Vasodilator response in the lower extremity induced by contrast medium. I Canine model.

The vasodilator response induced by injections of contrast medium was observed in 11 dogs by electromagnetic flow technique. The experiments were performed to further understand video dilution technique (VDT) measurements in patients with arterial obstructive disease. Responses were observed with regard to the contrast dose relationship, time to peak flow, and abnormal flow produced up to 4 ml caused increasing magnitude of peak flow. The time to peak flow was relatively constant for all doses. Mechanical constrictions depressed th peak flow magnitude but did not affect the time to peak. Emboli produced both depression of the flow magnitude and a delay in time to peak flow. The data suggest that the VDT vasodilatory response curves obtained in patients should correlate with the degree of obstructive disease and delay in the peak flow implies outflow disease.