Betamethasone in prevention of postoperative nausea and vomiting following breast surgery.

STUDY OBJECTIVE To investigate whether betamethasone decreases the incidence of postoperative nausea/vomiting (PONV) and reduces postoperative pain following partial mastectomy. DESIGN Prospective randomized, double-blinded study. SETTING Operating room and Postanesthesia Care Unit of a university hospital. PATIENTS 80 ASA physical status 1 and 2 women scheduled for elective breast cancer surgery. INTERVENTIONS Patients were randomly allocated to two groups in double-blinded fashion: Group B (betamethasone; 37 pts) and Group C (control; 38 pts). Group B received 8 mg of betamethasone intravenously before the start of surgery. MEASUREMENTS The rate of PONV and pain were recorded using a numeric rating scale (NRS; 0-10), as well as rescue doses of antiemetics (ondansetron) and analgesics (ketobemidone). MAIN RESULTS There was a significant lower incidence of postoperative nausea (PON) scoring NRS ≥ 1 in Group B in the 4 to 12-hour period compared with Group C (P = 0.02). The cumulative incidence of PON was 57% in Group B versus 68% in Group C (P = 0.27). The overall incidence of postoperative vomiting (POV) was 18% and 20% in Groups B and C, respectively. Postoperative pain was reduced by 40% in Group B in the 4 to 12-hour period, but the mean dose of postoperative rescue analgesic did not differ between the groups. CONCLUSIONS Preoperative betamethasone reduces the severity of PONV and pain in patients undergoing elective breast surgery.