Delirium in Cancer

1. See Also
   1. Delirium
   2. Altered Level of Consciousness
   3. Mood Disorders in Cancer
2. Epidemiology
   1. Incidence in terminally ill patients: 25 to 85%
   2. Sedation required in 25% of patients
   3. Reversible in 50% of patients
3. Causes
   1. Hypoxia (e.g. Atelectasis)
   2. Dehydration (Blood Urea Nitrogen >18 mg/dl)
   3. Hepatic Encephalopathy
   4. Brain Metastases
   5. Uncontrolled pain
   6. Constipation
   7. Electrolyte disturbance
      1. Hypercalcemia
      2. Hyponatremia
   8. Infection or fever
      1. Urinary Tract Infection
      2. Pneumonia
   9. Medications
      1. Opioid Withdrawal
      2. Benzodiazepine Withdrawal
      3. Corticosteroids
      4. Metoclopramide
      5. Antihistamines (Hydroxyzine, Diphenhydramine, Zantac)
      6. NSAIDs
      7. Tricyclic Antidepressants
      8. Scopolamine
4. Risk Factors
   1. Impaired vision (Snellen Chart <20/70)
   2. Severe illness
   3. Cognitive Impairment (Mini-Mental State Exam <24)
   4. Major Depression (Mood Disorders in Cancer)
   5. Emotional stress
   6. Unfamiliar environment
   7. Immobilization
5. Management
   1. Consider potentially reversible causes above
   2. Consider gentle rehydration if dehydration suspected
   3. Reduce risk factors above
   4. Family member or sitter presence may calm patient
   5. Avoid precipitating events
      1. Avoid Physical Restraints
      2. Avoid Malnutrition
      3. Avoid adding more than three medications per day
      4. Avoid Bladder Catheterization
      5. Avoid frequent changes in environment or staff
   6. Consider medications for Delirium with Agitation refractory to other measures
      1. Haloperidol 0.5 to 5 mg PO, IV, SC, IM q2 to 12 hours
      2. Agents with less side effects but long response delay
         1. Risperidone
         2. Clozapine
         3. Olanzapine
   7. Consider short-acting sedation if refractory to above (risk of paradoxical Agitation)
      1. Lorazepam
      2. Midazolam
      3. Other measures reportedly used include Propofol (caution!!)
6. References
   1. Albert (2017) Am Fam Physician 95(6): 356-61 [PubMed]
   2. Casarett (2001) Ann Intern Med 135:32-40 [PubMed]
   3. Lawlor (2000) JAMA 284:2427-9 [PubMed]
   4. Ross (2001) Am Fam Physician 64(6):1019-26 [PubMed]