Dexamethasone Palmitate for PONV After Open Surgery

Patients in the dexamethasone palmitate group will be assigned to receive intravenous injection of dexamethasone palmitate 8 mg (contains 5mg dexamethasone) after anesthesia induction and before surgical incision.

Patients in the dexamethasone group will be assigned to receive intravenous injections of dexamethasone 5 mg after anesthesia induction and before surgical incision.