ABSTRACT
Contrast reactions are unpredictable, unfamiliar and unnerving. Consequently, administration of contrast media can result in release or activation of identical mediators, causing identical end organ responses in an anaphylaxis-like, or anaphylactoid, syndrome. The patient's position and demeanor will indicate the urgency of the situation and separate the differential diagnoses into manageable groups. The uncomfortable, but calm, patient is usually experiencing a cutaneous reaction which may or may not require treatment. The patient who is anxious and agitated, and often sitting up on the table, is most often suffering from respiratory compromise, most commonly laryngeal edema or bronchospasm. These are patients who very much need one's attention. Patients suffering panic attacks may also manifest with symptoms of shortness of breath, palpitations and agitation. Less common reactions seen in this group of patients include pulmonary edema, hypoglycemia, hypertensive reactions and rigors. The subdued or unresponsive patient is generally suffering from cardiovascular decline, due to either vasovagal reaction or diffuse vasodilation and hypotension.
