[Persistent neurological deficit and adhesive arachnoiditis following spinal anesthesia with bupivacaine containing preservatives].

A 75 year-old female with osteoarthritis of bilateral knee joints was scheduled for right total knee replacement. Her medical history included coronary artery disease, bronchial asthma, and previous surgery of lumbar laminectomy, but she had no neurological deficit before the operation. A 22-gauge spinal needle was inserted at the L 4-5 level and 4 ml of 0.5% bupivacaine with preservatives (Marcain 0.5%) was administered. The sensory block level was noted to L 1 and motor blockade of bilateral feet was achieved within 10 minutes. Anesthesia and operative courses were uneventful for 1.5 hours, and she complained severe low back pain but she could not move her thigh. Eight hours after administration of the anesthetic, her low back pain improved but the anesthetic effects showed no improvement. MRI showed no abnormality of the spinal cord on the following day, but her sensory loss level to L 1 and flaccid paralysis of bilateral lower extremities continued. Myelogram showed inflammation of cauda equina on the fourth day after the operation. She suffered from hydrocephalus two months later and MRI utilizing gadolinium as a contrast medium was consistent with a diagnosis of adhesive arachnoiditis of thoracolumbar region. Her neurological deficit showed no improvement for two years.