Transient locked-in syndrome after vascular injection during stellate ganglion block.

Intravertebral artery injection of local anesthetics is a rare and alarming complication of neural blocks of the neck. Although seizures, apnea, and loss of consciousness occur, an unusual syndrome with sparing of eye movement might also occur. In transient locked-in syndrome, the patient remains conscious despite inability to breathe or move. The authors report a patient with apparent transient locked-in syndrome that resulted during a stellate ganglion block. This complication is different from frequently reported stroke-like complications. Needle position in the vertebral artery is a possible explanation for the negative aspiration of blood this patient experienced.