For Information Only: Additional Blocks for Procedures on the Upper Extremity

These procedures are technically more difficult and require special equipment.
Although discussed for completeness, they are beyond the realm of
a health care provider without expertise in delivering anesthesia.
Bier Block
In a Bier block, also called intravenous regional anesthesia, the affected
hand or forearm is exsanguinated and an upper arm tourniquet is inflated.
The venous circulation of the hand or forearm is then filled with
lidocaine via a catheter placed in a hand vein before exsanguination. In
this manner, the hand and forearm are anesthetized. The block lasts
about 45–60 minutes.
Warning: The tourniquet must work perfectly. If the tourniquet does
not hold its pressure, the injected lidocaine may become systemic and
cause serious side effects (e.g., seizures, cardiac arrhythmias/arrest). In
addition, for a very short procedure (< 15–20 minutes), the lidocaine in
the veins will still be at too high a concentration for the tourniquet to
be deflated. Usually, the tourniquet can be released safely after 25–30
minutes.

Axillary Block
An axillary block essentially anesthetizes the proximal portions of the

nerves that become the median, ulnar, and radial nerves in the forearm
and hand. Technically these portions of the nerves are called the cords
of the brachial plexus. The axillary block is commonly used to provide
anesthesia for hand procedures.
Usually a mixture of lidocaine and bupivacaine is used for infiltration.
An axillary block is useful for procedures that take up to 21⁄2 hours.
The landmark for injection of the anesthetic is the axillary artery, which
is easy to feel in the inner aspect of the upper arm. However, injecting
in the vicinity of the axillary artery is not without risk; possible complications
include injury to the artery or accidental intra-arterial injection.
A nerve stimulator can be used to help to identify the nerve and
thereby lessen these risks. Even so, an axillary block should be done
only by health care providers with expertise in delivering anesthesia.
Bibliography
1. Cousing MJ, Bridenbaugh PO: Neural Blockade in Clinical Anesthesia and
Management of Pain, 3rd ed. Philadelphia, Lippincott Williams & Wilkins, 1997.
2. Longnecker DE, Morgan GE, Tinker JH: Principles and Practices of Anesthesiology,
2nd ed. St. Louis, Mosby, 1997.