MENTAL STATUS CHANGES

LEARNING OBJECTIVES :

KNOWLEDGE - Students should be able to define or describe:

  1. Define or describe mental status changes and the syndromes of dementia and delirium (acute confusional state) as well as psychiatric illnesses that may present as changes in mental status.
  2. Define or describe the major points of differentiation between dementia, delirium, and depression on history, physical examination, and mental status testing.
  3. Define or describe the differential diagnosis for dementia, the major causes of dementing illnesses, and the work-up for dementia.
  4. Define or describe the major causes for delirium (acute confusional states) and the diagnostic evaluation of the delirious patient.
  5. Define or describe that mental status changes are a common pathway of a variety of illnesses in older patients and that older people should not be assumed to be demented when they present with mental status changes.
  6. Recognize the risk factors for developing altered mental status, including:
    1. Dementia
    2. Advanced age
    3. Substance abuse
    4. Comorbid physical problems such as sleep deprivation, immobility, dehydration, pain, and sensory impairment
    5. ICU admission
  7. Discuss the pathophysiology, symptoms, and signs of the most common and most serious causes of altered mental status, including:
    1. Metabolic causes (e.g. hyper/hyponatremia, hyper/hypoglycemia, hypercalcemia, hyper/hypothyroidism, hypoxia/hypercapnea, B12 deficiency, hepatic encephalopathy, uremic encephalopathy, drug/alcohol intoxication/withdrawal, and Wernicke's encephalopathy).
    2. Structural lesions (e.g. primary or metastatic tumor, intracranial hemorrhage, subdural hematoma)
    3. Vascular (e.g. cerebrovascular accident, transient ischemic attack, cerebral vasculitis)
    4. Infectious etiologies (e.g. encephalitis, meningitis, urosepsis, endocarditis, pneumonia, cellulitis)
    5. Seizures/post-ictal state
    6. Hypertensive encephalopathy
    7. Low perfusion states (e.g. arrhythmias, MI, shock, acute blood loss, severe dehydration)
    8. Miscellaneous causes (e.g. fecal impaction, postoperative state, sleep deprivation, urinary retention)
  8. Develop a management plan for the most common causes of altered mental status including a diagnostic evaluation.
  9. Recognize the importance of thoroughly reviewing prescription medications, over-the-counter drugs, and supplements and inquiring about substance abuse.
  10. Identify nonpharmacologic measures to reduce agitation and aggression, including:
    1. Avoiding the use of physical restraints whenever possible
    2. Using reorientation techniques
    3. Assuring the patient has their devices to correct sensory deficits
    4. Promoting normal sleep and day/night awareness
    5. Preventing dehydration and electrolyte disturbances
    6. Avoiding medications which may worsen delirium whenever possible (e.g. anticholinergics, benzodiazepines, etc.).
  11. Identify the risks of using physical restraints.
  12. Define and describe the risk and benefits of using low-dose high potency antipsychotics for delirium associated agitation and aggression.
  13. Define or describe that mental status changes are a common event in the care of patients with HIV related illness.
  14. Identify indications, contraindications, and complications of lumbar puncture.

 

SKILLS - Students should be able to:

  1. Recognize altered mental status in a patient.
  2. Gather a history from a patient or other informants that helps to differentiate between dementia, delirium, or a psychiatric illness.
  3. Focus questions in the history that will elucidate the underlying etiology of the mental status change.
  4. Perform a thorough physical examination with emphasis on the neurological evaluation that assists in the diagnosis of mental status changes
  5. Do a screening mental status examination using the Folstein Mini-Mental State Exam and be able to interpret the results.
  6. Recognize that the differential diagnosis of a person with mental status changes includes delirium, a dementing illness, and a psychiatric illness such as depression, mania, or psychosis.   In considering the diagnosis of dementia, one must further differentiate between a dementia of the Alzheimer's type, vascular dementias (including multi-infarct dementia), other less common causes of dementia, and the "reversible" dementias (hypothyroidism, vitamin B12 deficiency, chronic subtotal hematoma, etc.).   For persons with acute confusional states/delirium, the differential centers on the underlying etiology and can be roughly divided into neurologic causes (trauma, stroke, seizure, infection), systemic causes, and psychiatric illness.   In individuals with HIV infection, mental status changes can have a long differential and include the AIDS dementia complex, another infectious process (e.g. Toxoplasmosis), a neoplastic process (e.g., CNS lymphoma), or any of the other reasons why an individual may have mental status changes.
  7. Order when appropriate and interpret the following laboratory examinations in the evaluation of a person with mental status changes:   CBC, electrolytes, glucose, BUN, creatinine, liver function tests, thyroid function tests, calcium, phosphorus, vitamin B12, VDRL, drug screen, arterial blood gases, lumbar puncture, CT scan, MRI scan, EEG.
  8. As necessary, perform a venipuncture for laboratory testing and, in selected cases, a lumbar puncture.

 

ATTITUDES AND PROFESSIONAL BEHAVIORS:

  1. Recognize the anxiety and concern of patients and their families with mental status changes and be able to provide empathic care with accurate information, appropriate support, and on-going care.
  2. Treat delirious and demented individuals with respect, concern and compassion.
  3. Be willing to assist and discuss care issues with the family of persons caring for individuals with dementing illnesses.

 

RECOMMENDED READINGS :

  1. Isselbacher KJ, Braunwald E, Wilson JD, et al (eds.):   Harrison's Principles of Internal Medicine
  2. Siu AL.   Screening for dementia and investigating its causes.   Annals of Internal Medicine.   1991;115:122-132. (A good reference regarding cost-effective approaches in the work-up of dementia)
  3. Malaz Boustani, Britt Peterson, Laura Hanson, Russell Harris, and Kathleen N. Lohr
    ” Screening for Dementia in Primary Care: A Summary of the Evidence for the U.S. Preventive Services Task Force”    Ann Intern Med , Jun 2003; 138: 927 - 937.
  4. Christopher M. Clark and Jason H.T. Karlawish   “ Alzheimer Disease: Current Concepts and Emerging Diagnostic and Therapeutic Strategies”    Ann Intern Med , Mar 2003; 138: 400 - 410.