Prophylaxis of Experimental Contrast Medium Injury To the Spinal Cord By Vasodepressor Drugs

Abstract

The protective action of various agents against the severe anatomic injury to the canine spinal cord resulting from the retrograde injection of the contrast material, sodium acetrizoate 70%, was studied. Excellent protection was afforded by a series of vasodepressor agents, including trimethaphan camphor-sulfonate (Arfonad), papaverine HC1, procaine HC1, and Carbocaine (mepivacaine) HC1. The vasopressor agent, levarterenol, exerted no protective action. The protective agents were effective when administered prophylactically, immediately prior to the sodium acetrizoate, but were completely ineffective when administered following the constrast medium. This protective effect is explained by the differential reactivity of the peripheral vascular bed and that of the spinal cord. Because of the stronger reactivity of the peripheral bed, vasodilators act to shunt an intraaortically administered injection mass toward the periphery and away from the cord.