Comparison of ultrasound guided transversus abdominis plane block with different concentrations of ropivacaine combined with fentanyl: a randomized double-blind trial

Objectives: This study was conducted to assess the duration of analgesia using different concentrations of ropivacaine (0.2%, 0.375% and 0.5%) combined with fentanyl in Transversus Abdominis Plane (TAP) block. In addition to analgesic effects, hemodynamic effects, sedation and side effects were also evaluated in this study. Methodology: A total of 90 patients scheduled for elective total abdominal hysterectomy (TAH) surgery under spinal anesthesia were randomly allocated to one of the three groups: R1 group received - 29 mL 0.2% ropivacaine combined with 50 μg fentanyl (1 mL) to make a total of 30 mL in TAP block; R2 - 29 mL 0.375% ropivacaine combined with 50 µg fentanyl (1 mL) to make a total of 30 mL; and group R3 - 29 mL 0.5% ropivacaine combined with 50 µg fentanyl (1 mL) to make a total of 30 mL. With the help of visual analogue scale (VAS) duration of analgesia was assessed also total rescue analgesic requirement was recorded. Results: Duration of analgesia was significantly increased in group R3 (410.52 ± 70.18 min vs. 353.17 ± 92.03 min vs. 309.28 ± 83.66 min; [R3 vs. R2 vs. R1 respectively (P > 0.05)]. Significantly fewer patients in the R3 group required rescue analgesia. (23.3% vs. 36.6% vs. 63.3%; [R3 vs. R2 vs. R1 respectively (P > 0.05)]. Conclusion: We conclude that higher concentration of ropivacaine provided prolonged analgesia compared to lower concentrations in TAP block. However, 0.2% ropivacaine provides statistically similar postoperative analgesia to 0.375% ropivacaine. Abbreviations: ASA - American Society of Anesthesiologists; LAST - local anesthetic systemic toxicity; PONV - post-anesthesia care unit; RSS - Ramsey sedation scale; TAP block - Transversus Abdominis Plane block; TAH - total abdominal hysterectomy; Keywords: Anesthesia, ropivacaine, spinal cord, fentanyl, hysterectomy. Citation: Nallam SR, Darsi A, Veeramalla P, Sunkesula A, Chiruvella S. Comparison of ultrasound guided transversus abdominis plane block with different concentrations of ropivacaine combined with fentanyl: a randomized double-blind trial. Anaesth. pain intensive care 2024;28(6):1043-1049. DOI: 10.35975/apic.v28i6.2613 Received: August 20, 2024; Reviewed: October 16, 2021; Accepted: October 18, 2024