Pulmonary edema (American English), or oedema (British English), is fluid accumulation in the air spaces and parenchyma of the lungs. It leads to impaired gas exchange and may cause respiratory failure.
It is due to either failure of the left ventricle of the heart to adequately remove blood from the pulmonary circulation (“cardiogenic pulmonary edema”), see below, or an injury to the lung parenchyma or vasculature of the lung (“noncardiogenic pulmonary edema”), see below.
Whilst the range of causes are manifold the treatment options are limited, and to a large extent, the most effective therapies are used whatever the cause.
Treatment is focused on three aspects, firstly improving respiratory function, secondly, treating the underlying cause, and thirdly avoiding further damage to the lung.
Pulmonary edema, especially in the acute setting, can lead to respiratory failure, cardiac arrest due to hypoxia and death.
Low oxygen saturation and disturbed arterial blood gas readings support the proposed diagnosis by suggesting a pulmonary shunt.
Chest X-ray will show fluid in the alveolar walls, Kerley B lines, increased vascular shadowing in a classical batwing peri-hilum pattern, upper lobe diversion (increased blood flow to the superior parts of the lung), and possibly pleural effusions.
In contrast patchy alveolar infiltrates are more typically associated with noncardiogenic edema.
1.Pulmonary edema with small pleural effusions on both sides.
2.Acute pulmonary edema. Note enlarged heart size, apical vascular redistribution ( circle ), and small bilateral pleural effusions ( arrow ).