The document discusses acute mental status changes that can occur in intensive care unit patients. It describes conditions like delirium, decreased levels of consciousness, and their causes. Delirium is the most common disorder and results from factors like infection, medications, electrolyte imbalances, and pre-existing dementia. The document recommends screening patients for delirium regularly using tools like the Confusion Assessment Method, and treating underlying causes and symptoms with antipsychotics like haloperidol. Delirium is associated with increased mortality, length of stay, and long-term cognitive impairment.