Impact of Ultrasound-Guided Femoral Nerve Blocks in the Pediatric Emergency Department

Abstract

The objective of this study was to compare the duration of analgesia, need for analgesic medications, and pain-related nursing interventions in patients who did and did not receive ultrasound-guided femoral nerve blocks for femur fracture pain. This is a retrospective, preimplementation and postimplementation cohort study. An emergency department log of patients receiving femoral nerve blocks for femur fracture pain was compared with a similar cohort of patients with femur fractures who did not receive nerve blocks. The primary outcome is time from initial pain treatment until the next dose of analgesic. Data were analyzed using Kaplan-Meier methods. Secondary outcomes include number of doses of pain medication, total amount of morphine given, and number of pain-related nursing interventions. Data were analyzed with the Mann-Whitney U test. Eighty-one patients met inclusion/exclusion criteria: 50 in the preimplementation cohort and 31 in the postimplementation group. The median times until next dose of analgesic medication were 2.2 hours (interquartile range [IQR], 1.2-3.4 hours) in the preimplementation group and 6.1 hours (IQR, 3.8-9.5 hours) in the postimplementation group (P < 0.001). The median numbers of doses of pain medication were 0.3 per hour (IQR, 0.25-0.5 per hour) in the preimplementation group and 0.15 per hour (IQR, 0.07-0.3 per hour) in the postimplementation group. The median total doses of morphine were 14.8 µg/kg per hour (IQR, 9.4-19.2 µg/kg per hour) in the preimplementation group and 6.5 µg/kg per hour (IQR, 0-12.2 µg/kg per hour) in the postimplementation group (P = 0.01). The median numbers of nursing interventions were 0.4 per hour (IQR, 0.25-0.5 per hour) in the preimplementation group and 0.15 per hour (IQR, 0.1-0.2 per hour) in the postimplementation group (P < 0.001). Patients who received ultrasound-guided femoral nerve block for femur fracture pain had longer duration of analgesia, required fewer doses of analgesic medications, and needed fewer nursing interventions than those receiving systemic analgesic medication alone.