Delirium: a key challenge for perioperative care.

Delirium is highly prevalent, occurring in 20% of acute hospital inpatients and up to 62% of surgical patients. It is a significant predictor of poor outcomes including mortality and institutionalisation, however it is often viewed as simply a marker of underlying illness and is frequently overlooked in older adults. Although delirium is commonly comorbid with dementia, it represents a more urgent diagnosis, requiring prompt intervention. Delirium presents most commonly with hypoactive features (e.g. withdrawal and reduced spontaneous movement and speech). The common stereotype of hyperactive delirium tremens (e.g. agitation, hallucinations), although more visible, is less common. All presentations share acute disimprovement of cognitive function. Delirium is a highly predictable and preventable occurrence, however a major barrier to improving delirium care and impacting upon outcomes is that it remains poorly detected, particularly in surgical populations and especially in patients with hypoactive presentations. Routine ward-based screening for delirium, particularly in high-risk populations, and improved staff awareness of the significance of the problem can improve detection rates. Preventative strategies, particularly multicomponent approaches, have been most efficacious in improving patient outcomes. Optimising perioperative risk factors can lead to reduced incidence. Appropriate treatment of delirium requires thorough investigation, management of the underlying illness, avoidance of complications and simplification of the care environment. Studies suggest a role for pharmacological prophylaxis, particularly in relation to anaesthetic and sedative agents used intra- and post-operatively. Furthermore, gathering evidence suggests that judicious use of antipsychotic medications may be helpful in delirium prevention and treatment.