LATERAL FEMORAL CUTANEOUS NERVE BLOCK REVISITED - A NERVE STIMULATOR TECHNIQUE

Background and Objectives. Regional block of the lateral femoral cutan eous nerve (LFCN) often has disappointing success rates despite the la rge volumes of local anesthetic used. This study was undertaken to inv estigate the utility of using a nerve stimulator (NS) to localize and block the LFCN. Methods. After obtaining institutional approval and in formed consent, the authors proceeded with a two-stage study. In stage 1, 20 ASA 1 volunteers underwent LFCN block by both a fan and a NS te chnique in a prospective, randomized, crossover study utilizing strict criteria for success and extent of block. To predict clinical utility , 20 patients underwent LFCN block by the NS technique using the same assessment criteria (stage 2). Statistical analysis for the comparison s was completed employing the Fisher's exact or paired t-test as appro priate. P < .05 was considered significant. Results. The NS technique significantly improved the success of LFCN block over the fan techniqu e (100% vs. 40%, P = .00002). The extent of successful blocks was no d ifferent with the two techniques. Success in stage 2 was similar to th at in stage 1 (85%) predicting clinical utility. Conclusions. A NS can be used to localize a purely sensory nerve; such as the LFCN, and imp rove success rates in regional anesthesia.