A double-blind, cross-over trial of the non-ionic, low-osmolar contrast medium iohexol (Omnipaque) and the ionic, low-osmolar medium ioxaglate (Hexabrix) at concentrations of 300 mg IIml was carried out in 107 consecutive patients with arterial insufficiency of the lower limbs. The purpose of the study was to observe possible 'carry-over' effects from any of the contrast media, and to evaluate patient discomfort such as pain, adverse reactions, or effect on peripheral blood pressure. No carry-over effect was seen. loxaglate caused less injection pain and heat sensations than iohexol, and showed less effect on the systemic blood pressure.The clinical evidence that low-osmolar contrast media should be used instead of high-osmolar media in angiography is now generally accepted. Comparisons between the various new media are, however, still limited. Increased subjective pain for patients with iohexol injections immediately following ioxaglate injections in peripheral angiography was reported by HAGEN (2). His study was conducted in a cross-over design, and the observation led to the suggestion of a possible 'carry-over' effect between the two media.The present study had the objective to possibly verify this observation, and to evaluate the tolerability of ioxaglate and iohexol in peripheral angiography.
Material and MethodsIohexol (Omnipaque, Nycorned A/S, Oslo, Norway), is a second generation, non-ionic, monomeric contrast medium with an osmolality of 660 mmol/kg H 2 0 at the iodine concentration of 300 mg IImi. Ioxaglate (Hexabrix, Laboratoire Guerbet, Aulnay-sous-Bois, France) is an ionic, dimeric contrast agent with an osmolality of 560 mmol/kg H 2 0 at 300 mg IImi. Since ioxaglate was commercially available in 320 mg IIml only, the pharmaceutical department in our hospital used sterile water for dilution down to the test concentration.One hundred and seven consecutive patients, 67 men and 40 women referred to the radiology department for angiography of the lower extremities because of claudication, were included in the study.The median age was 67 years (range and the weight 67 kg (range 40-105). Three men and one woman were excluded, two due to occluded vessels, and two due to missing data. Diabetic patients were not admitted to the study.The patients fasted 6 hours before angiography. No premedication was given except for atropin intramuscularly or subcutaneously (004 or 0.6 mg depending on the body weight). One patient accidentally received I ml Ketogan. Routine medication, unless recorded, was stopped 24 hours before the examination. All patients received 10 to 20 mllidocain subcutaneously for local anaesthesia in the groin.Informed consent was obtained from each patient entering the study.In our department, the routine procedure for angiography in patients with lower extremity atherosclerosis, involves lumbar aortography, and peripheral run-off examinations with contrast medium injections at the aortic bifurcation and the iliac artery, respectively. For the validity of this study, the injections were done in...