Postoperative Neurocognitive Disorder
Background
-
Formerly known as Post-operative Cognitive Dysfunction (POCD)
-
Subtle cognitive impairment that differs from overt delirium
-
Consists of two syndromes:
-
Delayed neurocognitive recovery
-
patient is back to baseline by 30 days
-
-
Post-op neurocognitive disorder
-
cognitive decline which persists up to 12 months post-op
-
Mild = mild cognitive impairment (MCI) equivalent
-
Major = dementia equivalent
-
-
-
Pathophysiology
-
Thought to be secondary to inflammatory response of surgery
-
Considerations
-
Risk factors:
-
Age > 65, pre-operative cognitive impairment, critically ill, excessive EtOH use, polypharmacy, frailty, hx of stroke or TIA, other comorbid dz (DM, vascular dz), lower education level
-
Major ortho sx, cardiac sx, otherwise long sx
-
-
Useful to perform baseline cognitive screen (i.e. MMSSE or Mini-Cog) in suspected pts
-
Consider use of BIS or raw EEG monitor to avoid burst suppression
-
Employ cerebral oximetry to avoid drop in rSO2
-
No difference in incidence based on anesthetic technique (GA vs regional or inhalation vs IV)
Goals
-
Identify high-risk patients
-
If high-risk:
-
Avoid excessive anesthetic depth (i.e. burst suppression)
-
Avoid prolonged periods of hypotension
-
Avoid ↓ cerebral oximetry
-
Avoid benzos & gabapentinoids
-
Minimize opioids
-
-
Multi-modal analgesia for opioid-sparing effect
-
e.g. Acetominophen +/- NSAIDs +/- steroids +/- ketamine +/- dexmedetomidine infusion
-
-
Employ routine measures to avoid post-operative delirium (e.g. early mobilization, removing drains/restraints/lines etc.)
-
See post-operative Delirium
-
References
-
Olotu, Cynthia. Postoperative neurocognitive disorders. Current Opinion in Anaesthesiology 33(1):p 101-108, February 2020. DOI: 10.1097/ACO.0000000000000812