Delirium

What is delirium?

Delirium is a sudden decline in brain function leading to mental dysfunction. In a state of delirium, a person experiences rapidly changing mental states. It is also called as an acute confusional state.

What are its main signs and symptoms?

• Rapid changes in mental state are characteristic of delirium. These changes are seen in:

1. Sudden confusion (disorientation)
2. Alertness and attention
3. Feeling and perception
4. Muscular coordination: In a state of delirium, one may move too slowly (hypoactive) or show restless, agitated movements (hyperactive)
5. Sleeping patterns or routine 
6. Emotions and personality
7. Disturbed consciousness
8. Impairment in cognitive skills

• Other symptoms include:

1. Urinary incontinence
2. Reduced short-term memory and recall (Read more: Memory loss causes)
3. Clouding of consciousness or awareness
4. Disorganized thinking that is evident when opinions are voiced
5. Tremor-like movements triggered by changes in the nervous system
6. Difficulty in concentrating

What are its main causes?

Delirium is a multifactorial condition.:  

•  Delirium may occur secondary to an underlying condition, which may include:
  • Dementia (an irreversible, slow onset disorder affecting an individual’s memory)
  • Life-threatening illnesses like stroke; neurologic infections/inflammations like meningitis, encephalitis, and brain abscess; brain tumour; brain injury
  • Major surgery

• Some common, reversible causes include: (non-neurologic causes)
  • Imbalance in chemicals that transmit nerve signals.
  • Drug overdose, adverse drug reactions, or drug interactions.
  • Alcohol abuse. Delirium may also occur as a withdrawal symptom when one tries to stop habitual drinking of alcohol.
  • Electrolyte imbalance, hormonal disorders.
  • Systemic infections, urinary tract infections, respiratory system infections.

 How is it diagnosed and treated?

 Medical history of the person along with patient observation is vital to diagnose delirium.

• Your doctor may also require you to undergo a few tests in order to assess neurological function:
  • Cognitive function tests
  • Test for perception and motor skill evaluation.
  • Your doctor may also evaluate your thinking with some simple and standard questions.
• Other investigations include:
  • Chest X-ray
  • EEG (Electroencephalogram)
  • Cerebrospinal fluid test
  • MRI or CT scans of the brain
  • Urine tests

Delirium shows symptoms similar to dementia. Sudden occurrence of delirium and visual hallucinations help in differentiating it from dementia.

Treatment for delirium addresses the underlying causative factors.

• Non- pharmacological methods include:
  • Supportive care: Medical and hospital care should be given to the patient, attention to social needs and the patient’s environment is essential. Creating a stable and familiar environment helps the patient.
  • Sleeping routines should be maintained. Problems related to sleep should be treated with milk, massage, or herbal tea.
  • Physiotherapy and daily walk helps in improving motor skills.
  • It is always better to hire a professional nurse at home.
  • Behaviour modification therapy.

• Pharmacological therapy includes:
  • Medications to treat underlying precipitating factors like infection, pain, chronic illness, and allergy.
  • Antipsychotic drugs.
  • Rarely, mild sedatives may be used in case of agitation and restlessness.

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4. Prinka, Arvind Sharma. Comparative Study of Delirium in Emergency and Consultation Liaison- A Tertiary Care Hospital Based Study in Northern India. J Clin Diagn Res. 2016 Aug; 10(8): VC01–VC05. PMID: 27656535
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