<prompt> The following are used for treatment of postoperative nausea and vomiting following squint surgery in children except:-PropofolKetamineDexamethasoneOndansetron  <response>: ketamine does not have antiemetic effect, among anaesthetic agent propofol has antiemetic effect. even benzodiazepine has antiemetic effect , midazolam has best antiemetic effect among them. 