Objective:To study the effects of different doses of Dextromethorphan Hydrobromide combining with tramadol for postoperative analgesia on serum markers.Methods:80patients received abdominal surgery in our hospital were retrospectively studied,including 40 cases in observation group received 20 mg Dextromethorphan Hydrobromide combined with tramadol for analgesia,and 40 cases in control group received 10 mg Dextromethorphan Hydrobromide combined with tramadol for analgesia.Then serum were collected and pain ...