Free Practice Questions for CMA Step 2

Explanation: This patient has an acute inferior ST-elevation myocardial infarction (STEMI). When timely percutaneous coronary intervention (PCI) is available at a PCI-capable center, primary PCI within 90 minutes of first medical contact is the preferred reperfusion therapy over fibrinolysis because it achieves higher rates of vessel patency, lower reinfarction rates, and reduced hemorrhagic stroke risk.

Explanation: In patients with heart failure with reduced ejection fraction (HFrEF, LVEF <= 40%) who remain symptomatic despite guideline-directed therapy with an ACE inhibitor/ARNI and beta-blocker, adding a mineralocorticoid receptor antagonist (spironolactone or eplerenone) provides a proven reduction in mortality and hospitalizations. The patient has appropriate serum potassium (< 5.0 mEq/L) and renal function (eGFR > 30 mL/min/1.73 m2) for this therapy.

Explanation: This patient has non-valvular atrial fibrillation with a CHA2DS2-VASc score of at least 4 (Hypertension = 1, Age 65-74 = 1, prior Stroke = 2 points). A prior stroke alone places the patient at high annual risk of recurrent thromboembolism (>= 2 points indicates oral anticoagulation). Direct oral anticoagulants (DOACs) are preferred over warfarin due to a superior safety profile, lower incidence of intracranial hemorrhage, and predictable pharmacokinetics.

Explanation: Severe blood pressure elevation (> 180/120 mmHg) accompanied by acute target organ damage (papilledema, encephalopathy, acute kidney injury) constitutes a hypertensive emergency. Management requires admission to an intensive care unit and intravenous titratable antihypertensive therapy (e.g., labetalol, nicardipine). Mean arterial pressure should be reduced by no more than 20-25% within the first hour to avoid cerebral, coronary, and renal hypoperfusion resulting from autoregulatory shift.

Explanation: Each of the five CURB-65 criteria is present: new confusion, raised urea equivalent to BUN above approximately 20 mg/dL, respiratory rate at least 30/min, systolic pressure below 90 mmHg or diastolic pressure at most 60 mmHg, and age at least 65 years. The score is therefore exactly 5. Severe hypotension and respiratory distress also require urgent resuscitation and assessment for critical care; a mortality score complements clinical judgment.

Explanation: This patient is in acute hypercapnic respiratory failure secondary to an acute exacerbation of COPD (pH 7.31, PaCO2 58 mmHg). Non-invasive positive pressure ventilation (NIV, such as BiPAP) is the first-line evidence-based ventilatory support mode. It unloads fatigued respiratory muscles, improves alveolar ventilation, reduces PaCO2, prevents endotracheal intubation, and reduces mortality. Oxygen therapy in COPD should target an SpO2 of 88-92% to avoid worsening ventilation-perfusion mismatch and hypercapnia.

Explanation: The patient has a high clinical probability of pulmonary embolism (Wells score > 6: tachycardia = 1.5, recent major surgery = 1.5, signs of DVT = 3, PE most likely diagnosis = 3). In patients with high pretest probability who are hemodynamically stable and have no severe renal impairment or severe contrast allergy, computed tomography pulmonary angiography (CTPA) is the diagnostic imaging modality of choice to confirm the clot and guide anticoagulation.

Explanation: According to Light's criteria, a pleural effusion is defined as an exudate if it meets at least one of the following: (1) Pleural fluid protein/serum protein ratio > 0.5 (here 0.66), (2) Pleural fluid LDH/serum LDH ratio > 0.6 (here 0.80), or (3) Pleural fluid LDH > two-thirds of the upper limit of normal serum LDH (280 > 133 U/L). This effusion meets all three criteria, classifying it as an exudate caused by localized inflammation, infection (such as bacterial pneumonia or tuberculosis), or malignant pleural involvement.

Explanation: Active peptic ulcer bleeding with arterial spurting (Forrest Ia) or non-bleeding visible vessel (Forrest IIa) carries an exceptionally high risk of recurrent hemorrhage and mortality if untreated. Current guidelines mandate dual endoscopic hemostatic therapy (mechanical hemoclips or thermal coagulation combined with diluted epinephrine injection) followed by high-dose intravenous proton pump inhibitor therapy (80 mg bolus followed by 8 mg/hour infusion or intermittent high-dose IV PPI for 72 hours) to maintain intragastric pH > 6.0 and stabilize fibrin clot formation.

Explanation: The pain and markedly elevated lipase support acute pancreatitis. Initial care includes analgesia and intravenous crystalloid, commonly lactated Ringer's, adjusted to volume status and repeated clinical assessment. Routine aggressive hydration increases fluid overload without established improvement in outcomes; neither a fixed high infusion rate nor complete fluid restriction is appropriate.