Circulatory Effects of Repeated Intraarterial Injections of Conray 60

In 15 dugs anesthetized with intravenous sodium peniobarbital, the effects of repeated intraarterial injections of methylglucamine iothalamate (Conray 60) on the femoral arterial blood flow were studied. A Statham electromagnetic flowmeter recorded femoral arterial blood flow. All branches of this artery below and behind the inguinal ligament were tied and cut. A catheter was advanced from the left carotid artery so that its tip lay about 2 to 5 cm above the flow probe. In 14 dogs Conray injection through this catheter (1 ml in 2 sec) produced an increase in blood flow from 30 to 1,000% of preinjection level in about 20 sec. In one dog, the injections produced a fall in blood flow. In 12 dogs the blood flow subsequently returned to the resting level in 2 to 5 minutes even after six or seven injections repeated at 10–minute intervals. In three dogs a progressive rise to 208%, 184% and 135% of the blood flow before the first injection had occurred by the end of the study. Thus, there is little evidence that repeated injections of Conray 60, similar to those needed for angiography, produced progressive changes in the vascular bed of the dogʼs hind limb.