Two people look at a computer screen.
PAGE
MENU

Perioperative Neurocognitive Disorders

What are Perioperative Neurocognitive Disorders?

Anesthesia or surgery can affect an individual’s cognition, or, thinking and memory. Perioperative Neurocognitive Disorders (PNDs) are changes to a person’s behaviour or cognition that can occur either before or after surgery.

Types of Perioperative Neurocognitive Disorders

  • Postoperative Delirium: a state of confusion in the first 7 days after surgery.
    • Definition: A disturbance of consciousness, perception, memory, and orientation, which fluctuates throughout the day.
    • Symptoms:
      • Trouble with thinking and attention
      • Agitation or sleepiness
    • Diagnosis:
      • The Confusion Assessment Method is used to diagnose delirium.
  • Delayed Neurocognitive Recovery: a decline in cognition lasting up to 30 days after surgery.
    • Definition: A decline in cognitive function without delirium.
    • Symptoms:
      • Memory impairments
      • Reduced psychomotor skills
  • Postoperative Neurocognitive Disorder: a decline in memory and thinking lasting up to 12 months after surgery.
    • Definition: Any new cognitive impairment that exceeds the expected recovery period and/or lasts up to 12 months after surgery. There is typically no effect on consciousness, orientation, or attention.
    • Symptoms:
      • Memory impairments
      • Difficulty with combining tasks
      • Reduced psychomotor skills

      Mild vs Major:
      • In mild cases, daily function is maintained
      • In major cases, daily function is not maintained
  • Neurocognitive Disorder: is a decline in cognition occurring more than 12 months after surgery.
    • Definition: Any cognitive impairment that persists after one year. This includes both dementia (major) and cognitive impairment (mild).
    • Symptoms:
      • Long-term loss of brain function (mild cognitive impairment)
      • Severe, short-term loss of brain function (delirium, agitation and confusion)
    • Diagnosis: Periodic, regular cognitive assessment using validated neurocognitive tests that demonstrate decrease in function beyond that expected.


      Please contact your family doctor if you have concerns about your cognition.