Total spinal anesthesia: a rare complication of intrathoracic intercostal nerve block.

Total spinal anesthesia following intrathoracic intercostal nerve blocks with bupivacaine performed for postoperative pain relief during thoracotomy is described. Possible mechanisms for this complication include: (1) inadvertent placement of the needle through an intervertebral foramen, (2) puncture of a long dural cuff, and (3) intraneural injection with central spread. Recognition of this potential complication is important, and facilities for proper support must be available.