Reducing postischemic paraplegia using conjugated superoxide dismutase

Ann Thorac Surg. 1991 Jun;51(6):911-4; discussion 914-5. doi: 10.1016/0003-4975(91)91004-f.

Abstract

Paraplegia after thoracic aortic aneurysm repair has an incidence of 2.2% to 24%. Oxygen-derived free radicals after reperfusion of an ischemic spinal cord may be partly responsible for neuronal destruction. We studied the effects of polyethylene glycol-conjugated superoxide dismutase (PEG-SOD), a free radical scavenger, as a way of increasing spinal cord tolerance to ischemia. Thirty rabbits underwent 40 minutes of aortic occlusion (a known model of paraplegia). Ten of these animals received 25,000 U/kg of PEG-SOD 24 hours before aortic occlusion and two additional doses of 10,000 U/kg, one before and one subsequent to spinal ischemia. Ten animals received superoxide dismutase in the same dosages as those receiving PEG-SOD. Ten control animals received placebo. All animals were studied for 96 hours, at which time a final neurological examination was performed and the results were recorded. Of the 10 animals treated with PEG-SOD, 2 were completely paralyzed whereas 8 had less (7) or no (1) neurological impairment. Eight of the 10 control animals and 9 of the 10 animals receiving superoxide dismutase were completely paralyzed. None of the control animals or animals receiving superoxide dismutase had a normal neurological examination (p less than or equal to 0.05). Treatment with PEG-SOD before and during occlusion increased the rabbit spinal cord tolerance to a 40-minute ischemic insult. Scavenging free radicals may lessen experimental spinal cord injury.

MeSH terms

  • Animals
  • Aortic Aneurysm / surgery
  • Blood Pressure / drug effects
  • Heart Rate / drug effects
  • Ischemia / complications
  • Ischemia / physiopathology*
  • Male
  • Paraplegia / etiology
  • Paraplegia / prevention & control*
  • Polyethylene Glycols
  • Postoperative Complications
  • Rabbits
  • Spinal Cord / blood supply*
  • Superoxide Dismutase / pharmacology*

Substances

  • Polyethylene Glycols
  • Superoxide Dismutase