgesics, use of an 80% oxygen concentration, and proper intravenous fluid administration also reduce PONV. The anesthetic antiemetic measures have been studied separately. This study aimed to test the efficacy of these anesthetic antiemetic measures collectively with or without ondansetron or dexamethasone in preventing PONV among patients undergoing laparoscopic cholecystectomy. METHODS: For this study, 160 patients undergoing laparoscopic cholycestectomy (33 males and 147 females) were randomized into one of three groups. Group O received 4 mg of ondansetron; group D received 8 mg of dexamethasone; and group P received normal saline immediately after induction of anesthesia. All the patients received propofol-based TIVA, 80% oxygen concentration, 20 ml/kg of Hartman's solution, and 1.5 mg/kg of tramadol. Opioids, nitrous oxide, and volatile anesthetics were not used for any patient. Episodes of PONV were recorded at 0- to 4-h and 4- to 24-h intervals. RESULTS: The incidences of PONV were 32% in the ondansetron group, 30% in the dexamethasone group, and 33% in the saline group. There were no significant differences among the groups (p > 0.05). CONCLUSION: Ondansetron or dexamethasone added to collective anesthetic antiemetic measures does not further decrease the incidence of PONV after laparoscopic cholycestectomy.