A nurse is planning care for a client who has suspected cardiac tamponade. Which of the following diagnostic tests should the nurse anticipate the provider to order first?

A. "A deregulated cytokine storm causes an inflammatory response": Systemic inflammatory response syndrome (SIRS) is characterized by a dysregulated inflammatory response triggered by various insults such as infection, trauma, burns, or ischemia. In SIRS, the immune system responds excessively, leading to the release of pro-inflammatory cytokines (cytokine storm), including tumor necrosis factor-alpha (TNF-α), interleukin-1 (IL-1), and interleukin-6 (IL-6). This cytokine cascade results in widespread inflammation and systemic manifestations, such as fever, tachycardia, tachypnea, and leukocytosis.

B. "The major organ prone to injury during SIRS is the heart": While SIRS can lead to multi-organ dysfunction, including cardiac dysfunction, it does not primarily target the heart. SIRS affects multiple organs, including the lungs, kidneys, liver, and gastrointestinal tract. Cardiac dysfunction in SIRS may result from the inflammatory response, hypoperfusion, or direct myocardial injury.

C. "Spleen dysfunction causes blood clotting issues": SIRS can lead to coagulation abnormalities, but spleen dysfunction is not the primary cause. Coagulation abnormalities in SIRS are often attributed to endothelial dysfunction, activation of the coagulation cascade, and consumption of clotting factors, rather than spleen dysfunction.

D. "Activation of the inflammatory cascade causes increased perfusion": Activation of the inflammatory cascade in SIRS does not typically lead to increased perfusion. Instead, SIRS can lead to alterations in perfusion, including tissue hypoperfusion and microvascular dysfunction. In severe cases, SIRS can progress to septic shock, characterized by profound hypotension and inadequate tissue perfusion.

A. "Vision changes occur when blood vessels leak fluid or blood under a portion of the retina": This statement describes a symptom of diabetic retinopathy, not open-angle glaucoma. In open-angle glaucoma, vision changes primarily result from increased intraocular pressure (IOP) due to impaired drainage of aqueous humor, not leakage of fluid or blood under the retina.

B. "Vision changes occur when the cloudy lens alters the passage of light through the eye": This statement describes a symptom of cataracts, not open-angle glaucoma. Cataracts involve clouding of the lens inside the eye, which affects the passage of light and leads to visual disturbances. Open-angle glaucoma, however, primarily affects the optic nerve and visual field due to increased intraocular pressure.

C. "Vision changes occur when retinal tissue pulls away from the blood vessels in the eye": This statement describes a symptom of retinal detachment, not open-angle glaucoma. Retinal detachment occurs when the retina detaches from the underlying layers of the eye, leading to vision changes and potentially vision loss. Open-angle glaucoma, on the other hand, primarily involves increased intraocular pressure and optic nerve damage.

D. "Vision changes occur when pressure in the eye is increased due to a decrease of aqueous humor": This statement is accurate. In open-angle glaucoma, vision changes occur due to increased intraocular pressure resulting from inadequate drainage of aqueous humor from the eye. This increased pressure can lead to damage of the optic nerve, resulting in peripheral vision loss and potentially blindness if left untreated.