Circulatory effects of iothalamate compounds (Conray) and contrast media of the benzoic acid type

Systemic, Pulmonary and Renal Haemodynamic Effects of Large Intravenous Doses of High and Low Osmolar Contrast Media; An Investigation in the Pig of Ratio 1.5 and Ratio 3 Media

The central, peripheral and renal haemodynamic effects of intravenous infusion (1 ml/s) of large doses (4 ml/kg body weight) of non-ionic (iohexol) and ionic (metrizoate and ioxaglate) contrast media were studied in 24 anaesthetized pigs. All contrast media showed marked haemodynamic effects with an increase of mean right atrial pressure, mean pulmonary arterial pressure, mean pulmonary occlusion pressure, cardiac output and stroke volume. The response of the pulmonary circulation to contrast media was a fall rather than a rise in pulmonary vascular resistance. No significant changes were detected in the renal circulation after infusion of contrast media.

Systemic, Pulmonary and Renal Haemodynamic and Renal Morphologic Effects of Intravenously Infused Iodixanol

The systemic, pulmonary and renal haemodynamic effects following an intravenous infusion (1 ml/s, 4 ml/kg) of a non-ionic iso-osmolar contrast medium (iodixanol) were investigated in 8 pigs. Histopathologic changes occurring after infusion of iodixanol were studied by repeated renal biopsies. Iodixanol caused a significant increase of cardiac output, mean right atrial pressure, mean pulmonary arterial pressure, mean pulmonary arterial occlusion pressure and mean arterial pressure. There was a decrease of the systemic and pulmonary vascular resistances. Most renal biopsies showed no pathologic findings after infusion of iodixanol but in 3 specimens proteinaceous content was observed 15 min after infusion.

Vasodilator response in the lower extremity induced by contrast medium. II. Humans

A new functional test is presented whereby the severity of peripheral obstructive disease can be evaluated during routine angiography utilizing the vasodilator effect of standard contrast medium. The hyperemic response following a sequence of 1 or 2 ml contrast injections into the iliac or femoral arteries is recorded by video dilution technique. The method allows quantitative measure of the functional state of the lower extremity. The vasodilator response in 10 normal human subjects and 23 patients with arterial obstructive disease in compared. Increasing depression of peak flow correlates with increasing symptomatology and a delay in the time to peak flow is seen with small vessel (outflow) disease. The functional severity of outflow disease (trifurcation and superficial femoral artery) as compared with inflow obstruction (iliac arteries) seen at angiography is documented by the test. A new staging of peripheral obstructive disease is proposed based on the results.

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.

Effect of pH, buffer and osmolality of different contrast media on aortic blood pressure in the rabbit

Intra-aortic injections in rabbits of contrast media with a lower osmolality (metrizamide, C29 and ioxaglate) caused significantly less decrease in aortic blood pressure than injections of contrast media with a higher osmolality (diatrizoate, metrizoate and iothalamate) at iodine equivalent concentrations. Increasing the acidity of metrizamide and C29 form pH 7.4 to 5.0 increased the blood pressure fall. Variation of the buffer (phosphate, TRIS and bicarbonate) in metrizamide and C29 solutions at physiologic pH did not cause any difference in response.

Arterial and venous blood pressure and blood flow following femoral angiography with a new non-ionic contrast medium. An experimental investigation in dogs

At femoral angiography in dogs the effects of a new non-ionic contrast medium (C29) were compared with those of one non-ionic medium (metrizamide) and one ionic medium (meglumine/sodium diatrizoate) in current use. In the leg subjected to angiography the pressure gradient over the peripheral vessels decreased and the femoral blood flow increased. The changes induced by the ionic medium were significantly greater than those induced by metrizamide and C29, whereas no significant difference between the two non-ionic media was recorded.

Metrizamide in angiography I. Femoral angiography

In 20 patients the non-ionic Amipaque (metrizamide) and the ionic Isopaque Cerebral (meglumine/calcium-metrizoate) were injected into the femoral, brachial internal iliac or external carotid arteries. Strain gauge plethysmography of the lower leg demonstrated less increase in blood flow following injections of Amipaque (25%) than following injections of Isopaque Cerebral (95%). None of the 20 patients complained of pain following injection af Amipaque; 15 experienced pain following Isopaque Cerebral.