Nerve Block: Upper Extremity

Background

  • Provides anesthesia in a larger area for wound exploration, irrigation, and repair without distorting local anatomy

Indications

  • Upper extremity fracture
  • Serious trauma/injury or need to perform painful procedure in area covered by distribution of nerve to be blocked

Contraindications

  • Infection overlying injection site
  • Previous allergic reaction to anesthetic
  • Proximal vascular graft or AV fistula

Equipment Needed

  • Chlorhexidine or betadine
  • 5-10 mL Syringe
  • 25-27 gauge needle
  • Local anesthetic (lidocaine without epinephrine, bupivacaine)
  • Sterile gloves
  • Sterile drape

Procedure

  • Obtain informed consent
  • Perform and document a thorough neurovascular examination of the extremity
  • Draw up your anesthetic and load a 25-27 gauge needle
  • Position the patient in position of comfort, placing the arm on a Mayo stand

For Median Nerve block

  1. Locate the palmaris longus (PL) and the flexor carpi radialis (FCR) tendons
  2. you can have the patient flex the middle finger against resistance or pinch their thump and pinky together to help highlight these tendons
  3. some patients do not have PL but you can estimate its general location by going 5 mm medially to the FCR (~midpoint of the wrist)
  4. Prep the skin and drape it in sterile fashion
  5. Insert the needle perpendicular to the skin between the PL and FCR tendons 2-3 cm proximal to the distal crease of the wrist to a depth of 1-2cm
  6. aspirate and then inject 3-5cc of anesthetic then remove needle
  7. allow anesthetic to sit ~10 minutes prior to performing procedure

For Radial Nerve Block

  1. locate the radial styloid and prep and drape area sterily
  2. inject 5cc of anethetic just above the radial styloid aiming medially
  3. extend infiltration laterally using an aditional 5cc of anesthetic

Complications

  • Infection
  • Hematoma
  • Nerve injury
  • Vascular injury

See Also

References