Comparison of Palonosetron and Ramosetron for Preventing Patient-controlled Analgesia Related Nausea and Vomiting Following Spine Surgery; Association With ABCB1 Polymorphism

Opioid-based intravenous patient-controlled analgesia (IV-PCA) offers excellent pain control, however, its use inevitably increases the incidence of postoperative nausea and vomiting (PONV). Ramosetron and palonosetron are commonly used 5-HT3 antagonists for the prevention and treatment of PONV. It is not clear which one has superior antiemetic efficacy for the prevention of PONV in patients using opioid-based IV-PCA. The antiemetic efficacy of 5HT3 antagonists may be influenced by polymorphism of ABCB1, a drug-transporter gene. This study evaluates relative antiemetic efficacy of ramosetron and palonosetron in patients using IV-PCA after spinal surgery and impact of ABCB1 polymorphism on the antiemetic efficacy of the ramosetron and palonosetron. The incidence and intensity of PONV during postoperative 48 h will be assessed. ABCB1 polymorphisms 3435C\>T and 2677G\>T/A will be evaluated in all patients.