An economic evaluation of bupivacaine plus fentanyl versus ropivacaine alone for patient-controlled epidural analgesia after total-knee replacement procedure: a double-blinded randomized study.

Objective: Total-knee replacement (TKR) surgery is one of the most painful orthopedic procedures after surgery. Opioid has been commonly combined with a local anesthetic to improve the quality of pain relief, but the treatment has opioid-related side effects. This study compared the cost effectiveness of patient-controlled epidural analgesia (PCEA) with 0.0625% bupivacaine plus fentanyl (BF) 3 microg/mL versus 0.15% ropivacaine alone (R) during the first 48 hours after TKR procedure.

Methods: This prospective randomized double-blinded study was performed on 70 patients who underwent unilateral TKR procedure and received either BF or R after surgery. Visual analog scale (VAS) pain score at rest and upon movement, side effects, and cost of treatment were compared.

Results: Overall pain at rest and upon movement between groups was not significantly different (P = 0.58, 95% CI = 4.4 to -7.8 and P = 0.8, 95% CI = 6.4 to -8.2, respectively). Patients in the BF group experienced more pruritus and had more vomiting episodes than those in the R group (P = .015), whereas no difference occurred in other side effects. Nevertheless, patient satisfaction with pain management was higher in the BF group compared with that in the R group. In addition, pain treatment with bupivacaine and fentanyl was 18% less costly compared with ropivacaine alone.

Conclusions: Considering the economic evaluation, we conclude that PCEA with 0.0625% bupivacaine plus fentanyl 3 microg/mL is more cost effective and provides more patient satisfaction than PCEA with ropivacaine alone. However, use of epidural ropivacaine alone causes fewer opioid-related side effects, particularly pruritus and vomiting.