Radial

by | Aug 22, 2021

Indications

  • Hand laceration or injury

Contraindications

  • Infection overlying injection site
  • Allergy to local anesthetic

Considerations

  • If performed above the elbow, the radial nerve contains both sensory and motor nerves, and blockade will result in a wrist drop

Equipment

  • 5cc of local anesthetic of choice
  • 25-27G needle
  • Saline Flush
  • Cleansing solution
  • Ultrasound with high-frequency linear transducer
  • Ultrasound transducer sterile cover

Ultrasound

Approach #1 (Elbow)

  1. Position arm extended or held over the abdomen with elbow flexed
  2. Place linear transducer transversely 4-5 cm proximal to the elbow, at the posterolateral aspect
  3. Identify the radial nerve adjacent to the humerus laterally, between the brachioradialis and brachialis muscles
  4. Verify that the nerve does not lie in close proximity to the brachial artery, as this may be the median nerve
  5. Surround target with local anesthetic

Approach #2 (Wrist)

  1. Position with the forearm supinated
  2. Place the transducer in a transverse orientation 3-4 cm proximal to the volar wrist

  1. Locate the radial artery, identify the radial nerve which should be radial to the artery
  2. If the nerve is too close to the artery, trace proximally, where the nerve separates from the artery
  3. Surround target with local anesthetic

Examples

Needle is entering from the posterolateral aspect of the upper arm, and anesthetic can be seen surrounding the radial nerve (*)

 

Source

  1. The POCUS Atlas