It is the first psychiatric disorder that took place in medical practice. As a result, cases of delirium are mostly dealt by physicians. The syndrome, delirium, can be defined as a transient, usually reversible dysfunction in the cerebral nervous system that has an acute or subacute onset and is manifest clinically by wide array of neuropsychiatric abnormalities.
Some patients are considered to be high risk group for developing delirium. They are –
1) Elderly patients
2) Post cardiotomy patients
3) Burn patients
4) Patient with cognitive dysfunction
5) Patients with drug withdrawal
6) Patients with AIDS
7) Patients with a high illness burden
The diagnostic criteria for delirium according to the DSM-IV are –
1. Disturbance of consciousness with reduced ability to focus, sustain or shift attention.
2. Change in cognition that is not better accounted for by preexisting, established or evolving dementia.
3. The disturbance develops over a short period of time and tends to fluctuate during the course of the day.
4. There is evidence from the history, physical examination, or laboratory findings of a general medical condition judged to be etiologically related to the disturbance.
Clinical features of delirium are –
1) Prodrome (restlessness, anxiety, sleep disturbance, irritability) and rapid onset.
2) Rapidly fluctuating course.
3) Attention decreased (easily distractible).
4) Altered arousal and psychomotor abnormality.
5) Disturbance of sleep-wake cycle.
6) Impaired memory.
7) Disorganized thinking and speech.
8) Disorientation (very rarely in case of person).
9) Perceptions altered.
10) Neurological abnormalities like dysgraphia, constructional apraxia, dystonic aphasia, motor abnormalities (tremor, asterixis, myoclonus, reflex and tone changes), and EEG abnormalities.
11) Other features like sadness, irritability, anger or euphoria.
A significant research on the etiology of delirium proposed that derangement in functional metabolism, manifested by cognitive disturbances and slowing of EEG, is the main stem of etiology for delirium. Differential diagnoses for delirium are –
1. Wernicke’s encephalopathy or withdrawal.
2. Hypertensive encephalopathy.
4. Hypoperfusion of CNS.
6. Intracranial bleeding or infection.
7. Meningitis or encephalitis.
8. Poisons or medication.
Delirium can ultimately result in full recovery, progression to stupor and/or coma, development of seizure, progression to chronic brain syndrome, death or any morbidity. But most of the cases of delirium end up in recovery. For the purpose of treatment there are two main steps to take –
1) Treat the underlying cause.
2) Treat the behavioral symptoms.
One of the most widely used groups of pharmacological agents prescribed for the treatment of behavioral symptoms in delirium is antipsychotic. Psychological and environmental supports are also important.