Transcript Delirium

Delirium: Aka Acute Mental
Status Changes
Historical Perspectives
• Descriptions exist prior to Hippocrates
• Phrenitis
– Acute transient mental disorder seen in
association with medical illness, with
psychomotor agitation, insomnia and
disturbances of mood/perception
• Lethargus
– Somnolence, inertia, reduced response to
stimuli
What Is Delirium?
• An acute disorder characterized by
disturbances in consciousness,
disorganized thinking, fluctuating course
with reduced ability to focus, sustain, or
shift attention
• Develops over a short time
• Disturbances in cognition (memory,
disorientation, perceptual/spatial
disturbance)
Eponyms for Delirium
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Acute confusional state
Toxic/metabolic encephalopathy
ICU psychosis
Organic brain syndrome
Hepatic encephalopathy
Beclouded dementia
“Sundowning”
Epidemiology of Delirium
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20% of hospitalized elders
50% of hip fracture patients
Annual costs ~ $8 billion dollars
Results in longer hospital stays,
morbidity, mortality, & nursing home
placement
• 32-67% of cases never detected
“Delirium, A Syndrome of Cerebral
Insufficiency”
“The physician who is greatly concerned
to protect the integrity of the heart, liver,
kidneys of his patient has not yet
learned to have the similar regard for
the functional integrity of his patient’s
brain”
Romano & Engel 1959 J Chron Dis
Delirium Is A Recognizable
Syndrome
• A syndrome with cognitive, psychiatric,
and neurological manifestations
• Understanding the key elements of the
syndrome is the most critical skill
• Remembering “laundry lists” of potential
causes is not useful
Delirium: Pearls
• Read the nursing and therapy staff
notes
– Often the consult is literally done before
ever having to see the patient
• Listen to families & don’t tell them their
loved one is “back to baseline” if they
state otherwise
• Educate families & other medical staff
Delirium Subtypes
• Hypervigilant
– Frequently associated with drug
intoxication/withdrawal (delirium tremens)
with increased arousal and autonomic
lability
• Hypovigilant or “quiet delirium”
– Somnolent, sluggish, and apathetic
• Mixed forms
Delirium: Cognitive Features
• A disorder of attention (ability to maintain a
coherent stream of thought, free of
interference from external or internal stimuli)
– Sustained attention
– Divided attention
– Ability to inhibit irrelevant stimuli
• Disorientation, poor memory, visuospatial
disturbances & language changes are in
large part due to disordered attention (unless
they pre-existed due to underlying dementia)
Delirium: Psychiatric Features
• Mood changes (depression, apathy,
irritability, anxiety, & mania)
• Psychosis is common!
– Suspiciousness, paranoid delusions
– Visual hallucinations
• Delirium is the most common cause of
new onset psychosis in the elderly
Delirium: Neurological
Features
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Asterixis
Action or postural tremor
Impaired postural control (balance)
Bowel and bladder incontinence
Motor tone abnormalities (gegenhalten
type rigidity)
Delirium Pearls
• The neuroanatomy of attention/arousal
is diffuse & vulnerable at many points
• Often the first to “fall apart” when elderly
patients get ill for whatever reason
• Precipitating cause is seldom “in the
brain itself”, such as a new stroke, brain
tumor, bleed, or CNS infection
Delirium Pearls
• CT scans, MRI scans, lumbar punctures
are seldom useful and often red
herrings
• If you got one, look at it (brain size,
vasculopathy, hippocampal atrophy,
ventricolomegaly)
• If you are completely unsure, then EEG
is helpful but rarely needed
Delirium & The Geriatric
Syndromes
• Delirious patients have decompensation
of other processes that rely on widely
distributed neural networks (maintaining
the upright posture and continence)
• Not surprisingly these recover together
• A person’s gait/balance may be just as
good an indicator of recovery from
delirium!
The Anatomy of Delirium
• Attention and arousal are dependent
upon widely distributed neural circuitry
and therefore vulnerable to a variety of
insults
• The neurotransmitters acetylcholine
(ACh) and dopamine seem particularly
important
Evidence for Cholinergic
Deficiency in Delirium
• Anticholinergic drugs cause delirium
• Cholinergic agonists reverse drug-induced
delirium
• Lewy body dementia mimics delirium
• Hypoxia, hyperglycemia, thiamine deficiency
cause decreased ACh release
• Alzheimer’s and other dementia at increased
risk
• Serum anticholinergic activity correlates with
delirium severity and incidence
Evidence for Dopaminergic
Excess in Delirium
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Dopamine agonists can cause delirium
Dopamine blockade treats delirium
Dopamine release increases in hypoxia
Dopamine is important in prefrontal
areas
• Dopamine density in prefrontal cortex
decreases with aging and correlates
with attentional measures
Clinical Manifestations of
Disordered Attention
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Distractibility
Poor persistence
Tangentiality and rambling incoherence
Intrusions of irrelevant information
– Results in inability to learn new
information, solve problems or engage in
goal-directed behavior
Clues to Detection!
• “Patient is pleasantly confused”
• “He kept speaking of going to the circus, &
had difficulty following directions”
• Patient stated “I want off this train. I am
choking”
• “Patient is very sleepy, and difficult to arouse”
• Patient had a “rough night, was up all night
and agitated”
Bedside Tests of Attention
• Digit span forwards and backwards
– Normal forwards is 7 +/- 2
– Backwards usually 2 less than forward
• Reciting overlearned tasks
– Alphabet
– Months forward, days of week
forward/backwards
Bedside Tests of Attention
• Counting 1-20 forwards, backwards
• Continuous performance task such as
the “A” test
– Raise and lower hand in response to
letter A
• Writing is extremely sensitive to delirium
– Draws on many complex skills and
falls apart early
Delirium Documentation
• Document the mental status examination
including description of cognitive/affective
features
– Record some test of attention (digit span, counting
span, months forward, alphabet etc.)
– Describe mood/behavior (irritability, hallucinations,
paranoia, apathy, mood lability, sadness, etc.)
• Document some neurologic exam (asterixis,
action tremor, poor balance/instability)
Delirium Work Up
• Studies
– CBC, CMP, urinalysis, pulse ox/ABG, EKG
– Physical examination
– Chest XRAY, other body imaging
– Sometimes drug screen, tsh, b12/folate,
thiamine, lumbar puncture, neuroimaging
– EEG can be useful in unclear cases
looking for diffuse slowing
Delirium: The Usual Suspects
• Medications! (perform a detailed review)
• Common geriatric infections (pneumonia,
urinary tract infections, abdominal infections,
cutaneous)
• Hip fracture
• Metabolic disturbances (glucose, sodium,
calcium, acid-base)
• Hypoxemia
• CHF, myocardial ischemia
The Importance of Medications
(Ng/ml Atropine Equivalents)
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Furosemide 0.22
Digoxin 0.25
Warfarin 0.12
Nifedipine 0.22
Isosorbide 0.15
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Ranitidine 0.22
Theophylline 0.44
Prednisone 0.55
Codeine 0.11
Cimetidine 0.86
General Approach to
Treatment
• Correct/remove all contributing factors
• Provide meticulous supportive care
(feeding, mobility, continence, pressure
wounds)
• Engage patient/family provide
reassurance
• Correct sensory deficits (glasses,
hearing aids, avoid complete darkness)
• Falls alarm, sitter, family member
General Approach to
Treatment
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Avoid too much or too little stimulation
Try to improve sleep/wake cycle
Avoid iatrogenesis (physical restraints)
Plan for discharge, follow-up and next
level of care
• Document your examination findings
Delirium Treatment:
Medications
• Antipsychotics are first line
• Benzodiazepines only for alcohol or
drug withdrawal states
• Occasionally cholinesterase inhibitors
may be useful and are likely to play an
important role as new research evolves
Delirium Treatment:
Medications
• Avoid benzodiazepines except for
alcohol/drug withdrawal
– Haloperidol recommended first line for most
• 0.5 mg q 3
– Avoid older sedating antipsychotics
(anticholinergic)
– Atypical antipsychotics
• Put on standing dose if requirement is
frequent and supplement with prn
• Goal is to treat cognition/psychiatric
dysfunction, not sedation!
Antipsychotics for Delirium
• Haldol generally favored
– Can be given IM, SQ, IV, PR, PO
– Low doses in elderly frail patients 0.5 mg
initially and then every 4 hrs
– Avoid in parkinsonian patients (need to
recognize EPS)
• Increasing use of “atypical
antipsychotics”
– Olanzapine, quetiapine, risperidone,
ziprasidone
Post Delirium Care
• Ensure not only medical but cognitive
follow up as well
• Document your exam for others
• Anticipate it will recur in the future and
try to optimize conditions so it will not
• Educate families about medications,
and the syndrome of delirium
Summary
• Delirium is a common, costly and morbid
condition
• Delirium is fundamentally a disorder of
attention
• Delirium is poorly recognized
• Many patients have unrecognized preexisting dementia
• Many patients will ultimately develop
dementia