# A nurse is preparing a patient for a cardiac catheterization procedure. Which nursing action should be the highest priority before the procedure? > source: MyMerci (mymerci.kr) > url: https://mymerci.kr/pages/nclex_q.php?qn_id=540236 > language: ko > subject: Adult Health ## 문제 A nurse is preparing a patient for a cardiac catheterization procedure. Which nursing action should be the highest priority before the procedure? A 65-year-old female patient with a history of diabetes is scheduled for cardiac catheterization to evaluate atypical chest pain. ## 보기 1. Confirm that the patient has signed the informed consent form 2. Assess the patient's vital signs including blood pressure and heart rate 3. Confirm the patient has maintained nothing by mouth for eight hours 4. Verify the patient's allergy history, especially to iodine and shellfish **✔ 정답** **정답: 4** ## 해설 Verifying allergy history to iodine/shellfish is the priority because contrast dye contains iodine and can cause severe allergic reactions. Other actions like consent or NPO are important but less critical. ## 심화 해설 Clinical Context and Priority Setting In the sequence of pre-procedural nursing actions for cardiac catheterization, verifying allergy history—specifically to iodine and shellfish—takes precedence as the highest priority. This patient is a 65-year-old female with diabetes, a comorbidity that increases baseline cardiovascular risk. During the procedure, she will be exposed to iodinated contrast media (ICM), which carries a risk of hypersensitivity reactions ranging from mild urticaria to life-threatening anaphylaxis. The foundational principle in nursing prioritization is addressing the factor that poses the most immediate threat to airway, breathing, and circulation. An unrecognized allergy to ICM can precipitate a rapid, severe reaction once contrast is injected, making this assessment the critical safety checkpoint before any other preparatory step. Pathophysiology of ICM Hypersensitivity and Kounis Syndrome Hypersensitivity reactions to ICM can be immune-mediated (IgE-dependent) or non-immune. True IgE-mediated anaphylaxis, though rare, is particularly dangerous because it is often resistant to standard premedication regimens using corticosteroids and antihistamines [1]. When an allergic reaction occurs in the cardiac catheterization lab, it can trigger a unique and severe phenomenon known as Kounis syndrome. This syndrome is defined as the occurrence of an acute coronary event—such as coronary vasospasm or acute myocardial infarction—precipitated by an allergic, hypersensitivity, or anaphylactic reaction [2]. The underlying mechanism involves mast cell activation and the subsequent release of a cascade of inflammatory mediators, including histamine, platelet-activating factor, neutral proteases like tryptase and chymase, and arachidonic acid metabolites [2]. These mediators can cause direct coronary vasoconstriction and erosion or rupture of atherosclerotic plaques. In a patient with diabetes, who likely has some degree of endothelial dysfunction and subclinical coronary artery disease, the vascular substrate is already compromised, potentially modifying and amplifying the presentation of Kounis syndrome [3]. Therefore, an allergic reaction in this context is not merely a dermatologic or respiratory event; it is a direct cardiac threat that can mimic or cause the very chest pain the procedure is intended to evaluate. Clinical Rationale for Prioritizing Allergy Verification Confirming an allergy to iodine or shellfish serves as a critical screen for potential ICM hypersensitivity. While a shellfish allergy does not directly predict an ICM reaction due to different molecular targets, it is a historical marker in nursing assessment protocols that prompts further investigation and communication with the provider. A detailed allergy history allows the team to anticipate reactions, select alternative contrast agents if possible, and have emergency medications like epinephrine immediately available. The retrospective analysis of patients with suspected ICM hypersensitivity highlights the importance of differentiating true immune-mediated reactions from non-immune adverse effects to avoid unnecessary avoidance of ICM while ensuring safe diagnostic imaging . Skin testing, as mentioned in the literature, can identify safe alternative agents for patients with a confirmed history [1]. The other listed nursing actions, while essential, are secondary in the hierarchy of immediate safety. Confirming informed consent (Option 1) is a legal and ethical requirement but does not prevent an immediate physiologic crisis upon contrast injection. Assessing vital signs (Option 2) provides a baseline but does not mitigate the risk of a first-time anaphylactic event. Confirming NPO status (Option 3) is crucial for preventing aspiration during an emergency but is a safety measure for a potential complication, not the primary trigger of an acute, life-threatening cascade that begins the moment contrast is administered. The verification of allergy history is the single action that directly identifies and allows the team to plan for the most rapid and severe patient-specific risk, anchoring it as the highest priority nursing intervention before the procedure begins.References (research sources) - [1]When Premedication Fails: Anaphylaxis to Iodinated Contrast Media in the Cardiac Catheterization Lab Despite Premedication.Research articleTrinh AT, McMurray JC, Pittman LM, Ryaboy IV. (2025) · DOI: 10.1016/j.jaccas.2025.104123 - [2]Contrast Media Side Effects and Kounis Syndrome: Timeo Danaos et Dona Ferentes.Research articleKounis NG, Hung MY, Ceasovschih A, de Gregorio C, Mavromati A, Bernaola M, Koniari I. (2026) · DOI: 10.4274/balkanmedj.galenos.2026.2026-3-89 - [3]Kounis Syndrome Features in Special Populations.Research articleCeasovschih A, Kounis NG, Markos S, Ejubovic M, Cherska M, Barkas F, Ristovski V, Corlateanu A, Sivapalan P, Kotlyarov S, Sorodoc V, Sorodoc L. (2026) · DOI: 10.3390/medsci14020218 ## 임상 시나리오 Pre-Cath Lab Allergy ScreeningThe Critical Safety Checkpoint The highest priority before cardiac catheterization is verifying allergy history, specifically to iodine and shellfish. This directly mitigates the risk of a life-threatening reaction to iodinated contrast media (ICM). An unrecognized allergy can lead to anaphylaxis upon contrast injection. A severe reaction can trigger Kounis syndrome, an acute coronary event caused by the allergic response itself, complicating the procedure. CautionA documented allergy to shellfish does not automatically predict an ICM reaction, but it indicates a higher risk for any allergy. True IgE-mediated reactions to ICM are rare and may not be prevented by standard premedication protocols. ## 핵심 개념 - **Kounis syndrome** — An acute coronary event, such as vasospasm or myocardial infarction, triggered by an allergic or hypersensitivity reaction. - **Iodinated Contrast Media (ICM)** — A radiopaque substance containing iodine used to enhance visibility of vascular structures during procedures like cardiac catheterization. - **Anaphylaxis** — A severe, life-threatening systemic hypersensitivity reaction characterized by rapid onset, airway compromise, and circulatory collapse. - **IgE-mediated reaction** — A true allergic reaction involving immunoglobulin E antibodies, often resistant to standard premedication with corticosteroids and antihistamines. - **Cardiac Catheterization** — An invasive procedure where a catheter is inserted into a heart chamber or vessel to diagnose and treat cardiovascular conditions. ## 같은 주제 문제 - [A nurse is preparing a patient for a cardiac catheterization procedure. 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