Single-injection brachial plexus anesthesia for arteriovenous fistula surgery of the forearm: a comparison of infraclavicular coracoid and axillary approach.

BACKGROUND AND OBJECTIVES: The surgical site for the creation of an arteriovenous fistula at the lateral aspect of the distal forearm may be faster and more effectively blocked with the infraclavicular coracoid approach than with the axillary approach for brachial plexus block.

METHODS: Sixty uremic patients scheduled for the creation of an arteriovenous fistula at the forearm were randomized to receive a single-injection brachial plexus block with 35 to 50 mL mepivacaine 0.95% with epinephrine using the infraclavicular coracoid approach (IC group) or the perivascular axillary approach (AX group). A distal muscular contraction elicited by a nerve stimulator at current <0.5 mA was used in all patients.

RESULTS: At 30 and 45 minutes, complete loss of sensation was observed more often in group IC than AX in the cutaneous distribution of musculocutaneous nerve (62% v 30% [P < .05] and 69% v 40%, respectively [P < .05]), but at 60 minutes the difference was not statistically significant. In other areas, analgesia and motor block were achieved at a similar rate. In 3 patients surgery could not be performed under the block due to changes in schedule or the use of a brachial tourniquet. Patient satisfaction was equally high in both groups.

CONCLUSIONS: Blockade of the musculocutaneous nerve developed faster with the infraclavicular coracoid approach than with the axillary approach. The infraclavicular coracoid approach may be preferable in patients scheduled for the creation of an arteriovenous fistula at the forearm.