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

Abstract

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 μg vs. 42.71 ± 26.04 μg, 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.