Proximal paraparesis following spinal anesthesia.

A 70-year-old man with prostatic cancer extending to the urinary bladder underwent transurethral resection of the bladder neck under spinal anesthesia and developed weakness of the proximal lower limbs a few hours after the procedure. The weakness persisted for several months. Because there were no local surgical complications (hematoma, infectious epiduritis, abscess) or bone metastases responsible for nerve root or spinal cord compression, a causal relation between the neurologic deficit and the spinal anesthesia was considered likely. Neurologic deficits are uncommon after spinal anesthesia and can be produced by complications of the surgical procedure (direct nerve injury, hematoma, abscess), arachnoiditis, neurotoxicity of disinfectants or of preservatives added to solutions of anesthetic drugs, or spinal cord ischemia. Precipitating factors for spinal cord ischemia include faulty patient position during the procedure, intraoperative arterial hypotension and injection of vasoconstricting agents.