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This comprehensive NR 545 Exam study guide contains 300 unique multiple-
choice questions organized into four sections covering cardiovascular disorders,
musculoskeletal and neurological conditions, gastrointestinal and endocrine
disorders, and pharmacology and therapeutics. Each question includes a correct
answer and detailed rationale explaining the pathophysiological mechanisms,
clinical manifestations, diagnostic approaches, and treatment principles. The
content addresses advanced practice nursing concepts including differential
diagnosis, medication management, and evidence-based clinical decision-making.
This resource supports exam preparation by testing clinical knowledge, critical
thinking, and application of advanced practice principles across common primary
care conditions encountered in graduate-level nursing practice.
Section 1: Cardiovascular Disorders (Questions 1-75)
1. A 58-year-old male with a history of hypertension and smoking presents with
acute onset of substernal chest pressure radiating to his left jaw, accompanied by
diaphoresis and nausea. He reports that resting and three sublingual nitroglycerin
tablets have not relieved the pain. What is the most likely diagnosis?
A) Stable angina
B) Unstable angina
C) Myocardial infarction
D) Aortic dissection
Answer: C
Rationale: Myocardial infarction (MI) is characterized by chest pain at rest that is
not relieved by nitroglycerin, often accompanied by diaphoresis, nausea, and a
feeling of impending doom. Pain lasting greater than 30 minutes with ischemia
leads to cardiac tissue death. Unstable angina presents with similar symptoms but
without elevated cardiac biomarkers, while stable angina is relieved by rest or
nitrates.
2. What pathophysiological process most directly causes a myocardial infarction?
,A) Hypotension leading to reduced coronary perfusion
B) Atherosclerotic plaque rupture with thrombosis
C) Coronary artery vasospasm without plaque
D) Myocardial hypertrophy increasing oxygen demand
Answer: B
Rationale: Myocardial infarction is usually caused by rupture of an atherosclerotic
plaque in a coronary artery, leading to thrombus formation and acute occlusion.
This results in an imbalance between myocardial oxygen supply and demand.
Prolonged ischemia for greater than 30 minutes can lead to irreversible cardiac
tissue necrosis.
3. A 65-year-old patient presents with dyspnea on exertion, orthopnea, and
bilateral pedal edema. Physical examination reveals jugular venous distention,
crackles at the lung bases, and an S3 gallop. These findings are most consistent
with:
A) Right-sided heart failure only
B) Left-sided heart failure only
C) Biventricular heart failure
D) Pericarditis
Answer: C
Rationale: Heart failure is a complex clinical syndrome resulting from structural or
functional impairment of ventricular filling or ejection. Left-sided failure causes
pulmonary congestion, reflected by dyspnea, orthopnea, and crackles. Right -sided
failure causes systemic venous congestion, indicated by JVD, peripheral edema,
and hepatomegaly. The presence of both sets of findings indicates biventricular
failure.
4. Which New York Heart Association class describes a patient with marked
limitation of physical activity who is comfortable at rest but develops fatigue,
palpitation, or dyspnea with less than ordinary activity?
A) Class I
B) Class II
C) Class III
D) Class IV
Answer: C
Rationale: NYHA Class III heart failure is characterized by marked limitation of
physical activity. The patient is comfortable at rest, but less than ordinary activity
,causes symptoms such as fatigue, palpitation, dyspnea, or anginal pain. Class I has
no limitation, Class II has slight limitation, and Class IV involves inability to car ry
on any physical activity without discomfort.
5. In a patient with heart failure, which laboratory marker is most sensitive for the
presence of the condition?
A) Serum creatinine
B) B-type natriuretic peptide (BNP)
C) Troponin I
D) C-reactive protein
Answer: B
Rationale: B-type natriuretic peptide (BNP) and N-Terminal pro-BNP are released
from a failing heart in response to increased ventricular wall tension. They are
sensitive markers for the presence of heart failure. Elevated BNP correlates with
the severity of heart failure and is used to differentiate cardiac from pulmonary
causes of dyspnea. Troponin indicates myocardial injury, while creatinine reflects
renal function.
6. What is the recommended initial pharmacologic management for a patient with a
new diagnosis of heart failure with reduced ejection fraction (HFrEF)?
A) Loop diuretics alone
B) ACE inhibitors and beta-blockers
C) Calcium channel blockers
D) Digoxin
Answer: B
Rationale: The cornerstone of pharmacologic management for HFrEF includes
ACE inhibitors (or ARBs) and beta-blockers. These agents reduce morbidity and
mortality by decreasing afterload and myocardial oxygen demand. Loop diuretics
manage fluid overload but do not improve long-term outcomes. Calcium channel
blockers are generally avoided, and digoxin is added for refractory symptoms.
7. A patient is prescribed an ACE inhibitor for heart failure. Which adverse effect
is most important to monitor?
A) Hyperkalemia
B) Hypokalemia
C) Hypernatremia
D) Hypermagnesemia
, Answer: A
Rationale: ACE inhibitors block the conversion of angiotensin I to angiotensin II,
reducing aldosterone secretion. This leads to potassium retention. Patients should
be monitored for hyperkalemia, especially those with renal impairment or those
taking potassium-sparing diuretics. Cough and angioedema are also important
adverse effects.
8. Which statement is true regarding the cardiac conduction system pathway?
A) The AV node is the primary pacemaker
B) The SA node generates impulses at 40-60 beats per minute
C) The electrical signal travels from the SA node to the AV node, then to the
bundle of His, bundle branches, and Purkinje fibers
D) The Purkinje fibers are located in the atria
Answer: C
Rationale: The normal cardiac conduction pathway begins at the SA node (the
primary pacemaker, generating 60-100 beats per minute). The signal travels to the
AV node, then through the bundle of His, down the bundle branches, and through
the Purkinje fibers, causing ventricular contraction. The SA node, not the AV
node, is the primary pacemaker. Purkinje fibers are located in the ventricles, not
the atria.
9. A patient with hypertension and diabetes is found to have a low potassium level
on routine labs. Which medication is the most likely cause of this electrolyte
abnormality?
A) Lisinopril
B) Hydrochlorothiazide
C) Losartan
D) Spironolactone
Answer: B
Rationale: Thiazide diuretics like hydrochlorothiazide inhibit sodium reabsorption
in the distal convoluted tubule, which increases potassium excretion, leading to
hypokalemia. ACE inhibitors and ARBs (lisinopril, losartan) cause potassium
retention (hyperkalemia), and spironolactone is a potassium-sparing diuretic that
also causes hyperkalemia.
10. A 72-year-old male presents with bilateral leg edema, jugular venous
distension, and a systolic murmur that increases with inspiration. What is the most
likely valve disorder?