Perineal pruritus after the administration of iv dexamethasone.

To the Editor: We, too, have noticed the phenomenon described by Perron et al.1 after a bolus injection of dexamethasone 8 mg iv. Our strategy to prevent this is to administer the dexamethasone immediately after the induction of general anesthesia. However, this might limit the efficacy of dexamethasone to prevent postoperative nausea and vomiting (PONV). The article by Wang compares the administration of dexamethasone before induction and at the conclusion of the anesthetic.2 It does not take into account the administration of dexamethasone at any other time in the course of the anesthetic. This article is the only one which is quoted in the recent “Consensus guidelines for managing postoperative nausea and vomiting”3 with regard to the timing of the dose of dexamethasone. While Wang et al. conclude “the prophylactic iv administration of dexamethasone immediately before the induction, rather than at the end of anesthesia, was more effective in preventing PONV,” I suspect that our technique is as effective as administering the drug before induction while avoiding this unpleasant side effect. In Wang’s study, late (2 to 24 hr postoperatively) PONV was reduced similarly by the administration of dexamethasone at the beginning or at the end of anesthesia, suggesting that the drug remains effective despite a later administration. Future studies should determine whether delaying its administration by a couple of minutes truly limits its efficacy to prevent PONV.