Addressing Stroke Care: Overcoming Contrast-Allergy Challenges With Rapid Intravenous Dye Preparation

Hypersensitivity reactions to iodinated contrast pose a challenge when urgent neuroimaging is needed in acute stroke. Limited protocols exist for high-risk patients in emergent settings.

To evaluate the safety and efficacy of an emergent intravenous (IV) dye preparation protocol for stroke-alert patients with known contrast allergies, enabling timely neuroimaging.

This retrospective study reviewed stroke-alert patients from 2021 to 2023 at a comprehensive stroke center. Patients with documented IV dye allergies but no history of airway edema or anaphylaxis were included. An emergent IV dye preparation protocol was administered, consisting of diphenhydramine 50 mg IV, famotidine 20 mg IV, and dexamethasone 10 mg IV before contrast CT angiography (CTA) or CT perfusion (CTP). Data analysis included descriptive statistics, and statistical significance was determined using chi-square tests, with a P-value threshold of 0.05.

Of 1,001 stroke-alert patients, 58 (5.8%) had a contrast allergy. Twenty-five of these (43%) received emergent contrast imaging; 16 (64%) were female, with a mean age of 66 ± 15 years. Six of 25 (24%) had a large vessel occlusion or severe carotid stenosis detected by CTA/CTP, compared to two of 26 (7.7%) in the non-contrast group (attributable risk 0.16; 95% confidence interval (CI) -0.07 to 0.39; P = 0.11). No adverse reactions occurred within 24 hours post-imaging. The number needed to treat was six.

The emergent IV dye preparation protocol was safe, enabled timely imaging, and improved detection of treatable large-vessel occlusions in acute stroke patients with contrast allergies.