CASE 4 - Delirium Flashcards
What is delirium?
A syndrome of acute confusion characterised by fluctuations in awareness, attention, and cognition that fulfils the DSM-5 criteria.
Explain the difference between DEMENTIA and DELIRIUM
DEMENTIA: slow mental decline over months-years. Early on, patients are alert, behave normally, and have NO hallucinations.
DELIRIUM: usually SUDDEN in onset, symptoms fluctuate during the day, and resolve when the CAUSE is addressed (can take hours - months to resolve).
Describe HYPERACTIVE delirium
HYPERACTIVE DELIRIUM:
- Increased agitation
- Incoherent speech, disorganised thoughts, disorientation
- Hallucinations
- Delusions (things that haven’t happened, or happened years ago)
Describe HYPOACTIVE delirium
HYPOACTIVE DELIRIUM:
- Withdrawn, sullen, sulky
- Less reactive
- Afraid of having hallucinations
What is MIXED delirium?
Switching between hypoactive + hyperactive delirium,
Delirium is typically secondary to…
I WATCH DEATH
I - infection
W - withdrawal A - acute metabolic disorder T - trauma C - CNS pathology H - hypoxia
D - deficiencies E - endocrine A - acute vascular disorder T - toxins/drugs H - heavy metals S - sleep disturbances
+ongoing symptoms (e.g. urinary retention, constipation, pain, dehydration)
Which patients are most susceptible to delirium?
Paediatric
Elderly (>65 years)
Hospitalised
Name the 3 cardinal signs of delirium (3 C’s)
CONSCIOUS - state is altered (e.g. stupor, drowsiness, hyper-vigilance, agitation)
COGNITIVE - impairment (inattention, disorientation, memory, inability to focus, emotional lability, hallucinations)
COURSE - is fluctuating, with an acute onset. Lasts hours-days. It is reversible once the underlying cause is treated.
https://www.youtube.com/watch?v=dhlkyIiD_RA
What is sundowning?
A state of confusion that worsens in the late afternoon and at night.
Present in illnesses such as dementia, delirium, and Parkinson’s
What is delirium tremens?
A life-threatening complication of alcohol withdrawal, typically onset within 72-96 hours after cessation of reduction.
Features include delirium, neurological impairment, and worsening autonomic function (tachycardia, HTN, nausea, sweating, anxiety)
Compare the following features of delirium and dementia:
ONSET
ATTENTION
FLUCTUATION
ONSET: sudden in delirium. Gradual in dementia.
ATTENTION: impaired in delirium (can’t focus). Early stages of dementia generally have little impact on attention; patient is still alert.
FLUCTUATION: changes several times during the day in delirium. Steady and gradually progressive in dementia.
Name 3 medications that can contribute to delirium
- Opioids
- Benzodiazepines
- Anticholinergics
- NSAIDs
- Corticosteroids
Describe the DSM-5 criteria that must be fulfilled for a diagnosis of delirium
- Attention and awareness are impaired
- 1 or more cognitive deficits (e.g. memory, disorientation, language)
- Acute onset over hours or days with waxing and waning severity
- Fulfils the following criteria: ABSENCE of pre-existing dementia, coma, or severely reduced responsiveness + EVIDENCE of organic underlying cause
(AAACC)
Why is it important to obtain collateral history (e.g. from family members, a spouse, a carer) in someone with suspected delirium?
Helps establish baseline function and determine whether the presentation of delirium is acute or fits into a more chronic pattern of disease
How is delirium diagnosed?
Clinical diagnosis
What is the most common cause of delirium?
Metabolic diseases / metabolic encephalopathy
e.g. diabetes mellitus, liver of kidney failure, hypo/hyperthyroidism, vitamin deficiencies, electrolyte abnormalities
What is the most common cause of delirium in ELDERLY patients?
UTI
Why is delirium a medical emergency?
It can be the first sign of a severe underlying illness
Name 2 tests that can be used identify delirium
4AT test
CAM (confusion assessment method)
Describe the 4AT test
4 domains: alertness, AMT4, attention, acute change or fluctuating course
- Alertness = drowsiness vs. hyperactivity
- AMT4 = age, DOB, place, year
- ATTENTION = ‘please state the months of the year backwards, starting from December’
- ACUTE CHANGE OR FLUCTUATING COURSE = evidence of significant change or fluctuation in: alertness, cognition, other mental function (eg. paranoia, hallucinations) arising over the last 2 weeks and still evident in last 24hrs
SCORED OUT OF 12. A SCORE OF 4 OR ABOVE SUGGESTS DELIRIUM +/- COGNITIVE IMPAIRMENT
https://static1.squarespace.com/static/543cac47e4b0388ca43554df/t/5f0592e7917a0733e509ea0b/1594200808505/4AT+v1_2+Oct+2014.pdf
What is the CAM assessment?
CAM = confusion assessment method
There are 4 features (acute onset w/fluctuating course, inattention, altered consciousness, thinking is disorganised).
Diagnosis of delirium requires the presence of features 1 and 2, PLUS either 3 or 4
https://www.amboss.com/us/knowledge/Delirium/
Name 4 routine laboratory studies that are recommended in someone with a new presumptive delirium diagnosis, and explain what you might expect each one to show
- CBE: looking for low Hb, leukocytosis
- BMP: glucose, renal function, electrolyte abnormalities
- URINALYSIS: UTI is a common cause of delirium in the elderly. Would expect pyuria, bacteriuria. Urinary casts in renal failure.
- LFTs: may show liver toxicity, alcoholism, etc.
DEPENDING ON CLINICAL SUSPICION, CAN ALSO ORDER: CXR, brain imaging, drug and alcohol tests
Name 5 interventions that can help mitigate risk factors for delirium
- Provide time-orienting objects (e.g. calendar, clock, windows with outside views)
- Cognitive stimulation (visits from family and friends)
- Facilitation of physiologic sleep (minimise noise and medical/nursing procedures at night, give earplugs)
- Avoiding or monitoring problematic medications
- Early mobilisation & refrain from using physical restraints
- Managing pain
- Managing medical conditions that cause or exacerbate delirium
Name 3 drug classes with anticholinergic effects (that will therefore increase the risk of delirium)
- Antihistamines
- Antimuscarinics
- Antipsychotics
Name 3 common causes of viral encephalitis
- Herpes simplex virus (type 1 and 2)
- Enteroviruses
- VZV
How can meningitis be differed from encephalitis upon history/physical exam?
Encephalitis is more likely to present with:
- Altered behaviour/mental status
- Personality changes
- Motor and sensory deficits
- Alternations in speech or movement.
Would symptoms of meningism (photophobia, neck stiffness) be present in pure encephalitis?
NO.
But signs of meningism would be present in MENINGOENCEPHALITIS.
An MRI showing temporal lobe involvement is seen in which type of viral encephalitis?
Most suggestive of HSV (herpes simplex virus) encephalitis
But other viruses (VZV, EBV) can also produce this clinical picture
Describe the CSF results seen in viral CNS infection
- Mildly raised WCC (no more than 250/mm3) with lymphocyte predominance (can be neutrophil predominant in early stages)
- Elevated proteins (usually <150/mm3)
- Normal glucose (>50% of blood value)
- Absence of red cells
Name 4 ACUTE complications of viral encephalitis
- Seizures
- SIADH
- Raised ICP
- Coma
Name 3 LONG-TERM complications of viral encephalitis
- Paresis
- Cognitive deficits
- Psychopathological symptoms
The diagnosis of viral encephalitis is best confirmed with which investigation?
PCR
CSF PCR for HSV-1 and HSV-2 is the gold standard
How soon after symptoms onset does PCR return a positive result (in the case of herpes simplex encephalitis)
Usually positive within 24 hours of symptoms onset and through the first week of treatment
What is the immediate treatment for viral encephalitis?
Immediate treatment with IV aciclovir without waiting for diagnostic confirmation
How long should aciclovir be continued for?
14 - 21 days
Name 2 common adverse effects of aciclovir
NV Diarrhoea Headache Hallucinations (at high doses) Encephalopathy
Monitor for: nephrotoxicity
What does an MRI measure?
Densities
Which age groups does herpes simplex encephalitis (HSE) commonly affect?
HSE has a bimodal distribution, mostly affecting:
- Patients younger than 20 years
- Patients older than 50 years
What is the mortality rate of HSE if left untreated?
70% mortality rate
Which imaging modality is most sensitive and specific for HSE?
MRI head
Describe the characteristic findings of HSE on MRI
Unilateral or bilateral temporal lobe oedema and/or haemorrhage
What is PSYCHOSIS?
A distorted perception of reality, typically characterised by delusions, hallucination, and/or disorganised behaviour.
Compare the following aspects of DELIRIUM and PSYCHOSIS:
- Onset
- Orientation to person, place, and time
- Hallucinations
- ONSET: sudden, acute onset in delirium
- ORIENTATION: delirious patients are NOT oriented to person/place/time. Psychotic patients are oriented.
- HALLUCINATIONS: can be present in both
What is the mechanism of action of levetiracetam?
How is it cleared?
Does it have any drug interactions?
Novel MOA: nobody really knows
Renally-cleared
No drug interactions (differs from other common anti-epileptics, i.e. valproate and carbamazepine)
Name 4 adverse effects of levetiracetam.
Which patients groups are most at risk of these adverse effects?
Behavioural/mood changes: depression, anxiety, emotional lability, hostility, aggression, nervousness
Those with learning disabilities or a history of psychiatric illness are most at risk.
Why is it important to counsel the patient and their family members about the adverse effects of levetiracetam?
The adverse effects of levetiracetam are related to behavioural changes (anxiety, depression, emotional lability, hostility, aggression).
It is important to inform them of this, in addition to asking about it at follow-up appointments because they may not volunteer this information (especially if they don’t connect it to the medication).
Important if they’ve got a learning disability or psychiatric history.
Outline the approach to delirium treatment
- Treat the underlying cause (e.g. infection, metabolic disturbance)
- Supportive measures (ear plugs, sleep cycle, re-orientation, family visits)
- Halopiderol (only if necessary - drugs are not necessary in most patients with delirium): an anti-psychotic
State the indications, MOA, and adverse effects of haloperidol
MOA: blockade of dopaminergic transmission in various parts of the brain
INDICATIONS:
- Acute and chronic psychoses
- Acute mania
- Tourette syndrome and other choreas
- Adjunct in treatment of hallucinations due to alcohol withdrawal (if diazepam inadequate)
- Intractable nausea and vomiting associated with cancer chemotherapy or radiotherapy
ADVERSE EFFECTS:
- Sedation
- Anxiety
- Agitation
- Neuroepileptic malignant syndrome (NMS: SERIOUS)
Which class of drugs should be avoided at all costs in someone with delirium?
What is the exception?
BENZODIAZAPENES should be avoided at all costs, UNLESS the patient is suffering from alcohol withdrawal
