Digital Block

• Indications include finger fracture, laceration, nail bed injury, and finger/nail bed infection.
• Do not use epinephrine.
• Technique (Fig. 7.1)
  • Pronate the hand (skin on the dorsum is less sensitive).
  • Use two injection sites, at each side of the metacarpophalangeal.
  • Use about 2 mL per nerve (8 mL total).

Wrist Block (Fig. 7.2)

• Median nerve
  • Indications include multiple finger fractures and finger/nail bed lacerations.
  • Technique
    • Supinate the forearm.
    • The needle is placed between the palmaris longus and the flexor carpi radialis, 2 cm proximal to the wrist flexion crease.
    • If paresthesia is elicited, inject 3 to 5 mL at this site.
    • If no paresthesia occurs, then inject 5 mL in fan-shaped fashion.
• Ulnar nerve
  • Indications: ulnar-sided lacerations, reductions of boxer’s fracture (if anesthesia is required)
  • Technique: supinated hand, 6 cm proximal to wrist crease, just radial to flexor carpi ulnaris, 8 to 10 mL (more distal block will miss the dorsal branch, which can be blocked by a wheal ulnar to the flexor carpi ulnaris)
• Radial nerve
  • Indications include thumb and dorsum of hand lacerations.
  • Technique
    • Field block is performed on the pronated hand at the level of the snuff box.
    • This is superficial to the extensor palmaris longus tendon.
    • Start at the snuff box and continue over the entire dorsum of the hand.
    • A dose of 5 to 8 mL is required.

Elbow Block

• Indications include procedures of the hand and wrist.
• Four nerves are involved: median, ulnar, radial, and lateral antebrachial cutaneous.
• Median nerve
  • Draw a line between the medial and lateral condyles of the humerus.
  • The skin wheal is just medial to the brachial artery.
  • Advance the needle until paresthesia is obtained.
  • Inject 3 to 5 mL of lidocaine.
• Ulnar nerve
  • The elbow is flexed.
  • Inject 1 cm proximal to the line that connects the medial epicondyle and the olecranon.
  • Use 3 to 5 mL of lidocaine.
  • Inject very superficially.
  • Too much fluid can cause “compartment syndrome.”
• Radial/musculocutaneous (lateral antebrachial cutaneous nerve)
  • At the intercondylar line, inject 2 cm lateral to the biceps tendon.

Axillary Block

• Indications
  • These include hand and forearm procedures and some elbow procedures.
• Technique (Fig. 7.3)
  • The patient is supine with the shoulder abducted and externally rotated.
  • Palpate the axillary artery in the distal axilla.
  • Some advocate going through the artery, depositing two-thirds of the total anesthetic (20 to 30 mL) behind the artery and one-third superficial to it.
  • Others suggest going on either side of the palpable artery.
  • Think of three nerves around the artery (clock):
    • Median: 12 to 3 o’clock
    • Ulnar: 3 to 6 o’clock
    • Radial: 6 to 9 o’clock
      • Musculocutaneous: separates from the lateral cord of the brachial plexus and pierces the coracobrachialis muscle and travels downward between the biceps brachii and the brachialis muscle
  • Other techniques include ultrasound-guided blocks and nerve stimulation techniques.

Ankle Block

• Indications include any foot and ankle procedure.
• The block must include all five nerves: tibial, deep peroneal, superficial peroneal, saphenous, and sural nerves (Fig. 7.4).
  • Tibial
    • Posterior to the posterior tibial artery, halfway between the medial malleolus and the calcaneus
  • Deep peroneal
    • Just lateral to the anterior tibial artery and the extensor hallucis longus
  • Superficial peroneal and saphenous
    • Field block medially and laterally from a deep peroneal site
  • Sural
    • Lateral border of the Achilles tendon, halfway between the lateral malleolus and the calcaneus

Popliteal Block

• Indications include foot and ankle surgery.
• Technique
  • The patient is prone, with the knee flexed.
  • Identify the popliteal fossa.
  • Inject 7 cm superior to the skin crease, 1 cm lateral to the midline, lateral to the artery.
  • Advance in an anterosuperior direction.
• Add a field block of the saphenous distal to the medial tibial plateau for a more complete block (covers sensation to the medial portion of the foot).
• Ultrasound-guided and nerve stimulation techniques can be used for this block.

Bier Block (Fig. 7.5)

• It is also known as regional IV anesthesia.
• This was developed by August Bier in 1908.
• Indications include hand/wrist procedures and fracture reductions.
• Technique
  • Start the IV infusion in the hand. Place IV catheter. Do not run IV fluid.
  • Place double tourniquets around the upper arm.
  • Exsanguinate the upper extremity.
  • Inflate the more proximal tourniquet.
  • Inject lidocaine without epinephrine (1.5 mg/kg dilute solution or 3 mg/kg, ~50 mL 0.5%) and without any preservative.
  • The tourniquet must stay inflated for 25 to 30 minutes. If the patient has tourniquet pain, the distal tourniquet may be inflated followed by deflation of the proximal tourniquet.
• Risks
  • Tourniquet pain
  • Length of block most often limited by the ability to tolerate the tourniquet
  • Systemic toxicity
  • Theoretic risks: severe cardiovascular and CNS side effects with early release of the tourniquet and a large intravascular bolus of lidocaine