Nerve Stimulator vs Ultrasound-guided Femoral Nerve Block for Ease of Positioning before Spinal Anesthesia in Fracture Femur Patients: A Randomized Comparative Study

Abstract

Introduction: Severe pain in the fractured femur makes it difficult to position a patient for spinal anesthesia. Femoral nerve block (FNB) has been studied for relief of pain, but studies are inconclusive regarding the superiority of one technique over another, i.e., nerve stimulation vs ultrasound for guidance. Aims and objectives: This study aims to compare the ease of positioning for spinal anesthesia in fracture femur cases using two different techniques of localization of femoral nerve for the block. Materials and methods: In this prospective, randomized, single-blind study, 60 patients of fracture femur were allocated in two equal groups of nerve stimulator (group NS) and ultrasound-guided (group US) femoral nerves block and compared regarding ease of positioning, duration of analgesia, and need for rescue doses of tramadol using SPSS version 26. Results: The patients in the two groups were similar in age, sex, weight, BMI, and initial pain severity (p = 0.920). The visual analog scale (VAS) scores within the groups were markedly reduced at 15 minutes in both the groups (p = 0.000) and between the two groups pain relief was more in group US than group NS at 5 and 10 minutes (p = 0.000 and p = 0.034, respectively), but, was comparable at 15 minutes (p = 0.310). The ease of positioning was observed in 27 patients in group US vs 20 patients NS (p = 0.028) as grade-I (comfortable), whereas grade II (discomfort) present in 3 vs 9 patients (p = 0.053), and grade III (uncomfortable) was seen only in one patient in group NS. The duration of analgesia in group US vs NS was 464.0 ± 170.61 and 282.9 ± 126.85 minutes, respectively (p = 0.003) and lesser need for rescue dose of tramadol (134.20 ± 23.20 vs 174.43.83 ± 47.74 mg) (p = 0.002). The vascular puncture was the main complication observed in group NS. Conclusion: Both the techniques of FNB provided adequate analgesia for fracture femur pain, but the ultrasound technique provided earlyonset, better patient comfort, and longer duration of analgesia than the landmark nerves stimulation technique.

A comparative study between femoral nerve block and intravenous ketamine for pain management during positioning for spinal anesthesia in elderly patients with femur fracture

“…15,16 Second, they used nerve stimulation for the block while ultrasound guided blocks showed more success rates, earlier onset and longer duration of analgesia. 17 Third, they used lateral position during performing SA. There is more chance for overriding of fracture segments in lateral position but it requires minimum flexion, which could have improved patient discomfort.…”