Negative pressure pulmonary edema (Review)

Negative pressure pulmonary edema (NPPE) is a complication resulting from acute or chronic upper airway obstruction, often posing challenges in recognition and diagnosis for clinicians. If left untreated, NPPE can lead to hypoxemia, heart failure and even shock. Furthermore, the drug treatment of NPPE remains a subject of controversy. The primary pathophysiological mechanism of NPPE involves the need for high inspiratory pressure to counteract upper airway obstruction, subsequently causing a progressive rise in negative pressure within the pleural cavity. Consequently, this results in increased pulmonary microvascular pressure, leading to the infiltration of pulmonary capillary fluid into the alveoli. NPPE exhibits numerous risk factors and causes, with laryngospasm following anesthesia and extubation being the most prevalent. The diagnosis of NPPE often presents challenges due to confusion with conditions such as gastroesophageal reflux or cardiogenic pulmonary edema, given the similarity in initial factors triggering both diseases. Upper airway patency, positive pressure non-invasive ventilation, supplemental oxygen and re-intubation mechanical ventilation are the foundation of the treatment of NPPE. The present review aims to discuss the etiology, clinical presentation, pathophysiology and management of NPPE.