A 58-year-old client is scheduled for an intravenous pyelogram to evaluate kidney function and urinary tract abnormalities. Which assessment finding would be most important for the nurse to report to the healthcare provider before the procedure?
1Blood pressure of 140/88 mmHg
2Fasting blood glucose of 110 mg/dL
3Heart rate of 88 beats per minute
4History of shellfish allergy✓ 정답
해설
A history of shellfish allergy is the most critical assessment finding because IVP uses iodine-based contrast dye, and clients with shellfish allergies have a higher risk of allergic reactions to iodine contrast media.
Intravenous pyelography (IVP) is a diagnostic imaging test that uses iodine-based contrast dye to visualize the kidneys, ureters, and bladder. The most important assessment finding to report before this procedure is a history of shellfish allergy, as this indicates a potential for iodine sensitivity.
Shellfish contain high levels of iodine, and patients with shellfish allergies may have cross-reactivity to the iodine-based contrast dye used in IVP procedures. This can cause severe allergic reactions, ranging from mild skin reactions to life-threatening anaphylaxis. Iodine contrast dye is essential for IVP procedures because it allows visualization of the urinary tract structures on X-ray images.
If a patient has a known shellfish allergy, the healthcare team must be notified immediately so that appropriate precautions can be taken. These may include premedication with antihistamines and corticosteroids, use of alternative imaging methods, or having emergency medications ready during the procedure. The risk of contrast-induced allergic reactions is significantly higher in patients with known iodine or shellfish allergies.
Other assessment findings, while important to monitor, do not pose an immediate procedural risk. Mild hypertension, slightly elevated fasting blood glucose, and a normal heart rate are common findings that can be managed but do not contraindicate the IVP procedure or require immediate reporting to the healthcare team before proceeding.
Understanding the Priority: Contrast Media Hypersensitivity
Before an intravenous pyelogram (IVP), the nurse must identify the most critical safety risk. An IVP uses iodinated contrast media (ICM) injected intravenously to visualize the kidneys, ureters, and bladder via X-ray. The primary life-threatening risk associated with this procedure is a hypersensitivity reaction (HSR) to the contrast agent.
Why Shellfish Allergy is the Priority Finding
A documented history of shellfish allergy is the most important finding to report because it signals a heightened risk for an allergic reaction to ICM. While older teaching suggested a direct cross-reactivity due to shared iodine content, current evidence clarifies that the reaction is not to iodine itself. Rather, individuals with one significant atopic allergy, such as a shellfish allergy, have a general predisposition to develop allergic reactions to other substances, including the complex molecules in contrast media. As noted in the literature, HSRs to ICM can range from mild urticaria to severe, life-threatening anaphylaxis [1]. In oncologic and other patient populations, a prior history of allergy is a critical factor in risk stratification before administering ICM [2]. Reporting this history allows the provider to consider premedication protocols or, as explored in cases of documented iodine allergy, the use of alternative non-iodinated agents like gadolinium-based contrast media to safely complete the imaging study [3][4].
Analysis of Other Options
The other assessment findings, while requiring the nurse's attention, do not represent an immediate, life-threatening contraindication to proceeding with the IVP.
- Blood pressure of 140/88 mmHg: This is mildly elevated (Stage 1 hypertension). It is a chronic management concern, not an acute contraindication to a contrast study. The procedure can proceed safely with this reading.
- Fasting blood glucose of 110 mg/dL: This value is slightly above the normal fasting range, indicating impaired fasting glucose. It requires follow-up and patient education but does not pose an immediate procedural risk. The primary renal concern with ICM is contrast-induced nephropathy, for which a mildly elevated glucose is not a direct precipitating factor.
- Heart rate of 88 beats per minute: This is a normal adult heart rate. It is a standard baseline finding and requires no reporting before the procedure.
The nurse's priority is to prevent an immediate allergic emergency. A history of shellfish allergy is the most significant predictor of a potential HSR to ICM, making it the essential finding to communicate to the healthcare provider to ensure patient safety [1][3][4].
References (research sources)
[1]
Hypersensitivity reactions to iodinated contrast media: potential mechanisms and clinical management.Research articleZhong X, Zhao L. (2025) · DOI: 10.3389/fmed.2025.1582072
[2]
Iodinated Contrast Media in Oncologic CT: A Narrative Review of Safety, Risk Stratification, and Practical Considerations.Research articleVasii SO, Crișan FG, Lazăr SM, Ioniță C, Iliescu D, Ioniță I, Malița DC, Voicu M, Voicu A, Udrescu L. (2026) · DOI: 10.3390/diagnostics16101507
[3]
Exploring Gadolinium-Based Contrast Media for Retrograde Pyelography in the Context of Iodine Allergy.Research articleKhan FA, Balbona J, Hernandez DJ. (2023) · DOI: 10.7759/cureus.47439
[4]
Testicular varicocele embolization using CO2, gadolinium and lipiodol as contrast agents in a patient with an iodinated contrast allergy.Research articlePatel V, Thomson B, Ghazal-Aswad B, Makris GC, Diamantopoulos A. (2025) · DOI: 10.1016/j.radcr.2025.06.107
Clinical Priority: Contrast Allergy Screening
Before any procedure involving iodinated contrast media (ICM), the nurse's primary safety assessment must focus on identifying risk factors for hypersensitivity reactions (HSRs). A history of significant atopic allergies, particularly to shellfish, is a well-established risk factor for adverse reactions to ICM. This is not due to iodine cross-reactivity, but rather a general predisposition to allergic responses. Reactions can range from mild urticaria to life-threatening anaphylaxis. Early identification and reporting of this history allow the healthcare provider to implement preventive strategies, such as premedication with corticosteroids and antihistamines or selection of an alternative imaging modality.
Practical Nursing Actions
Detailed Allergy History: Specifically ask about prior reactions to contrast media, shellfish, iodine, and any history of asthma or atopic dermatitis. Document the specific type and severity of any past reaction.
Immediate Reporting: Promptly notify the healthcare provider and radiology team of any positive allergy history before the contrast is prepared or administered.
Premedication Protocol: If the procedure is deemed necessary, anticipate orders for premedication. A common regimen includes oral prednisone and diphenhydramine administered 13, 7, and 1 hour before the procedure.
Emergency Preparedness: Ensure emergency equipment, including oxygen, suction, epinephrine, and intravenous fluids, is readily available. Verify patency of IV access before injection.
Patient Education: Instruct the patient to immediately report any symptoms such as itching, difficulty breathing, throat tightness, or a feeling of warmth during and after the injection.
Monitoring During and After Contrast Injection
Closely monitor vital signs and observe for signs of anaphylaxis for at least 20-30 minutes post-procedure. Most severe reactions occur within the first 20 minutes. Assess airway, breathing, and circulation (ABCs) immediately if symptoms develop. Be aware that a history of shellfish allergy does not guarantee a reaction, but it elevates the patient's risk profile, mandating heightened vigilance.
Intravenous Pyelogram (IVP) — An X-ray examination of the kidneys, ureters, and bladder using iodinated contrast media injected intravenously to assess urinary tract structure and function.
Iodinated Contrast Media (ICM) — Radiopaque substances containing iodine used to enhance visualization of internal structures; can cause hypersensitivity reactions ranging from urticaria to anaphylaxis.
Hypersensitivity Reaction (HSR) — An exaggerated immune response to a substance; in the context of ICM, it is often an anaphylactoid reaction where a history of atopy like shellfish allergy increases risk.
Anaphylaxis — A severe, life-threatening systemic hypersensitivity reaction characterized by airway constriction, hypotension, and shock, which is the primary safety concern with contrast administration.
Atopy — A genetic predisposition to develop allergic diseases such as asthma, allergic rhinitis, or food allergies, which increases the general risk for reactions to contrast media.