Abstract
Extrinsic warming (to 37°C) does not appear to affect adverse event rates for intravenous injections of iopamidol 300 less than 6 mL/sec but is associated with a significant reduction in extravasation and overall adverse event rates for the more viscous iopamidol 370.
Purpose
To retrospectively determine whether extrinsic warming of the low-osmolality contrast material iopamidol to 37°C prior to intravenous administration at computed tomography (CT) affects extravasation and allergic-like reaction rates.
Materials and Methods
The need to obtain informed patient consent was waived for this HIPAA-compliant and institutional review board–approved analysis. All adverse events related to the intravenous administration of iopamidol during CT examinations occurring 200 days before (period 1) and 200 days after (period 2) the cessation of extrinsic contrast material warming (37°C) for intravenous injections of less than 6 mL/sec at Duke University Medical Center (Durham, NC) were retrospectively reviewed. Adverse event rates were compared by using χ2 statistics.
Results
There were 12 682 injections during period 1 (10 831 injections of iopamidol 300 and 1851 injections of iopamidol 370) and 12 138 injections (10 064 injections of iopamidol 300 and 2074 injections of iopamidol 370) during period 2. Adverse event rates for iopamidol 300 were not affected by extrinsic warming (extravasation rates: 0.30% [32 of 10 831] in period 1 vs 0.23% [23 of 10 064] in period 2, P = .64; allergic-like reaction rates: 0.39% [42 of 10 831] in period 1 vs 0.46% [46 of 10 064] in period 2, P = .74; overall adverse events: 0.68% [74 of 10 831] in period 1 vs 0.69% [69 of 10 064] in period 2, P = .99). Discontinuation of extrinsic warming was associated with significantly increased extravasation and overall adverse event rates for iopamidol 370 (extravasation rates: 0.27% [five of 1851] vs 0.87% [18 of 2074], P = .05; allergic-like reaction rates: 0.16% [three of 1851] vs 0.39% [eight of 2074], P = .42; overall adverse events: 0.43% [eight of 1851] vs 1.25% [26 of 2074], P = .02).
Conclusion
Extrinsic warming (to 37°C) does not appear to affect adverse event rates for intravenous injections of iopamidol 300 of less than 6 mL/sec but is associated with a significant reduction in extravasation and overall adverse event rates for the more viscous iopamidol 370.
© RSNA, 2011
References
- 1 . Manual on contrast media. 7th ed. Reston, Va: American College of Radiology, 2010.
- 2 . Comparative rheology of low- and iso-osmolarity contrast agents at different temperatures. Catheter Cardiovasc Interv 2008;71(1):78–83.
- 3 . Heating contrast media: role in contemporary angiography. Radiology 1987;164(1):276–278.
- 4 . The impact of warmed intravenous contrast material on the bolus geometry of coronary CT angiography applications. Korean J Radiol 2009;10(2):150–155.
- 5 . Non-ionic contrast media: a comparison of iodine delivery rates during manual injection angiography. Br J Radiol 1991;64(761):417–419.
- 6 . Adverse reactions to contrast media in CT: effects of temperature and ionic property. Radiology 1996;199(2):363–366.
- 7 . Frequency of anaphylactoid reactions during intravenous urography with radiographic contrast media at two different temperatures. Radiology 1982;143(2):327–329.
- 8 . Incidence and severity of acute allergic-like reactions to i.v. nonionic iodinated contrast material in children. AJR Am J Roentgenol 2007;188(6):1643–1647.
- 9 . Frequency, management, and outcome of extravasation of nonionic iodinated contrast medium in 69,657 intravenous injections. Radiology 2007;243(1):80–87.
- 10 . Trends in adverse events after IV administration of contrast media. AJR Am J Roentgenol 2001;176(6):1385–1388.
- 11 . Haemodynamic and rheological effects of contrast media: the role of viscosity and osmolality. Eur Radiol 1996;6(Suppl 2):S13–S15.
- 12 . Intravenous contrast medium administration and scan timing at CT: considerations and approaches. Radiology 2010;256(1):32–61.
- 13 . Contrast media reactions and extravasation: relationship to intravenous injection rates. Radiology 1998;209(2):411–416.
- 14 . Nonionic iodinated intravenous contrast material-related reactions: incidence in large urban children’s hospital—retrospective analysis of data in 12,494 patients. Radiology 2009;250(3):674–681.
Article History
Received June 18, 2011; revision requested August 8; revision received August 9; final version accepted September 12.Published online: Feb 2012
Published in print: Feb 2012
