During a stress test on a treadmill, which observation by the nurse would necessitate immediate action?

Choice A rationale
A 39-year-old patient experiencing tenderness and swelling in the right calf following a flight may be experiencing deep vein thrombosis (DVT), a condition that can lead to serious complications such as pulmonary embolism if not treated. However, DVT is not immediately life-threatening in most cases.
Choice B rationale
A 58-year-old patient on anticoagulants for atrial fibrillation presenting with black stools is likely experiencing gastrointestinal bleeding, a common side effect of anticoagulant therapy. This can lead to severe blood loss, anemia, and hypovolemic shock, which can be life-threatening if not promptly addressed. Therefore, this patient should be prioritized for assessment.
Choice C rationale
A 67-year-old patient with a gangrenous foot ulcer and a weak pedal pulse likely has peripheral artery disease and an infection that could lead to sepsis if not treated. However, while this condition needs medical attention, it is not as immediately life-threatening as gastrointestinal bleeding.
Choice D rationale
A 50-year-old patient reporting sudden, severe upper back pain could be experiencing a number of conditions, ranging from musculoskeletal strain to aortic dissection. While an aortic dissection is a medical emergency, without additional symptoms such as chest pain, shortness of breath, or loss of consciousness, this patient is not the highest priority.

The correct answer is Choice D.

Choice A rationale: Allergies to shellfish may indicate iodine allergy, relevant for procedures using iodine-based contrast, like PCI. The client’s shellfish allergy must be reported to the PHCP as a precautionary measure to prevent any allergic reaction.

Choice B rationale: Warm sensations during PCI are a common side effect of the contrast dye used in the procedure. This statement does not indicate an immediate concern requiring PHCP notification as it is a standard patient experience.

Choice C rationale: Anxiety in closed spaces, known as claustrophobia, may affect the client's comfort during PCI but can be managed with sedatives. The PHCP should be aware but it’s not as urgent as taking contraindicated medications.

Choice D rationale: Metformin can lead to lactic acidosis, especially when iodine contrast dye is used during PCI. This condition is serious and may result in adverse interactions. The PHCP must be notified immediately.