Evaluation of analgesic efficacy of intra-articular bupivacaine, bupivacaine plus fentanyl, and bupivacaine plus tramadol after arthroscopic knee surgery

Abstract

Purpose: To compare the efficacy of intra-articular (IA) bupivacaine, bupivacaine-fentanyl, and bupivacaine-tramadol for relief of postoperative pain after arthroscopic knee surgery.

Methods: In a randomized double-blind design, 60 adult American Society of Anesthesiologists class I or class II patients undergoing elective arthroscopic knee surgery under general anesthesia were randomized to 3 groups: all received 30 mL of 0.25% bupivacaine, plus either 1 mL of normal saline solution (group I), 1 mL (50 μg) of fentanyl (group II), or 1 mL (50 mg) of tramadol (group III). Pain was assessed by use of a 100-mm visual analog scale (VAS) at 0, 1, 2, 4, 6, and 8 hours postoperatively. Intramuscular diclofenac sodium was used as rescue analgesic. Postoperative adverse effects were noted.

Results: The mean VAS pain scores were the lowest for group II, intermediate for group III, and highest for group I. There was a significant main effect for group differences on pain scores (F = 41.138, P < .001). The main effect for the time factor was also significant (F = 6.097, P < .001). However, both group II and group III were comparable and both were superior to group I with regard to supplementary analgesia in terms of (1) number of patients receiving it, (2) total consumption during the study period, and (3) time to first supplementary analgesic requirement. The incidence of adverse event was comparable among the 3 groups.

Conclusions: On the primary outcome measure (VAS pain score), both bupivacaine with fentanyl and bupivacaine with tramadol were better than IA bupivacaine, and bupivacaine with fentanyl was better than that with tramadol. However, both the combinations were comparable to each other with regard to the secondary outcome measure (supplementary analgesic requirement). Thus IA bupivacaine-fentanyl appears to be the best combination for relief of postoperative pain in patients undergoing arthroscopic knee surgery, followed by IA bupivacaine-tramadol.

Level of evidence: Level I, randomized controlled trial.