Pulmonary microvascular fracture in a patient with acute respiratory distress syndrome

Objective: To present electron micrographs of lung tissue obtained from a patient exposed to high ventilatory pressures in the context of pulmonary dysfunction and pulmonary hypertension. Design: Case report. Setting: Adult intensive care unit of a university-affiliated teaching hospital. Patients: A patient exposed to high-pressure mechanical ventilation during support for acute respiratory distress syndrome; the acute respiratory distress syndrome in this case was secondary to septic shock. Measurements and Main Results: Scanning electron micrographs of lung tissue, focusing on the internal alveolar surfaces. Findings: Multiple gross disruptions of the alveolar walls, suggestive of stress fractures. Conclusion: High-pressure mechanical ventilation may promote fracturing of the alveolar blood:airspace barrier.