Nerve block: Auricular

Background

• External ear innervated by four sensory nerves
  • Greater auricular nerve
  • Lesser occipital nerve
  • Auricular branch of vagus nerve
  • Auriculotemporal nerve
• Provides anesthesia to the entire ear without distorting anatomy

Indications

• Repair of lacerations
• I+D of hematoma or abscess, or other painful procedures involving the external ear

Contraindications

• Infection at injection site
• Allergy to chosen anesthetic

Equipment

• Syringe, 5-10 mL
• Needle, 25-27 gauge
• Local anesthetic (e.g. lidocaine 1%, bupivacaine 0.25%)
  • Lidocaine with epinephrine may be used for regional block, but epi should not be used for direct infiltration of the ear
• Antiseptic (e.g. Betadine, Chlorhexidine, Alcohol)
• Sterile gloves
• Sterile drape
• Gauze

Technique

Ring block

• Provides anesthesia to entire ear

1. Place patient in supine or sitting position
2. Disinfect skin at the base and superior aspect of ear using chosen antiseptic
3. Insert needle into the skin just inferior to the attachment of the earlobe to the head
4. Advance needle just anterior to the tragus, aspirate while advancing
5. Inject 2-3 mL of anesthetic while slowly withdrawing needle back to the original injection site
6. Redirect and advance needle posterior and superior, aspirating while advancing
7. Inject 2-3 mL anesthetic while withdrawing needle
8. Remove needle and reinsert just superior to the attachment of the helix to the scalp
9. Advance needle just anterior to the tragus, aspirate while advancing
10. Inject 2-3 mL anesthetic while withdrawing needle toward to the original puncture site
11. Redirect and advance needle posterior to the ear
12. Inject 2-3 mL anesthetic while withdrawing needle

Complications

• Infection
• Allergic reaction
• Hematoma
• Inadequate anesthesia
• Cannulation of superficial temporal artery (located medial to the ear, crosses over zygomatic arch)
  • Hold firm pressure with gauze for at least 20-30 minutes