Grand Rounds Review: Delirium

This morning, Dr. Sharon Inouye gave us an excellent overview of delirium, with a focus on acute delirium in the elderly. She is the director of the Aging Brain Institute and Professor of Medicine at the Harvard School of Medicine and Beth Isreal Deaconess Medical Center. As a leading expert in the field, Dr. Inouye developed the Confusion Assessment Method (CAM), an internationally recognized method for identifying delirium. Here is a synopsis of her talk, with salient points that directly apply to our clinical practice.

Risk Factors for Delirium

  • Underlying dementia
  • Older age
  • Co-morbid illness
  • Severity of medical illness
  • Infection
  • ‘High-risk’ medication use (see below!)
  • Diminished activities of daily living
  • Immobility
  • Sensory impairment (vision, hearing)
  • Urinary catheterization
  • Urea and electrolyte imbalance
  • Malnutrition

Potentially Inappropriate Medications for the Elderly

In 2012, the American College of Geriatrics released the Beers criteria for medications with potential harm (including risk for delirium) in the elderly – mant of the medications we most commonly use populate this list!

  • Anticholinergics
    • 1st generation antihistamines (diphenhydramine, chlorpheniramine, etc.)
    • Anti-parkinson agents (benztropine)
    • Anti-spasmodics (dicyclomine, hyoscyamine, etc.)
  • Anti-microbials (Nitrofurantoin – pulm toxicity)
  • CNS medications
    • Tricyclics (amitriptyline, imipramine, doxepin – very antichol)
    • Conventional and Atypical Anti-psychotics
    • Benzos (increased risk of cognitive impairment)
  • Sedative/Hypnotics (zolpidem, eszopiclone, etc.)
  • Anti-arrhythmics (disopyramide, etc.)
  • Antitussives (dextromethorphan, etc.)
  • Anti-vertigo meds (meclizine, etc.)
  • H2-blockers (famotidine, etc.)
  • Mydriatics (atropine, etc.)

The list goes on, for more information, click here.

Diagnosis/Identification of Delirium

The Confusion Assesment Method

CAM

(to use the CAM, click the image above to visit the HELP website)

Management

  • Non-pharmacologic measures are best! Guidelines do not recommend pharmacologic management as a first line, except for a few specific situations.
    • Re-orientation
    • Reduce medications
    • Reduce length of stay
    • Maintain day-night cycle
    • Familar surroundings and people
    • Remove catheters!
    • Maintain nutritional balance
  • Drug treatment may reduce agitation, but may prolong delirium duration and cognitive decline.
    • Pearl – reserve for patients with severe agitation which will:
      1. Cause interruption of essential medical therapy (i.e. intubation)
      2. Pose potential harm to the patient or staff
    • Recommended Approach: 
      • Haloperidol 0.25-0.50 mg PO or IM (avoid IV – short acting and can precipitate torsades de pointes)
      • Repeat dose q30 minutes until patient is manageable (maximum dose 3-5mg/24 hours)
      • Maintenance: 50% of loading dose divided over the next 24 hours
      • Taper dose of the next several days