Anesthesia for a child with Camurati–Engelmann disease

SIR—We have read with interest the article by Park Y et al. (1) that compared 6 lg kg 1 of ramosetron with 100 lg kg 1 of ondansetron in children after orthopedic surgery. They found ‘significantly less vomiting during the first 24-h and 6–24-h period after surgery in ramosetron group than in ondansetron group’ and concluded that ramosetron was more effective than ondansetron in preventing postoperative vomiting (POV) in children. One significant limitation of their study was that they studied only a single dose of ondansetron (i.e., 100 lg kg ) and did not examine the dose–response relationship. In adults, a previous randomized controlled trial by Ryu J et al. (2). comparing 0.3 mg of ramosetron, 4 mg of ondansetron, and 8 mg of ondansetron revealed that 4 mg of ondansetron was less effective than 0.3 mg of ramosetron but 8 mg of ondansetron was as effective as a prophylaxis of postoperative nausea and vomiting (PONV). Therefore, when comparing ramosetron with ondansetron, it is important to consider the dosage. Park Y et al. (1). referred the FDA alert about QT interval prolongation with high-dose ondansetron (3), which states that the use of a single 32 mg intravenous dose of ondansetron in adults should be avoided. The dose of 32 mg is equal to that of 400–500 lg kg 1 for adult patient who weighs approximately 70 kg. Moreover, this FDA alert states that ‘ondansetron can continue to be used in adults and children with chemotherapy-induced nausea and vomiting at the lower intravenous dose recommended in the drug label, a dose of 0.15 mg kg 1 administered every 4 h for three doses’. Therefore, after carefully considering the FDA alert, 100 lg kg 1 of ondansetron is not considered the maximum dose, although it is a recommended dose for prevention of PONV. Taken together, it would be premature to conclude that ramosetron is more effective than ondansetron for preventing PONV in children because it is possible that higher but safe doses of ondansetron (e.g., 150 lg kg ) have a similar effect on PONV in children compared with ramosetron. Further studies are needed to determine which of the two drugs is more effective in preventing PONV in children.