Delirium Flashcards
Definition of delirium
Neuropsychiatric syndrome (also called acute confusional state or acute brain failure) common agmonst medically ill, often misdiagnosed
DSM IV criteria for delirium
- Disturbance of consciousness with reduced ability to focus, sustain or shift attention
- A change in cognition or development of perceptual disturbances that is not better accounted for by a preexisting, existed or evolving dementia
- The disturbance develops over a short period of time and tends to fluctuate during the course of the day
- There is evidence from the history, PE or labs that the disturbance is caused by the physiological consequence of a medical condition
Clinical characteristics of delirium
- Develops acutely (hours to days)
- Characterized by fluctuating level of consciousness
- Reduced ability to maintain attention
- Agitation or hypersomnolence
- Extreme emotional lability
- Cognitive deficits can occur
Cognitive deficits in delirium
- Language difficulties: word finding difficulties, dysgraphia
- Speech disturbances: slurred, mumbling, incoherent or disorganized
- Memory dysfunction: marked short-term memory impairment, disorientation to person, place, time
- Perceptions: misinterpretations, illusions, delusions and/or visual (more common) or auditory hallucinations
- Constructional ability: can’t copy a pentagon
Types of delirium
Hyperactive or hyperalert
Hypoactive or hypoalert
Mixed
Hyperactive or hyperalert delirium
Hyperactive, combative and uncooperative
May appear to be responding to internal stimuli
Frequently these patients come to our attention because they are difficult to care for
Hypoactive or hypoalert delirium
Napping on and off throughout day
Unable to sustain attention when awakened, quickly falling back asleep
Misses meals, medications, appointment
Does not ask for care or attention
Easy to miss because caring for these patients is not problematic to staff
Most common types of delirium
Hypoactive and mixed account for ~80% of delirium
What percent of hospitalized elderly patients >65 y/o get delirium?
40%
Delirium etiology
Usually multifactorial
- systemic illness
- medications (any psychoactive med can cause delirium)
- presence of risk factors
What systemic illnesses can cause delirium?
Infections Electrolyte abnormalities Endocrine dysfunctions (hypo or hyper) Liver failure (hepatic encephalopathy) Renal failure (uremic encephalopathy) Pulmonary disease with hypoxemia Cardiovascular disease/events: CHF, arrhythmias, MI CNS pathology: tumors, strokes, seizures Deficiency states: thiamine, nicotinic or folic acid, B12
What drugs can cause delirium?
Anticholinergics (furosemide, digoxin, theophylline, cimetidine, prednisolone, TCA’s, captopril)
Analgesics (morphine, codeine)
Steroids
Antiparkinson (anticholinergic and dopaminergic)
Sedatives (benzodiazepines, barbiturates)
Anticonvulsants
Antihistamines
Antiarrhythmics (digitalis)
Antihypertensives
Antidepressants
Antimicrobials (penicillin, cephalosporins, quinolones)
Sympathomimetics
What are the predisposing risk factors for delirium?
- > 60 y/o
- Male sex
- Visual impairment
- Underlying brain pathology (e.g. stroke, tumor, vasculitis, trauma, dementia)
- Major medical illness
- Recent major surgery
- Depression
- Functional dependence
- Dehydration
- Substance abuse/dependence
- Hip fracture
- Metabolic abnormalities
- Polypharmacy
- Meds
- Severe acute illness
- UTI
- Hyponatremia
- Hypoxemia
- Shock
- Anemia
- Pain
- Orthopedic surgery
- Cardiac surgery
- ICU admission
- High number of hospital procedures
What do you have to rule out?
Wernicke’s Hypoxia Hypoglycemia Hypertensive encephalopathy Meningitis/encephalitis Poisoning Anticholinergic psychosis Subdural hematoma Septicemia Subacute bacterial endocarditis Hepatic or renal failure Thyrotoxicosis/myxedema Delirium tremens Complex partial seizures
Pathophysiology of delirium?
Hypotheses:
- Neurotransmitter abnormalities
- Inflammatory response with increased cytokines
- Changes in BBB permeability
- Widespread reduction in cerebral oxidative metabolism
- Increased activity of hypothalamic-pituitary-adrenal axis
What are the most sensitive items in identifying delirium with MMSE?
Serial 7’s, orientation, recall memory
- MMSE is not sensitive but can reveal waxing and waning course
Difference between delirium and psychiatric disorder?
Clouded consciousness or decreased level of alertness Disorientation Acuity of onset and course Age >40 without prior psych history Presence of risk factors
Dementia vs. Delirium?
Dementia: insidious onset, chronic memory and executive function disturbance, intact alertness and attention, impoverished speech and thinking
Delirium: cognitive changes develop acutely and fluctuate, speech can be confused or disorganized, alertness and attention wax and wane
Schizophrenia vs. Delirium?
Schizophrenia: Onset is rare after 50 AH more common than VH Memory is grossly intact Disorientation is rare Speech is not dysarthric No wide fluctuations over the course of a day
Mood disorders vs. Delirium?
Mood disorders:
Persistent rather than labile mood with more gradual onset
Mania:
Can be very agitated but cognitive performance is not usually as impaired
Flight of ideas usually have some thread of coherence unlike simple distractibility
Disorientation is unusual
Treatment for delirium?
Treat the UNDERLYING CAUSE
Environmental interventions
Minimize psychoactive medications
What do antipsychotics help with in delirium?
Decrease psychotic symptoms, confusion, and agitation
What is the first line treatment for delirium?
IV Haldol
Onset within 5-20 minutes
Can transition to BID or QHS oral dose and taper
Which atypical antipsychotics now have supporting data for use in delirium?
Risperdal 0.5-2 mg
Quetiapine 12.5-50 mg
Olanzapine 2.5-10 mg
