Snapshot A 66-year-old man presents to the emergency department after being found down in a park. He is accompanied by a person who witnessed the fall, who said he had seizure-like activity prior to falling on the floor. The patient is non-participatory on exam but is able to breath on his own. Laboratory studies is significant for a serum sodium of 117 mEq/L. Over the course of 6 hours, his serum sodium was corrected to 135 mEq/L. Subsequently, in the next few days he develops quadrapresis with preservation of eye blinking. Introduction Definition login to view 1 more bullet Epidemiology Risk factors login to view 2 more bullets Pathogenesis Normally, the brain has adaptive mechanisms to prevent swelling in hypotonic states login to view 1 more bullet As the body increases in sodium, it pulls the water out of neurons, dehydrating them, and causing demyelination login to view 1 more bullet Presentation Symptoms/physical exam login to view 7 more bullets Imaging MRI brain login to view 4 more bullets Differential Wernicke encephalopathy login to view 4 more bullets Treatment Preventative login to view 4 more bullets Complications Locked-in syndrome Death