Ultrasound-guided femoral block in patients undergoing radiofrequency ablation of incompetent saphenous veins: A randomized controlled trial

Objective: To evaluate the benefit of ultrasound-guided femoral nerve block (UGFN) for reducing pain in patients undergoing radiofrequency ablation (RFA).Methods: Patients age 18-70 years scheduled for RFA were prospectively enrolled. Patients were randomly assigned to the UGFN or control group at a 1:1 ratio, and stratified according to concomitant phlebectomy procedure. The pain score and amount of fentanyl use during the operation were recorded. Pain severity and quadriceps muscle strength were recorded at 2-, 6-, and 12-hours postoperation.Results: Twenty-four patients in each group were included. Moderate to severe pain during surgery was found in 16 (66.7%) patients in the control group, and in 2 (8.3%) patients in the UGFN group (p < 0.001). Fentanyl use during surgery was significantly higher in controls than in UGFN patients (107.29 +/- 40.70 mg vs. 42.71 +/- 26.04 mg, respectively; p < 0.0001). The postoperative pain score was not significantly different between groups. In the UGFN group, quadriceps femoris weakness was found in 19 (79.2%) patients, and in 1 (4.2%) patient at 2-hours and 6-hours postoperation, respectively. No patient in the control group had quadriceps femoris weakness.Conclusion: UGFN decreased intraoperative pain during RFA. However, patients undergoing UGFN should be observed in the hospital for at least 6 hours, and quadriceps muscle power should be tested before hospital discharge.(c) 2022 Asian Surgical Association and Taiwan Robotic Surgery Association. Publishing services by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).