CO2 as a Venous Contrast Agent: Safety and Tolerance
CO2 has been used increasingly as a contrast agent in both the arterial and venous
circulations, particularly in patients with hypersensitivity to iodinated contrast material
and renal insufficiency. CO2 can be used as a contrast agent for upper extremity veno-
graphy, wedged hepatic venography, fine-needle transjugular intrahepatic portosystemic
shunt (TIPS), and splenoportography (1-5). With the advent of the plastic bag system
(6), the safety and ease of gas delivery has been improved, allowing multiple injections
from the CO2 bag.