Perhaps the most common approach to blocking the brachial plexus for hand or arm surgery is the axillary approach. The axillary approach, whether transarterial or with a nerve stimulator, offers a relatively easy to perform block with clear landmarks and a good success rate. However, in some patients access to the axilla is limited by inability of the patient to raise the arm (due to pain or functional limitation) or infection in the axillary region. In these patients, the infraclavicular approach offers an important alternative approach to brachial plexus block.

The second most popular approach after the axillary approach may be the interscalene block. Many practitioners do not have good success with this approach - and it carries the risk of accidental intrathecal or epidural injection, stellate ganglion clock, paralysis of the hemidiaphragm and pnuemothorax. The infraclavicular block does not have these risks - when done properly it carries virtually no risk of pneumothorax (or the other above mentioned problems) while still offering good landmarks to guide the placement of the needle.

Here are the steps to performing this block utilizing the infraclavicular approach:

1. The midpoint of the clavicle is identified and prepped/draped.

2. The patient is placed supine with the head turned away from the arm to be blocked. The arm can be in any position.

3. Use a long needle (6 inches) - this should be a insulated nerve stimulator needle.

4. After local anesthetic for the skin, needle insertion is at this identified midpoint and the needle is directed laterally and posteriorly toward the apex of the axilla. It may be helpful to visualize where the pulse "should" be as a target point.

5. The needle should travel under the pectoralis major muscle en route to the axillary region. The lung lies beneath the medial third of the clavicle and falls away rapidly as you progress laterally. The needle path is in the opposite direction of the receding lung border...thus the risk of pneumothorax is very low.

6. Localize the neurovascular sheath with the nerve stimulator looking for hand twitch. Avoid utilizing a twitch of the biceps muscle - this may be stimulation of the musculocutaneous nerve which can be outside of the sheath.

7. When properly localized, aspirate to make sure that no blood is returned. Inject 40cc of epinephrine containing local anesthetic in divided doses. The epinephrine serves as a "test" each time you inject to help detect intravascular injection.

8. Examples of local anesthetic regimens used are 1.5-2% lidocaine, 1.5% mepivicaine or 0.375-0.5% bupivicaine.