HEMIBALLISMUS-HEMICHOREA FROM MARKED HYPOTENSION DURING SPINAL-ANESTHESIA

Hemiballism and hemichorea following anesthesia-induced hypotension ha s rarely been described, but a recent case suggests an association Aft er experiencing marked hypotension during spinal anesthesia, a 70-year -old woman developed hemiballism and hemichorea. Involuntary ballistic movements with writhing, consisting of repetitive rotation and flexio n-extension without apparent muscle weakness, affected her left limbs proximally. Low-amplitude, involuntary, choreiform movements involved the distal portions of these limbs. Magnetic resonance imaging demonst rated an area of high signal intensity in the contralateral subthalami c nucleus, suggestive of a focal ischemic lesion. Although such occurr ences are rare, anesthesiologists should be aware of the risk of subth alamic nucleus ischemia following marked hypotension. (C) Acta Anaesth esiologica Scandinavica 42 (1998).