The prophylactic effect of tropisetron on epidural morphine-related nausea and vomiting: a comparison of dexamethasone with saline.

Unlabelled: Tropisetron is a 5-hydroxytryptamine subtype 3 receptor antagonist that is primarily used in the prevention of chemotherapy-induced nausea and vomiting. We evaluated the prophylactic effect of tropisetron on postoperative nausea and vomiting associated with epidural morphine. Dexamethasone and saline served as controls. One-hundred twenty women (n = 40 in each of three groups) undergoing abdominal total hysterectomy under epidural anesthesia were enrolled in this randomized, double-blinded, and placebo-controlled study. At the end of surgery, Group 1 received IV tropisetron 5 mg, whereas Groups 2 and 3 received dexamethasone 5 mg and saline, respectively. We found that tropisetron did not significantly reduce the occurrence of nausea and vomiting associated with epidural morphine. Dexamethasone, however, reduced the total incidence of nausea and vomiting from 59% to 21% (P < 0.01) and the percentage of patients requiring rescue antiemetic from 38% to 13% (P < 0.05). We conclude that IV tropisetron 5 mg did not prevent the occurrence of postoperative nausea and vomiting associated with epidural morphine. IV dexamethasone 5 mg was effective for this purpose.
Implications: We compared the prophylactic IV administration of tropisetron 5 mg to prevent postoperative nausea and vomiting (PONV) associated with epidural morphine with dexamethasone 5 mg and saline in women undergoing hysterectomy. We found that tropisetron 5 mg did not significantly reduce the occurrence of PONV associated with epidural morphine. Dexamethasone 5 mg was effective for this purpose.