Delirium: Aka Acute Mental Status Changes

1. Delirium: Aka Acute Mental Status Changes

2. 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

3. 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)

4. Eponyms for Delirium • Acute confusional state • Toxic/metabolic encephalopathy • ICU psychosis • Organic brain syndrome • Hepatic encephalopathy • Beclouded dementia • “Sundowning”

5. Epidemiology of Delirium • 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

6. “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” “Delirium, A Syndrome of Cerebral Insufficiency” Romano & Engel 1959 J Chron Dis

7. 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

8. 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

9. 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

10. 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)

11. 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

12. Delirium: Neurological Features • Asterixis • Action or postural tremor • Impaired postural control (balance) • Bowel and bladder incontinence • Motor tone abnormalities (gegenhalten type rigidity)

13. 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

14. 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

15. 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!

16. 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

20. 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

21. Evidence for Dopaminergic Excess in Delirium • 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

22. Clinical Manifestations of Disordered Attention • 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

23. 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”

24. 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

25. 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

26. 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)

27. 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

29. 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

30. Furosemide 0.22 Digoxin 0.25 Warfarin 0.12 Nifedipine 0.22 Isosorbide 0.15 Ranitidine 0.22 Theophylline 0.44 Prednisone 0.55 Codeine 0.11 Cimetidine 0.86 The Importance of Medications(Ng/ml Atropine Equivalents)

31. 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

32. General Approach to Treatment • 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

33. 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

34. 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!

35. 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

36. 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

37. Summary • Delirium is a common, costly and morbid condition • Delirium is fundamentally a disorder of attention • Delirium is poorly recognized • Many patients have unrecognized pre-existing dementia • Many patients will ultimately develop dementia