Delirium |X Flashcards
What is the definition of delirium?
a “state of mental confusion that develops quickly and usually fluctuates in intensity”
What are the 4 key criteria for diagnosis of delirium based on DSM-IV?
A. Disturbance of attention or arousal/consciousness
B. Worsening confusion
C. Acute onset with fluctuating course, with disturbance of the sleep wake cycle
D. Evidence from the history, examination or investigations that the delirium is a direct consequence of:
i. a general medical condition
ii. substance intoxication
iii. substance withdrawal
iv. multiple aetiologies (often)
What is the definition of arousal?
The magnitude of response to perceived stimuli
What is the definition of cognition?
The mental process of thinking and knowing, including aspects such as awareness, perception, memory, language, reasoning, and deciding
What is the definition of consciousness?
Alertness plus awareness
What is the definition of attention?
The ability to focus the mind, and sustain focus, on an environmental stimulus, idea, or series of connected ideas
What is the definition of awareness?
Self perception or inward sensibility
What is the definition of alertness?
Ability to respond to external stimuli
Criteria A of DSM-IV diagnosis of delirium, how do patients with disturbance of consciousness typically present (2)?
How do you test for it?
- The key is reduced attention, which is the ability to focus, sustain, or shift mental focus.
- Patients demonstrate distractibility, drowsiness, or reduced vigilance.
Mostly you observe it during interview, but can test it with tasks that require concentration e.g. spelling backwards, serial 7’s, digit span.
Criteria B of DSM-IV diagnosis of delirium, how do patients with worsening confusion typically present (2)?
- A change in cognition
e. g. memory deficit, reasoning or language disturbance or mental slowing
OR
- The development of a perceptual disturbance
e. g. hallucinations that is not better accounted for by a pre-existing, established, or evolving dementia
Criteria C of DSM-IV diagnosis of delirium, how do patients with acute onset with fluctuating course typically present (2)?
- The disturbance develops over a short period of time (hours to days)
- It tends to fluctuate during the course of the day, in particular being worse at night.
What are 4 associated features that might present with delirium in addition to the core diagnostic features?
- delusions (often paranoid)
- Delusions tend to be fleeting, and lack any system or logic. - emotional changes (anxiety, fear, depression)
- motor changes (slowness, restlessness, agitation)
- hallucinations (often formed and animated)
Why is hypoacative or apathetic delirium hard to spot?
The patient is quiet, withdrawn, lacks initiative and responds poorly to interaction.
Often mistaken for depression
In delirium, behaviours such as aggression or restlessness are a response to what (4)?
- Pain
- Constipation
- Frustration at inability to communicate needs
- Being frightened by delusions, hallucinations or misperceptions
How common is delirium?
Common
How serious is delirium?
Emergency - It is essential that delirium is treated with seriousness, as it often reflects severe underlying illness and has a high mortality.
What is the prevalence of delirium in hospitals?
20%
How much more likely are patients with dementia to develop delirium?
5-10%
What are 5 negative consequences of delirium?
- Increased mortality (1 year mortality following an admission with delirium is 40%)
- Prolonged hospital admission
- Higher complication rates
- Institutionalization
- 3x increased risk of developing dementia
What are 5 predisposing risk factors and 6 precipitating risk factors of delirium?
Predisposing:
- Dementia
- Sensory impairment e.g. vision
- Older age (>65 years)
- Multiple co-morbidities
- Physical frailty
Precipitating
- Metabolic abnormalities
- Systemic infection
- Surgery
- Drug initiation/withdrawal
- Acute brain disease
- Hypoxia
What are 7 prevention strategies that should be applied to patients at high risk?
- Keep orientated, promote the familiar
- Facilitate vision and hearing (glasses, light, hearing aid)
- Keep hydrated and well fed
- Reduce medication, avoid anticholinergic drugs and opiates
- Keep mobile and active
- Promote night time sleep
- Minimise provocation (noise, tubes, restraints)