Effect of Different Iodine Concentrations on Patient-Reported Discomfort in Contrast-Enhanced Computed Tomography: A Prospective Comparative Trial

Abstract

Purpose Reducing contrast media injection speed while maintaining iodine flux is a promising workaround to lower or avoid contrast media-related discomfort during CT examinations. This approach demands contrast media with a higher concentration to guarantee excellent image quality. It remains unclear whether these concentration changes affect the patient’s experience. Thus, the aim of this study was to evaluate the influence of different concentrations of intravenous iodinated contrast media on patient discomfort during and after contrast media delivery. Materials and Methods Patients were randomized to receive either Iomeprol 400 mg/ml (group A) or 300 mg/ml (group B) during routinely scheduled CT examinations at our department. The iodine delivery rate and injection time were kept constant in both groups. After examination, study subjects completed a digital questionnaire on different CM-related sensation items using digital visual analogue scales. Results 253 consecutive patients were enrolled in a 6-month period. Most of the patients reported heat sensation in both groups (mean VAS: 5.3 mm in group A vs. 5.0 mm in group B, p = 0.5). Taste sensation also did not differ significantly between both groups (2.4 mm vs. 2.0 mm, p = 0.08). Pain sensation was reported to be significantly lower in group B patients (1.3 mm vs. 1.0 mm, p = 0.005), even though pain sensation in general was reported on a very low level. Other injection-related sensations were rarely reported. Conclusion Patient-reported discomfort during intravenous injection of high-concentration contrast media (400 mg/ml) was low and only marginally different when compared to the injection of contrast media with a lower concentration. The injection of highly concentrated contrast media showed comparable overall patient acceptance, allowing a reduction of the injection speed and volume during examinations. Key Points: Citation Format

Influence of Contrast Media Temperature and Concentration on Patient Comfort and Safety in Computed Tomography

“…In addition, previous research found conflicting results examining the effect of CM viscosity on heat and pain sensation. 20,22 Furthermore, these studies reported that the results that were significant, indicating that low concentrated CM is preferable over high concentrated CM in terms of pain and heat sensation, were small and not of clinical relevance. Hence, it is likely that differences in CM concentration do not have a significant impact on heat or pain sensation.…”

“…However, there is still diversity in the literature concerning these topics. [14][15][16][17][18][19][20][21][22][23][24] The viscosity of CM can be reduced by lowering the CM concentration or by elevating its temperature. 16,17,25,26 Various studies have presented differing perspectives on the impact of CM concentration on patient comfort, safety, and image quality, yielding inconsistent results.…”

“…16,17,25,26 Various studies have presented differing perspectives on the impact of CM concentration on patient comfort, safety, and image quality, yielding inconsistent results. [20][21][22][23][24] In addition, the literature reflects disparities concerning the effect of elevating the CM temperature on patient comfort, safety, and image quality. [14][15][16][17][18][19] Regarding patient safety, Davenport et al 16 demonstrated reduced extravasation rates when prewarming high concentrated CM but found no differences in allergic-like reactions.…”

“…A higher viscosity is believed to result in reduced patient comfort and image quality, as well as an increased risk of adverse events. However, there is still diversity in the literature concerning these topics 14–24 . The viscosity of CM can be reduced by lowering the CM concentration or by elevating its temperature 16,17,25,26 .…”

“…The viscosity of CM can be reduced by lowering the CM concentration or by elevating its temperature 16,17,25,26 . Various studies have presented differing perspectives on the impact of CM concentration on patient comfort, safety, and image quality, yielding inconsistent results 20–24 . In addition, the literature reflects disparities concerning the effect of elevating the CM temperature on patient comfort, safety, and image quality 14–19 .…”