Arteriovenous fistula angiography using carbon dioxide as contrast medium

The aim of this study is to obtain an alternative angiographic diagnostic method which can be used in patients at a high risk for the use of iodine contrast medium. Twenty-six patients with chronic renal failure whose fistulas were assessed by digital angiography were first evaluated using iodine contrast medium. Subsequently, carbon dioxide was used as contrast medium, and the images were printed in angiographic film. The angiographic studies were evaluated by opacification, radiological diagnosis and vessel diameter by two independent vascular surgeons; the author performed a comparative analysis of the measurement of the artery and the vein, and respiratory frequency before and after contrast injection. The results obtained with the statistical analysis using kappa coefficient showed agreement between the two doctors and were 0.3217 for opacification, 0.5583 for radiological diagnosis and of 0.4298 for the analysis of vessel diameter. For the carbon dioxide technique, no significant difference was seen in the comparative analysis of the measures of the artery (p=0.3657) and vein (p=0.2041), in the position measurements and dispersion; the analysis of the position measurements and dispersion for respiratory frequency showed no significant difference. We concluded that this method can be used as an alternative for angiographic study in patients with history of allergy or risk of nephrotoxicity. (author)