[Mental disorders in intensive care medicine - part 1: Principles and diagnostics]

This two-part article on mental disorders in intensive care medicine aims to provide an understanding of the most frequent mental disorders in critical care medicine. Part 1 highlights the basic principles, disturbances and diagnostics and part 2 deals with prevention and therapeutic approaches. The most frequent mental disorders in the intensive care unit are delirium, substance abuse or, respectively, intoxication, suicide attempts, anxiety disorders, depression or psychosis. Mental disorders may be the reason for admission or can develop in the course of intensive care treatment, such as, for example, a post-traumatic stress disorder. The consequences thereof include increased morbidity, mortality, and duration of hospitalization. The early participation of a psychiatrist in the diagnostic process is to be recommended.