Which of the following interventions should the nurse expect when planning care for this client?

Choice A rationale

Elevated C-reactive protein (CRP) is a marker of general inflammation in the body. While inflammation can contribute to various cardiovascular conditions, including atherosclerosis which can indirectly affect atrial function, an elevated CRP is not a primary or direct cause of atrial fibrillation. CRP levels fluctuate with inflammatory states and are not specifically linked to the electrophysiological disturbances characteristic of A-fib. Normal CRP levels are typically below 10 mg/L.

Choice B rationale

Elevated brain natriuretic peptide (BNP) is primarily indicative of heart failure or increased cardiac workload and ventricular stretch. While atrial fibrillation can occur in the context of heart failure, an elevated BNP level is a consequence of the heart's response to volume overload and pressure changes, rather than a direct cause of the arrhythmia itself. Normal BNP levels vary with age and sex but are generally below 100 pg/mL for younger individuals.

Choice C rationale

Elevated erythrocyte sedimentation rate (ESR) is another non-specific marker of inflammation in the body. Similar to CRP, an elevated ESR can be associated with various inflammatory conditions but is not a direct cause of the electrical abnormalities in the atria that lead to fibrillation. ESR measures the rate at which red blood cells settle in a test tube over an hour, reflecting the presence of inflammation-related proteins in the plasma. Normal ESR values vary by age and sex (e.g., 0-20 mm/hr for men under 50).

Choice D rationale

Elevated thyroid-stimulating hormone (TSH) typically indicates hypothyroidism (underactive thyroid). Thyroid hormones play a crucial role in regulating various bodily functions, including cardiovascular activity and electrophysiology. Both hyperthyroidism (overactive thyroid, characterized by low TSH) and hypothyroidism can predispose individuals to atrial fibrillation by affecting the electrical conduction system of the heart and altering cardiac contractility and rhythm. Normal TSH levels are generally between 0.4 to 4.0 milli-international units per liter (mIU/L).

Rationale for Correct Condition

Endocarditis is characterized by persistent fever, chills, night sweats, fatigue, and embolic manifestations. The presence of mitral valve vegetation on echocardiogram, elevated inflammatory markers, and history of a recent dental infection suggest infective endocarditis rather than pulmonary embolism, tuberculosis, or pneumonia.

Rationale for Correct Actions

Blood cultures confirm bacterial presence and identify the causative organism, guiding antibiotic therapy. Antibiotics are the cornerstone of treatment, targeting the infecting microorganism to prevent systemic complications and cardiac damage.

Rationale for Correct Parameters

Temperature is a key indicator of infection severity and response to antibiotics. Persistent fever may indicate treatment failure or complications. Heart murmur reflects valvular dysfunction from vegetations and must be monitored for progression to heart failure or embolic events.

Rationale for Incorrect Conditions

Pulmonary embolism presents with acute dyspnea and pleuritic chest pain but lacks fever or cardiac involvement. Tuberculosis is associated with chronic cough, night sweats, and lung involvement, which are absent here. Pneumonia causes localized lung infiltrates and productive cough, not cardiac vegetations.

Rationale for Incorrect Actions

Anticoagulant medication is used for thromboembolic conditions but does not treat infective endocarditis. Isolation precautions are needed for airborne pathogens like tuberculosis, not bacterial endocarditis. Bronchodilators are used for airway constriction in COPD or asthma, not cardiac infections.

Rationale for Incorrect Parameters

Sputum specimens are relevant for pulmonary infections but not endocarditis. Pain level is not a direct indicator of endocarditis progression. Partial thromboplastin time monitors coagulation but is unnecessary in the absence of anticoagulation therapy.