RESUMEN
CO2 has been used increasingly as a contrast agent in both the arterial and venous circulations. CO2 was firstly used as an intravenous contrast medium in the early 1950s for diagnosing pericardial effusion. In the 1970s Cho and Hawkins pioneered the intraarterial use of CO2. CO2 can be used very safely particularly not only in patients with contrast allergies and renal failure, but also in patients undergoing routine angiographic evaluations and many interventional procedures. In venous circulations, CO2 is used for imaging large veins, including the inferior vena cava (IVC), superior vena cava, central veins of the upper extremity, iliac veins, and hepatic and portal veins. Familiarity with the physical properties of carbon dioxide, avoidance of air contamination, catheterization techniques, vascular anatomy, physiologic monitoring, and radiation safety is essential for the safe and effective performance of carbon dioxide angiography. Recently, CO2 has been reported as a "black blood" contrast agent for magnetic resonance angiography. Today, carbon dioxide is used worldwide as a contrast agent for numerous vascular and nonvascular procedures in various organs and arterial circulation below the diagram, as well as in the venous circulation including IVC for various indications, including filter insertion. With the advent of very safe and inexpensive plastic bag delivery system, the safety and ease of gas delivery has been improved.