Delirium in Intensive Care. Incidence and risk factors

Delirium has been documented as a common and serious problem in hospital settings, but its recognition in critically ill patients is made difficult by the inability to interview intubated patients and by the presence of drugs. The objectives of this study were to describe the incidence of delirium in the Intensive care Unit (ICU) and to determine some of the risk factors. It is an analytical, observational and prospective study in an 8-bed general ICU. The participants were 112 consecutive patients aged 18 and older admitted to the ICU for three or more days. Drug consumers and patients with psychiatric disease or cerebral disease were excluded. Daily ratings of the Intensive Care Delirium Screening Checklist (ICDSC) were made by the staff nurses. Other data such as patient's diseases, drug prescriptions and APACHE II were collected. Delirium was present in 11 out of 100 patients-day. APACHE II >= 15, sedative drugs and mechanical ventilation were risk factors for delirium in ICU. The conclusions of this study have determined that delirium is a frequent complication in ICU and that severity of illness, sedative drugs and being intubated are risk factors. Moreover, screening for delirium in the ICU with a validated scale can be made by the staff nurses.