Delirium

Delirium is a serious and potentially life-threatening medical condition characterized by a sudden onset of confusion, altered level of consciousness, and disorganized thinking.

Definition and Diagnosis

Delirium is defined as a disturbance in attention (i.e., reduced ability to direct, focus, sustain, and shift attention) and awareness (reduced orientation to the environment) that develops over a short period of time, usually hours to days. The diagnosis of delirium is based on clinical evaluation and is typically made using standardized criteria such as the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5).

Causes and Risk Factors

Delirium can be caused by a variety of factors, including:

• Infections (e.g., pneumonia, urinary tract infections)
• Medications (e.g., sedatives, anticholinergics, opioids)
• Withdrawal from substances (e.g., alcohol, benzodiazepines)
• Metabolic disorders (e.g., hypoglycemia, hyperglycemia, hyponatremia)
• Neurological conditions (e.g., stroke, seizures, traumatic brain injury)
• Surgery and anesthesia
• Pain and discomfort
• Sleep deprivation and fatigue
• Hospitalization and immobilization

Risk factors for delirium include advanced age, cognitive impairment, history of dementia, and presence of multiple comorbidities.

Symptoms

The symptoms of delirium can vary depending on the underlying cause and individual patient. Common symptoms include:

• Confusion and disorientation
• Altered level of consciousness (e.g., lethargy, agitation)
• Difficulty with attention and focus
• Disorganized thinking and speech
• Mood changes (e.g., anxiety, depression, euphoria)
• Perceptual disturbances (e.g., hallucinations, delusions)
• Sleep-wake cycle disturbances
• Motor symptoms (e.g., tremors, rigidity, myoclonus)

Types of Delirium

There are several subtypes of delirium, including:

• Hypactive delirium: characterized by lethargy and reduced activity
• Hyperactive delirium: characterized by agitation and increased activity
• Mixed delirium: characterized by a combination of hypoactive and hyperactive symptoms

Treatment and Management

The treatment of delirium involves addressing the underlying cause, managing symptoms, and providing supportive care. Strategies for preventing and managing delirium include:

• Identifying and treating underlying medical conditions
• Optimizing medication management
• Promoting sleep and reducing sleep deprivation
• Encouraging mobility and physical activity
• Providing cognitive stimulation and orientation
• Using non-pharmacological interventions (e.g., reorientation, relaxation techniques)
• Considering pharmacological interventions (e.g., antipsychotics, benzodiazepines) for severe symptoms

Prognosis and Complications

Delirium is associated with increased morbidity and mortality, particularly in older adults and those with underlying medical conditions. Complications of delirium can include:

• Prolonged hospitalization and increased healthcare costs
• Functional decline and loss of independence
• Cognitive impairment and dementia
• Increased risk of falls and injuries
• Worsening of underlying medical conditions