Postoperative nausea and vomiting (PONV) are common problems in patients undergoing breast surgery or with intravenous patient-controlled analgesia (IV PCA). We evaluated the effect of ondansetron or dolasetron for the prevention of PONV in patients undergoing a mastectomy with IV PCA.

A total of 126 patients were randomly divided into three groups. The PCA group was a control group. For the PCAO group (IV PCA mixed with ondanseron), 4 mg ondansetron was intravenously injected 30 min before the end of surgery and 8 mg was mixed in IV PCA. For the PCAD group (IV PCA mixed with dolasetron), 10 mg dolasetron and 20 mg was administered as same manner with the PCAO group. The incidence of PONV, the need for rescue antiemetics, adverse events, and the nausea and vomiting severity score were analyzed for 1 hour and 24 hours postoperative periods.

During the first 24 hours postoperatively, the incidence of PONV was 76.2% for the PCA group, 70.7% for the PCAO group (P > 0.05 versus the PCA group) and 66.7% for the PCAD group (P > 0.05 versus the PCA group), respectively. The incidence of need for rescue antiemetics was 40.5% for the PCA group, 9.5% for the PCAO group (P < 0.05 versus the PCA group) and 4.8% for the PCAD group (P < 0.05 versus the PCA group), respectively.

In the patients receiving IV PCA after a mastectomy, ondansetron or dolasetron were not effective for the reduction of the incidence of PONV. However, the need for rescue antiemetics was significantly decreased.