INTRAARTERIAL PROPOFOL IS NOT DIRECTLY TOXIC TO VASCULAR ENDOTHELIUM

To determine if accidental intraarterial injection of propofol results in vascular damage, the effect of bolus administration of propofol on vascular smooth muscle and the endothelium was investigated using the isolated rabbit ear artery. Ear artery segments, removed from urethane anesthetized rabbits, were perfused with Krebs solution (1 ml . min-1) and pressurized to 60 mmHg before being constricted with extraluminal norepinephrine (1.8-4.2 x 10(-6) M). The external diameter of the vessel was measured by an array of light-dependent diodes. Functional responsiveness was determined by the degree of constriction to norepinephrine and the subsequent dilatation of the artery to intraluminal acetylcholine (2 X 10(-6) M) and glyceryl trinitrate (2 X 10(-6) m), and by the myogenic reactivity to a pressure increase from 60 to 100 mmHg. These responses were measured before and after perfusion with 1% propofol for 120 s. Administration of propofol did not result in any vasoactivity nor did it increase the sensitivity to norepinephrine. Vessels maintained their capacity to dilate to both agents, while the myogenic activity was unaffected. Histologic examination of the propofol exposed vessels showed no changes to smooth muscle structure, and the endothelial layer remained intact.