Differential Diagnosis for Acute Dyspnea in the Emergency Department

Single Most Likely Diagnosis

• Acute Exacerbation of Chronic Obstructive Pulmonary Disease (COPD): This is a common cause of acute dyspnea, especially in patients with a history of smoking or known COPD. The presentation often includes wheezing, cough, and a history of similar episodes.

Other Likely Diagnoses

• Pneumonia: Can present with acute onset of dyspnea, fever, cough, and chest pain. It's a common and serious condition that requires prompt diagnosis and treatment.
• Asthma Exacerbation: Similar to COPD, asthma exacerbations can cause acute dyspnea, wheezing, and cough. A history of asthma and triggers can help in diagnosing.
• Pulmonary Embolism (PE): Although less common, PE is a critical diagnosis to consider, especially in patients with risk factors such as recent travel, surgery, or family history of clotting disorders. It often presents with sudden onset dyspnea, chest pain, and possibly syncope.
• Heart Failure: Acute decompensated heart failure can cause dyspnea, orthopnea, paroxysmal nocturnal dyspnea, and peripheral edema. A history of heart disease or risk factors for heart failure is relevant.

Do Not Miss Diagnoses

• Cardiac Tamponade: A life-threatening condition where fluid accumulates in the pericardial sac, compressing the heart and impeding its function. It presents with dyspnea, hypotension, and possibly chest pain.
• Tension Pneumothorax: A medical emergency where air enters the pleural space and is not able to escape, causing the lung to collapse. Symptoms include severe dyspnea, chest pain, and hypotension.
• Anaphylaxis: A severe, life-threatening allergic reaction that can cause dyspnea due to airway constriction, along with other symptoms like rash, hypotension, and gastrointestinal distress.

Rare Diagnoses

• High-Altitude Pulmonary Edema (HAPE): Occurs in individuals who ascend to high altitudes too quickly, causing dyspnea, cough, and fatigue.
• Lymphangitic Carcinomatosis: Metastatic cancer to the lungs that can cause dyspnea, cough, and chest pain due to lymphatic obstruction.
• Eosinophilic Pneumonia: A rare condition characterized by an accumulation of eosinophils in the lungs, leading to dyspnea, cough, and fever.

Each of these diagnoses has distinct features and risk factors that can guide the emergency physician in making a timely and accurate diagnosis.