A prospective, double-blinded, randomized comparison of ultrasound-guided femoral nerve block with lateral femoral cutaneous nerve block versus standard anesthetic management for pain control during and after traumatic femur fracture repair in the pediatric population

BACKGROUND Traumatic injury of the femur resulting in femoral fracture may result in significant postoperative pain. As with other causes of acute pain, regional anesthesia may offer a benefit over conventional therapy with intravenous opioids. This study prospectively assesses the effects of femoral nerve blockade with a lateral femoral cutaneous nerve block (FN-LFCN) on intraoperative anesthetic requirements, postoperative pain scores, and opioid requirements. MATERIALS AND METHODS Seventeen pediatric patients (age 2-18 years) undergoing surgical repair of a traumatic femur fracture fulfilled the study criteria and were randomly assigned to general anesthesia with either an FN-LFCN block (n = 10) or intravenous opioids (n = 7). All patients received a general anesthetic with isoflurane for maintenance anesthesia during the surgical repair of the femur fracture. Patients randomized to the FN-LFCN block group received ultrasound-guided nerve blockade using ropivacaine (0.2%/0.5% based on patient weight). At the conclusion of surgery, the airway device was removed once tracheal extubation criteria were achieved, and patients were transported to the post-anesthesia care unit (PACU) for recovery and assessment of pain by a blinded study nurse. RESULTS The final study cohort included 17 patients (n = 10 for FN-LFCN block group; n = 7 for the intravenous opioid group). Although the median of the maximum postoperative pain scores in the regional group was 0, this did not reach statistical significance when compared to the median pain score of 3 in the intravenous opioid group. Likewise, no difference between the two groups was noted when comparing intraoperative anesthetic requirements, opioid requirements (intraoperative, in the post-anesthesia recovery room, and in the inpatient ward), and the time to first opioid requirement postoperatively in the inpatient ward. CONCLUSION This prospective, randomized, double-blinded study failed to demonstrate a clear benefit of regional anesthesia over intravenous opioids intraoperatively and postoperatively during repair of femoral shaft fractures in the pediatric population.