Pulmonary edema cardiac arrest due to hypoxia. It is a cardinal feature of congestive heart failure. The term edema is from the Greek (oídēma, "swelling"), from οἰδέω (oidéō, "I swell"). The most common symptom of pulmonary edema is difficulty breathing, but may include other symptoms such as coughing up blood (classically seen as pink, frothy sputum), excessive sweating, anxiety, and pale skin. Shortness of breath can manifest as orthopnea (inability to lie down flat due to breathlessness) and/or paroxysmal nocturnal dyspnea (episodes of severe sudden breathlessness at night). These are common presenting symptoms of chronic pulmonary edema due to left ventricular failure.
Cerebral edema and coma. Interstitial edema occurs in obstructive hydrocephalus due to a rupture of the CSF–brain barrier. This results in trans-ependymal flow of CSF, causing CSF to penetrate the brain and spread to the extracellular spaces and the white matter. Interstitial cerebral edema differs from vasogenic edema as CSF contains almost no protein. Treatment approaches can include osmotherapy using mannitol, diuretics to decrease fluid volume, corticosteroids to suppress the immune system, hypertonic saline, and surgical decompression to allow the brain tissue room to swell without compressive injury. Many studies of the mechanical properties of brain edema were conducted in the 2010s,