Definition
Delirium is a serious mental abilities disturbance that confused thinking and reduced awareness of your environment as a result. The start of delirium is usually rapid — within hours or a few days.
Delirium can often be traced to one or more contributing factors, such as a severe or chronic medical illness, changes in your metabolic balance (such as low sodium), medication, infection, surgery, or alcohol or drug withdrawal.
Because symptoms of delirium and dementia can be similar, input from a family member or caregiver may be important for a doctor to make an accurate diagnosis.
Causes
Almost any medical illness, intoxication, or medication can cause delirium. Often, delirium is multifactorial in etiology, and the physician treating the delirium should investigate each cause contributing to it. Medications are the most common reversible cause of delirium.
Some of the other common reversible causes include the following:
Hypoxia
Hypoglycemia
Hyperthermia
Anticholinergic delirium
Alcohol or sedative withdrawal
Other causes of delirium include the following:
Infections
Metabolic abnormalities
Structural lesions of the brain
Postoperative states
Miscellaneous causes, such as sensory deprivation, sleep deprivation, fecal impaction, urinary retention, and change of environment
In persons who are elderly, medications at therapeutic doses and levels can cause delirium.
Risk factors
Certain underlying conditions increase the risk of delirium:
●Advanced age
●Underlying brain diseases such as dementia, stroke, or Parkinson disease, particularly when there are current problems with memory
●Use of multiple medications (particularly psychiatric drugs and sedatives), or multiple medical problems
●Sudden withdrawal of a regular medication or cessation of regular alcohol use
●Frailty, malnutrition, immobility
●Advanced cancer
●Undertreated pain
●Immobilization, including physical restraints
●Use of bladder catheters
●Limb fractures
●Interventions, including diagnostic tests
●Poor eyesight or hearing
●Sleep deprivation
●Organ failure, eg, chronic lung disease, heart, kidney, or liver failure