Inadvertent Use of Ionic Contrast Material in Myelography

Abstract

A 38-year-old man with chronic low back pain underwent myelography and was inadvertently injected with ionic contrast medium. Within minutes, he started complaining of muscle spasms in his lower extremities, followed by respiratory distress and myoclonus. Immediate intravenous treatment with fluids, antihistamines, and supplemental oxygen was started. Within 1 hour after the myelogram, he was intubated and paralyzed with a neuromuscular blocking agent. Shortly thereafter, he began receiving triple anticonvulsant therapy and a lumbar drain was inserted to allow for the evacuation of cerebrospinal fluid. Electroencephalographic monitoring, which initially showed that the patient was in status epilepticus, subsequently showed no more episodes of seizure activity. Massive rhabdomyolysis, renal failure, and metabolic derangement were prevented. He was then extubated and regained full consciousness. He was discharged on the 13th day of hospitalization with mild amnesia and some cognitive dysfunction. A review of the literature reveals descriptions of 9 of 15 patients who survived similar episodes. We conclude that prompt identification of the contrast medium error and prompt intervention are crucial to increase significantly the chances of survival. Elective paralysis, anticonvulsant therapy, and cerebrospinal fluid drainage are the recommended modes of treatment.

Ascending tonic‐clonic seizure syndrome in a dog following inadvertent intrathecal use of ionic contrast agent

“…Myoclonic movements of the extremities occur and are quickly followed by opisthotonus and grand mal seizures. [1][2][3][4][12][13][14] The patient of this report had similar signs of myoclonus which began 3 hours after ionic contrast injection and progressed rapidly to grand mal seizures. These seizures were resistant to treatment with anticonvulsant medications including diazepam, phenobarbital, and pentobarbital.…”

“…1-4, 11, 12 Treatment recommendations suggested for patients receiving intrathecal ionic contrast material include aggressive seizure control, intubation to maintain a patent airway, raising the head, cerebrospinal drainage or lavage, and aggressive IV fluid support. 1,3,4,11 Because the ionic contrast material is denser than CSF, elevation of the head and neck may slow or prevent the contrast material from reaching the brain. 1,2,11 Drainage of CSF is likely useful to remove as much contrast material from the intrathecal space as possible, as increased contact time results in greater toxicity.…”

“…Approximately 4 hours after contrast media was injected, a cisternal spinal tap was performed based on recommendation from human literature and 1.0 mL (0.16 mL/kg) of grossly normal CSF was removed. 1,3,4 The CSF was not submitted for analysis. The dog's head was elevated and mannitol o (1 g/kg, IV) was administered.…”

“…of ionic contrast material, most commonly during myelography. [1][2][3][4] Nonionic contrast materials rarely cause adverse effects but hyperosmolar ionic contrast agents result in direct neurotoxic damage to the brain and spinal cord parenchyma. Human patients are reported to present with tonic-clonic muscle spasms of the lower extremities that rapidly progress to generalized seizure activity.…”

“…The outcome is frequently fatal, with patients developing hyperthermia, rhabdomyolysis, acute renal failure, disseminated intravascular coagulation, and cardiopulmonary arrest. [1][2][3][4] The purpose of this case report is to describe the successful management of a dog with ATCS after inadvertent intrathecal injection of the ionic contrast material diatrizoate during routine myelography. The dog suffered prolonged respiratory arrest, refractory seizure activity, pneumonia, and delayed return to neurologic function but ultimately survived with no permanent effects.…”