Epidemiology and management of delirium in critical care

Delirium ("mental confusion'' in French) occurs in one third of adult intensive care unit (ICU) patients. It is a polymorphic cognitive dysfunction but with a mandatory feature: inattention. If this feature is absent, this is not a delirium, and its management is different. Diagnostic tools have been validated in many languages including French, to help managing this disorder that is frequently disconcerting for bedside clinicians as well as for the patient's family. Delirium is a symptom on the same way as pain or fever. When present, it should lead to investigate any organic aetiology. Thus, the cornerstone regarding the preventive and curative treatment of delirium is the detection of all pathological processes disturbing the cerebral functioning: sepsis, lack of oxygen transport to the brain, hydroelectrolytic disorders, toxics (sedatives, analgesics, antibiotics, anticholinergic drugs...). The curative etiological treatment requires the time needed for the improvement of all underlying pathological processes. The symptomatic treatment helps preventing the consequences of potential agitation (falling, self-removal of devices) and reducing associated symptoms if those are distressful for the patient (anxiety, hallucinations, delusion). Non-pharmacological interventions could help improving patient's comfort. Early active mobilisation could reduce the occurrence and duration of delirium if it is integrated in a global approach regarding the minimisation of sedation. Delirium is associated with long-term cognitive dysfunctions giving rise to many ongoing studies to better manage this complex disorder in the ICU setting.