What are the types of pulmonary edema?

From the Guidelines

Pulmonary edema can be broadly categorized into cardiogenic and non-cardiogenic types, with cardiogenic pulmonary edema being further subdivided based on the underlying cause, such as left ventricular failure, mitral valve disease, or acute myocardial infarction, as noted in guidelines for the evaluation and management of heart failure 1.

Types of Pulmonary Edema

• Cardiogenic pulmonary edema: This type occurs when the heart is unable to pump blood efficiently, leading to fluid buildup in the lungs due to increased hydrostatic pressure. Common causes include left ventricular failure, mitral valve disease, and acute myocardial infarction.
• Non-cardiogenic pulmonary edema: This type develops from increased vascular permeability rather than pressure changes and encompasses several subtypes, including:
  • Acute respiratory distress syndrome (ARDS): A severe form triggered by conditions like sepsis, trauma, or pneumonia.
  • Neurogenic pulmonary edema: Follows central nervous system injuries.
  • High-altitude pulmonary edema: Affects climbers ascending too quickly.
  • Re-expansion pulmonary edema: Can occur after rapid drainage of a pleural effusion or pneumothorax.
  • Negative pressure pulmonary edema: Results from forceful inspiration against a blocked airway.
  • Drug-induced pulmonary edema: Can be caused by medications like opioids, aspirin overdose, or chemotherapy agents.

Clinical Classification of Pulmonary Hypertension

The 2015 ESC/ERS guidelines for the diagnosis and treatment of pulmonary hypertension provide a comprehensive clinical classification of pulmonary hypertension, which includes 1:

1. Pulmonary arterial hypertension
2. Pulmonary veno-occlusive disease and/or pulmonary capillary haemangiomatosis
3. Pulmonary hypertension due to left heart disease
4. Pulmonary hypertension due to lung diseases and/or hypoxia
5. Chronic thromboembolic pulmonary hypertension and other pulmonary artery obstructions
6. Pulmonary hypertension with unclear and/or multifactorial mechanisms Understanding these different types and classifications is crucial for proper diagnosis and treatment, as management strategies vary significantly depending on the underlying cause of the fluid accumulation in the lungs.

From the Research

Types of Pulmonary Edema

Pulmonary edema can be categorized into two main types:

• Cardiogenic pulmonary edema: caused by elevated hydrostatic pressure in the pulmonary capillaries due to left-sided congestive heart failure 2, 3, 4
• Non-cardiogenic pulmonary edema: caused by changes in permeability of the pulmonary capillary membrane as a result of either a direct or an indirect pathologic process 5, 2, 6

Subcategories of Non-Cardiogenic Pulmonary Edema

Non-cardiogenic pulmonary edema can be further categorized into:

• Low-alveolar pressure edema: caused by upper airway obstruction, such as laryngeal paralysis or strangulation 2
• Elevated permeability edema: caused by conditions such as leptospirosis and acute respiratory distress syndrome (ARDS) 2, 6
• Neurogenic edema: caused by conditions such as epilepsy, brain trauma, and electrocution 2

Characteristics of Cardiogenic and Non-Cardiogenic Pulmonary Edema

• Cardiogenic pulmonary edema is characterized by high capillary pressures, barrier disruption, and increased fluid transfer into the interstitium and alveolar spaces 3, 4
• Non-cardiogenic pulmonary edema is characterized by impaired membrane permeability of the alveolocapillary in the lungs, impaired lymphatic drainage, and no increase in wedge pressure (< 18 mm Hg) 6