Randomized comparative study between two different techniques of intercostobrachial nerve block together with brachial plexus block during superficialization of arteriovenous fistula.

BACKGROUND: This study compared proximal and distal approaches of intercostobrachial nerve block (ICBNB) combined with infraclavicular brachial plexus block (ICBPB) during superficialization of arteriovenous fistula.

METHODS: Seventy adult patients were randomized to receive ICBPB and 6 ml 0.25% bupivacaine at the level of the 3rd rib in the anterior axillary line between pectoralis minor and serratus anterior muscles (group P) or subcutaneously along the medial side of the upper arm (group D). The primary outcome was the achievement of complete sensory block. Secondary outcomes were onset of analgesia, volume of local anesthetic (LA) supplementation, fentanyl administration, success rate, and conversion to general anesthesia (GA).

RESULTS: Complete sensory block in the medial side of the upper arm was achieved in 91% of patients in group P and 51% in group D. Failure rate of ICBNB was higher in group D (49%) than group P (14%). Conversion to GA was determined by the attending anesthesiologist in 26% of patients in group D and 0% in group P. LA supplementation was required in 5 patients in group P and 11 patients in group D, and the mean volume of LA was statistically higher in group D than group P (9.5 ± 1.5, 7.5 ± 2 ml, respectively). Onset of sensory block was faster in group P than group D (8.75 ± 1.67 and 10 ± 2.14 min, respectively). No differences were observed regarding fentanyl administration.

CONCLUSION: ICBNB proximal approach provides a high success rate with less amount of rescue analgesia compared to the distal approach.