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Difficulty: HardGeneral Internal Medicine

A 67-year-old man presents to the emergency department with a 2-day history of severe, progressively worsening shortness of breath. He reports coughing up frothy, clear sputum and states he had to sleep sitting in a recliner last night due to a feeling of suffocation when lying flat. His medical history includes long-standing hypertension, type 2 diabetes mellitus, and a 45-pack-year smoking history. He takes amlodipine and metformin.

Temperature is 37.0°C (98.6°F), blood pressure is 185/105 mmHg, pulse is 112/min, and respirations are 28/min. Pulse oximetry is 86% on room air. The patient is using accessory muscles of respiration. Jugular venous distension is present up to the angle of the mandible while the patient is sitting at a 45-degree angle. Lung auscultation reveals diffuse, bilateral end-expiratory wheezes and scattered crackles at the lung bases. Cardiac examination shows a regular rhythm, tachycardia, and a distinct S4 gallop. Bilateral 2+ pitting edema is noted in the lower extremities.

Laboratory studies show:
Leukocyte count: 9,200/mm³
Procalcitonin: 0.030.03 ng/mL (normal: <0.15< 0.15 ng/mL)
Arterial blood gas (room air): pH 7.287.28, PaCO 2_2 5555 mmHg, PaO 2_2 5252 mmHg, HCO 3−_3^- 2525 mEq/L

Chest radiograph shows cardiomegaly, peribronchial cuffing, enlarged pulmonary veins, and prominent interlobular septal lines without focal opacities.

Which of the following is the most appropriate next step in the management of this patient?

  1. Intravenous furosemide, sublingual nitroglycerin, and noninvasive positive pressure ventilationAnswer
  2. B
    Inhaled albuterol-ipratropium, systemic methylprednisolone, and oral doxycycline
  3. C
    Intravenous ceftriaxone, oral azithromycin, and inhaled albuterol
  4. D
    Intravenous sodium bicarbonate, inhaled albuterol, and endotracheal intubation
  5. E
    Intravenous piperacillin-tazobactam, aggressive intravenous crystalloid resuscitation, and supplemental oxygen

Answer

The most appropriate management is administering intravenous furosemide, sublingual nitroglycerin, and noninvasive positive pressure ventilation.
The correct sequence of therapies addresses all components of this patient's acute decompensated heart failure (ADHF). The patient's presentation of orthopnea, marked jugular venous distension, an S4 gallop, and radiographic evidence of pulmonary edema confirms ADHF. The wheezing is known as 'cardiac asthma,' occurring when perivascular and peribronchial edema narrows the small airways. The patient is also severely hypertensive and in acute respiratory failure (acute respiratory acidosis on ABG). Management requires a three-pronged approach: 1) Intravenous furosemide to reduce volume overload via diuresis; 2) Sublingual or intravenous nitroglycerin to rapidly reduce preload and afterload, helping the failing left ventricle pump against the severe hypertension (185/105 mmHg); and 3) Noninvasive positive pressure ventilation (NIPPV), such as CPAP or BiPAP, which improves oxygenation, decreases the work of breathing, and further reduces left ventricular preload and afterload by increasing intrathoracic pressure.

Step-by-Step Solution

1
Analyze the clinical presentation to identify the primary etiology of the patient's acute dyspnea.
The combination of orthopnea, severe hypertension, JVD, an S4 gallop, and radiographic evidence of peribronchial cuffing and septal lines strongly indicates acute decompensated heart failure (ADHF) with pulmonary edema.
Differentiating ADHF from a COPD exacerbation or pneumonia is critical because the presence of wheezing ('cardiac asthma') and a heavy smoking history can lead to diagnostic anchoring.
2
Interpret the laboratory and arterial blood gas (ABG) findings.
The normal procalcitonin rules out a bacterial pneumonia trigger. The ABG shows a pH of 7.28, PaCO2 of 55 mmHg, and normal HCO3-, confirming an acute respiratory acidosis due to impaired alveolar gas exchange from pulmonary edema.
Understanding the acid-base disturbance guides respiratory support; acute respiratory acidosis in ADHF is typically managed with noninvasive ventilation rather than bicarbonate or immediate intubation.
3
Determine the optimal multi-modality treatment for ADHF presenting with severe hypertension and respiratory failure.
Select intravenous loop diuretics (furosemide) for volume reduction, rapid-acting vasodilators (nitroglycerin) to reduce severe afterload, and noninvasive positive pressure ventilation (NIPPV) to treat the acute respiratory acidosis and hypoxia.
These interventions work synergistically to decrease left ventricular filling pressures, improve cardiac output, and recruit alveoli, rapidly reversing the pathophysiologic derangements.

Key Concept

Patients with acute decompensated heart failure can present with 'cardiac asthma' (wheezing due to peribronchial edema) and acute respiratory acidosis, requiring immediate management with loop diuretics, vasodilators, and noninvasive positive pressure ventilation.
Estimated Time:2m 0s
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General Internal Medicine

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