Cause of delirium

• disturbance of consciousness
• change in cognition
  • memory deficits
  • disorientation
  • language disturbance 
• perceptual disturbance
  • hallucinations (perception without stimuli)
  • illusions
• fluctuation (alert in day, agitated at night)
• physiological consequeces

• changes in vital signs
• motor abnormalities (tremors, restlessness)
• other physical signs reflecting underlying cause
  • pupillary signs
  • asterixis
  • jaundice

• reduced awareness of the environment
• distractibility
• hallucinations
• delusions
• illusions

• advanced age
• serious illness
• dehydration
• polypharmacy
• pre-existing dementia
• electrolyte and metabolism problems
• post-op states
• sleep deprivation
• visual/hearing problems

• hyperactive delirium
• hypoactive delirium
• mixed

Delirium requires fluctuations in mood throughout the given day, and via medical history, you can see if there is any potential cause for delirium.

Reticular activating system: components

reticular formation

locus coeruleus

raphe nuclei

preoptic region

Where RAS projects into?

cortex

thalamus

cerebellum

• behavioral arousal
• regulation of muscular reflexes
• coordination of autonomic function
• modulation of painful sensations

• arousal of appropriate autonomic responses attendant to cortical arousal (ex: increase HR, BP, RR)
• increase tonus in skeletal muscle

• many different etiologies (we really dont know of any ONE)
  • involve RAS and/or both cerebral hemispheres
  • increase cytokines (inflam. process)
  • hypoxic states, decrease oxidative metabolism → defects in neurotransmitter systems
  • aging brain
  • disturbances in blood brain barrier permeability

can lead to delirium

• atropine
• anti-Parkinson agents
• dicyclomine

Differential diagnosis of delerium (what other things could it be?

• sleep disorders
• seizure disorders
• steriod induced mania
• severe mania secondary to bipolar disorder
• schizophrenia
• vitamine deficiency syndromes
  • B12
  • pellagra
  • thiamine

MUST TREAT THE CAUSE

•  if agitated, you can use antipsychotics

SPOCC

• support
• protect
• orient
• calm
• communicate

possible etiologies of delirium

WHHHIMP

• wernicke's
• hypoxia
• hypoglycemia
• hypertensive encephalitis
• intracerebral hemorrhage
• meningitis/encephalitis
• poisoning

• good history
• good neurological exam
• labs
• track symptoms over time
• bedside screening
  • clock drawing
  • DRS
  • MMSE

• behavioral/emotional disorders that are directly due to a medical disorder
• examples
  • hypothyroidism, stroke, pancreatic carcinoma cause depression
  • adrenal problems can cause mania
  • brain tumors such as acoustic neuromas can cause hallucinations