Clinical study of analgesic effect of tramadol combined with low-dose morphine or fentanyl on postoperative patient-controlled epidural analgesia

Objective To study the analgesic effect for postoperative patient-controlled epidural analgesia (PCEA) of tramadol combined with low-dose morphine or fentanyl. Methods One hundred twenty patients (ASA statusⅠ-Ⅱ) undergoing abdominal operation with PCEA were randomly allocated to three groups, forty for each. The analgesic solutions were 0. 6% tramadol in Group T, 0. 4% tramadol and 0. 004% morphine in Group TM 0. 4 % tramadol and 0. 000 4% fentanyl in Group TF. The same LCP parameters were used in continuous infusion of 2 mL/h and a bolus dose of 1 mL with a lockout interval of 20 min. Results In the early analgesic time (4,8 and 24 h), the VAS scores of Group TM and Group TF were lower than that of Group T with no significant differences in the analgesic end point (48 h). The number of PCEA demanded and total dose of Group T were higher than those of Group TM and Group TF. Lower incidence of side effects such as nausea and vomiting occurred in Group TF. Comparing to Group T and Group TM, Group TF patients received the highest Global Satisfaction Score (GSS). Conclusion Tramadol combined with low-dose morphine or fentanyl produces good quality of pain relief than tramadol alone, especially in the early analgesic stage. Tramadol combined with low-dose fentanyl was considered as a satisfactory method for PCEA with reliable analgesia and low incidence of side effects. (Shanghai Med J, 2006, 29:718-720)