INTRAVENOUS CONTRAST-MEDIA - USE AND ASSOCIATED MORTALITY

Objective: To determine the extent of use and mortality associated with peripheral intravenous injections of radiocontrast media. Design: A retrospective study of injection data was made for the three and a half year period from January 1987 to June 1990 using the Health Insurance Commission database and the records of public hospital x-ray departments. Information about deaths associated with the injections was obtained from a survey of all radiologists and from other relevant sources. Setting and participants: The study related to the entire population of New South Wales and the Australian Capital Territory, approximately 6 million people. Interventions: Intravenous injections of radiographic contrast medium for computed tomographic scans, intravenous pyelograms and venograms. Main outcome: A comprehensive record of intravenous contrast usage and associated mortality in a large community. Results: Between January 1987 and June 1990, 613 581 intravenous injections of radiocontrast media were administered in New South Wales and the Australian Capital Territory. The overall annual incidence of use was estimated to be 2.9% and was markedly age dependent being more than 7% in subjects over 65 years. Eight deaths were documented, representing an overall mortality of 13 per million injections (95% confidence interval [Cl], 5.6-25.7). Mortality appeared to be age related being 35 per million (95% Cl, 12.7-75.6) in those over 65 years compared with 4.5 per million (95% Cl, 0.6-16.4) in those under 65 years. Two of the deaths involved low osmolar contrast media. Conclusions: Death after injection of intravenous contrast medium is a rare event. There was no evidence that mortality was lower with the newer, low osmolar media than with the older, high osmolar media.