Carbon dioxide as a contrast agent to guide vascular interventional procedures.

OBJECTIVE The purpose of this study was to assess the value and limitations of carbon dioxide (CO2) as a contrast agent to guide vascular interventional procedures. SUBJECTS AND METHODS Twenty-two adults underwent 26 vascular interventional procedures (21 arterial, five venous). We aimed to use only CO2 if possible because these patients had renal insufficiency (n = 21; mean creatinine level, 2.8 mg/dl) or were allergic to contrast material (n = 1). Arterial procedures performed included renal angioplasty or stent (n = 6), iliac angioplasty or stent (n = 5), infrainguinal angioplasty (n = 5), arterial bypass graft angioplasty (n = 3), and thrombolysis (n = 2). Venous procedures included transjugular intrahepatic portosystemic shunt recanalization (n = 3), angioplasty of the venous anastomosis of a thigh dialysis graft (n = 1), and angioplasty of the inferior vena cava (n = 1). RESULTS Twenty-five of the 26 procedures were successfully performed. Of the 26 procedures, eight required no iodinated contrast material and 11 required less than or equal to 20 ml of contrast material. CO2 proved to be inadequate for the remaining seven procedures. Iliac artery angioplasty or stent placement required an average of 9 ml of iodinated contrast material; infrainguinal angioplasty required an average of 22 ml of iodinated contrast material. CONCLUSION CO2 can be successfully used as a contrast agent in a variety of vascular interventional procedures. Such procedures can usually be performed in the iliac and infrainguinal arteries using minimal supplemental iodinated contrast material. However, CO2 failed to provide satisfactory guidance in half of the intraabdominal procedures in our study.