Ascending back pain and headache during attempted epidural placement.

A 30-year-old parturient requested epidural analgesia during labor. Immediately after the epidural space was presumably identified using the loss-of-resistance-to-air technique, she reported severe back pain, followed by neck pain, which progressed to severe unrelenting headache. An emergency computerized tomographic (CT) scan performed during labor showed air in the intracranial subarachnoid space.