• History of PONV
• Age (older than 3 yrs)
• Anesthetic (inhalation anesthetics)
• Opioids
• Perioperative oral fluid ingestion
• Type and duration (>30 min) of surgery
  Inguinal/orchidopexy
  Tonsillectomy and adenoidectomy
  Strabismus and middle ear surgery

PONV = postoperative nausea and vomiting.