Psychological Disorders: Delirium
American
Description
Reduced ability to maintain attention to external stimuli and to appropriately
shift attention to new external stimuli. Thus at least 1 of:
Questions had to be repeated because attention wandered
Perseverated answers to previous questions
Disorganized
thinking
Confusion
developed over a short period of time
Fluctuating
level of confusion
At least 2 out of 6 of:
Reduced level of consciousness
Perceptual disturbances
Disturbance of sleep-wake cycle
Increased or decreased psychomotor activity
Disorientation to time, place, or person
Memory impairment
Either
of the following:
Evidence that an organic factor initiated and maintained this confusion
Confusion cannot be accounted for by any nonorganic mental disorder
European
Description
Delirium, Not Induced By Alcohol And Other Psychoactive Substances
An etiologically nonspecific syndrome characterized by concurrent
disturbances of consciousness and attention, perception, thinking,
memory, psychomotor behaviour, emotion, and the sleep-wake cycle.
It may occur at any age but is most common after the age of 60 years.
The delirious state is transient and of fluctuating intensity; most
cases recover within 4 weeks or less. However, delirium lasting, with
fluctuations, for up to 6 months is not uncommon, especially when
arising in the course of chronic liver disease, carcinoma, or subacute
bacterial endocarditis. The distinction that is sometimes made between
acute and subacute delirium is of little clinical relevance; the condition
should be seen as a unitary syndrome of variable duration and severity
ranging from mild to very severe. A delirious state may be superimposed
on, or progress into, dementia.
This
category should not be used for states of delirium associated with
the use of psychoactive drugs specified in F10-F19. Delirious states
due to prescribed medication (such as acute confusional states in
elderly patients due to antidepressants) should be coded here. In
such cases, the medication concerned should also be recorded by means
of an additional T code from Chapter XIX of ICD-10.
Diagnostic
Guidelines
For a definite diagnosis, symptoms, mild or severe, should be present
in each one of the following areas:
(a)
impairment of consciousness and attention (on a continuum from clouding
to coma; reduced ability to direct, focus, sustain, and shift attention);
(b)
global disturbance of cognition (perceptual distortions, illusions
and hallucinations - most often visual; impairment of abstract thinking
and comprehension, with or without transient delusions, but typically
with some degree of incoherence; impairment of immediate recall and
of recent memory but with relatively intact remote memory; disorientation
for time as well as, in more severe cases, for place and person);
(c)
psychomotor disturbances (hypo- or hyperactivity and unpredictable
shifts from one to the other; increased reaction time; increased or
decreased flow of speech; enhanced startle reaction);
(d)
disturbance of the sleep-wake cycle (insomnia or, in severe cases,
total sleep loss or reversal of the sleep-wake cycle; daytime drowsiness;
nocturnal worsening of symptoms; disturbing dreams or nightmares,
which may continue as hallucinations after awakening);
(e)
emotional disturbances, e.g. depression, anxiety or fear, irritability,
euphoria, apathy, or wondering perplexity.
The
onset is usually rapid, the course diurnally fluctuating, and the
total duration of the condition less than 6 months. The above clinical
picture is so characteristic that a fairly confident diagnosis of
delirium can be made even if the underlying cause is not clearly established.
In addition to a history of an underlying physical or brain disease,
evidence of cerebral dysfunction (e.g. an abnormal electroencephalogram,
usually but not invariably showing a slowing of the background activity)
may be required if the diagnosis is in doubt.
Includes:
* acute brain syndrome acute confusional state (nonalcoholic)
* acute infective psychosis
* acute organic reaction
* acute psycho-organic syndrome
Differential
Diagnosis
Delirium should be distinguished from other organic syndromes, especially
dementia (F00-F03) from acute and transient psychotic disorders (F23.-),
and from acute states in schizophrenia (F20.-) or mood [affective]
disorders (F30-F39) in which confusional features may be present.
Delirium, induced by alcohol and other psychoactive substances, should
be coded in the appropriate section (F1x.4).
F05.0 Delirium, Not Superimposed On Dementia, So Described
This code should be used for delirium that is not superimposed upon
pre-existing dementia.
F05.1 Delirium, Superimposed On Dementia
This code should be used for conditions meeting the above criteria
but developing in the course of a dementia (F00-F03).
F05.8 Other Delirium
Includes:
* delirium of mixed origin
* subacute confusional state or delirium