Blocking the Pain: Ultrasound Guided Nerve Blocks in the ED

Ultrasound-guided nerve blocks are no longer just a niche skill for fellowship-trained ultrasound specialists—they are a core component of modern multimodal pain management in the ED. Endorsed by ACEP, nerve blocks can offer rapid, targeted pain relief without relying solely on systemic opioids, making everything from rest to imaging and procedural workups significantly more comfortable for patients. Today, Dr. Carlos Mikell, UC Davis Emergency Ultrasound Faculty and nerve block expert, joins us to share why every emergency physician should adopt nerve blocks as part of their practice. We’ll break down the top ED blocks, explore innovative indications like genicular nerve blocks for knee pain, and discuss essential safety protocols and how to get started – or become more comfortable – with blocks in your ED. **Why Nerve Blocks Belongs in the ED** - **Targeted Relief:** Delivers effective, localized pain management as part of a multi-modal pain control approach, sparing patients some of the systemic side effects of opioids. - **Facilitates ED Workup:** Relieves movement-related pain, making imaging, patient transport, and local procedures far easier and more comfortable for the patient. - **ACEP Endorsement:** ACEP’s policy statement formalizes ultrasound-guided nerve blocks as an essential skill for all emergency physicians—not just ultrasound fellowship graduates. - **Analgesia, Not Complete Anesthesia:** The goal in the ED is *regional analgesia* (taking pain down to a manageable, functional level safely) rather than dense, surgical anesthesia. **The Most Common ED Nerve Blocks** According to data from the National Ultrasound Guided Nerve Block Registry: 1. **Fascia Iliaca Plane / Femoral Nerve Block (~36%):** - *Indications:* Hip fractures, mid-shaft/distal femur fractures, hip dislocations, and severe thigh trauma. - *Safety Profile:* Highly safe; target plane is centimeters away from the main neurovascular bundle in a easily compressible site. <!--THE END--> 2. **Erector Spinae Plane (ESP) Block:** <!--THE END--> 1. - *Indications:* Back pain, renal colic, shingles, and rib fractures. <!--THE END--> 3. **Forearm Blocks (Median, Ulnar, Radial):** <!--THE END--> 1. - *Indications:* Distal forearm fractures, complex lacerations, and hand procedures. <!--THE END--> 4. **Serratus Anterior Plane (SAP) Block (~7%):** <!--THE END--> 1. - *Indications:* Rib fractures, pre/post-chest tube insertion pain, and chest wall abscesses. - *Tip:* Hydro-dissect with normal saline first to identify the fascial plane before injecting local anesthetic, and consider adding dexamethasone to extend duration. **Innovative Block Spotlight: Genicular Nerve Block** - **Target:** Three of the primary sensory branches of the sciatic/femoral nerves supplying the anterior knee. - **Indications:** Acute knee trauma/fractures, acute-on-chronic knee pain, and severe osteoarthritic flare-ups. - **Safety & Execution:** Low-volume block (~10 mL total). *Pearl:* Omit the inferior-lateral genicular injection to avoid unintentional peroneal nerve block and foot drop. **Streamlining Nerve Blocks in Your Department** To move nerve blocks from a rare procedure to a routine clinical tool: - **ED Infrastructure:** Build standardized EMR order sets, procedure note templates, and dedicated nerve block supply carts/kits. - **Departmental Support:** Designate a point person to coordinate credentialing, interdisciplinary pathways (e.g., trauma, orthopedics), and physician/nurse/tech education. - **Hands-on Training:** Utilize cadaver labs, simulation, and scanning shifts to build faculty and resident confidence. **Non-Negotiable Safety Guidelines & LAST Prevention** Nerve blocks are generally low-risk, but vigilance is critical to avoid complications like **Local Anesthetic Systemic Toxicity (LAST)** or direct nerve injury: 1. **Patient Selection:** Avoid in uncommunicative patients (who cannot report paresthesias or tinnitus), areas at high risk for compartment syndrome, or pre-existing severe nerve deficits. 2. **Monitoring:** Keep patients on cardiac telemetry for 30–60 minutes post-block for central or high-volume blocks (>10 mL or above the elbow/knee). 3. **Dosing Buffer:** Calculate maximum weight-based local anesthetic doses every time; stay within 60–70% of the maximum dose to maintain a safety buffer. 4. **Intralipid Availability:** Ensure **20% Intralipid** is immediately accessible in the ED pharmacy or brought directly to the bedside. 5. **Injection Technique:** Never point the needle directly at a nerve. Inject into the fascial plane, stop immediately if you encounter resistance, and perform frequent aspirations every 3–5 mL. What is your favorite ultrasound-guided nerve block? What barriers do you encounter to doing blocks in the ED? We’d love to hear form you! Connect with us on social media @empulsepodcast or connect with us on ucdavisem.com **Hosts:** Dr. Julia Magaña, Professor of Pediatric Emergency Medicine at UC Davis Dr. Sarah Medeiros, Professor of Pediatric Emergency Medicine at UC Davis **Guest:** Dr. Carlos Mikell, Assistant Professor of Emergency Medicine and Ultrasound Faculty at UC Davis **Resources:** ACEP Policy Satement: Ultrasound Guidelines: Emergency, Point-of-care, and Clinical Ultrasound Guidelines in Medicine, June 2016 ACEP Now: How To Build an Ultrasound-Guided Nerve Block Program By Arun Nagdev, MD; Kaitlen Howell, MD; Akash Desai, MD; David Martin, MD; and Daniel Mantuani, MD, MPH | on January 6, 2023  ACEP Sonoguide: Nerve Blocks NURVE Block Registry Brown J, Milgrim F, Driver L, et al. Efficacy and Safety of Adjunct Medications in ED Ultrasound-Guided Nerve Blocks: A National Ultrasound-Guided NeRVE (NURVE) Block Registry Study. Acad Emerg Med. 2025 Dec;32(12):1299-1308. doi: 10.1111/acem.70128. Epub 2025 Aug 27. PMID: 40873157. Goldsmith A, Driver L, Duggan NM, et al. Complication Rates After Ultrasonography-Guided Nerve Blocks Performed in the Emergency Department. JAMA Netw Open. 2024 Nov 4;7(11):e2444742. doi: 10.1001/jamanetworkopen.2024.44742. Erratum in: JAMA Netw Open. 2024 Dec 2;7(12):e2455847. doi: 10.1001/jamanetworkopen.2024.55847. PMID: 39535792; PMCID: PMC11561692. \*\** Thank you to the UC Davis Department of Emergency Medicine for supporting this podcast and to Orlando Magaña at OM Productions for audio production services. *Disclaimer: The opinions expressed on this podcast are those of the hosts or guests and do not necessarily reflect the views of UC Davis Department of Emergency Medicine, UC Davis Health, or their parent organizations.*