Study Status: Completed
Recruit Status: Unknown status
Study Type: Interventional
Official Title: Perioperative Opioid-induced Hyperalgesia and Its Prevention With Ketamine and Methadone
Brief Summary: Background: In perioperative period inhibition of N-Methyl-D-Aspartate receptor prevents opioid-induced hyperalgesia and reduce postoperative opioid requirement after abdominal surgery. Methadone is both a µ-opioid receptor agonist like Morphine and a N-Methyl-D-Aspartate antagonist. Study Aim. To evaluate the efficacy of intraoperative Ketamine and postoperative Methadone analgesia in preventing opioid-induced hyperalgesia after abdominal surgery.