Abstract: 【Abstract】Objective To explore the application of the CO2 gas delivery system combined with automatic high-pressure injection system for the imaging of arteriovenous access (AVA) for hemodialysis. Methods A total of 33 uremic patients were subjected to angiography using the Philips Allura Xper FD10 digital subtraction angiographer. A self-built CO2 gas delivery system using a sterile medical plastic bag was connected to the Medrad Mark V ProVis automatic high-pressure injection system. The CO2 volume, injection speed, camera frequency, side effects and other technical parameters were recorded when clear vascular images of
the target parts were obtained. Results A total of 198 angiographic examinations were conducted safely in the 33 patients, in which 31 patients finished the planned intravascular manipulation, and 2 patients had open surgery. To obtain clear images, CO2 5～20 ml/time with the speed of 5～10 ml/sec were used forAVAperipheral vessel imaging and CO2 60～80 ml/time with the speed of 25～30 ml/sec were used for central vein imaging. No untoward reactions were found, except pain of grade 6 by numeric rating scale at the imaging site in one case. Conclusion It is simple and safe to make aCO2 delivery system using a sterile plastic bag in this study. Combined with the automatic high-pressure injection system, CO2 can be injected accurately and automatically, reducing the radiation exposure of medical staff and providing a safe and reliable angiographic method for patients with residual
renal function and allergic to iodine. This system can be widely used clinically.

Key words: Hemodialysis, Arteriovenous access, CO2 angiography, Plastic bag gas delivery system, Automatic high-pressure injection system