A randomized controlled trial of femoral nerve blockade administered preclinically for pain relief in femoral trauma

BACKGROUND: Analgesia at the location of the accident and on transport for femoral trauma is often delayed or insufficient. In this prospective, randomized, controlled study, we evaluated the prechnical use of femoral nerve blockade for reducing pain and anxiety compared with IV analgesia using metamizol. METHODS: Patients with painful femoral trauma, such as fracture or severe contusion, were randomized to receive at the site of the accident a femoral nerve blockade (n = 31) or IV analgesia with metamizol (n = 31). A visual analog scale (VAS) was used to assess pain and anxiety. Variables were assessed at baseline, during transport and upon arrival at the hospital. RESULTS: In patients receiving the femoral nerve blockade, pain values decreased by half from VAS 86 +/- 6 mm at the site of the accident to VAS 41 +/- 15 mm during transport. Anxiety decreased by half from VAS 84 +/- 11 min to VAS 39 +/- 14 mm. Heart rate decreased by 20 +/- 5 bpm. In the metamizol group, pain, anxiety, and heart rate did not decrease (P < 0.001). Time of treatment was 7.4 +/- 3.5 min longer in the femoral nerve blockade group. CONCLUSION: Preclinically administered femoral nerve blockade effectively decreases pain, anxiety, and heart rate after femoral trauma. Regional blockade is an option for out-of-hospital analgesia administered by a trained physician.