Effectiveness of Ultrasonography Guided Femoral Nerve Block for Patient Positioning during Central Neuraxial Block in Elderly Patients for Fracture of Femur - A Prospective, Randomized Control Trial

Abstract

BACKGROUND Central neuraxial blocks, mainly spinal anaesthesia is the preferred anaesthesia over general anaesthesia in fracture of femur surgeries in elderly patients because of various side effects associated with general anaesthesia. However, the majority of the patients during positioning for spinal anaesthesia are associated with severe pain for which positioning becomes difficult. We wanted to assess the effectiveness of ultrasound (USG) guided femoral nerve block (FNB) to reduce pain during the positioning for spinal anaesthesia in fracture femur patients. METHODS It was a randomized control trial conducted on 80 elderly ASA I, II and III patients (45 - 70 years) posted for various femur surgeries under spinal anaesthesia having visual analogue scale (VAS) ≥ 4 during positioning. Patients in group FNB (N = 40) received USG guided femoral nerve block with 0.2 % ropivacaine and in control group (N = 40) didn’t receive any interventions preoperatively. All patients received injection fentanyl during positioning if VAS ≥ 4. Parameters recorded included VAS at baseline, 15 mins and during positioning, anaesthesiologist’s satisfaction (yes or no), total fentanyl consumption and patient’s satisfaction (Likert scale). RESULTS Demographic variables were comparable to each group. VAS in FNB at 15 mins and during positioning was 2.3 ± 1.042 and 3.025 ± 0.831 in comparison to 6.125 ± 0.607 and 7.2 ± 0.822 in control group respectively. Only 5 patients required injection fentanyl and total consumption was 142 ± 3.21 µg in FNB group while all patients in control group required injection fentanyl and total consumption was 1162 ± 4.43 µg. Anaesthesiologists and patients satisfaction were much higher in FNB group. CONCLUSIONS USG - guided FNB is very effective in controlling pain during positioning for spinal anaesthesia in fracture femur patients. KEY WORDS Ultrasound, Femoral Nerve Block, Spinal Anaesthesia, Ropivacaine, Fracture Femur