Background and Objectives. A prospective, randomized study was performed to investigate the influence of the level of injection on sensory anesthesia when bupivacaine 0.5% adjusted to 37.0 C was used.

Methods. Three milliliters of plain bupivacaine 0.5% were injected at either the L2-3 interspace or the L4-5 interspace. There were 10 patients in each group. The patients were kept sitting for 2 minutes after injection.

Results. No significant difference in maximal level of sensory anesthesia was found ( p = 0.123).

Conclusion. These preliminary results indicate that if a higher level of injection is more suitable for anatomic reasons, it can safely be used without the risk of a much higher level of sensory blockade.