Femoral artery flow and pain during lumbar aortography: comparison of ionic and non-ionic contrast media.

A method is described for non-invasively measuring the increase in lower limb blood flow during transfemoral lumbar aortography. Flow measurements were made using a continuous wave Doppler-shift ultrasound transducer placed over the contralateral femoral artery. The effect of the non-ionic contrast medium B15000 (Iopamidol), conventional contrast medium (Urografin 370) and Urografin 370 plus Lignocaine were compared in a double-blind trial. All three produced an increase in flow which reached a peak between 12 and 45 s after injection. The peak flow following Iopamidol was significantly lower than that from both Urografin 370 alone and with addition of Lignocaine. There was a difference of lesser degree between Urografin 370 plus Lignocaine and Urografin 370 alone; however, this was not statistically significant. The subjective assessments of pain and patient 'discomfort' paralleled these objective flow measurements.