The nurse is caring for a client with a new diagnosis of hyperthyroidism. Which intervention should the nurse prioritize?

Choice A reason: Chest x-ray may show nonspecific findings in pulmonary embolism but is not diagnostic. D-dimer, a fibrin degradation product, is highly sensitive for detecting thrombosis, guiding further imaging like CT pulmonary angiography, making it the priority test in suspected cases.

Choice B reason: Electrocardiogram may show tachycardia or right heart strain in pulmonary embolism but is nonspecific. D-dimer is a sensitive screening test, indicating clot presence, which prompts definitive imaging, making it the preferred initial diagnostic step in suspected pulmonary embolism.

Choice C reason: D-dimer blood test is the most sensitive screening tool for pulmonary embolism, detecting fibrin degradation from clots. Elevated levels prompt CT pulmonary angiography for confirmation, guiding urgent treatment to prevent further embolization, making it the critical test to anticipate.

Choice D reason: Arterial blood gas may reveal hypoxemia in pulmonary embolism but is nonspecific, as other conditions cause similar findings. D-dimer is more diagnostic, identifying clot presence, guiding imaging, and ensuring timely intervention, making it the priority test in suspected cases.

Choice A reason: HIV does not primarily cause a deficiency in antibody production. B-cells produce antibodies, but HIV targets CD4 T-cells, impairing their ability to activate B-cells. This indirectly reduces antibody effectiveness, but the primary mechanism is T-cell destruction, not a direct antibody production deficit, making this incorrect.

Choice B reason: HIV infects and destroys helper T-cells (CD4 cells), critical for coordinating immune responses. By reducing CD4 cell counts, HIV impairs activation of B-cells and cytotoxic T-cells, leading to immune suppression. This is the primary mechanism of AIDS-related immune deficiency, making it the correct explanation for HIV pathology.

Choice C reason: Proliferation of suppressor T-cells (regulatory T-cells) is not a primary HIV mechanism. HIV depletes CD4 cells, not suppressor T-cells, which modulate immune responses. While immune dysregulation occurs, the hallmark is CD4 destruction, not suppressor T-cell proliferation, making this an inaccurate description of HIV’s action.

Choice D reason: HIV does not increase B-lymphocyte numbers. It impairs B-cell function indirectly by destroying CD4 cells, which are needed to activate B-cells for antibody production. B-cell hyperactivity may occur in early HIV, but the primary immune suppression results from CD4 cell loss, not B-cell proliferation.