How To Do a Median Nerve Block By Richard Pescatore, DO, Delaware Division of Public Health Reviewed / Revised Oct 2021 | Modified Sep 2022 View Patient Education Indications Contraindications Complications Equipment Additional Considerations Relevant Anatomy Positioning Step-by-Step Description of Procedure Aftercare Warnings and Common Errors Tricks and Tips Topic Resources How To Do a Median Nerve Block A median nerve block, done at the wrist, anesthetizes the volar surface of the thenar half of the hand (from the thumb through the radial half of the ring finger) as well as the dorsal surfaces of the corresponding fingertips, excluding the thumb.