Patients with a history of hypersensitivity reaction to iodinated contrast medium and given iodinated contrast during an interventional pain procedure

Abstract

In patients with a history of a hypersensitivity reaction to iodinated contrast medium, iodinated contrast medium is avoided, antihistamine and steroid premedication are given, or a gadolinium-based contrast agent is employed. Six patients with a history of a hypersensitivity reaction to iodinated contrast medium and who were not premedicated had an unintentional injection of iodinated contrast. None of the patients developed a moderate or severe reaction. All patients had gadopentetate dimeglumine in one of their injections; three had repeated injections of the gadopentetate. The lack of a significant reaction may be due to any or all of the following: questionable history of iodinated contrast reaction, low dose of iodinated contrast given, concomitant injection of (epidural) steroid, and slower absorption from epidural compared with intravenous injection. While it is reassuring to know that there is a low possibility of a moderate to severe reaction in these patients, every effort should be made to avoid this scenario, appropriate drugs and resuscitation equipment should be immediately available, and the patients should be observed adequately and followed for the possibility of late reactions. Recent publications have called for caution in the use of gadolinium-based contrast agents.

Limited duration of hypersensitivity reactions to contrast and exact documentation of such adverse events

“…With great interest, I read the paper by Benzon and colleagues 1. They report on six patients with a history of a previous contrast medium (CM)-induced hypersensitivity reaction (HR).…”

Iodinated contrast media hypersensitivity: recommendations for the pain practitioner

“…Benzon et al recently described outcomes of inadvertent iodinated contrast media (ICM) administration in a case series of six patients undergoing interventional pain procedures following unintentional allergy alert overrides 1. Despite the absence of premedication, there were no breakthrough reactions in any of these patients, calling into question the clinical relevance of contrast allergy labels in this setting.…”

“…Low rates of such responses can be estimated from recent reports describing adverse events following epidural administration5 and combined epidural, intra-articular and intramuscular (medial branch block) administration 6. Thus, management of an ICM allergy label in this setting derives largely from vascular administration data, and has centered largely on two principles1: pre-emptive administration of a premedication protocol, and2 the substitution of ICM with non-iodinated contrast agents. Neither of these strategies are ideal and associated with their own shortcomings.…”

Gadolinium use for interventional pain procedures: where we are and where we are heading

“…The article by Benzon et al 9 in this issue of Regional Anesthesia & Pain Medicine describes six cases of patients with documented HR to iodinated contrast medium (ICM) who were inadvertently administered iodine-based contrast dyes without premedication. None experienced any serious reactions, which raises questions regarding the accuracy of documented hypersensitivity, the clinical and legal implications and how best to manage these patients.…”

“…One might argue based on the six cases presented by Benzon et al 9 that an unsubstantiated history of a HR is irrelevant in pain procedures given the low volume of ICM injected, the low probability of a true allergy, and the lack of negative consequences demonstrated in the article. However, this would be a simplistic interpretation of a complex issue.…”