Patients and Methods
We randomized 269 patients undergoing TKAs between February and December 2011 to receive either intravenous dexamethasone (dexamethasone; Yuhan, Seoul, Korea) once 1 hour before surgery with intravenous ramosetron (Nasea, Astellas, Tokyo, Japan) once immediately after surgery (Dexa-Ra group; as the experimental group, n = 135) or intravenous ramosetron alone once immediately after surgery (Ra group; the control group, n = 134). Eligible patients included those 18 years or older who were scheduled for unilateral TKA for primary osteoarthritis. Exclusion criteria included a history of intolerance or allergy to any drug used in the current study; severe impairment of bowel motility; administration of another antiemetic drug or systemic steroid 24 hours before surgery; history of cardiovascular or respiratory disease, or alcohol or opioid dependence; and impairment of renal or hepatic function.