DEFINITION & TERMINOLOGY
This term, defined by DSM-5, involves disturbances in attention, awareness, and cognition, developing acutely and fluctuating.
What is Delirium?
This neurotransmitter plays a "key role," with deficits linked to delirium caused by anticholinergic drugs, hypoxia, and hypoglycemia.
What is Acetylcholine? (or Cholinergic Deficiency)
This early, often subtle sign might be noted by family as the patient "isn't acting quite right" before more obvious delirium develops.
What is a Change in the Level of Awareness (or loss of mental clarity)?
The first step in recognizing delirium is noticing this acute change from the patient's usual state, often reported by family or caregivers.
What is a Change from Baseline Mental Status?
This commonly prescribed analgesic class, especially meperidine, is listed as a potential cause of delirium.
What are opioids?
This core DSM-5 feature of delirium is defined as a reduced ability to direct, focus, sustain, and shift attention.
What is a Disturbance in Attention?
EEG studies in the 1940s established delirium as a disturbance of global cortical function, characterized by slowing of this dominant posterior rhythm.
What is the Alpha Rhythm?
The article notes that hypersensitivity to these two sensory inputs can be a feature accompanying delirium.
What are Light and Sound?
This validated bedside instrument, taking about five minutes, assesses acute onset/fluctuation, inattention, disorganized thinking, and altered consciousness level.
What is the Confusion Assessment Method (CAM)?
Abrupt cessation of alcohol, barbiturates, benzodiazepines, or SSRIs can precipitate delirium.
What is Withdrawal?
According to DSM-5, the cognitive disturbance in delirium is not better explained by this type of pre-existing disorder.
What is a Preexisting, Evolving, or Established Neurocognitive Disorder (like Dementia)?
These proinflammatory agents, like interleukins and TNF-alpha, may play a role, especially in delirium associated with sepsis or hip fracture.
What are Cytokines?
A common perceptual disturbance in delirium where patients misinterpret real objects or shadows, perhaps seeing faces in patterns.
What are Illusions?
This specific bedside test of attention involves asking the patient to repeat increasingly long series of random numbers.
What is the Digit Span test?
This category includes dehydration, hyponatremia, hypernatremia, hypoglycemia, hypercalcemia, uremia, and liver failure.
What are Fluid and Electrolyte Disturbances / Metabolic Disorders?
Often used synonymously with delirium, this term indicates a problem with coherent thinking where patients can't think with normal speed, clarity, or coherence.
What is Confusion?
Factors like hospitalization, surgery, underlying dementia, advanced age, or sensory impairment make the brain more susceptible to delirium; these are known as this type of factor.
What are Predisposing Factors?
These false sensory perceptions, often visual in delirium (like seeing people or shapes not actually present), occur without external stimuli.
What are Hallucinations?
A comprehensive review of these is crucial, as toxicity accounts for about 30% of delirium cases. The article suggests asking family to bring in everything from the medicine cabinet.
What are Medications (including prescription, OTC, supplements, others meds)?
This common pre-existing brain disease is noted as present in nearly half of older patients with delirium and significantly increases vulnerability.
What is Dementia?
The DSM-5 criteria specify that delirium involves disturbances in domains like memory, orientation, language, visuospatial ability, or this one dealing with interpreting sensory input.
What is Perception?
The article mentions the possibility that these substances, produced by the body itself, might play a role in delirium in some patients even without drug exposure.
What are Endogenous Anticholinergic Substances?
This phase, especially in older patients, may precede overt delirium and includes symptoms like fatigue, sleep disturbance, anxiety, restlessness, and irritability.
What is Prodromal Phase?
This diagnostic test is useful for excluding nonconvulsive status epilepticus (NCSE), especially when the cause of altered mental status is obscure.
What is an Electroencephalogram (EEG)?
The article notes that these agents, used for Parkinson's disease (like Levodopa), can precipitate delirium.
What are Dopamine Agonists?