Delirium

Delirium is an abrupt change in cognitive function from a patient's baseline. Clinical features include a waxing and waning pattern, inattention, and disorganized thinking. A patient's level of consciousness may or may not be affected. Delirium leads to poor outcomes: increased cost, worsened cognition, increased risk of falls, institutionalization, and increased mortality. A single factor can lead to delirium development; however, more often, the cause for delirium is multifactorial. Underlying causes such as an infection, electrolyte imbalance, and deliriogenic medications combined with underlying risk factors contribute to delirium. Delirium is thought to be reversible, although severe, prolonged delirium may have permanent cognitive effects. Following full treatment with clinical improvement, delirium may linger for weeks to months - its trajectory can be challenging to predict. Brain imaging in the neuroscience patient may demonstrate improvement overall; however, delirium may continue to wax and wane.