Addition of Fentanyl to Ropivacaine Infusion in Continuous Thoracic Paravertebral Infusion Does Not Improve Its Analgesic Effect Following Modified Radical Mastectomy: A Randomized Controlled Trial

A randomized controlled trial was conducted to evaluate pain scores in patients given continuous thoracic paravertebral (TPV) block with ropivacaine alone or with fentanyl in modified radical mastectomy (MRM). Forty female patients ASA classes 1 and 2, aged 18 to 60 years, undergoing MRM were recruited. Preanesthesia with 0.5% ropivacaine, 20 mL, was injected at the T4 TPV space. After 2 hours, patients were randomly assigned to receive a 0.1 mL/kg/h infusion of either 0.2% ropivacaine (group R) or 0.19% ropivacaine plus fentanyl, 2 jg/mL (group RF). Postoperatively, patient-controlled analgesia (PCA) with fentanyl was provided. Visual analog scale (VAS) pain scores at rest and movement were significantly less in group RF at 8 AM on postoperative day 1 (R vs RF: rest: 2 [interquartile range, 0-7] vs 1 [0-6]; P = .016; movement: 2.5 [1-8] vs 2 [1-8], P= .042) and on movement 60 minutes postoperatively (R vs RF: 2 [0-9] vs 2 [1-2]; P = .01). Mean total fentanyl consumed via PCA in group R was significantly more (206 ± 31.68 ¡jg vs RF 82.5 ± 35.07 ¡jg, P < .001). Mean total fentanyl consumed via PCA plus TPV infusion was comparable (R: 206 ± 31.68 jg vs RF: 211 ± 25.52 µg, P < .2). Because the mean VAS score was below 3 in all timeframes, addition of fentanyl to ropivacaine in continuous TPV infusion in MRM had no clinical advantage.