- Published on
Pathology - Acute Respiratory Distress Syndrome
Definition: A critical form of acute lung injury characterized by a PaO2:FiO2 ratio of less than 200 mmHg, accompanied by bilateral alveolar infiltrates on chest X-ray, and occurring in the absence of left ventricular failure.
Epidemiology: Rare occurrence.
Aetiology • Any significant lung injury may result in acute respiratory distress syndrome (ARDS). • Frequent etiologies encompass acute pneumonia, shock, trauma, numerous transfusions, and near-drowning. Pathogenesis • Significant lung injury results in extensive alveolar necrosis, severely disrupting normal gas exchange.
Presentation
• Intense dyspnea accompanied by indications of the underlying etiology. Macroscopy • Both lungs are generally significantly heavy and fluid-filled, frequently exceeding 1000g each (a normal lung weighs 730–400g). Histopathology • The histopathological signature is diffuse alveolar destruction, defined by hyaline membranes lining the alveolar spaces. • Hyaline membranes consist of a mixture of fibrin and necrotic alveolar epithelial cells.
Prognosis: A grave condition with fatality rates ranging from 30% to 50%, contingent upon the underlying etiology. • Survivors typically exhibit persistent pulmonary functional impairments.
Definition: A critical form of acute lung injury characterized by a PaO2:FiO2 ratio of less than 200 mmHg, accompanied by bilateral alveolar infiltrates on chest X-ray, and occurring in the absence of left ventricular failure.
Epidemiology: Rare occurrence.
Aetiology • Any significant lung injury may result in acute respiratory distress syndrome (ARDS). • Frequent etiologies encompass acute pneumonia, shock, trauma, numerous transfusions, and near-drowning. Pathogenesis • Significant lung injury results in extensive alveolar necrosis, severely disrupting normal gas exchange.
Presentation
• Intense dyspnea accompanied by indications of the underlying etiology. Macroscopy • Both lungs are generally significantly heavy and fluid-filled, frequently exceeding 1000g each (a normal lung weighs 730–400g). Histopathology • The histopathological signature is diffuse alveolar destruction, defined by hyaline membranes lining the alveolar spaces. • Hyaline membranes consist of a mixture of fibrin and necrotic alveolar epithelial cells.
Prognosis: A grave condition with fatality rates ranging from 30% to 50%, contingent upon the underlying etiology. • Survivors typically exhibit persistent pulmonary functional impairments.
0 Comments
