Prevention of PONV with dexamethasone in female patients undergoing desflurane anesthesia for thyroidectomy

Desflurane is associated with a higher incidence of 24-h postoperative nausea and vomiting (PONV) as compared with sevoflurane or isoflurane. Dexamethasone 5 mg i.v. is suggested to be the minimum effective dose for prophylaxis of PONV in women undergoing thyroidectomy with isoflurane anesthesia. The objective of this study was to investigate whether a 5 mg dose of dexamethasone could be enough for, or a larger dose at 8 mg, could be more capable of preventing PONV in women undergoing desflurane anesthesia for thyroidectomy.

One hundred and thirty five patients were assigned to receive one of three treatment regimens prior to induction i.e., dexamethasone 8 mg i.v. (Group D8), dexamethesone 5 mg i.v. (Group D5) or saline (Group S).

It was demonstrated that the prophylactic administration of either dexamethasone 8 mg or 5 mg significantly reduced the overall incidence of PONV in patients undergoing thyroidectomy with desflurane anesthesia (P < 0.001, Group D8 vs. Group S; Group D5 vs. Group S). However, patients who received dexamethasone 8 mg showed a higher incidence of complete responses (no vomiting or need of rescue antiemetic medication for a 24-h postoperative period) in comparison with those receiving dexamethasone 5 mg (86% vs. 67%; P < 0.01).

The results of this study showed that in PONV prophylaxis, in female patients undergoing desflurane anesthesia for thyroidectomy, the effect of dexamethasone 8 mg was superior to that of dexamethasone 5 mg.