Dr. Jacob Avila teaches the approach to ultrasound guided serratus anterior nerve blocks. This block can be used for pain management in patients with rib fractures. Remember the maximum dose of bupivacaine (a common long acting local anesthetic) is 2.5 mg/kg. A concentration of 0.5% bupivacaine is 5 mg/ml, and 0.25% is 2.5 mg/ml. You will need to use approximately 30 ml to have enough volume to adequately bathe the nerve. A dilution may be needed, as described at the end of the video.