“…For patients under mechanical ventilation admitted in the ICU the percentage of delirium exceeds 75% ( Ely et al, 2004 ). Older age, decreased functional status, cognitive impairment (even mild), depression and comorbidities constitute the most common predisposing factors for delirium, while a subjacent infection, acute or severe illness, pain, anemia, anesthesia and drugs (including sedative hypnotics and anticholinergics) are the most frequently encountered precipitating factors ( Kalimisetty, Askar, Fay, & Khan, 2017 ; Marcantonio, 2017 ; Wakefield, 2002 ). Undernourishment and dehydration on admission might be aggravating factors ( Wakefield, 2002 ).…”