Delirium

Question 1

Clinical features

Answer 1

• fluctuations in severity
• clouding of consciousness
• reduced attention span
• distractibility
• global impairment of cogntiion with disorientation and impairment of recent memory
• abstract thinking is impaired
• disturbance in sleep/wake cycle
• nocturnal worsening of symptoms can occur along with psychomotor agitation and emotional lability
• speech may be rambling

Question 2

Causes

Answer 2

-no detected cause is found in 5-20% of cases

Question 3

Hyperactive delirium

Answer 3

-characterised by increased motor activity, agitation, hallucinations and inappropriate behaviour

Question 4

Hypoactive delirium

Answer 4

• characterised by reduced motor activity and lethargy

- poorer prognosis

Question 5

Prevalence of delirium

Answer 5

• among the elderly 10-15% of patients have delirium on admission
• 40% develop delirium during a hospital stay
• post-operatively- 5-75%
• ITU- 12-50%
• nursing homes -60%

Question 6

Onset

Answer 6

• usually sudden
• lasts less than 1 week
• can last longer for elderly patients
• patchy amnesia for the period of delirium
• may be a marker for subsequent development of dementia

Question 7

Pathway

Answer 7

• major pathway implicated is the dorsal tegmental pathway
• this projects from the mesenchephalic reticular formation to the tectum and thalamus
• reticular formation is the area for regulating attention and arousal
• ACh is the main neurotransmitter

Question 8

EEG in delirium

Answer 8

-generalised slowing of activity

Question 9

Delirium rating scale

Answer 9

• most widely used
• needs skilled clinician
• distinguishes delirium from dementia

Question 10

MMSE

Answer 10

• emphasizes neuropsychological functions linked to left cerebral hemispheric activity
• many core disturbances of delirium reflect non-dominant hemispheric functions

Question 11

Cognitive test for delirium

Answer 11

• newly developed instrument

- allows detailed investigation of a range of neuropsychological functions

Question 12

CAM

Answer 12

• confusion assessment method
• high sensitibity and specificity
• allows diagnosis of delirium
• reduced sensitivity when used by nursing staff rather than physicians

Question 13

Management of delirium

Answer 13

• identify and treat precipitating cause
• provide environmental and supportive measures
• avoid sedation unless severely agitated
• regular clinical review and follow up
• correct sensory impairments
• make environment safe
• low dose haloperidol is effective in management of both types of delirium
• can use olanzapine
• benzos cause delirium and increase falls