Thoughtful Elder WomanAfter Hospitalization: Confusion? Hallucinations? 

A hospital's environment can be extremely stressful for patients; they are often sick or in pain, or both, feel helpless, and are in unfamiliar surroundings with people they don't know. The combination of this, combined with inadequate sleep and sensory deprivation brought on by a lack of sunlight and movement can lead to a condition known as hospital psychosisICU psychosis, or ICU syndrome.

Read more: Hospital Delirium